Metabolic and immunologic features of Chinese patients with atypical diabetes mellitus

OBJECTIVE, - To determine whether atypical diabetes mellitus (ADM) is prese nt in the Chinese population in Hong Kong. RESEARCH DESIGN AND METHODS - The records of Chinese patients who attended the Diabetes Clinic at Queen Mary Hospital were reviewed. We identified 11 patients who initially presented with acute diabetic ketoacidosis but subse quently displayed clinical features more typical of type 2 diabetes. Metabo lic studies and HLA typing were performed to characterize this group of Chi nese patients with ADM. RESULTS - C-peptide response of the patients with ADM 1 h after a standard meal was intermediate between that of type 1 diabetic patients (matched for age and duration of diabetes) and that of nondiabetic control subjects (ma tched for age and BMI) (analysis of variance, P = 0.02). Insulin sensitivit y measured by a short insulin tolerance test was not significantly differen t between patients with ADM and their matched nondiabetic control subjects. HLA typing showed that none of the patients with ADM had the DR3 allele an d that the frequency of DR9 was not increased. Only one patient had signifi cantly increased levels of antibodies to GAD and islet cell antigen 512. CONCLUSIONS - ADM, which was first described in African-Americans, is seen also in Chinese subjects. These patients have significant residual C-peptid e secretory capacity and should not be misdiagnosed and treated as patients with type 1 diabetes with life-long insulin therapy.