Dictionary

hereditary spherocytosis See spherocytosis, hereditary.

hereditary mutation A gene change that occurs in a germ cell (an egg or a sperm) and is then incorporated into every cell in the developing body of the new organism. Hereditary mutations play a role in cancer, as, for example, in the eye tumor retinoblastoma and Wilms’ tumor of the kidney. Also known as…

hereditary multiple exostoses See osteochondromatosis.

hereditary hemorrhagic telangiectasia A genetic disease characterized by the presence of multiple direct connections between arteries and veins called arteriovenous malformations (AVMs). Small AVMs, or telangiectases, close to the surface of skin and mucous membranes often rupture and bleed after slight trauma. Abbreviated HHT. The most common manifestations of HHT are recurrent nosebleeds beginning at…

hereditary angioneurotic edema See angioedema, hereditary.

Herceptin Brand name of the drug trastuzumab, a type of targeted cancer therapy known as a monoclonal antibody, for women with breast cancer whose tumors produce too much HER2 protein. This type of cancer is known as “HER2-positive.” See also HER2.

herbalist One versed in herbal lore and, in regard to therapy, an herb physician. Herbalists may be licensed MDs, naturopaths, or osteopaths. They may also be unlicensed. People who are interested in herbalism should seek out knowledgeable, and preferably licensed, herbalists. See also herbalism.

herbalism The practice of making or prescribing herbal remedies for medical conditions. Practitioners of herbalism may be licensed or unlicensed. See also herbalist.

herbal remedy A medication prepared from plants, including most of the world’s traditional remedies for disease. Most people think of herbal remedies as products sold over the counter as “supplements,” such as saw palmetto extract and goldenseal ointment. However, many over-the-counter and prescription drugs, including aspirin and digoxin, are based on ingredients originally derived from…

HER2 1 Human epidermal growth factor receptor. 2 A protein involved in normal cell growth that is found in abnormally high levels on, and promotes the growth of, some cancer cells, notably breast cancer cells. HER2-positive breast cancers tend to be more aggressive than other types of breast cancer and are less responsive to treatment…

hepatotoxic Being injurious to the liver. For example, alcoholic beverages and acetaminophen (brand name: Tylenol) can be hepatotoxic.

hepatosplenomegaly Abnormal enlargement of the liver and spleen. Hepatosplenomegaly is typically associated with chronic liver diseases.