Diseases Studied
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All Diseases > Immune thrombotic thrombocytopenia
Immune thrombotic thrombocytopenia
Alternative Names: iTTP
Disease Category: Thrombotic Microangiopathies
Thrombotic thrombocytopenic purpura (TTP), acquired is a blood disorder characterized by low platelets (i.e., thrombocytopenia), small areas of bleeding under the skin (i.e., purpura), low red blood cell count, and hemolytic anemia. TTP causes blood clots (thrombi) to form in small blood vessels throughout the body. These clots can cause medical problems if they block vessels and decrease or stop blood flow to organs such as the brain, kidneys, and heart. Complications may include neurological problems (such as headaches, confusion, slurred speech, and coma), fever, abnormal kidney function, abdominal pain, and heart problems. Hemolytic anemia can lead to fatigue, paleness, yellowing of the eyes and skin (jaundice), fatigue, shortness of breath, and a rapid heart rate. Acquired TTP usually begins in adulthood but can also affect children. An episode of TTP usually occurs suddenly and lasts for days or weeks, but it may continue for months. Acute episodes of TTP are life threatening, and untreated TTP is fatal in 90%. Relapses (or flareups) can occur in up to 60 percent of people who have the acquired TTP. Acquired TTP is caused when a person's body mistakenly makes antibodies that block the activity of the ADAMTS13 enzyme. The ADAMTS13 enzyme normally helps control the activity of a blood clotting factor called von Willebrand factor.