The Case | Hexadactyly, blindness, obesity, and end-stage renal disease

A 39-year-old man with mental retardation, diabetes mellitus (DM), and end-stage renal disease (ESRD) on chronic hemodialysis was referred for blood-glucose control. His medical history indicated congenital hexadactyly and developmental delay, with speech and walking delay at the age of 5 and 6 years, respectively. He had degraded vision since 17 years old, which progressed to blindness at 28 years of age. At 18 years of age, impaired renal function (serum creatinine, 1.9 mg/dl) without proteinuria was noted, and kidney echography revealed bilateral increased echogenicity and decreased size. Renal function deteriorated gradually to ESRD, with daily proteinuria of 0.9 g, at 37 years of age. No kidney biopsy was performed. He had obese features since childhood and developed type II DM at 34 years of age. On examination, it was found that he had a high body mass index at 33.3 kg/m2, showed postaxial hexadactyly and brachydactyly of the four limbs (Figure 1), and a 2.5-cm micropenis. Fundus examination revealed retinitis pigmentosa (Figure 2). Echocardiogram and brain computed tomography were unremarkable.