symptoms of type 1 diabetes

1. Immune-mediated type 1 diabetes mellitus —
Immune-mediated type 1 diabetes is felt to result from an infectious or toxic insult to persons whose immune system is genetically predisposed to develop a vigorous autoimmune response either against altered pancreatic B cell antigens or against molecules of the B cell resembling the viral protein (molecular mimicry). Extrinsic factors that affect B cell function include damage caused by viruses such as mumps or coxsackie B4 virus, by toxic chemical agents, or by destructive cytotoxins and antibodies released from sensitized immunocytes. Specific HLA immune response genes are believed to predispose patients to a destructive autoimmune response against their own islet cells (autoaggression), which is mediated primarily by cytotoxic T cells. Amelioration of hyperglycemia in patients given an immunosuppressive agent (eg, cyclosporine) shortly after onset of type 1 diabetes lends further support to the pathogenetic role of autoimmunity.
2. Idiopathic type 1 diabetes mellitus —
Fewer than 10% of subjects have no evidence of pancreatic B cell autoimmunity to explain their insulinopenia and ketoacidosis. This subgroup has been classified as "idiopathic type 1 diabetes" and designated as "type 1B." Although only a minority of patients with type 1 diabetes fall into this group, most of these are of Asian or African origin.