Glaucoma is a group of eye conditions that damage the optic nerve.

Glaucoma is a group of eye conditions that damage the optic nerve. The optic nerve sends visual information from your eye to your brain and is vital for good vision. Damage to the optic nerve is often related to high pressure in your eye. But glaucoma can happen even with normal eye pressure.

Glaucoma can occur at any age but is more common in older adults. It is one of the leading causes of blindness for people over the age of 60.

Many forms of glaucoma have no warning signs. The effect is so gradual that you may not notice a change in vision until the condition is in its later stages.

It’s important to have regular eye exams that include measurements of your eye pressure. If glaucoma is recognized early, vision loss can be slowed or prevented. If you have glaucoma, you’ll need treatment or monitoring for the rest of your life.


The symptoms of glaucoma depend on the type and stage of your condition.

Open-angle glaucoma

  • No symptoms in early stages
  • Gradually, patchy blind spots in your side vision. Side vision also is known as peripheral vision
  • In later stages, difficulty seeing things in your central vision

Acute angle-closure glaucoma

  • Severe headache
  • Severe eye pain
  • Nausea or vomiting
  • Blurred vision
  • Halos or colored rings around lights
  • Eye redness

Normal-tension glaucoma

  • No symptoms in early stages
  • Gradually, blurred vision
  • In later stages, loss of side vision

Glaucoma in children

  • A dull or cloudy eye (infants)
  • Increased blinking (infants)
  • Tears without crying (infants)
  • Blurred vision
  • Nearsightedness that gets worse
  • Headache

Pigmentary glaucoma

  • Halos around lights
  • Blurred vision with exercise
  • Gradual loss of side vision

When to see a doctor

If you experience symptoms that come on suddenly, you may have acute angle-closure glaucoma. Symptoms include severe headache and severe eye pain. You need treatment as soon as possible. Go to an emergency room or call an eye doctor’s (ophthalmologist’s) office immediately.


Glaucoma develops when the optic nerve becomes damaged. As this nerve gradually deteriorates, blind spots develop in your vision. For reasons that doctors don’t fully understand, this nerve damage is usually related to increased pressure in the eye.

Elevated eye pressure happens as the result of a buildup of fluid that flows throughout the inside of the eye. This fluid also is known as the aqueous humor. It usually drains through a tissue located at the angle where the iris and cornea meet. This tissue also is called the trabecular meshwork. The cornea is important to vision because it lets light into the eye. When the eye makes too much fluid or the drainage system doesn’t work properly, eye pressure may increase.

Open-angle glaucoma

This is the most common form of glaucoma. The drainage angle formed by the iris and cornea remains open. But other parts of the drainage system don’t drain properly. This may lead to a slow, gradual increase in eye pressure.

Angle-closure glaucoma

This form of glaucoma occurs when the iris bulges. The bulging iris partially or completely blocks the drainage angle. As a result, fluid can’t circulate through the eye and pressure increases. Angle-closure glaucoma may occur suddenly or gradually.

Normal-tension glaucoma

No one knows the exact reason why the optic nerve becomes damaged when eye pressure is normal. The optic nerve may be sensitive or experience less blood flow. This limited blood flow may be caused by the buildup of fatty deposits in the arteries or other conditions that damage circulation. The buildup of fatty deposits in the arteries also is known as atherosclerosis.

Glaucoma in children

A child may be born with glaucoma or develop it in the first few years of life. Blocked drainage, injury or an underlying medical condition may cause optic nerve damage.

Pigmentary glaucoma

In pigmentary glaucoma, small pigment granules flake off from the iris and block or slow fluid drainage from the eye. Activities such as jogging sometimes stir up the pigment granules. That leads to a deposit of pigment granules on tissue located at the angle where the iris and cornea meet. The granule deposits cause an increase in pressure.

Glaucoma tends to run in families. In some people, scientists have identified genes related to high eye pressure and optic nerve damage.

Risk factors

Glaucoma can damage vision before you notice any symptoms. So be aware of these risk factors:

  • High internal eye pressure, also known as intraocular pressure
  • Age over 55
  • Black, Asian or Hispanic heritage
  • Family history of glaucoma
  • Certain medical conditions, such as diabetes, migraines, high blood pressure and sickle cell anemia
  • Corneas that are thin in the center
  • Extreme nearsightedness or farsightedness
  • Eye injury or certain types of eye surgery
  • Taking corticosteroid medicines, especially eye drops, for a long time

Some people have narrow drainage angles, putting them at increased risk of angle-closure glaucoma.


These steps may help detect and manage glaucoma in its early stages. That may help to prevent vision loss or slow its progress.

  • Get regular eye examinations. Regular comprehensive eye exams can help detect glaucoma in its early stages, before significant damage occurs. As a general rule, the American Academy of Ophthalmology recommends a comprehensive eye exam every 5 to 10 years if you’re under 40 years old; every 2 to 4 years if you’re 40 to 54 years old; every 1 to 3 years if you’re 55 to 64 years old; and every 1 to 2 years if you’re older than 65.If you’re at risk of glaucoma, you’ll need more frequent screening. Ask your health care provider to recommend the right screening schedule for you.
  • Know your family’s eye health history. Glaucoma tends to run in families. If you’re at increased risk, you may need more frequent screening.
  • Wear eye protection. Serious eye injuries can lead to glaucoma. Wear eye protection when using power tools or playing sports.
  • Take prescribed eye drops regularly. Glaucoma eye drops can significantly reduce the risk that high eye pressure will progress to glaucoma. Use eye drops as prescribed by your health care provider even if you have no symptoms.

Lung cancer is a type of cancer that begins in the lungs.


Lung cancer is a type of cancer that begins in the lungs. Your lungs are two spongy organs in your chest that take in oxygen when you inhale and release carbon dioxide when you exhale.

Lung cancer is the leading cause of cancer deaths worldwide.

People who smoke have the greatest risk of lung cancer, though lung cancer can also occur in people who have never smoked. The risk of lung cancer increases with the length of time and number of cigarettes you’ve smoked. If you quit smoking, even after smoking for many years, you can significantly reduce your chances of developing lung cancer.


Lung cancer typically doesn’t cause signs and symptoms in its earliest stages. Signs and symptoms of lung cancer typically occur when the disease is advanced.

Signs and symptoms of lung cancer may include:

  • A new cough that doesn’t go away
  • Coughing up blood, even a small amount
  • Shortness of breath
  • Chest pain
  • Hoarseness
  • Losing weight without trying
  • Bone pain
  • Headache

When to see a doctor

Make an appointment with your doctor if you have any persistent signs or symptoms that worry you.

If you smoke and have been unable to quit, make an appointment with your doctor. Your doctor can recommend strategies for quitting smoking, such as counseling, medications and nicotine replacement products.


Smoking causes the majority of lung cancers — both in smokers and in people exposed to secondhand smoke. But lung cancer also occurs in people who never smoked and in those who never had prolonged exposure to secondhand smoke. In these cases, there may be no clear cause of lung cancer.

How smoking causes lung cancer

Doctors believe smoking causes lung cancer by damaging the cells that line the lungs. When you inhale cigarette smoke, which is full of cancer-causing substances (carcinogens), changes in the lung tissue begin almost immediately.

At first your body may be able to repair this damage. But with each repeated exposure, normal cells that line your lungs are increasingly damaged. Over time, the damage causes cells to act abnormally and eventually cancer may develop.

Types of lung cancer

Doctors divide lung cancer into two major types based on the appearance of lung cancer cells under the microscope. Your doctor makes treatment decisions based on which major type of lung cancer you have.

The two general types of lung cancer include:

  • Small cell lung cancer. Small cell lung cancer occurs almost exclusively in heavy smokers and is less common than non-small cell lung cancer.
  • Non-small cell lung cancer. Non-small cell lung cancer is an umbrella term for several types of lung cancers. Non-small cell lung cancers include squamous cell carcinoma, adenocarcinoma and large cell carcinoma.

Risk factors

A number of factors may increase your risk of lung cancer. Some risk factors can be controlled, for instance, by quitting smoking. And other factors can’t be controlled, such as your family history.

