Collagen type III glomerulopathy: A case report and review of 20 cases

Collagen type III glomerulopathy is a non-immune-mediated glomerular disease, characterized by abnormal accumulation of type III collagen fibrils within the mesangial matrix and subendothelial space. The clinical manifestations of this disease are proteinuria, peripheral edema, hypertension and occasional progression to end-stage renal disease. Collagen type III glomerulopathy is extremely rare, and its etiology and pathogenesis remain elusive. To date, only case reports are available and the majority of these are from Japan. To investigate the idiographic features of collagen type III glomerulopathy in China, we report a case of collagen type III glomerulopathy with two differing renal biopsies and review 20 cases in China. The majority of the Chinese patients were adults. Thirty percent of the patients had nephrotic syndrome, and hypertension was observed in 75% of cases. Elevated creatinine was present in 45% of patients. The pathology of collagen type III glomerulopathy in the Chinese cases was similar to that observed in other ethnicities, although certain cases were IgA-positive by immunofluorescence microscopy, and electron-dense material could be observed in the mesangial area. The onset age, clinical manifestations and pathological features of the disease are not exactly the same in China as worldwide.