DE-NOVO COLLAPSING GLOMERULOPATHY IN RENAL-ALLOGRAFTS

Background. Collapsing glomerulopathy is a recently described form of glomerular injury characterized by capillary collapse and visceral epi thelial hypercellularity associated with nephrotic range proteinuria a nd a rapid, progressive decline in renal function. The lesion has rare ly been described in allografts,Methods. We reviewed 892 allograft bio psies from a population of 1079 recipients who received renal transpla nts between 1978 and 1996, Results, Five cases of de novo collapsing g lomerulopathy were identified (0.6% of biopsies; 3.2% since 1993), Non e occurred before 1993, The patients were 31 to 66 years of age and th ey presented 6 to 25 months after transplantation, The 24-hr urinary p rotein ranged from 1.8 to 11.8 g, All patients and donors were negativ e for the human immunodeficiency virus and had no risk factors for hum an immunodeficiency virus infection. Diffuse or focal, global or segme ntal collapse of glomerular capillaries, swelling and hypercellularity of the visceral epithelium, hyaline arteriolosclerosis, and interstit ial fibrosis were characteristic histologic features. Two cases had co ncomitant glomerular immune complex deposits. Progressive decline in a llograft function occurred within 2-24 months after diagnosis, culmina ting in return to dialysis in all patients. Conclusion. Collapsing glo merulopathy can arise in renal allografts as a de novo disease. Althou gh its pathogenesis remains to be clarified, it is important to distin guish this lesion in allografts as it can be associated with rapidly p rogressive graft failure.