Thrombotic thrombocytopenic purpura (TTP) and hemolytic uremic syndrome (HUS) are classical diseases characterized by thrombocytopenia and microangiopathic hemolytic anemia. Microangiopathic hemolytic anemia is also a part of clinical picture in patients with hemorrhagic fever with renal syndrome (HFRS). Some overlap in other elements of clinical picture between TTP and HFRS is possible, which could pose difficulties in differential diagnosis. Early treatment of patients with TTP is essential and significantly improves the outcome, whereas the treatment of HFRS is mainly supportive. In the last ten years, we treated 13 patients with TTP and 17 patients with HFRS. Two patients with HFRS were initially treated as TTP because it was not possible to exclude TTP on the basis of clinical picture. Further clinical course and serologic tests excluded TTP and suggested HFRS.

CONCLUSIONS

Sometimes it is difficult to distinguish HFRS from TTP because thrombocytopenia and microangiopathic hemolytic anemia are present in both diseases and overlaps in other parts of clinical picture are possible. The serious consequences of delay in the efficacious treatment of patients with TTP could also influence the physicians' decisions.