Risk factors for lung cancer include:

  • Smoking. Your risk of lung cancer increases with the number of cigarettes you smoke each day and the number of years you have smoked. Quitting at any age can significantly lower your risk of developing lung cancer.
  • Exposure to secondhand smoke. Even if you don’t smoke, your risk of lung cancer increases if you’re exposed to secondhand smoke.
  • Previous radiation therapy. If you’ve undergone radiation therapy to the chest for another type of cancer, you may have an increased risk of developing lung cancer.
  • Exposure to radon gas. Radon is produced by the natural breakdown of uranium in soil, rock and water that eventually becomes part of the air you breathe. Unsafe levels of radon can accumulate in any building, including homes.
  • Exposure to asbestos and other carcinogens. Workplace exposure to asbestos and other substances known to cause cancer — such as arsenic, chromium and nickel — can increase your risk of developing lung cancer, especially if you’re a smoker.
  • Family history of lung cancer. People with a parent, sibling or child with lung cancer have an increased risk of the disease.


Lung cancer can cause complications, such as:

  • Shortness of breath. People with lung cancer can experience shortness of breath if cancer grows to block the major airways. Lung cancer can also cause fluid to accumulate around the lungs, making it harder for the affected lung to expand fully when you inhale.
  • Coughing up blood. Lung cancer can cause bleeding in the airway, which can cause you to cough up blood (hemoptysis). Sometimes bleeding can become severe. Treatments are available to control bleeding.
  • Pain. Advanced lung cancer that spreads to the lining of a lung or to another area of the body, such as a bone, can cause pain. Tell your doctor if you experience pain, as many treatments are available to control pain.
  • Fluid in the chest (pleural effusion). Lung cancer can cause fluid to accumulate in the space that surrounds the affected lung in the chest cavity (pleural space).Fluid accumulating in the chest can cause shortness of breath. Treatments are available to drain the fluid from your chest and reduce the risk that pleural effusion will occur again.
  • Cancer that spreads to other parts of the body (metastasis). Lung cancer often spreads (metastasizes) to other parts of the body, such as the brain and the bones.Cancer that spreads can cause pain, nausea, headaches, or other signs and symptoms depending on what organ is affected. Once lung cancer has spread beyond the lungs, it’s generally not curable. Treatments are available to decrease signs and symptoms and to help you live longer.


There’s no sure way to prevent lung cancer, but you can reduce your risk if you:

  • Don’t smoke. If you’ve never smoked, don’t start. Talk to your children about not smoking so that they can understand how to avoid this major risk factor for lung cancer. Begin conversations about the dangers of smoking with your children early so that they know how to react to peer pressure.
  • Stop smoking. Stop smoking now. Quitting reduces your risk of lung cancer, even if you’ve smoked for years. Talk to your doctor about strategies and stop-smoking aids that can help you quit. Options include nicotine replacement products, medications and support groups.
  • Avoid secondhand smoke. If you live or work with a smoker, urge him or her to quit. At the very least, ask him or her to smoke outside. Avoid areas where people smoke, such as bars and restaurants, and seek out smoke-free options.
  • Test your home for radon. Have the radon levels in your home checked, especially if you live in an area where radon is known to be a problem. High radon levels can be remedied to make your home safer. For information on radon testing, contact your local department of public health or a local chapter of the American Lung Association.
  • Avoid carcinogens at work. Take precautions to protect yourself from exposure to toxic chemicals at work. Follow your employer’s precautions. For instance, if you’re given a face mask for protection, always wear it. Ask your doctor what more you can do to protect yourself at work. Your risk of lung damage from workplace carcinogens increases if you smoke.
  • Eat a diet full of fruits and vegetables. Choose a healthy diet with a variety of fruits and vegetables. Food sources of vitamins and nutrients are best. Avoid taking large doses of vitamins in pill form, as they may be harmful. For instance, researchers hoping to reduce the risk of lung cancer in heavy smokers gave them beta carotene supplements. Results showed the supplements actually increased the risk of cancer in smokers.
  • Exercise most days of the week. If you don’t exercise regularly, start out slowly. Try to exercise most days of the week.

Heart disease describes a range of conditions that affect the heart


Heart disease describes a range of conditions that affect the heart. Heart diseases include:

  • Blood vessel disease, such as coronary artery disease
  • Irregular heartbeats (arrhythmias)
  • Heart problems you’re born with (congenital heart defects)
  • Disease of the heart muscle
  • Heart valve disease

Many forms of heart disease can be prevented or treated with healthy lifestyle choices.


Heart disease symptoms depend on the type of heart disease.

Symptoms of heart disease in the blood vessels

Coronary artery disease is a common heart condition that affects the major blood vessels that supply the heart muscle. Cholesterol deposits (plaques) in the heart arteries are usually the cause of coronary artery disease. The buildup of these plaques is called atherosclerosis (ath-ur-o-skluh-ROE-sis). Atherosclerosis reduces blood flow to the heart and other parts of the body. It can lead to a heart attack, chest pain (angina) or stroke.

Coronary artery disease symptoms may be different for men and women. For instance, men are more likely to have chest pain. Women are more likely to have other symptoms along with chest discomfort, such as shortness of breath, nausea and extreme fatigue.

Symptoms of coronary artery disease can include:

  • Chest pain, chest tightness, chest pressure and chest discomfort (angina)
  • Shortness of breath
  • Pain in the neck, jaw, throat, upper belly area or back
  • Pain, numbness, weakness or coldness in the legs or arms if the blood vessels in those body areas are narrowed

You might not be diagnosed with coronary artery disease until you have a heart attack, angina, stroke or heart failure. It’s important to watch for heart symptoms and discuss concerns with your health care provider. Heart (cardiovascular) disease can sometimes be found early with regular health checkups.

What is coronary artery disease? A Mayo Clinic cardiologist explains.

Stephen Kopecky, M.D., talks about the risk factors, symptoms and treatment of coronary artery disease (CAD). Learn how lifestyle changes can lower your risk.

Heart disease symptoms caused by irregular heartbeats (heart arrhythmias)

The heart may beat too quickly, too slowly or irregularly. Heart arrhythmia symptoms can include:

  • Chest pain or discomfort
  • Dizziness
  • Fainting (syncope) or near fainting
  • Fluttering in the chest
  • Lightheadedness
  • Racing heartbeat (tachycardia)
  • Shortness of breath
  • Slow heartbeat (bradycardia)

Heart disease symptoms caused by congenital heart defects

Serious congenital heart defects usually are noticed soon after birth. Congenital heart defect symptoms in children could include:

  • Pale gray or blue skin or lips (cyanosis)
  • Swelling in the legs, belly area or areas around the eyes
  • In an infant, shortness of breath during feedings, leading to poor weight gain

Less-serious congenital heart defects are often not diagnosed until later in childhood or during adulthood. Symptoms of congenital heart defects that usually aren’t immediately life-threatening include:

  • Easily getting short of breath during exercise or activity
  • Easily tiring during exercise or activity
  • Swelling of the hands, ankles or feet

Heart disease symptoms caused by diseased heart muscle (cardiomyopathy)

Early stages of cardiomyopathy may not cause noticeable symptoms. As the condition worsens, symptoms may include:

  • Dizziness, lightheadedness and fainting
  • Fatigue
  • Feeling short of breath during activity or at rest
  • Feeling short of breath at night when trying to sleep or waking up short of breath
  • Irregular heartbeats that feel rapid, pounding or fluttering
  • Swollen legs, ankles or feet

Heart disease symptoms caused by heart valve problems (valvular heart disease)

The heart has four valves — the aortic, mitral, pulmonary and tricuspid valves. They open and close to move blood through the heart. Many things can damage the heart valves. A heart valve may become narrowed (stenosis), leaky (regurgitation or insufficiency) or close improperly (prolapse).

Valvular heart disease is also called heart valve disease. Depending on which valve isn’t working properly, heart valve disease symptoms generally include:

  • Chest pain
  • Fainting (syncope)
  • Fatigue
  • Irregular heartbeat
  • Shortness of breath
  • Swollen feet or ankles

Endocarditis is an infection that affects the heart valves and inner lining of the heart chambers and heart valves (endocardium). Endocarditis symptoms can include:

  • Dry or persistent cough
  • Fever
  • Heartbeat changes
  • Shortness of breath
  • Skin rashes or unusual spots
  • Swelling of the legs or belly area
  • Weakness or fatigue

When to see a doctor

Seek emergency medical care if you have these heart disease symptoms:

  • Chest pain
  • Shortness of breath
  • Fainting

Always call 911 or emergency medical help if you think you might be having a heart attack.

