Acrorenal syndrome is a rare genetic disorder that affects the development of the kidneys and the extremities. It is characterized by the presence of abnormal kidneys, short stature, and malformations of the hands and feet. It is caused by a mutat...

ACTH deficiency is a rare disorder caused by a lack of the hormone adrenocorticotropic hormone (ACTH). This hormone is produced by the pituitary gland and is responsible for stimulating the adrenal glands to produce cortisol, a hormone that helps ...

An actinic keratosis (ak-TIN-ik ker-uh-TOE-sis) is a rough, scaly patch on your skin that develops from years of exposure to the sun. It's most commonly found on your face, lips, ears, back of your hands, forearms, scalp or neck. Also know...

Actinic lichen planus is a type of lichen planus that is caused by long-term exposure to ultraviolet (UV) radiation from the sun. It is characterized by flat-topped, scaly, and itchy patches on the skin that are usually found on sun-exposed areas ...

Actinic prurigo is a rare skin condition that is caused by an abnormal reaction to sunlight. It is characterized by itchy, red bumps that appear on areas of the skin that are exposed to the sun. The bumps can become scaly and may even blister. Tre...

Actinomycosis is a rare bacterial infection caused by the Actinomyces bacteria. It usually affects the face, neck, and chest, but can spread to other parts of the body. Symptoms may include fever, fatigue, and a lump or abscess in the affected are...

Action myoclonus-renal failure syndrome (AMRF) is a rare genetic disorder characterized by myoclonus (involuntary muscle jerks) and progressive renal failure. It is caused by mutations in the gene SLC33A1, which is responsible for the production o...

Activated PI3K-delta syndrome (APDS) is a rare genetic disorder caused by mutations in the PIK3CD gene. It is characterized by recurrent infections, enlarged lymph nodes, and an increased risk of developing certain types of cancer. Other symptoms ...

Acute ackee fruit intoxication is a type of food poisoning caused by eating unripe ackee fruit. The unripe fruit contains a toxin called hypoglycin A, which can cause severe vomiting, hypoglycemia, and even death if left untreated. Symptoms usuall...

Acute annular outer retinopathy (AOOR) is a rare eye disorder that affects the peripheral retina. It is characterized by the sudden onset of a ring-shaped lesion in the outer retina, which can cause vision loss. The cause of AOOR is unknown, but i...

Acute basophilic leukemia (ABL) is a rare type of acute myeloid leukemia (AML) that is characterized by an abnormal increase in the number of basophils, a type of white blood cell. It is a very aggressive form of leukemia and is often difficult to...

Acute bilirubin encephalopathy is a neurological disorder caused by high levels of bilirubin in the blood. It is most commonly seen in newborns, and is caused by an inability of the liver to process bilirubin. Symptoms of acute bilirubin encephalo...

Acute cholecystitis is an inflammation of the gallbladder, usually caused by a gallstone blocking the cystic duct. Symptoms may include abdominal pain, nausea, vomiting, and fever. Treatment typically involves antibiotics and surgery to remove the...

Acute Disseminated Encephalomyelitis (ADEM) is an inflammatory disorder of the central nervous system (CNS) that is characterized by a sudden onset of neurological symptoms. It is thought to be an autoimmune disorder, in which the body's own immun...

Acute disseminated encephalomyelitis with anti-MOG antibodies (ADEM-MOG) is a rare autoimmune disorder of the central nervous system (CNS) characterized by inflammation of the brain and spinal cord. It is caused by the body's immune system attacki...

Acute disseminated encephalomyelitis (ADEM) without anti-MOG antibodies is an inflammatory demyelinating disorder of the central nervous system (CNS) that is characterized by a sudden onset of neurological symptoms, including fever, headache, conf...

Acute encephalopathy with biphasic seizures and late reduced diffusion (AESD) is a rare neurological disorder characterized by recurrent seizures, encephalopathy (brain dysfunction), and reduced diffusion of water molecules in the brain on MRI sca...