COLLAGENOFIBROTIC GLOMERULONEPHROPATHY ASSOCIATED WITH IMMUNE-COMPLEXDEPOSITS

A 66-year-old Japanese male, who suffered from persistent proteinuria and leg edema, underwent renal biopsy. Light microscopy revealed marke d narrowing of the glomerular capillary lumen with a diffuse accumulat ion of weakly PAS-positive material. By electron microscopy, abundant abnormal collagen fibers were observed predominantly in the subendothe lial space and occasionally in the mesangial matrix, The fibers had a periodicity of about 60 nm and were immunoreactive for anti-type III c ollagen. Subendothelial electron-dense deposits were also found in som e of the capillary walls. The serum level of procollagen III peptides was elevated and changed in parallel with the amount of proteinuria du ring the patient's clinical course. On the basis of these findings, a diagnosis of the collagenofibrotic glomerulonephropathy was made. A re view of the literature, including 29 similar or identical cases, faile d to reveal the etiology and pathogenesis of this disease. We suggest that this disease may be divided into two different clinical subtypes, an adult-onset type and a pediatric type.