Juvenile Nephronophthisis with Blindness in a Three-month-old Infant

Juvenile nephronophthisis is a slowly progressive renal disease with onset in infancy, char acterized by impaired renal concentrating ability. The combination of juvenile nephronophthisis and tapeto-retinal degeneration, renal-retinal dystrophy, may cause blindness in infancy, and renal failure in the first decade of life. This syndrome has not been previously described as a cause of renal failure in young infants. We report an infant who presented at three months of age with blindness and renal insufficiency. In addition, this infant had a disproportionate degree of hypocalcemia and hyperphosphatemia compatible with relative parathyroid gland insuffi ciency. We propose that this was due to an inability of this infant's parathyroid glands to undergo compensatory hypertrophy, rather than a specific defect in parathyroid function as sociated with renal-retinal dystrophy.