Renal failure in two patients with Wolfram syndrome

We describe a Thai family with three children, two of whom presented with Wolfram syndrome, which is a rare syndrome characterised by diabetes insipidus, diabetes mellitus, optic atrophy, deafness and urinary tract dilatation. A girl and her younger brother had insulin-dependent diabetes mellitus at 11 years old with early onset of renal impairment, proteinuria and hypertension. Urinary tract dilatation was demonstrated in both patients. Kidney biopsies were compatible with diabetic nephropathy. Both children also had bilateral sensorineural hearing loss. Optic atrophy with severe loss of vision was detected in the girl and bilateral cataract in her brother. Both patients were HLA DR2 positive. At 16 years old, her creatinine clearance was 16 ml/min/1.73 m2. Her brother's creatinine clearance was 25 ml/min/1.73 m2 at 13 years old. We conclude that renal function should be evaluated in patients with Wolfram syndrome and the cause of renal failure in these patients may be rapid and severe diabetic nephropathy.