Thrombotic thrombocytopenic purpura diagnosis

Suggested Alternatives for Differential Diagnosis Malaria, typhoid fever, shigellosis, meningococcemia, salmonella infection, other tick-borne diseases, rickettsial infections, leukemia, lupus, disseminated intravascular coagulation, hemolytic uremic syndrome, leptospirosis, thrombocytopenic purpura, and idiopathic or thrombotic thrombocytopenic purpura. 

Thrombotic thrombocytopenic purpura is a rare acute or subacute disease in adults, rather similar to the hemolytic uremic syndrome in children, in which there is systemic malaise, fever, skin purpura, renal failure, hematuria and proteinuria. Hemorrhagic infarcts caused by platelet microthrombi occur in many organs in the brain they may cause stroke-like episodes (Matijevic and Wu 2006) although more commonly there is global encephalopathy. The blood film shows thrombocytopenia, hemolytic anemia and fragmented red cells. The differential diagnosis includes infective endocarditis, idiopathic thrombocytopenia, heparin-induced thrombocytopenia with thrombosis, systemic lupus erythematosus, non-bacterial thrombotic endocarditis and disseminated intravascular coagulation. 

The differential diagnosis includes a number of viral and bacterial diseases, including influenza, meningo-coccemia. Rocky Mountain spotted fever, malaria, and others, as well as noninfectious causes such as idiopathic and thrombotic thrombocytopenic purpuras, hemolytic uremic syndrome, and DlC (disseminated intravascular coagulation). 

Thrombotic thrombocytopenic purpura has been repeatedly reported (6). The incidence has been estimated at 1 in 1600 (based on the observation of 5 cases out of a total of 7842 patients studied after coronary stent placements) (13). This rare adverse reaction is generally observed after a short exposure period of about 3-8 weeks. The clinical features are generally indistinguishable from those of idiopathic thrombotic thrombocytopenic purpura (14). The pathogenesis is unknown. Platelet antibodies were found in one patient, suggesting an immunologic mechanism (6). The outcome appears to be favorable in comparison to that of idiopathic thrombotic thrombocytopenic purpura, but several authors have reported cases in which death resulted (15,16). Early diagnosis and the rapid institution of plasmapheresis provide the best hope of complete recovery. 

The differential diagnosis in most areas of the world has malaria at the top of the list. However, the presence of parasitemia in patients partially immune to malaria does not prove that malaria is the cause of the symptoms (48). Other confounding infections include typhoid fever, rickettsial and leptospiral diseases, nontyphoidal salmonellosis, shigellosis, relapsing fever, fulminant hepatitis, and meningococ-cemia. In patients with DIG, the differential diagnosis includes acute leukemia, lupus erythematosus, idiopathic or thrombotic thrombocytopenic purpura and hemolytic uremic syndrome (48). 

Tsai HM (2003) Advances in the pathogenesis, diagnosis, and treatment of thrombotic thrombocytopenic purpura. J Am Soc Nephrol, 14 1072-1081. 

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