Thrombotic thrombocytopenic purpura (TTP) is a serious disorder that involves the formation of small blood clots throughout the body that block the flow of blood to vital organs such as the brain, heart, and kidneys.
Symptoms are related to where in the body blood clots form.
Diagnosis is based on the person's symptoms and blood tests.
(See also Overview of Platelet Disorders and Overview of Thrombocytopenia.)
Thrombotic means that blood clots form, thrombocytopenic means the platelet count is low, and purpura means that purple spots or bruises appear on the skin. Thrombotic thrombocytopenic purpura (TTP) is a rare disorder in which many small blood clots (thrombi) form suddenly throughout the body. It is related to hemolytic-uremic syndrome (HUS), but it is more likely to occur in adults than HUS, which is more common in children.
The blood clots in TTP are not large clots that block large blood vessels, like in deep vein thrombosis. Instead, in TTP, there are many small clots that block small blood vessels throughout the body, particularly those in the brain, heart, and kidneys. The blood vessel blockage damages organs and can break apart red blood cells that pass through partially blocked vessels. The blood clots also use up an abnormally high number of platelets, which leads to a sharp decrease in the number of platelets in the bloodstream (termed thrombocytopenia).
Platelets are cells that are made in the bone marrow and circulate in the bloodstream and help blood clot. Platelets are sometimes called thrombocytes.
Symptoms of TTP
In thrombotic thrombocytopenic purpura (TTP), symptoms develop suddenly.
Symptoms in TTP are quite distinct from symptoms of most other forms of thrombocytopenia.
In TTP, the small blood clots that develop (using up platelets) cause a wide range of symptoms and complications, some of which can be life threatening. Symptoms that result from clots in the brain may include headache, confusion, seizures, and coma. Symptoms that result from clots in the brain may come and go and may vary in severity. Symptoms that result from clots elsewhere in the body include abnormal heart rhythms, blood in the urine, and abdominal pain.
Diagnosis of TTP
Tests to rule out other disorders that cause a low platelet count and bleeding
Doctors suspect thrombotic thrombocytopenic purpura (TTP) when they find a low platelet count in people who have been ill, who have taken certain drugs, or who are pregnant.
Treatment of TTP
Corticosteroids and plasma exchange
With thrombotic thrombocytopenic purpura (TTP), people are often treated with corticosteroids and plasma exchange (plasma transfusions along with plasmapheresis). In plasmapheresis, blood is taken from the person and put in a machine that separates the blood cells from the liquid part of the blood (plasma). The plasma, which contains disease-causing antibodies, is discarded and the blood cells are returned to the person along with fresh plasma obtained from health donors.