Heart disease is easier to treat when detected early. Talk to your health care provider if you have any concerns about your heart health. Together, you and your provider can discuss ways to reduce your heart disease risk. This is especially important if you have a family history of heart disease.

If you think you may symptoms of heart disease, make an appointment to see your provider.


Heart disease causes depend on the specific type of heart disease. There are many different types of heart disease.

How the heart works

To understand the causes of heart disease, it may help to understand how the heart works.

  • The heart is divided into chambers — two upper chambers (atria) and two lower chambers (ventricles).
  • The right side of the heart moves blood to the lungs through blood vessels (pulmonary arteries).
  • In the lungs, blood picks up oxygen and then returns to the left side of the heart through the pulmonary veins.
  • The left side of the heart then pumps the blood through the aorta and out to the rest of the body.

Heart valves

Four heart valves — the aortic, mitral, pulmonary and tricuspid — keep the blood moving the right way. The valves open only one way and only when they need to. Valves must open all the way and close tightly so there’s no leakage.


A beating heart squeezes (contracts) and relaxes in a continuous cycle.

  • During contraction (systole), the lower heart chambers (ventricles) squeeze tight. This action forces blood to the lungs and the rest of the body.
  • During relaxation (diastole), the ventricles fill with blood from the upper heart chambers (atria).

Electrical system

The heart’s electrical system keeps it beating. The heartbeat controls the continuous exchange of oxygen-rich blood with oxygen-poor blood. This exchange keeps you alive.

  • Electrical signals start in the upper right chamber (right atrium).
  • The signals travel through specialized pathways to the lower heart chambers (ventricles). This tells the heart to pump.

Causes of coronary artery disease

A buildup of fatty plaques in the arteries (atherosclerosis) is the most common cause of coronary artery disease. Risk factors include a poor diet, lack of exercise, obesity and smoking. Healthy lifestyle choices can help lower the risk of atherosclerosis.

Causes of irregular heartbeats (arrhythmias)

Common causes of arrhythmias or conditions that can lead to them include:

  • Cardiomyopathy
  • Coronary artery disease
  • Diabetes
  • Drug misuse
  • Emotional stress
  • Excessive use of alcohol or caffeine
  • Heart problem present at birth (congenital heart defects)
  • High blood pressure
  • Smoking
  • Heart valve disease
  • Use of certain medications, including those bought without a prescription, and herbs and supplements

Causes of congenital heart defects

A congenital heart defect develops while a baby is growing in the womb. A congenital heart defect forms as the baby’s heart develops, about a month after conception. Congenital heart defects change the flow of blood in the heart. Some medical conditions, medications and genes increase the risk of congenital heart defects.

Causes of a thickened or enlarged heart muscle (cardiomyopathy)

The cause of cardiomyopathy depends on the type:

  • Dilated cardiomyopathy. The cause of this most common type of cardiomyopathy often is unknown. It may be passed down through families (inherited). Dilated cardiomyopathy typically starts in the heart’s main pumping chamber (left ventricle). Many things can cause damage to the left ventricle, including heart attacks, infections, toxins and some drugs, including cancer medicines.
  • Hypertrophic cardiomyopathy. This type is usually passed down through families (inherited).
  • Restrictive cardiomyopathy. This is the least common type of cardiomyopathy. It can occur for no known reason. Sometimes it’s caused by a buildup of protein called amyloid in the heart (cardiac amyloidosis) or connective tissue disorders.

Causes of heart infection

A heart infection, such as endocarditis, occurs when germs reach the heart or heart valves. The most common causes of heart infections are:

  • Bacteria
  • Viruses
  • Parasites

Causes of heart valve disease

Many things can cause diseases of the heart valves. Some people are born with heart valve disease (congenital heart valve disease). Heart valve disease may also be caused by conditions such as:

  • Rheumatic fever
  • Infections (infectious endocarditis)
  • Connective tissue disorders

Risk factors

Risk factors for heart disease include:

  • Age. Growing older increases the risk of damaged and narrowed arteries and a weakened or thickened heart muscle.
  • Sex. Men are generally at greater risk of heart disease. The risk for women increases after menopause.
  • Family history. A family history of heart disease increases the risk of coronary artery disease, especially if a parent developed it at an early age (before age 55 for a male relative, such as your brother or father, and 65 for a female relative, such as your mother or sister).
  • Smoking. If you smoke, quit. Substances in tobacco smoke damage the arteries. Heart attacks are more common in smokers than in nonsmokers. If you need help quitting, talk to your health care provider about strategies that can help.
  • Unhealthy diet. Diets high in fat, salt, sugar and cholesterol have been linked to heart disease.
  • High blood pressure. Uncontrolled high blood pressure can cause the arteries to become hard and thick. These changes interrupt blood flow to the heart and body.
  • High cholesterol. Having high cholesterol increases the risk of atherosclerosis. Atherosclerosis has been linked to heart attacks and strokes.
  • Diabetes. Diabetes increases the risk of heart disease. Obesity and high blood pressure increase the risk of diabetes and heart disease.
  • Obesity. Excess weight typically worsens other heart disease risk factors.
  • Lack of exercises. Being inactive (sedentary lifestyle) is associated with many forms of heart disease and some of its risk factors, too.
  • Stress. Unrelieved stress may damage the arteries and worsen other risk factors for heart disease.
  • Poor dental health. It’s important to brush and floss your teeth and gums often. Also get regular dental checkups. Unhealthy teeth and gums makes it easier for germs to enter the bloodstream and travel to the heart. This can cause endocarditis.


Complications of heart disease include:

  • Heart failure. This is one of the most common complications of heart disease. Heart failure occurs when the heart can’t pump enough blood to meet the body’s needs.
  • Heart attack. A heart attack may occur if a blood clot is stuck in a blood vessel that goes to the heart.
  • Stroke. The risk factors that lead to heart disease can also lead to an ischemic stroke. This type of stroke happens when the arteries to the brain are narrowed or blocked. Too little blood reaches the brain. A stroke is a medical emergency — brain tissue begins to die within just a few minutes of a stroke.
  • Aneurysm. An aneurysm is a bulge in the wall of an artery. If an aneurysm bursts, you may have life-threatening internal bleeding.
  • Peripheral artery disease. In this condition, the arms or legs — usually the legs — don’t get enough blood. This causes symptoms, most notably leg pain when walking (claudication). Atherosclerosis can lead to peripheral artery disease.
  • Sudden cardiac arrest. Sudden cardiac arrest is the sudden loss of heart function, breathing and consciousness. It’s usually due to a problem with the heart’s electrical system. Sudden cardiac arrest is a medical emergency. If not treated immediately, it results in sudden cardiac death.


The same lifestyle changes used to manage heart disease may also help prevent it. Try these heart-healthy tips:

  • Don’t smoke.
  • Eat a diet that’s low in salt and saturated fat.
  • Exercise at least 30 minutes a day on most days of the week.
  • Maintain a healthy weight.
  • Reduce and manage stress.
  • Control high blood pressure, high cholesterol and diabetes.
  • Get good sleep. Adults should aim for 7 to 9 hours daily.

Aortic valve disease is a type of heart valve disease.


Aortic valve disease is a type of heart valve disease. In aortic valve disease, the valve between the lower left heart chamber (left ventricle) and the main artery to the body (aorta) doesn’t work properly.

The aortic valve helps keep blood flowing in the correct direction through the heart. A damaged or diseased aortic valve can affect blood flow to the rest of the heart and body.

Aortic valve disease includes:

  • Aortic valve stenosis. The flaps (cusps) of the aortic valve become thick and stiff, or they fuse together. These problems cause the valve opening to become narrow. The narrowed valve reduces or blocks blood flow from the heart to the rest of the body.
  • Aortic valve regurgitation. The aortic valve doesn’t close properly, causing blood to flow backward into the left lower heart chamber (ventricle).

Aortic valve disease may be present at birth (congenital heart disease), or it may occur later in life due to other health conditions.

Treatment for aortic valve disease depends on the type and severity of disease. Some people may need surgery to repair or replace the aortic valve.


