[Hemolytic uremic syndrome]

The glomerular lesions in endotheliotropic hemolytic nephroangiopathy (hemolytic uremic syndrome, malignant nephrosclerosis, post partum renal insufficiency)

The term "Endotheliotropic Hemolytic Nephroangiopathy" (EHN) comprises various clinically or pathomorphologically defined disease states with severe renal lesions (e.g. hemolytic uremic syndrome, malignant nephrosclerosis, post partum renal insufficiency) which, to date, have been considered as different entities. We attempted to assign accompanying glomerular changes based upon light and electron microscopy to the above mentioned clinical pictures and their various stages. The accordingly classified glomerular lesions (G1--G3 and Ga) are of critical importance in pathohistological differential diagnosis. Since it is assumed that fibrin is a causing event in the pathogenesis of the vascular lesions, quantitative evaluation of glomerular fibrin deposits was done. The results, when viewed with respect to time, lead to the conclusion that the microthrombotic component represents a secondary phenomenon. Thus, the primary and hence pathogenetically most important finding is a severe damage to the endothelium of the terminal renal vasculature. This endothelial damage although being expressed with variable intensity has to be regarded as the common denominator inherent to all types of glomerular lesions in EHN.