Ketosis-prone diabetes mellitus: A phenotype that hospitalists need to understand

Table 1 Aß system for four ketosis-prone diabetes subgroups based on the presence/absence of autoantibodies and ß cell function

	A+: Anti-GAD65 and IA-2 antibodies present in serum	A-: Anti-GAD65 and IA-2 antibodies not present in serum
ß+: Fasting serum C-peptide concentration greater than or equal to 1 ng/mL (0.33 nmol/L) or a peak serum C-peptide response to glucagon greater than or equal to 1.5 ng/mL (0.5 nmol/L)	A+ß+: Autoantibodies present, beta cell function present	A-ß+: Autoantibodies absent, beta cell function present
ß-: Fasting serum C-peptide concentration is less than 1 ng/mL (0.33 nmol/L) or a peak serum C-peptide response to glucagon less than 1.5 ng/mL (0.5 nmol/L)	A+ß-: Autoantibodies present, beta cell function absent	A-ß-: Autoantibodies absent, beta cell function absent

GAD65: Glutamic acid decarboxylase; IA-2: Anti-islet tyrosine phosphatase 2.