Some people with aortic valve disease may not notice symptoms for many years. Signs and symptoms of aortic valve disease may include:

  • Whooshing or swishing heart sound (heart murmur)
  • Chest pain or tightness
  • Dizziness
  • Fainting
  • Fatigue after activity or having less ability to be active
  • Irregular heartbeat
  • Shortness of breath, particularly during vigorous activity or when lying down
  • Not eating enough (mainly in children with aortic valve stenosis)
  • Not gaining enough weight (mainly in children with aortic valve stenosis)

When to see a doctor

If you’re having sudden chest pain, get emergency medical help.

Make an appointment with a health care provider if you have signs or symptoms of valve disease, such as shortness of breath, fatigue after activity, or sensations of a pounding or an irregular heartbeat. Sometimes the first signs of aortic valve disease are related to heart failure. See a health care provider if you have fatigue that doesn’t get better with rest, shortness of breath, and swollen ankles and feet, which are common symptoms of heart failure.

Aortic valve disease may be caused by a heart defect present at birth (congenital heart defect). Other causes of aortic valve disease later in life include:

  • Age-related changes to the heart
  • Infections
  • High blood pressure
  • Injury to the heart

To better understand the causes of aortic valve disease, it may be helpful to know how the heart valves typically work.

The heart has four valves that keep blood flowing in the correct direction. These valves are:

  • Aortic valve
  • Mitral valve
  • Tricuspid valve
  • Pulmonary valve

Each valve has flaps (cusps or leaflets) that open and close once during each heartbeat. Sometimes, a valve doesn’t open or close properly. This can reduce or block blood flow through the heart to the rest of the body.

In aortic valve disease, the valve between the lower left heart chamber (left ventricle) and the body’s main artery (aorta) doesn’t work properly. The valve may be thickened and stiff (stenosis) or it may not close properly, causing blood to flow backward.

Risk factors

Many things can raise the risk of aortic valve disease, including:

  • Older age. Calcium deposits can build up on the aortic valve as people age, causing the aortic valve to stiffen and become narrow.
  • Heart valve problems present at birth (congenital heart defects). Some people are born with a missing, extra or fused valve flap (cusp), increasing the risk of aortic valve regurgitation.
  • Rheumatic fever. This complication of strep throat can cause aortic stenosis, a type of valve disease. If you have heart valve disease due to rheumatic fever, it’s called rheumatic heart disease. If not, it’s called nonrheumatic heart disease.
  • Inflammation of the lining of the heart’s chambers and valves (endocarditis). This life-threatening condition is usually caused by infection. It can damage the aortic valve.
  • History of radiation therapy to the chest. Some types of cancer are treated with radiation therapy. Symptoms of heart valve disease may not be noticed until many years after radiation therapy is received.
  • Other health conditions. Chronic kidney disease, lupus and Marfan syndrome, a connective tissue disease, can increase the risk of aortic stenosis or regurgitation.


Potential complications of aortic valve disease may include:

  • Blood clots
  • Stroke
  • Heart failure
  • Heart rhythm problems (heart arrhythmias)
  • Death due to sudden cardiac arrest

Proper diagnosis and treatment can help reduce the risk of complications.

Alzheimer’s disease is a brain disorder that gets worse over time.


Alzheimer’s disease is a brain disorder that gets worse over time. It’s characterized by changes in the brain that lead to deposits of certain proteins. Alzheimer’s disease causes the brain to shrink and brain cells to eventually die. Alzheimer’s disease is the most common cause of dementia — a gradual decline in memory, thinking, behavior and social skills. These changes affect a person’s ability to function.

About 6.5 million people in the United States age 65 and older live with Alzheimer’s disease. Among them, more than 70% are 75 years old and older. Of the about 55 million people worldwide with dementia, 60% to 70% are estimated to have Alzheimer’s disease.

The early signs of the disease include forgetting recent events or conversations. Over time, it progresses to serious memory problems and loss of the ability to perform everyday tasks.

Medicines may improve or slow the progression of symptoms. Programs and services can help support people with the disease and their caregivers.

There is no treatment that cures Alzheimer’s disease. In advanced stages, severe loss of brain function can cause dehydration, malnutrition or infection. These complications can result in death.


Memory loss is the key symptom of Alzheimer’s disease. Early signs include difficulty remembering recent events or conversations. But memory gets worse and other symptoms develop as the disease progresses.

At first, someone with the disease may be aware of having trouble remembering things and thinking clearly. As symptoms get worse, a family member or friend may be more likely to notice the issues.

Brain changes associated with Alzheimer’s disease lead to growing trouble with:


Everyone has memory lapses at times, but the memory loss associated with Alzheimer’s disease persists and gets worse. Over time, memory loss affects the ability to function at work or at home.

People with Alzheimer’s disease may:

  • Repeat statements and questions over and over.
  • Forget conversations, appointments or events.
  • Misplace items, often putting them in places that don’t make sense.
  • Get lost in places they used to know well.
  • Eventually forget the names of family members and everyday objects.
  • Have trouble finding the right words for objects, expressing thoughts or taking part in conversations.

Thinking and reasoning

Alzheimer’s disease causes difficulty concentrating and thinking, especially about abstract concepts such as numbers.

Doing more than one task at once is especially difficult. It may be challenging to manage finances, balance checkbooks and pay bills on time. Eventually, a person with Alzheimer’s disease may be unable to recognize and deal with numbers.

Making judgments and decisions

Alzheimer’s disease causes a decline in the ability to make sensible decisions and judgments in everyday situations. For example, a person may make poor choices in social settings or wear clothes for the wrong type of weather. It may become harder for someone to respond to everyday problems. For example, the person may not know how to handle food burning on the stove or decisions when driving.

Planning and performing familiar tasks

Routine activities that require completing steps in order become a struggle. This may include planning and cooking a meal or playing a favorite game. Eventually, people with advanced Alzheimer’s disease forget how to do basic tasks such as dressing and bathing.

Changes in personality and behavior

Brain changes that occur in Alzheimer’s disease can affect moods and behaviors. Problems may include the following:

  • Depression.
  • Loss of interest in activities.
  • Social withdrawal.
  • Mood swings.
  • Distrust in others.
  • Anger or aggression.
  • Changes in sleeping habits.
  • Wandering.
  • Loss of inhibitions.
  • Delusions, such as believing something has been stolen.

Preserved skills

Despite major changes to memory and skills, people with Alzheimer’s disease are able to hold on to some skills even as symptoms get worse. Preserved skills may include reading or listening to books, telling stories, sharing memories, singing, listening to music, dancing, drawing, or doing crafts.

These skills may be preserved longer because they’re controlled by parts of the brain affected later in the course of the disease.

When to see a doctor

A number of conditions can result in memory loss or other dementia symptoms. Some of those conditions can be treated. If you are concerned about your memory or other thinking skills, talk to your health care provider.

If you are concerned about thinking skills you observe in a family member or friend, talk about your concerns and ask about going together to talk to a provider.


The exact causes of Alzheimer’s disease aren’t fully understood. But at a basic level, brain proteins fail to function as usual. This disrupts the work of brain cells, also called neurons, and triggers a series of events. The neurons become damaged and lose connections to each other. They eventually die.

Scientists believe that for most people, Alzheimer’s disease is caused by a combination of genetic, lifestyle and environmental factors that affect the brain over time. In less than 1% of cases, Alzheimer’s is caused by specific genetic changes that almost guarantee a person will develop the disease. In these cases, the disease usually begins in middle age.

The development of the disease begins years before the first symptoms. The damage most often starts in the region of the brain that controls memory. The loss of neurons spreads in a somewhat predictable pattern to other regions of the brain. By the late stage of the disease, the brain has shrunk significantly.

Researchers trying to understand the cause of Alzheimer’s disease are focused on the role of two proteins:

  • Plaques. Beta-amyloid is a fragment of a larger protein. When these fragments clump together, they appear to have a toxic effect on neurons and to disrupt communication between brain cells. These clumps form larger deposits called amyloid plaques, which also include other cellular debris.
  • Tangles. Tau proteins play a part in a brain cell’s internal support and transport system to carry nutrients and other essential materials. In Alzheimer’s disease, tau proteins change shape and organize into structures called neurofibrillary tangles. The tangles disrupt the transport system and cause damage to cells.

