DIDMOAD syndrome is defined by diabetes insipidus, diabetes mellitus, optic atrophy, and deafness.1 It is inherited as an autosomal recessive trait with varying expressivity. We report an interesting case involving a patient with type 1 diabetes with DIDMOAD syndrome–like manifestations.
A 74-year-old woman (height, 146 cm; body weight, 37.4 kg) presented with DIDMOAD syndrome–like manifestations. Two of her 3 children had diabetes mellitus, but her parents and siblings did not. She developed diabetes mellitus, diabetes insipidus, and deafness when she was 50, 72, and 60 years old, respectively. She had been treated with diet and oral hypoglycemic agents for 10 years before she required insulin. At presentation, her fasting serum C-peptide level was 0.8 nmol/1 (2.4 ng/mL) (reference range, 0.3-0.8 nmol/L [0.9-2.4 ng/mL]). The results of laboratory investigations, including liver and renal function tests and measurement of serum lactate and pyruvate levels, were within normal ranges. Antibodies to glutamic acid decarboxylase were detected at 53.3 U/mL (normal, <1.5 U/mL), and anti-insulin antibodies were detected at 0.49 (normal, <0.10). The patient's HLA haplotytpes were as follows: HLA-A24, -A2, -B54, -B48, -Cw 1, -DR6, and -DR2. Optic fundscopy revealed progressive diabetic retinopathy without optic atrophy. The patient suffered from diabetic polyneuropathy and showed evidence of microalbuminuria. Chest radiography, electrocardiography, and ultrasonography of the abdomen revealed no abnormalities.