The specificity of split renal membranes in hereditary nephritis.

This study was undertaken to assess the specificity of split renal basement membranes in hereditary nephritis (HN). Thirteen specimens from eight patients with HN were mixed in a random fashion with specimens from control patients with either idiopathic nephrotic syndrome or various forms of glomerulonephritis and with specimens from patients with benign recurrent hematuria (BRH). Each biopsy specimen was scored for splitting of glomerular basement membranes (GBMs). Control and BRH specimens contained focal splitting in the GBMs; the biopsy specimens from HN patients had widespread lesions. Evaluation of split GBMs is useful in differentiating patients with HN from those with BRH and other renal diseases that may be confused with HN.