Risk factors


Increasing age is the greatest known risk factor for Alzheimer’s disease. Alzheimer’s isn’t a part of typical aging. But as you grow older, the chances of developing it increases.

One study found that every year there were four new diagnoses per 1,000 people ages 65 to 74. Among people ages 75 to 84, there were 32 new diagnoses per 1,000 people. For those 85 and older, there were 76 new diagnoses per 1,000 people.

Family history and genetics

The risk of developing Alzheimer’s is somewhat higher if a first-degree relative — your parent or sibling — has the disease. Just how genes among families affect the risk is largely unexplained, and the genetic factors are likely complex.

A better understood genetic factor is a form of the apolipoprotein E (APOE) gene. A form of the gene, APOE e4, increases the risk of Alzheimer’s disease. About 25% to 30% of the population carries an APOE e4 allele. But not everyone with this form of the gene develops the disease.

Scientists have found rare changes in three genes that virtually guarantee a person who inherits one of them will develop Alzheimer’s. But these changes account for less than 1% of people with Alzheimer’s disease.

Down syndrome

Many people with Down syndrome develop Alzheimer’s disease. This is likely related to having three copies of chromosome 21. Chromosome 21 is the gene involved in the production of the protein that leads to the creation of beta-amyloid. Beta-amyloid fragments can become plaques in the brain. Symptoms tend to appear 10 to 20 years earlier in people with Down syndrome than they do for the general population.


Overall there are more women with the disease because they tend to live longer than men.

Mild cognitive impairment

Someone with mild cognitive impairment (MCI) has a decline in memory or other thinking skills that is greater than usual for the person’s age. But the decline doesn’t prevent the person from functioning in social or work environments.

However, people with MCI have a significant risk of developing dementia. When MCI affects mainly memory, the condition is more likely to progress to dementia due to Alzheimer’s disease. A diagnosis of MCI offers people the chance to put a greater focus on healthy lifestyle changes and to come up with strategies to make up for memory loss. They also can schedule regular health care appointments to monitor symptoms.

Head trauma

Several large studies found that people age 50 years or older who had a traumatic brain injury (TBI) had an increased risk of dementia and Alzheimer’s disease. The risk is even higher in people with more-severe and multiple TBIs. Some studies found that the risk may be greatest within the first six months to two years after the injury.

Air pollution

Studies in animals have found that air pollution particulates can speed the breakdown of the nervous system. And human studies have found that air pollution exposure — especially from traffic exhaust and burning wood — is linked to a greater dementia risk.

Excessive alcohol consumption

Drinking large amounts of alcohol has long been known to cause brain changes. Several large studies and reviews found that alcohol use disorders were linked to an increased risk of dementia — early-onset dementia in particular.

Poor sleep patterns

Research has shown that poor sleep patterns, such as trouble falling asleep or staying asleep, are linked to an increased risk of Alzheimer’s disease.

Lifestyle and heart health

Research has shown that the same risk factors associated with heart disease also may increase the risk of dementia. It’s unclear if these factors increase risk of dementia by worsening Alzheimer’s changes in the brain or by leading to brain vascular changes. They include:

  • Lack of exercise.
  • Obesity.
  • Smoking or exposure to secondhand smoke.
  • High blood pressure.
  • High cholesterol.
  • Poorly controlled type 2 diabetes.

These factors can all be modified. Therefore, changing lifestyle habits can to some degree alter your risk. For example, regular exercise and a healthy low-fat diet rich in fruits and vegetables are related to a lower risk of Alzheimer’s disease.

Lifelong learning and social engagement

Studies have found that socializing and engaging in activities that stimulate the mind throughout life can lower the risk of Alzheimer’s disease. Low education levels — less than a high school education — appear to be a risk factor for Alzheimer’s disease.


Alzheimer’s symptoms such as memory loss, language loss, impaired judgment and other brain changes can make it harder to manage other health conditions. A person with Alzheimer’s disease may not be able to:

  • Tell someone about being in pain.
  • Explain symptoms of another illness.
  • Follow a treatment plan.
  • Explain medicine side effects.

As Alzheimer’s disease moves into its last stages, brain changes begin to affect physical functions. The changes can affect the ability to swallow, balance, and control bowel and bladder movements. These effects can lead to other health problems such as:

  • Inhaling food or liquid into the lungs.
  • Flu, pneumonia and other infections.
  • Falls.
  • Fractures.
  • Bedsores.
  • Poor nutrition or dehydration.
  • Constipation or diarrhea.
  • Dental problems such as mouth sores or tooth decay.


Alzheimer’s disease is not a preventable condition. However, a number of lifestyle risk factors can be modified.

Evidence suggests that taking steps to reduce the risk of cardiovascular disease may also lower your risk of developing dementia.

To follow heart-healthy lifestyle choices that may reduce the risk of dementia:

  • Exercise regularly.
  • Eat a diet of fresh produce, healthy oils and foods low in saturated fat, such as a Mediterranean diet.
  • Follow treatment guidelines to manage high blood pressure, diabetes and high cholesterol.
  • If you smoke, ask your health care provider for help to quit.

One large, long-term study done in Finland found that making lifestyle changes helped reduce cognitive decline among people who were at risk of dementia. Those in the study were given individual and group sessions that focused on diet, exercise and social activities.

In another study done in Australia, people at risk of dementia were given coaching sessions on diet, exercise and other lifestyle changes. They had better results on cognitive tests after one, two and three years compared to people who didn’t receive the coaching.

Other studies have shown that staying engaged mentally and socially is linked to preserved thinking skills later in life and a lower risk of Alzheimer’s disease. This includes going to social events, reading, dancing, playing board games, creating art, playing an instrument and other activities.

A brain tumor is a growth of cells in the brain or near it.


A brain tumor is a growth of cells in the brain or near it. Brain tumors can happen in the brain tissue. Brain tumors also can happen near the brain tissue. Nearby locations include nerves, the pituitary gland, the pineal gland, and the membranes that cover the surface of the brain.

Brain tumors can begin in the brain. These are called primary brain tumors. Sometimes, cancer spreads to the brain from other parts of the body. These tumors are secondary brain tumors, also called metastatic brain tumors.

Many different types of primary brain tumors exist. Some brain tumors aren’t cancerous. These are called noncancerous brain tumors or benign brain tumors. Noncancerous brain tumors may grow over time and press on the brain tissue. Other brain tumors are brain cancers, also called malignant brain tumors. Brain cancers may grow quickly. The cancer cells can invade and destroy the brain tissue.

Brain tumors range in size from very small to very large. Some brain tumors are found when they are very small because they cause symptoms that you notice right away. Other brain tumors grow very large before they’re found. Some parts of the brain are less active than others. If a brain tumor starts in a part of the brain that’s less active, it might not cause symptoms right away. The brain tumor size could become quite large before the tumor is detected.

Brain tumor treatment options depend on the type of brain tumor you have, as well as its size and location. Common treatments include surgery and radiation therapy.


There are many types of brain tumors. The type of brain tumor is based on the kind of cells that make up the tumor. Special lab tests on the tumor cells can give information about the cells. Your health care team uses this information to figure out the type of brain tumor.

Some types of brain tumors usually aren’t cancerous. These are called noncancerous brain tumors or benign brain tumors. Some types of brain tumors usually are cancerous. These types are called brain cancers or malignant brain tumors. Some brain tumor types can be benign or malignant.

Benign brain tumors tend to be slow-growing brain tumors. Malignant brain tumors tend to be fast-growing brain tumors.

