AIMS/HYPOTHESIS The aim of this study was to investigate the prevalence of fulminant type 1 diabetes and the clinical characteristics of the disease among newly diagnosed Korean patients.

METHODS Using data retrieved from the Seoul National University Hospital database, we identified all patients newly diagnosed with type 1 diabetes from 1 January 1999 to 31 July 2006. Information on clinical manifestations and laboratory data, including the presence of islet autoantibodies detected at diagnosis, were obtained by reviewing medical records.

RESULTS We identified 99 patients newly diagnosed with type 1 diabetes. Seven patients (7.1%) fulfilled the criteria for fulminant type 1 diabetes. Among the patients aged > or =18 years at onset, 30.4% had fulminant type 1 diabetes. Patients with this diabetes subtype tested negative for islet autoantibodies, had a higher age of onset (median 28 vs 10 years, p < 0.001) and a markedly shorter duration from onset of hyperglycaemic symptoms to first hospital visit (median 3 vs 30 days, p < 0.001) than patients with non-fulminant type 1 diabetes, and showed trends of increased serum aspartate aminotransferase and amylase levels and a decreased glucagon-stimulated serum C-peptide response.

CONCLUSIONS/INTERPRETATION In Korea, the prevalence of fulminant type 1 diabetes was 7.1% among all patients newly diagnosed with type 1 diabetes and 30.4% among patients with adult-onset diabetes. The clinical and metabolic characteristics of the patients with fulminant type 1 diabetes were similar to those reported in Japanese studies.