Attention deficit hyperactivity disorder (ADHD) is one of the most common chronic disorders affecting school-age children. Current research indicates prevalence rates of 3% to 5% with males being diagnosed with this disorder two and a half times m...

Attenuated Chediak-Higashi syndrome (A-CHS) is a rare, inherited disorder that affects the immune system. It is caused by a mutation in the CHS1 gene, which is responsible for producing a protein that helps the body fight off infections. People wi...

ATTRV122I amyloidosis is a rare, inherited form of amyloidosis caused by a mutation in the transthyretin (TTR) gene. It is characterized by the buildup of abnormal proteins in the body's organs and tissues, leading to organ damage and other seriou...

ATTRV30M amyloidosis is a rare, progressive, and fatal genetic disorder caused by a mutation in the transthyretin (TTR) gene. It is characterized by the buildup of abnormal proteins called amyloid in the body's organs and tissues, which can lead t...

Atypical autism is a form of autism that is characterized by milder symptoms than those seen in other forms of autism. People with atypical autism may have difficulty with social interaction, communication, and repetitive behaviors, but these diff...

Atypical chronic myeloid leukemia (aCML) is a rare form of chronic myeloid leukemia (CML) that is characterized by an abnormal number of white blood cells, an abnormal number of immature cells, and an abnormal number of blasts in the bone marrow. ...

Atypical coarctation of the aorta is a rare congenital heart defect in which the aorta is narrowed in an abnormal location. It is usually located in the descending aorta, just beyond the left subclavian artery. This condition can cause a decrease ...

Atypical dentin dysplasia due to SMOC2 deficiency is a rare genetic disorder that affects the development of teeth. It is caused by mutations in the SMOC2 gene, which is responsible for producing a protein that is essential for the formation of de...

Atypical Fanconi syndrome-neonatal hyperinsulinism syndrome is a rare genetic disorder that affects the body’s ability to regulate insulin levels. It is characterized by an abnormally high level of insulin in the blood, which can lead to a varie...

Atypical Gaucher disease due to saposin C deficiency is a rare, inherited disorder caused by a mutation in the GBA gene. This mutation results in a deficiency of the enzyme saposin C, which is responsible for breaking down certain fats in the body...

Atypical glycine encephalopathy is a rare genetic disorder that affects the brain. It is caused by a mutation in the GLDC gene, which is responsible for producing an enzyme called glycine decarboxylase. This enzyme is necessary for the metabolism ...

Atypical Hemolytic Uremic Syndrome (aHUS) is a rare, life-threatening disorder that affects the kidneys, blood, and other organs. It is caused by abnormal activity of the complement system, a part of the immune system. Symptoms of aHUS include ane...

Atypical hemolytic uremic syndrome with anti-factor H antibodies (aHUS-AFH) is a rare, life-threatening disorder caused by an abnormal immune response. It is characterized by the formation of antibodies against the protein factor H, which is invol...

Atypical hypotonia-cystinuria syndrome is a rare genetic disorder characterized by hypotonia (low muscle tone), cystinuria (an inherited disorder of amino acid metabolism), and other symptoms. Symptoms may include delayed development, intellectual...

Atypical juvenile parkinsonism is a rare neurological disorder that affects children and young adults. It is characterized by symptoms similar to those of Parkinson's disease, including tremors, slow movement, and difficulty with balance and coord...

Atypical lichen myxedematosus is a rare autoimmune disorder that affects the skin. It is characterized by the formation of thick, waxy patches on the skin, usually on the face, neck, and upper chest. These patches can be itchy and may cause pain o...

Atypical Meigs syndrome is a rare condition characterized by the presence of a benign ovarian tumor (fibroma) and ascites (fluid accumulation in the abdomen). It is usually associated with pleural effusions (fluid accumulation in the chest cavity)...