TTP is 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.
Signs and tests
Platelet count , decreased CBC showing anemia
Bilirubin , elevated Peripheralblood smear showing schistocytes and fragmented blood cells Urinalysis showing protein or microscopic blood
Elevated creatinine level
Mucus membrane biopsy revealing platelet thrombi in small blood vessels
Treatment
Plasmapheresis, or plasma exchange, is used to remove unwanted substances from the blood ( antigen antibody complexes), and to replace the missing protease. Blood is withdrawn from the patient as for a blood donation. Then the plasma portion of the blood is passed through a cell separator. The remaining portion of the blood is saved, reconstituted with fresh plasma, and returned to the patient as a blood transfusion. In thrombotic thrombocytopenic purpura, this treatment is repeated daily until blood tests show improvement. People who do not respond to this treatment, or have frequent recurrences, may require the removal of the spleen.
Expectations (prognosis)
Plasmapheresis has improved the outcome of this disease so that 80 to 90% of patients now recover completely. However, fatalities still occur. With relapses, the remaining cases become chronic .
Prevention
Because the specific cause is unknown, specific prevention is also unknown.