Key Points

• Thrombotic thrombocytopenic purpura (TTP) is a rare blood condition. It causes blood clots to form in small blood vessels throughout the body. These blood clots can cause serious problems if they block blood vessels and limit blood flow to the brain, kidneys, or heart.
• Blood clots form when blood cells called platelets clump together. When this happens, there are fewer platelets in the blood. This can cause bleeding into the skin (purpura), prolonged bleeding from cuts, and internal bleeding.
• TTP also can cause red blood cells to break apart faster than the body can replace them. This leads to hemolytic anemia.
• TTP has two main types: inherited and acquired. Inherited TTP mainly affects newborns and children. Acquired TTP occurs mostly in adults, but sometimes affects children.
• A lack of activity in the ADAMTS13 enzyme (a type of protein in the blood) causes TTP. The ADAMTS13 gene controls the enzyme, which is involved in blood clotting. Not having enough enzyme activity causes platelets to clump together, forming blood clots.
• What triggers inherited and acquired TTP isn’t known, but some diseases or conditions, medical procedures, and medicines may contribute to it.
• About 1,200 new cases of TTP occur each year in the United States. Most cases of TTP are the acquired type. The condition is seen more often in women than in men.
• Signs and symptoms of TTP include purplish spots called purpura on the skin or mucous membranes, paleness or jaundice (a yellowish color of the skin or eyes), fatigue (tiredness) and weakness, fever, a fast heart rate or feeling short of breath, headache, speech changes, confusion, coma, stroke, seizure, a low amount of urine, or protein or blood in the urine. If you have any of these signs and symptoms, call your doctor right away.
• A diagnosis of TTP is based on your medical history, a physical exam, and test results.
• TTP is usually treated with infusions of fresh frozen plasma or plasma exchange. Other treatments, such as medicines and surgery, are used when plasma treatment doesn’t work well or relapses (flareups) occur often.
• Both inherited and acquired TTP appear suddenly with no clear cause. You can’t prevent either type.
• You should call your doctor right away if you have signs or symptoms of a TTP flareup. These are the same as the initial signs and symptoms of TTP.
• You also should report any symptoms of infection. Talk to your doctor about changing medicines that may raise your risk for TTP or bleeding.
• Most people recover fully from TTP when treated promptly. Flareups can occur in 30 to 60 percent of people with acquired TTP. They also occur in most people with inherited TTP.