Narrative review: ketosis-prone type 2 diabetes mellitus.

Several investigators have reported that more than half of African-American persons with new diagnoses of diabetic ketoacidosis have clinical, metabolic, and immunologic features of type 2 diabetes during follow-up. These patients are usually obese, have a strong family history of diabetes, have a low prevalence of autoimmune markers, and lack a genetic association with HLA. Their initial presentation is acute, with a few days to weeks of polyuria, polydipsia, and weight loss and lack of a precipitating cause of metabolic decompensation. At presentation, they have markedly impaired insulin secretion and insulin action, but intensified diabetic management results in significant improvement in beta-cell function and insulin sensitivity sufficient to allow discontinuation of insulin therapy within a few months of follow-up. On discontinuation of insulin therapy, the period of near-normoglycemic remission may last for a few months to several years. The absence of autoimmune markers and the presence of measurable insulin secretion have proven useful in predicting near-normoglycemic remission and long-term insulin dependence in adult patients with a history of diabetic ketoacidosis. This clinical presentation is commonly reported in African and African-American persons but is also observed in Hispanic persons and those from other minority ethnic groups. The underlying mechanisms for beta-cell dysfunction in ketosis-prone type 2 diabetes are not known; however, preliminary evidence suggests an increased susceptibility to glucose desensitization.