INS and Impaired glucose tolerance: The incidence of diabetes among patients with PPGL ranges from 21% to 37%,[36] with a higher prevalence of impaired glucose tolerance (approximately 49.5%).[37] Diabetic ketoacidosis and hyperosmolar hyperglycemic coma can also occur.[29,38] The main reasons for impaired glucose tolerance in PPGL are impaired insulin secretion and increased insulin resistance.[39] Moreover, different catecholamine secretion phenotypes in PPGL have varying effects on impaired glucose tolerance.