Types of brain tumors include:

  • Gliomas and related brain tumors. Gliomas are growths of cells that look like glial cells. The glial cells surround and support nerve cells in the brain tissue. Types of gliomas and related brain tumors include astrocytoma, glioblastoma, oligodendroglioma and ependymoma. Gliomas can be benign, but most are malignant. Glioblastoma is the most common type of malignant brain tumor.
  • Choroid plexus tumors. Choroid plexus tumors start in cells that make the fluid that surrounds the brain and spinal cord. This fluid is called cerebrospinal fluid. Choroid plexus tumors are located in the fluid-filled cavities in the brain, called the ventricles. Choroid plexus tumors can be benign or malignant. Choroid plexus carcinoma is the malignant form of this type of brain tumor. It’s more common in children.
  • Embryonal tumors. Embryonal tumors begin in cells that are left over from fetal development. The cells, called embryonal cells, stay in the brain after birth. Embryonal tumors are malignant brain tumors that happen most often in babies and young children. The most common type of embryonal tumor is medulloblastoma. It’s usually located in the lower back part of the brain, called the cerebellum.
  • Germ cell tumors. Germ cell tumors start in reproductive cells, called germ cells, that go on to become the sperm and egg cells. Germ cells are mostly in the ovaries and testicles. But sometimes they’re in other parts of the body, including the brain. When germ cell tumors happen in the brain, they’re often located near the pineal gland or the pituitary gland. Germ cell tumors are mostly benign. They’re more common in children.
  • Pineal tumors. Pineal tumors start in and around the brain’s pineal gland. The pineal gland is located in the center of the brain. It makes a hormone called melatonin that helps with sleep. Pineal tumors can be benign or malignant. Pineoblastoma is a malignant type of pineal tumor that’s most common in children.
  • Meningiomas. Meningiomas are brain tumors that start in the membranes around the brain and spinal cord. Meningiomas are usually benign, but sometimes they can be malignant. Meningiomas are the most common type of benign brain tumor.
  • Nerve tumors. Nerve tumors are growths that happen in and around nerves. The most common type that happens in the head is acoustic neuroma, also called schwannoma. This benign tumor is located on the main nerve that connects the inner ear to the brain.
  • Pituitary tumors. Brain tumors can begin in and around the pituitary gland. This small gland is located near the base of the brain. Most tumors that happen in and around the pituitary gland are benign. Pituitary tumors happen in the pituitary gland itself. Craniopharyngioma is a type of brain tumor that happens near the pituitary gland.
  • Other brain tumors. Many other types of rare tumors can happen in and around the brain. Tumors can start in the muscles, blood vessels and connective tissue around the brain. Tumors can form in the bones of the skull. Malignant brain tumors can start from the germ-fighting immune system cells in the brain. This type of brain cancer is called primary central nervous system lymphoma.


The signs and symptoms of a brain tumor depend on the brain tumor’s size and location. Symptoms also might depend on how fast the brain tumor is growing, which is also called the tumor grade.

General signs and symptoms caused by brain tumors may include:

  • Headache or pressure in the head that is worse in the morning.
  • Headaches that happen more often and seem more severe.
  • Headaches that are sometimes described as tension headaches or migraines.
  • Nausea or vomiting.
  • Eye problems, such as blurry vision, seeing double or losing sight on the sides of your vision.
  • Losing feeling or movement in an arm or a leg.
  • Trouble with balance.
  • Speech problems.
  • Feeling very tired.
  • Confusion in everyday matters.
  • Memory problems.
  • Having trouble following simple commands.
  • Personality or behavior changes.
  • Seizures, especially if there is no history of seizures.
  • Hearing problems.
  • Dizziness or a sense that the world is spinning, also called vertigo.
  • Feeling very hungry and gaining weight.

Brain tumors that aren’t cancerous tend to cause symptoms that develop slowly. Noncancerous brain tumors also are called benign brain tumors. They might cause subtle symptoms that you don’t notice at first. The symptoms might get worse over months or years.

Cancerous brain tumors cause symptoms that get worse quickly. Cancerous brain tumors also are called brain cancers or malignant brain tumors. They cause symptoms that come on suddenly. They get worse in a matter of days or weeks.

Brain tumor headaches

Headaches are the most common symptom of brain tumors. Headaches happen in about half of people with brain tumors. Headaches can happen if a growing brain tumor presses on healthy cells around it. Or a brain tumor can cause swelling in the brain that increases pressure in the head and leads to a headache.

Headache pain caused by brain tumors is often worse when you wake up in the morning. But it can happen at any time. Some people have headaches that wake them from sleep. Brain tumor headaches tend to cause pain that’s worse when coughing or straining. People with brain tumors most often report that the headache feels like a tension headache. Some people say the headache feels like a migraine.

Brain tumors in the back of the head might cause a headache with neck pain. If the brain tumor happens in the front of the head, the headache might feel like eye pain or sinus pain.

Brain tumor symptoms by location

he main part of the brain is called the cerebrum. Brain tumors in different parts of the cerebrum might cause different symptoms.

  • Brain tumors in the front of the brain. The frontal lobes are in the front of the brain. They control thinking and movement. Frontal lobe brain tumors might cause balance problems and trouble walking. There might be personality changes, such as forgetfulness and lack of interest in usual activities. Sometimes family members notice that the person with the brain tumor seems different.
  • Brain tumors in the middle of the brain. The parietal lobes are in the upper middle part of the brain. They help process information about touch, taste, smell, vision and hearing. Parietal lobe brain tumors can cause problems related to the senses. Examples include vision problems and hearing problems.
  • Brain tumors in the back of the brain. The occipital lobes are in the back of the brain. They control vision. Occipital lobe brain tumors can cause vision loss.
  • Brain tumors in the lower part of the brain. The temporal lobes are on the sides of the brain. They process memories and senses. Temporal lobe brain tumors can cause memory problems. They might cause someone to see, taste or smell something that isn’t there. Sometimes the taste or smell is unpleasant or unusual.


Brain tumors that begin in the brain

Brain tumors that start as a growth of cells in the brain are called primary brain tumors. They might start right in the brain or in the tissue nearby. Nearby tissue might include the membranes that cover the brain, called meninges. Brain tumors also can happen in nerves, the pituitary gland and the pineal gland.

Brain tumors happen when cells in or near the brain get changes in their DNA. A cell’s DNA holds the instructions that tell the cell what to do. The changes tell the cells to grow quickly and continue living when healthy cells would die as part of their natural life cycle. This makes a lot of extra cells in the brain. The cells can form a growth called a tumor.

It’s not clear what causes the DNA changes that lead to brain tumors. For many people with brain tumors, the cause is never known. Sometimes parents pass DNA changes to their children. The changes can increase the risk of having a brain tumor. These hereditary brain tumors are rare. If you have a family history of brain tumors, talk about it with your health care provider. You might consider meeting with a health care provider trained in genetics to understand whether your family history increases your risk of having a brain tumor.

When brain tumors happen in children, they’re likely to be primary brain tumors. In adults, brain tumors are more likely to be cancer that started somewhere else and spread to the brain.

Cancer that spreads to the brain

Secondary brain tumors happen when cancer starts somewhere else and spreads to the brain. When cancer spreads, it’s called metastatic cancer.

Any cancer can spread to the brain, but common types include:

  • Breast cancer.
  • Colon cancer.
  • Kidney cancer.
  • Lung cancer.
  • Melanoma.

It’s not clear why some cancers spread to the brain and others are more likely to spread to other places.

Secondary brain tumors most often happen in people who have a history of cancer. Rarely, a brain tumor may be the first sign of cancer that began somewhere else in the body.

In adults, secondary brain tumors are far more common than are primary brain tumors.

Risk factors

In most people with primary brain tumors, the cause isn’t clear. But doctors have identified some factors that may raise the risk.

Risk factors include:

  • Age. Brain tumors can happen at any age, but they happen most often in older adults. Some brain tumors mostly affect adults. Some brain tumors happen most often in children.
  • Race. Anyone can get a brain tumor. But some types of brain tumors are more common in people of certain races. For example, gliomas are more common in white people. Meningiomas are more common in Black people.
  • Exposure to radiation. People who have been exposed to a strong type of radiation have an increased risk of brain tumor. This strong radiation is called ionizing radiation. The radiation is strong enough to cause DNA changes in the body’s cells. The DNA changes can lead to tumors and cancers. Examples of ionizing radiation include radiation therapy used to treat cancer and radiation exposure caused by atomic bombs.Low-level radiation from everyday objects isn’t linked to brain tumors. Low levels of radiation include the energy that comes from cellphones and radio waves. There is no convincing evidence that using cellphones causes brain tumors. But more studies are happening to make sure.
  • Inherited syndromes that increase the risk of brain tumor. Some DNA changes that increase the risk of brain tumor run in families. Examples include the DNA changes that cause neurofibromatosis 1 and 2, tuberous sclerosis, Lynch syndrome, Li-Fraumeni syndrome, Von Hippel-Lindau disease, familial adenomatous polyposis, Cowden syndrome, and Gorlin syndrome.


