Frey syndrome is a rare disorder that most often occurs as a result of surgery in the area near the parotid glands. The parotid glands are the largest salivary glands in the body located just below the ears on either side of the face. The main sym...

Frey syndrome is a rare disorder that most often occurs as a result of surgery in the area near the parotid glands. The parotid glands are the largest salivary glands in the body located just below the ears on either side of the face. The main sym...

Carcinoid syndrome is a disease consisting of a combination of symptoms, physical manifestations, and abnormal laboratory findings. Carcinoid syndrome is seen in individuals who have an underlying carcinoid tumour with spread to the liver. Carcino...

Paroxysmal cold hemoglobinuria (PCH) is a rare type of anemia characterized by the premature destruction of healthy red blood cells by autoantibodies. The disorder is classified as an autoimmune hemolytic anemia (AIHA), an uncommon group of disord...

Urticaria pigmentosa is a rare skin disorder that is a localized (cutaneous) form of mastocytosis. Some clinicians suggest that urticaria pigmentosa is the childhood form of mastocytosis. Mast cells are specialized cells of connective tissue that ...

Malignant carcinoid syndrome is characterized by a variety of signs and symptoms. Carcinoid tumors are neuroendocrine tumors that develop from primitive stem cells that can give rise to a variety of cell types. When a rare malignant...

Rosacea (roe-ZAY-she-uh) is a common skin condition that causes redness and visible blood vessels in your face. It may also produce small, red, pus-filled bumps. These signs and symptoms may flare up for a period of weeks to months and then dimini...

Systemic mastocytosis (mas-to-sy-TOE-sis) is a disorder that results in an excessive number of mast cells in your body. Mast cells normally help protect you from disease and aid in wound healing by releasing substances such as histamine and leukot...