The article presents the latest diabetes mellitus (DM) classification proposed by WHO in 2019 according to which new types of DM are identified. The hybrid forms and the unclassified DM form identification is due to difficulties in establishing the diagnosis and presence of the disease forms not meeting the generally accepted criteria. The hyperglycemia first detected during pregnancy type combining the DM pre-gestational and the gestational types has been isolated. Criteria for the diagnosing slowly evolving, immunity-mediated diabetes of adults and potential treatment options are discussed.
To optimize the DM diagnosis, modern diagnostic criteria for various types of DM are presented.