There’s no way to prevent brain tumors. If you get a brain tumor, you didn’t do anything to cause it.

People with an increased risk of brain tumor might consider screening tests. Screening isn’t brain tumor prevention. But screening might help find a brain tumor when it’s small and treatment is more likely to be successful.

If you have a family history of brain tumor or inherited syndromes that increase the risk of brain tumor, talk about it with your health care provider. You might consider meeting with a genetic counselor or other health care provider trained in genetics. This person can help you understand your risk and ways to manage it. For example, you might consider brain tumor screening tests. Testing might include an imaging test or a neurological exam to test your vision, hearing, balance, coordination and reflexes.

Rickets is the softening and weakening of bones in children, usually because of an vitamin D deficiency


Rickets is the softening and weakening of bones in children, usually because of an extreme and prolonged vitamin D deficiency. Rare inherited problems also can cause rickets.

Vitamin D helps your child’s body absorb calcium and phosphorus from food. Not enough vitamin D makes it difficult to maintain proper calcium and phosphorus levels in bones, which can cause rickets.

Adding vitamin D or calcium to the diet generally corrects the bone problems associated with rickets. When rickets is due to another underlying medical problem, your child may need additional medications or other treatment. Some skeletal deformities caused by rickets may require corrective surgery.

Rare inherited disorders related to low levels of phosphorus, the other mineral component in bone, may require other medications.


Signs and symptoms of rickets can include:

  • Delayed growth
  • Delayed motor skills
  • Pain in the spine, pelvis and legs
  • Muscle weakness

Because rickets softens the areas of growing tissue at the ends of a child’s bones (growth plates), it can cause skeletal deformities such as:

  • Bowed legs or knock knees
  • Thickened wrists and ankles
  • Breastbone projection

When to see a doctor

Talk to your doctor if your child develops bone pain, muscle weakness or obvious skeletal deformities.


Your child’s body needs vitamin D to absorb calcium and phosphorus from food. Rickets can occur if your child’s body doesn’t get enough vitamin D or if his or her body has problems using vitamin D properly. Occasionally, not getting enough calcium or lack of calcium and vitamin D can cause rickets.

Lack of vitamin D

Children who don’t get enough vitamin D from these two sources can develop a deficiency:

  • Sunlight. Your child’s skin produces vitamin D when it’s exposed to sunlight. But children in developed countries tend to spend less time outdoors. They’re also more likely to use sunscreen, which blocks the sun’s rays that trigger the skin’s production of vitamin D.
  • Food. Fish oil, egg yolks and fatty fish such as salmon and mackerel contain vitamin D. Vitamin D has also been added to some foods and beverages, such as milk, cereal and some fruit juices.

Problems with absorption

Some children are born with or develop medical conditions that affect the way their bodies absorb vitamin D. Some examples include:

  • Celiac disease
  • Inflammatory bowel disease
  • Cystic fibrosis
  • Kidney problems

Risk factors

Factors that can increase a child’s risk of rickets include:

  • Dark skin. Dark skin has more of the pigment melanin, which lowers the skin’s ability to produce vitamin D from sunlight.
  • Mother’s vitamin D deficiency during pregnancy. A baby born to a mother with severe vitamin D deficiency can be born with signs of rickets or develop them within a few months after birth.
  • Northern latitudes. Children who live in geographical locations where there is less sunshine are at higher risk of rickets.
  • Premature birth. Babies born before their due dates tend have lower levels of vitamin D because they had less time to receive the vitamin from their mothers in the womb.
  • Medications. Certain types of anti-seizure medications and antiretroviral medications, used to treat HIV infections, appear to interfere with the body’s ability to use vitamin D.
  • Exclusive breast-feeding. Breast milk doesn’t contain enough vitamin D to prevent rickets. Babies who are exclusively breast-fed should receive vitamin D drops.


Left untreated, rickets can lead to:

  • Failure to grow
  • An abnormally curved spine
  • Bone deformities
  • Dental defects
  • Seizures


Exposure to sunlight provides the best source of vitamin D. During most seasons, 10 to 15 minutes of exposure to the sun near midday is enough. However, if you’re dark-skinned, if it’s winter or if you live in northern latitudes, you might not be able to get enough vitamin D from sun exposure.

In addition, because of skin cancer concerns, infants and young children, especially, are warned to avoid direct sun or to always wear sunscreen and protective clothing.

To prevent rickets, make sure your child eats foods that contain vitamin D naturally — fatty fish such as salmon and tuna, fish oil and egg yolks — or that have been fortified with vitamin D, such as:

  • Infant formula
  • Cereal
  • Bread
  • Milk, but not foods made from milk, such as some yogurts and cheese
  • Orange juice

Check labels to determine the vitamin D content of fortified foods.

If you’re pregnant, ask your doctor about taking vitamin D supplements.

Guidelines recommend that all infants should receive 400 IU a day of vitamin D. Because human milk contains only a small amount of vitamin D, infants who are exclusively breast-fed should receive supplemental vitamin D daily. Some bottle-fed infants may also need vitamin D supplements if they aren’t receiving enough from their formula.

Hypercalcemia is a condition in which calcium level in your blood is above normal.


Hypercalcemia is a condition in which the calcium level in your blood is above normal. Too much calcium in your blood can weaken your bones, create kidney stones, and interfere with how your heart and brain work.

Hypercalcemia is usually a result of overactive parathyroid glands. These four tiny glands are situated in the neck, near the thyroid gland. Other causes of hypercalcemia include cancer, certain other medical disorders, some medications, and taking too much of calcium and vitamin D supplements.

Signs and symptoms of hypercalcemia range from nonexistent to severe. Treatment depends on the cause.


You might not have signs or symptoms if your hypercalcemia is mild. More-severe cases produce signs and symptoms related to the parts of your body affected by the high calcium levels in your blood. Examples include:

  • Kidneys. Excess calcium makes your kidneys work harder to filter it. This can cause excessive thirst and frequent urination.
  • Digestive system. Hypercalcemia can cause stomach upset, nausea, vomiting and constipation.
  • Bones and muscles. In most cases, the excess calcium in your blood was leached from your bones, which weakens them. This can cause bone pain and muscle weakness.
  • Brain. Hypercalcemia can interfere with how your brain works, resulting in confusion, lethargy and fatigue. It can also cause depression.
  • Heart. Rarely, severe hypercalcemia can interfere with your heart function, causing palpitations and fainting, indications of cardiac arrhythmia, and other heart problems.

When to see a doctor

Contact your doctor if you develop signs and symptoms that might indicate hypercalcemia, such as being extremely thirsty, urinating frequently and having abdominal pain.


Besides building strong bones and teeth, calcium helps muscles contract and nerves transmit signals. Normally, if there isn’t enough calcium in your blood, your parathyroid glands secrete a hormone that triggers:

  • Your bones to release calcium into your blood
  • Your digestive tract to absorb more calcium
  • Your kidneys to excrete less calcium and activate more vitamin D, which plays a vital role in calcium absorption

This delicate balance between too little calcium in your blood and hypercalcemia can be disrupted by a variety of factors. Hypercalcemia is caused by:

  • Overactive parathyroid glands (hyperparathyroidism). This most common cause of hypercalcemia can stem from a small, noncancerous (benign) tumor or enlargement of one or more of the four parathyroid glands.
  • Cancer. Lung cancer and breast cancer, as well as some blood cancers, can increase your risk of hypercalcemia. Spread of cancer (metastasis) to your bones also increases your risk.
  • Other diseases. Certain diseases, such as tuberculosis and sarcoidosis, can raise blood levels of vitamin D, which stimulates your digestive tract to absorb more calcium.
  • Hereditary factors. A rare genetic disorder known as familial hypocalciuric hypercalcemia causes an increase of calcium in your blood because of faulty calcium receptors in your body. This condition doesn’t cause symptoms or complications of hypercalcemia.
  • Immobility. People who have a condition that causes them to spend a lot of time sitting or lying down can develop hypercalcemia. Over time, bones that don’t bear weight release calcium into the blood.
  • Severe dehydration. A common cause of mild or transient hypercalcemia is dehydration. Having less fluid in your blood causes a rise in calcium concentrations.
  • Medications. Certain drugs — such as lithium, used to treat bipolar disorder — might increase the release of parathyroid hormone.
  • Supplements. Taking excessive amounts of calcium or vitamin D supplements over time can raise calcium levels in your blood above normal.


