Thrombotic thrombocytopenic purpura
Thrombotic thrombocytopenic purpura (TTP) is a blood disorder that causes blood clots to form in small blood vessels around the body. This leads to a low platelet count (thrombocytopenia
This disease may be caused by problems with ann enzyme (a type of protein) that is involved in blood clotting. These changes cause clotting to occur in an abnormal way.
- As the platelets clump together in these clots, fewer platelets are available in the blood in other parts of the body to help with clotting.
- This can lead to bleeding under the skin and purple-colored spots called purpura.
- The blood clots prevent oxygen from reaching these parts of the body.
In some cases, the disorder is passed down through families (inherited). In these cases, people are born with naturally low levels of this enzyme. This condition also may be related to:
- Hematopoietic stem cell transplantation
- HIV infection
- Hormone replacement therapy and estrogens
- Medications (including ticlopidine, clopidogrel, guinine, and cyclosporine A)
Plasma exchange (plasmapheresis plus infusion of donor plasma) is used to remove the antibodies that are affecting clotting from the blood. It also replace the missing enzyme.
First, you will have your blood drawn as if you were donating blood.
The plasma portion of the blood will be passed through a cell separator. The remaining portion of the blood will be saved.
Plasma will be added to it, and the blood will be returned to you through a transfusion.
This treatment is repeated daily until blood tests show improvement.
People who do not respond to this treatment or whose condition often returns may need to:
Have surgery to remove their spleen
Get drugs that suppress the immune system, such as corticosteroids or rituximab
Plasma exchange has greatly improved the outcome of this disease. Most people can recover completely. However, some people die from this disease, especially if it is not diagnosed immediately. In people who don't recover, this condition can become long-term (chronic).
- Kidney failure
- Low platelet count (thrombocytopenia)
- Low red blood cell count (caused by the premature breakdown of red blood cells)
- Nervous system problems
- Severe bleeding (hemorrhage)
When to Contact a Medical Professional
Call your health care provider if you have any unexplained bleeding.
Because the cause is unknown, there is no known way to prevent this condition.
McCrae KR, Sadler JE, Cines DB. Thrombotic thrombocytopenic purpura and the hemolytic uremic syndrome. In: Hoffman R, Benz EJ Jr, Silberstein LE, Heslop HE, Weitz JI, eds. Hematology: Basic Principles and Practice. 6th ed. Philadelphia, PA: Saunders Elsevier; 2012:chap 136.
Abrams CS. Thrombocyopenia. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine. 24th ed. Philadelphia, PA: Saunders Elsevier; 2011:chap 179.
Yi-Bin Chen, MD, Leukemia/Bone Marrow Transplant Program, Massachusetts General Hospital. Also reviewed by A.D.A.M. Health Solutions, Ebix, Inc., Editorial Team: David Zieve, MD, MHA, Bethanne Black, Stephanie Slon, and Nissi Wang.