2019 Volume 62 Issue 12 Pages 755-762
A female infant with unrelated healthy parents was delivered at 1,511 g in weight at 37 weeks of gestation with intrauterine growth retardation. At 10 years of age, glycosuria was detected in an in-school routine medical examination; she was then referred to our hospital. Her height at that time was −1.76 standard deviations (SD), and her obesity degree was −24 %. Because she had hirsutism, acanthosis nigricans, teeth malalignment, hyperglycemia, high glycated hemoglobin, hyperinsulinemia, and negative anti-glutamic acid decarboxylase antibody/anti-insulin antibody, she was suspected of having an insulin receptor abnormality. Using the Sanger sequencing method, her insulin receptor gene showed two compound heterozygote mutations in exon 12, and we diagnosed her with Rabson-Mendenhall syndrome. We administered insulin-like growth factor-I (IGF-I) therapy because her condition did not improve with diet, exercise therapy, biguanide drug, or α-glucosidase inhibitor. Her compound hetero mutations in exon 12 were both at the FnIII-2 region, far from the folded nucleus1). We experienced a case of slowly progressive Rabson-Mendenhall syndrome in which the mutations were analyzed.