Hypercalcemia complications can include:

  • Osteoporosis. If your bones continue to release calcium into your blood, you can develop the bone-thinning disease osteoporosis, which could lead to bone fractures, spinal column curvature and loss of height.
  • Kidney stones. If your urine contains too much calcium, crystals might form in your kidneys. Over time, the crystals can combine to form kidney stones. Passing a stone can be extremely painful.
  • Kidney failure. Severe hypercalcemia can damage your kidneys, limiting their ability to cleanse the blood and eliminate fluid.
  • Nervous system problems. Severe hypercalcemia can lead to confusion, dementia and coma, which can be fatal.
  • Abnormal heart rhythm (arrhythmia). Hypercalcemia can affect the electrical impulses that regulate your heartbeat, causing your heart to beat irregularly.

A lipoma is a slow-growing, fatty lump that’s most often situated between your skin and the underlying muscle layer.


A lipoma is a slow-growing, fatty lump that’s most often situated between your skin and the underlying muscle layer. A lipoma, which feels doughy and usually isn’t tender, moves readily with slight finger pressure. Lipomas are usually detected in middle age. Some people have more than one lipoma.

A lipoma isn’t cancer and usually is harmless. Treatment generally isn’t necessary, but if the lipoma bothers you, is painful or is growing, you may want to have it removed.


Lipomas can occur anywhere in the body. They are typically:

  • Situated just under the skin. They commonly occur in the neck, shoulders, back, abdomen, arms and thighs.
  • Soft and doughy to the touch. They also move easily with slight finger pressure.
  • Generally small. Lipomas are typically less than 2 inches (5 centimeters) in diameter, but they can grow.
  • Sometimes painful. Lipomas can be painful if they grow and press on nearby nerves or if they contain many blood vessels.

When to see a doctor

A lipoma is rarely a serious medical condition. But if you notice a lump or swelling anywhere on your body, have it checked by your doctor.


The cause of lipomas isn’t fully understood. They tend to run in families, so genetic factors likely play a role in their development.

Risk factors

Several factors may increase your risk of developing a lipoma, including:

  • Being between 40 and 60 years old. Although lipomas can occur at any age, they’re most common in this age group.
  • Genetics. Lipomas tend to run in families.


To diagnose a lipoma, your doctor may perform:

  • A physical exam
  • A tissue sample removal (biopsy) for lab examination
  • An X-ray or other imaging test, such as an MRI or CT scan, if the lipoma is large, has unusual features or appears to be deeper than the fatty

There’s a very small chance that a lump resembling a lipoma may actually be a form of cancer called liposarcoma. Liposarcomas — cancerous tumors in fatty tissues — grow rapidly, don’t move under the skin and are usually painful. A biopsy or an MRI or CT scan is typically done if your doctor suspects liposarcoma

Preparing for your appointment

You’re likely to start by seeing your family doctor or primary doctor. You may then be referred to a doctor who specializes in skin disorders (dermatologist).

Here’s some information to help you get ready for your appointment.

What you can do

  • List your symptoms, including any that may seem unrelated to the reason for which you scheduled the appointment.
  • Make a list of medications, vitamins and supplements you’re taking.
  • List questions to ask your doctor.

Preparing a list of questions can help you make the most of your time with your doctor. For lipoma, some basic questions to ask include:

  • What caused this growth?
  • Is it cancer?
  • Do I need tests?
  • Will this lump always be there?
  • Can I have it removed?
  • What’s involved in removing it? Are there risks?
  • Is it likely to return, or am I likely to get another?
  • Do you have any brochures or other resources I can have? What websites do you recommend?

Don’t hesitate to ask other questions that occur to you.

What to expect from your doctor

Your doctor is likely to ask you questions, too, including:

  • When did you notice the lump?
  • Has it grown?
  • Have you had similar growths in the past?
  • Is the lump painful?
  • Have others in your family had similar lumps?

Rabies is a deadly virus spread to people from the saliva of infected animals.


Rabies is a deadly virus spread to people from the saliva of infected animals. The rabies virus is usually transmitted through a bite.

Animals most likely to transmit rabies in the United States include bats, coyotes, foxes, raccoons and skunks. In developing countries, stray dogs are the most likely to spread rabies to people.

Once a person begins showing signs and symptoms of rabies, the disease nearly always causes death. For this reason, anyone who may have a risk of contracting rabies should receive rabies vaccinations for protection.


The first symptoms of rabies may be very similar to those of the flu and may last for days.

Later signs and symptoms may include:

  • Fever
  • Headache
  • Nausea
  • Vomiting
  • Agitation
  • Anxiety
  • Confusion
  • Hyperactivity
  • Difficulty swallowing
  • Excessive salivation
  • Fear brought on by attempts to drink fluids because of difficulty swallowing water
  • Fear brought on by air blown on the face
  • Hallucinations
  • Insomnia
  • Partial paralysis

When to see a doctor

Seek immediate medical care if you’re bitten by any animal, or exposed to an animal suspected of having rabies. Based on your injuries and the situation in which the exposure happened, you and your doctor can decide whether you should receive treatment to prevent rabies.

Even if you aren’t sure whether you’ve been bitten, seek medical attention. For instance, a bat that flies into your room while you’re sleeping may bite you without waking you. If you awake to find a bat in your room, assume you’ve been bitten. Also, if you find a bat near a person who can’t report a bite, such as a small child or a person with a disability, assume that person has been bitten.


The rabies virus causes a rabies infection. The virus spreads through the saliva of infected animals. Infected animals can spread the virus by biting another animal or a person.

In rare cases, rabies can be spread when infected saliva gets into an open wound or the mucous membranes, such as the mouth or eyes. This could happen if an infected animal licked an open cut on your skin.

Animals that can transmit the rabies virus

Any mammal (an animal that suckles its young) can spread the rabies virus. The animals most likely to spread the rabies virus to people include:

  • Pets and farm animals
  • Cats
  • Cows
  • Dogs
  • Ferrets
  • Goats
  • Horses
  • Wild animals
  • Bats
  • Beavers
  • Coyotes
  • Foxes
  • Monkeys
  • Raccoons
  • Skunks
  • Woodchucks

In very rare cases, the virus has been spread to tissue and organ transplant recipients from an infected organ.

Risk factors

Factors that can increase your risk of rabies include:

  • Traveling or living in developing countries where rabies is more common
  • Activities that are likely to put you in contact with wild animals that may have rabies, such as exploring caves where bats live or camping without taking precautions to keep wild animals away from your campsite
  • Working as a veterinarian
  • Working in a laboratory with the rabies virus
  • Wounds to the head or neck, which may help the rabies virus travel to your brain more quickly


To reduce your risk of coming in contact with rabid animals:

  • Vaccinate your pets. Cats, dogs and ferrets can be vaccinated against rabies. Ask your veterinarian how often your pets should be vaccinated.
  • Keep your pets confined. Keep your pets inside and supervise them when outside. This will help keep your pets from coming in contact with wild animals.
  • Protect small pets from predators. Keep rabbits and other small pets, such as guinea pigs, inside or in protected cages so that they are safe from wild animals. These small pets can’t be vaccinated against rabies.
  • Report stray animals to local authorities. Call your local animal control officials or other local law enforcement to report stray dogs and cats.
  • Don’t approach wild animals. Wild animals with rabies may seem unafraid of people. It’s not normal for a wild animal to be friendly with people, so stay away from any animal that seems unafraid.
  • Keep bats out of your home. Seal any cracks and gaps where bats can enter your home. If you know you have bats in your home, work with a local expert to find ways to keep bats out.
  • Consider the rabies vaccine if you’re traveling or often around animals that may have rabies. If you’re traveling to a country where rabies is common and you’ll be there for an extended period of time, ask your doctor whether you should receive the rabies vaccine. This includes traveling to remote areas where medical care is difficult to find.

If you work as a veterinarian or work in a lab with the rabies virus, get the rabies vaccine.