Histopathologic Characteristics of Hemolytic Uremic Syndrome in Children and their Correlation with early Outcome

Hemolytic uremic syndrome(HUS) is the most common cause of renal failure in children. Hemolytic microangiopathic anemia, thrombocytopenia and renal failure are diagnostic triads of the disease. The aim of the preset study is determining histopathological findings of renal biopsy and their correlation with early outcome of the patients. Patients and In this cross-sectional retrospective study a total number of 28(20 males & 8 females) cases of HUS with mean age of 6 years(± 4.6) who were admitted in Ali-Asghar children hospital from 1994 to 2004 were evaluated. Light microscopic findings of glomeruli(sclerosis, necrosis, capillary loop thickening, crescent, …), arterioles (hyperplastic thickening, thrombi, necrosis, …), arterial(thrombi, necrosis, intimal lipid, …) interstitial(inflammation, fibrosis, edema), medullary vessels and tubules were scored without knowledge of clinical history. Short outcome was defined as appearing of initial improvement signs in less than 3 weeks. The data were analyzed via SPSS V.11.5 software statistical tests such as Pearson correlation and Linear regression. The most common lesions in glomeruli were capillary wall thickening and reduction in luminal size. In arterioles mild luminal stenosis, in arteries intimal thickening, in interstitium mild chronic inflammatory cell infiltration and interstitial edema, in vasa recta congestion and in tubules presence of casts were the most common findings. Arteriolar lesion(arteriolothrombosis) had significant correlation with the serum creatinin level at time of discharge. Vascular lesions(especially arteriolar) are the most important predictors of short outcome of children with HUS.