Aicardis syndrome A rare genetic disorder that occurs only in females and is caused by congenital absence of the corpus callosum, a large bundle of nerves that connects the left and right sides of the brain. Features include epilepsy that emerges in infancy and is difficult to control, vision problems due to maldeveloped retinas, developmental…
AID Artificial insemination by donor.
AIDS Acquired immunodeficiency syndrome, a syndrome caused by infection with the human immunodeficiency virus (HIV), with ensuing compromise of the body’s immune system. Features include deficiency of certain types of leukocytes, especially T cells; infection with opportunistic infections that take advantage of the impaired immune response, such as tuberculosis, bacterial pneumonia, human herpes virus, or…
AIDS dementia complex A brain disorder in people with severe AIDS, causing loss of thinking capacity and affecting the ability to function. AIDS dementia complex is considered an AIDS-defining illness—that is, one of the serious illnesses that occurs in HIV-positive individuals warranting an AIDS diagnosis, according to the definition of AIDS by the Centers for…
AIDS-related complex A term used in the early years of the AIDS epidemic to describe people with HIV infection who had only mild symptoms of illness, such as swollen lymph glands. It is rarely used today. Abbreviated ARC.
airway The path that air follows to get into and out of the lungs. The mouth and nose are the normal entry and exit ports for the airway. Entering air then passes through the back of the throat (pharynx) and continues through the voice box (larynx), down the trachea, to finally pass through the bronchi.
airway obstruction Partial or complete blockage of the breathing passages to the lungs. Causes include the presence of foreign matter, allergic reactions, infections, anatomical abnormalities, and trauma. Associated respiratory distress may be sudden, with only a cough for a warning. There is often agitation in the early stages. Other signs include labored, ineffective breathing, until…
AKA Above-the-knee amputation, generally performed when the leg is not medically viable or to prevent the spread of disease to the tissues above the knee from below.
akathisia A movement disorder characterized by a feeling of inner restlessness and a compelling need to be in constant motion, as well as by actions such as rocking while standing or sitting, lifting the feet as if marching on the spot, and crossing and uncrossing the legs while sitting. People with akathisia are unable to…
akinesia The state of being without movement.
akinetic Related to the loss of the normal ability to move the muscles.
alanine aminotransferase An enzyme normally present in liver, skeletal muscle, and heart cells. Abbreviated ALT. ALT is released into blood when the liver, skeletal muscle, or heart is inflamed or injured by diseases, conditions, or medications. Also known as serum glutamic pyruvic transaminase (SGPT).