We report glomerular lesions in 2 siblings presenting a juvenile cystinosis. Kidney biopsy in one of them showed focal, segmental, mesangial proliferative and hyalinosis lesions, and the second showed segmental juxtahilar hyalinosis in one third of glomeruli. Neither of the 2 patients displayed a Toni-Debre-Fanconi syndrome. In one of the patients, cystine crystals were found by means of electronic microscopy. The first patient developed chronic renal failure and a kidney transplantation was performed. No recurrence of the cystine deposits was observed in the graft. Pedigree of the described family seems to be in accordance with an autosomal dominant pattern of inheritance.