Thrombotic thrombocytopenic purpura

Alternative names:

Moschcowitz's disease; TTP

Definition:

A disorder of the blood characterized by low platelets, low red blood cell count (caused by premature breakdown of the cells), and neurological abnormalities.

Causes, incidence, and risk factors:

This disease is seen most commonly in adults from 20 to 50 years old, with women affected slightly more often than men. Purpura refers to the characteristic bleeding that occurs beneath the skin, or in mucus membranes, which produces bruises, or a red rash-like appearance. A similar condition in children is hemolytic-uremic syndrome.

The disease may be precipitated by the use of estrogen or by pregnancy. It is frequently preceded by a viral infection. It is also associated with HIV infection. The neurological symptoms associated with this disease may vary over several minutes and include headaches, confusion, speech changes, and alterations in consciousness, which vary from lethargy to coma. People may be very ill with this disorder, and kidney abnormalities may develop. The cause of the disease is unknown, but it is thought to be caused by the development of antibodies. Risk factors are being between 20 and 50 years old, recent estrogen use or pregnancy, and HIV infection. The incidence is 4 out of 100,000 people.