Two cases of Type III collagen glomerulopathy and literature review.

In this paper, 2 cases of collagen Type Ⅲ glomerulopathy were analyzed. The clinical manifestations mainly included nephrotic syndrome, proteinuria, hypertension and renal dysfunction. One patient showed that the complement factor H-related protein 5 (CFHR5) gene was likely a disease-causing mutation. The pathological examination of renal tissues showed hyperplasia of mesangial matrix, sub-endothelial insertion, and double-track formation. Immunohistochemistry of Type III collagen was positive. Electron microscopy revealed that massive collagen fibers (40-70 nm in diameter) deposited in the mesangial matrix and basement membrane. As for the follow-up results, the normal renal function had kept steady and the proteinuria was moderate in 1 case treated with angiotensin Ⅱ receptor blocker. Due to other system disease, another case developed into acute kidney injury and then received hemodialysis. The clinical manifestations of collagen Type Ⅲ glomerulopathy was atypical, the light microscope pathological features were various, and the disease was mainly diagnosed by electron microscopy and immunohistochemistry.