Diabetic ketoacidosis in a case of pheochromocytoma

A 31-year-old woman was admitted to our hospital because of diabetic ketoac idosis (DKA). Ultrasound sonography revealed the existence of the left adre nal tumor and endocrinological examinations established a diagnosis of pheo chromocytoma. She had been healthy and there was no evidence for gestationa l diabetes in her personal history. Characteristic features were not found in her tumor size and the catecholamine levels as compared with typical cas es of pheochromocytoma. An overwhelming secretion of catecholamine might su ppress insulin secretion, as evidenced by the improvement after the resecti on of the tumor. However, a significant insulin resistance continued after tumor resection. Obesity and the heterozygosity of beta (3)-adrenergic rece ptor gene (Try64Arg) might play a role in insulin resistance, which resulte d in DKA at least in part. Literature survey revealed four cases of DKA in the patients with pheochromocytoma including ours, three of which were Japa nese. Pancreatic capacity to secrete insulin has been reported to be less t han Caucasians, which might be another reason for DKA. Thus, we speculate t hat both suppressed insulin secretion and insulin resistance deteriorated b y obesity or other factor(s) such as abnormality in beta (3) adrenergic rec eptor probably depress beta-cell function resulting in abnormal metabolic i mbalance such as DKA. (C) 2001 Elsevier Science Ireland Ltd. All rights res erved.