1996 Volume 39 Issue 10 Pages 797-802
A 42-year-old woman had been treated for chronic thyroiditis with L-thyroxine over a 20 year period. At the age of 40 years hyperglycemia and glycosuria were first noted at an annual medical check, at which time the patient had also noted acanthosis nigricans. At the time of admission, the patient had hypergammaglobulinemia, low levels of complement and an increased erythrocyte sedimentation rate. Anti-thyroglobulin antibody, anti-nuclear antibody (speckled pattern), anti-Scl-70 antibody, and anti-RNP antibody were all positive. An oral-glucose tolerance test revealed that plasma glucose levels were 141-412mg/dl, and that insulin levels and c-peptide levels were 350-1800, μU/ml and 8.9-31.0ng/ml, respectively. Thesuppression of plasma glucose andnon-esterified fatty acid by exogonous insulin infusion was impaired. Anti-insulin receptor antibodies were detected in her serum by the radioreceptor assay using human placenta membrane. Tests for anti-insulin antibody were negative. This report describes a very rare case showing preceding chronic thyroiditis and subsequently developed diabetes caused by anti-insulin receptor antibodies.
