An anal fistula is a small tunnel that develops between the end of the bowel and the skin near the anus. It is usually the result of an infection in the area around the anus, such as an abscess. Anal fistulas can cause pain, discharge, and other s...

When a person suffers from allergies, certain allergens can trigger a reaction and cause swe...

Anaplastic astrocytoma is a type of brain tumor that is classified as a grade III astrocytoma. It is a malignant tumor that is composed of cells that resemble astrocytes, a type of glial cell found in the brain. It is typically found in the cerebr...

Anaplastic ependymoma is a rare type of brain tumor that develops from cells that line the ventricles of the brain. It is a malignant tumor that can spread to other parts of the brain and spinal cord. Symptoms of anaplastic ependymoma can include ...

Anaplastic ganglioglioma is a rare type of brain tumor that is composed of both glial cells (astrocytes and oligodendrocytes) and neurons. It is usually found in the cerebral hemispheres of the brain, and is most commonly seen in children and youn...

Anaplastic large cell lymphoma (ALCL) is a type of non-Hodgkin lymphoma, a cancer of the lymphatic system. ALCL is a rare type of lymphoma that usually affects the skin, lymph nodes, and other organs. It is characterized by the presence of large, ...

Anaplastic oligoastrocytoma is a type of brain tumor that is classified as a grade III astrocytoma. It is a rare type of tumor that is composed of both oligodendrocyte and astrocyte cells. It is usually found in the cerebral hemispheres of the bra...

Anaplastic oligodendroglioma is a type of brain tumor that is composed of cells called oligodendrocytes. It is a rare type of cancer that usually occurs in the brain, but can also occur in the spinal cord. It is usually found in adults, but can al...

Anaplastic thyroid carcinoma (ATC) is a rare and aggressive form of thyroid cancer. It is characterized by the rapid growth of cancer cells that invade surrounding tissues and spread to other parts of the body. ATC is the most advanced form of thy...

Anaplastic/large cell medulloblastoma is a rare and aggressive type of brain tumor that affects the cerebellum, which is the part of the brain responsible for controlling movement and coordination. It is a malignant tumor that is composed of large...

Anauxetic dysplasia is a rare genetic disorder characterized by abnormal growth of the bones and joints. It is caused by mutations in the gene encoding the protein F-box and WD repeat domain containing 7 (FBXW7). Symptoms of anauxetic dysplasia in...

Andersen Disease (GSD IV) is a rare inherited disorder that affects the body's ability to break down certain carbohydrates. It is caused by a deficiency of the enzyme alpha-1,4-glucosidase, which is responsible for breaking down glycogen, a type o...

Andersen-Tawil Syndrome (ATS) is a rare genetic disorder characterized by a combination of physical, neurological, and cardiac abnormalities. It is caused by mutations in the KCNJ2 gene, which is responsible for the production of the potassium cha...

ANE syndrome (also known as Aicardi-Goutières Syndrome) is a rare genetic disorder that affects the brain and immune system. It is characterized by neurological problems, such as seizures, developmental delays, and intellectual disability, as wel...

What is sickle cell anemia? Sickle cell anemia (sickle cell disease) is a disorder of the blood caused by an inherited abnormal hemoglobin (the oxygen-carrying protein within the red blood cells). The abnormal hemoglobin causes distorted (...

What is sickle cell anemia? Sickle cell anemia (sickle cell disease) is a disorder of the blood caused by an inherited abnormal hemoglobin (the oxygen-carrying protein within the red blood cells). The abnormal hemoglobin causes distorted (...

Anemia of chronic disease (ACD) is a type of anemia that occurs when the body's inflammatory response to a chronic illness or infection interferes with the production of red blood cells. It is a common complication of many chronic diseases, includ...