A severe multisystem disorder with an array of fever, thrombocytopenia,microangiopathic hemolytic anemia, neurologic and renal involvement. There is thrombosis of capillaries and arterioles without much inflammation. The thrombus is primarily platelets-fibrin. It is floridly disseminated into almost all organs including pancreas, adrenals, heart, brain and kidney. Its slightly more common in women and peaks in third to fourth decades. Mortality is much lower with plasma exchange, but about 40 % of survivors will relapse.
Triggers include no identifiable cause in 90 %, but the others include infection, CT disease, immune complex disease, drug reaction, neoplasia, pregnancy, penicillamine, penicillin, HIV and postpartum state.
Onset is usually subacute with headache, confusion, disorientation, and fluctuating neurological signs. Also, patients get hemorrhagic cutaneous lesions (purpura, petecchiae, ecchymosis) andominal pain, arthralgia and myalgia. Rarely it causes sudden death due to involvement of cardiac conduction system. Most common neurologic symptoms are confusion (80%), headache (30%), pareses (30%), transient aphasia (30%), seizures (20%), and coma (10%).
The hemolytic anemia is Coombs negative, with fragmented and misshapen blood cells, with severe thrombocytopenia around 20K or so. PT, PTT, fibrinogen, FDP are usually normal or nearly so. Biopsy of gingiva, bone marrow, spleen, and skin show characteristic microvascular hyaline thrombi about one third to half the time. CT may or may not be normal. MRI shows deep punctate lesions. After an average of nine exchanges, platelet count will be normal although improvement will be seen sooner. Other treatments are IVIG, vincristine, iv prostacyclin, splenectomy. In relapses, repeat exchange is used and splenectomy can induce long term stabilization. Don't transfuse platelets. +/- steroids, antiplatelet agents
Associations: thienopyridines esp ticlopidine
Triggers include no identifiable cause in 90 %, but the others include infection, CT disease, immune complex disease, drug reaction, neoplasia, pregnancy, penicillamine, penicillin, HIV and postpartum state.
Onset is usually subacute with headache, confusion, disorientation, and fluctuating neurological signs. Also, patients get hemorrhagic cutaneous lesions (purpura, petecchiae, ecchymosis) andominal pain, arthralgia and myalgia. Rarely it causes sudden death due to involvement of cardiac conduction system. Most common neurologic symptoms are confusion (80%), headache (30%), pareses (30%), transient aphasia (30%), seizures (20%), and coma (10%).
The hemolytic anemia is Coombs negative, with fragmented and misshapen blood cells, with severe thrombocytopenia around 20K or so. PT, PTT, fibrinogen, FDP are usually normal or nearly so. Biopsy of gingiva, bone marrow, spleen, and skin show characteristic microvascular hyaline thrombi about one third to half the time. CT may or may not be normal. MRI shows deep punctate lesions. After an average of nine exchanges, platelet count will be normal although improvement will be seen sooner. Other treatments are IVIG, vincristine, iv prostacyclin, splenectomy. In relapses, repeat exchange is used and splenectomy can induce long term stabilization. Don't transfuse platelets. +/- steroids, antiplatelet agents
Associations: thienopyridines esp ticlopidine
No comments:
Post a Comment