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Patient-friendly health topic summaries from the US National Library of Medicine.
Your pituitary gland is a pea-sized gland at the base of your brain. The pituitary is the "master control gland" - it makes hormones that affect growth and the functions of other glands in the body. With pituitary disorders, you often…
Your gallbladder is a pear-shaped organ under your liver. It stores bile, a fluid made by your liver to digest fat. As your stomach and intestines digest food, your gallbladder releases bile through a tube called the common bile duct.…
Behcet's syndrome is a disease that involves vasculitis, which is inflammation of the blood vessels. It causes problems in many parts of the body. The most common symptoms are: • Sores in the mouth • Sores on the sex organs • Other…
Overactive bladder is a condition in which the bladder squeezes urine out at the wrong time. You may have overactive bladder if you have two or more of these symptoms: • You urinate eight or more times a day or two or more times at…
Dementia is a loss of mental functions that is severe enough to affect your daily life and activities. These functions include: • Memory • Language skills • Visual perception (your ability to make sense of what you see) • Problem…
Lymphoma is a cancer of a part of the immune system called the lymph system. There are many types of lymphoma. One type is Hodgkin disease. The rest are called non-Hodgkin lymphomas. Non-Hodgkin lymphomas begin when a type of white…
Conjunctivitis is the medical name for pink eye. It involves inflammation of the outer layer of the eye and inside of the eyelid. It can cause swelling, itching, burning, discharge, and redness. Causes include: • Bacterial or viral…
Cystic fibrosis (CF) is an inherited disease of the mucus and sweat glands. It affects mostly your lungs, pancreas, liver, intestines, sinuses, and sex organs. CF causes your mucus to be thick and sticky. The mucus clogs the lungs,…
Peripheral arterial disease (PAD) happens when there is a narrowing of the blood vessels outside of your heart. The cause of PAD is atherosclerosis. This happens when plaque builds up on the walls of the arteries that supply blood to…
Hives are red and sometimes itchy bumps on your skin. An allergic reaction to a drug or food usually causes them. Allergic reactions cause your body to release chemicals that can make your skin swell up in hives. People who have other…
Blood glucose, or blood sugar, is the main sugar found in your blood. It is your body's primary source of energy. It comes from the food you eat. Your body breaks down most of that food into glucose and releases it into your…
Cirrhosis is scarring of the liver. Scar tissue forms because of injury or long-term disease. Scar tissue cannot do what healthy liver tissue does - make protein, help fight infections, clean the blood, help digest food and store…
Your immune system protects you from disease and infection by attacking germs that get into your body, such as viruses and bacteria. Your immune system can tell that the germs aren't part of you, so it destroys them. If you have an…
Urinary incontinence (UI) is the loss of bladder control, or being unable to control urination. It is a common condition. It can range from being a minor problem to something that greatly affects your daily life. In any case, it can…
Nerves are like wires that carry messages back and forth between your brain and your body. Your peripheral nerves branch off from your brain and spinal cord and connect to all parts of your body, including your muscles and organs.…
Cancer is a disease in which abnormal cells in the body grow out of control and form a tumor. Ovarian cancer is a cancerous tumor that forms in the tissues of an ovary. The ovaries are a pair of female reproductive glands that make…
The optic nerve is a bundle of more than 1 million nerve fibers that carry visual messages. You have one connecting the back of each eye (your retina) to your brain. Damage to an optic nerve can cause vision loss. The type of vision…
Bronchitis is an inflammation of the bronchial tubes, the airways that carry air to your lungs. It causes a cough that often brings up mucus. It can also cause shortness of breath, wheezing, a low fever, and chest tightness. There are…
Congenital heart defects (CHDs) are problems with the structure of the heart. "Congenital" means that that the problems are present at birth. These defects happen when a fetus's heart doesn't develop normally during pregnancy.…
Your skin is your body's largest organ. It has many different functions, including covering and protecting your body. It helps keep germs out. But sometimes the germs can cause a skin infection. It often happens when the germs enter…
Blood glucose, or blood sugar, is the main sugar found in your blood. It is your body's primary source of energy. It comes from the food you eat. Your body breaks down most of that food into glucose and releases it into your…
Your liver is the largest organ inside your body. It helps you digest food, store energy, and remove harmful substances (toxins). Steatotic liver disease, formerly called fatty liver disease, happens when too much fat builds up in…
Sarcoidosis is a condition in which groups of cells in your immune system form small, red, and swollen (inflamed) lumps. These lumps are called granulomas. They can form in any organ in the body. But they most commonly affect the…
When your kidneys are healthy, they clean your blood. They also make hormones that keep your bones strong and your blood healthy. When your kidneys fail, you need treatment to replace the work your kidneys used to do. Unless you have…
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