The hereditary features of renal disease have engendered much interest since the turn of the century. Hereditary cystic renal disease, abnormalities in both proximal and distal tubular function, chronic glomerulonephritis, nephrosis, congenital anomalies, and tumors of the genitourinary tract are well documented and were the subject of a recent review by Perkoff.1
This paper describes a family with persistent microscopic hematuria of glomerular origin without nephritis, deafness, ocular lesions, impairment of renal function, or other congenital anomalies. An unusual structural abnormality, thin glomerular capillary basement membranes, was a constant finding in this kindred and may be the cause of the hematuria.
Hematuria is usually considered a serious symptom, and its presence calls for meticulous investigation. The diagnosis of "idiopathic" or "essential" hematuria is a diagnosis of exclusion, and can be made only when no cause for the hematuria is found after exhaustive investigation. The abnormality causing the hematuria can