Membranous nephropathy, antitubular basement membrane antibodies and alveolar hemorrhage in a diabetic child.

: We describe an 8-year-old boy who was diagnosed as having diabetes mellitus at the age of 3 months. During the follow-up the diabetes was uncontrolled, and he presented nephrotic syndrome with renal function impairment, a renal biopsy showing a membranous nephropathy. Subsequently he had episodes of anemia and dyspnea, due to alveolar hemorrhage, and he also developed Fanconi's syndrome. A later renal biopsy showed membranous glomerulonephritis and interstitial nephritis. The presence of antitubular basement membrane antibodies was noted but antialveolar basement membrane antibodies were not detected. We do not believe that this unusual clinical picture was a coincidence, and we speculate about a possible explanation.