Text Box: D-DIMER RISE IN THE COURSE OF HENOCH SCHONLEIN PURPURA (HSP) Zajadacz B, Juszkiewicz A Department of Pediatrics , District Hospital , Gorzow Wlkp., Poland Increased concentration of D-dimer, highly specific fibrin degradation fragment, indicate intensified plasmin degradation of fibrin and increased thrombin activity and fibrin formation. Detection of elevated plasma D-dimer level is strong evidence for the diagnosis of intravascular clotting process. According to most authors HSP is not accompanied by coagulation disturbances. In some reports, however, attention is focused on thrombocytopenia, lowered plasma levels of factor XIII as well as increased levels of the von Willebrandt factor and glomerular fibrin deposits. In available literature we have come across no descriptions of increased plasmatic levels of D dimer in the course of HSP, which we have observed in three successive cases. Upon admission to hospital, coagulative examinations were performed which revealed high level of D dimer and slightly extended kaolin-kephalin time. In one case of acute course HSP we observed beneficial influence of plasma and nadroparin treatment on course of disease . In two cases plasma D dimer increase did not correlate with severity of disease. It should be taken into consideration possibility of coagulation disturbances in HSP with D dimer rise (as well as decrease of plasma factor XIII and platelets described in relevant literature) . These results suggest presence of mild intravascular clotting process in course of disease. However, we were not able to clarify the pathogenesis of the high D dimer serum concentration in HSP. Thus, it is suggested that further research on the discussed condition should be conducted. 1899