A challenge to achieve glycemic control in a patient with diabetes mellitus

Abstract

Secondary diabetes mellitus (DM) is a known identity with multiple causes. Acromegaly, a state of growth hormone (GH) excess, is a rare but an established cause of DM. Dysglycemia is present in approximately 50% of patients of acromegaly with impaired glucose tolerance (IGT) or impaired fasting glucose (IFG) ranging from 6% to 45% and from 7% to 22%, respectively, and DM has been reported in 16%–56% of patients (Alexopoulou O, Bex M, Kamenicky P, Mvoula AB, Chanson P, Maiter D. Prevalence and risk factors of IGT and DM at diagnosis of acromegaly: A study in 148 patients. Pituitary 2014;17:81-9; Dal J, Feldt-Rasmussen U, Andersen M, Kristensen LO, Laurberg P, Pedersen L, et al. Acromegaly incidence, prevalence, complications and long-term prognosis: A nationwide cohort study. Eur J Endocrinol 2016;175:181-90). Diabetes in these patients is usually severe and difficult to treat. Glycemic control in these patients is best achieved by treating the underlying GH excess. We report a 60-year-old female patient, case of somatotropinoma, who was referred to diabetic clinic in view of persistent hyperglycemia despite taking multiple antidiabetic medications along with high-dose basal-bolus insulin regimen. Patient had residual pituitary tumor with GH excess and clinically active disease. She was started with somatostatin analogs for the residual disease. Her blood sugar values improved dramatically with episodes of hypoglycemia in between. Patient was shifted to single oral hypoglycemic (OHA) along with low dose insulin. This case highlights the direct association between GH excess and its hyperglycemic effects. Following successful treatment of acromegaly with surgery, irradiation, or medical management, glucose tolerance improves; although complete resolution is rare, OHA/insulin requirement is dramatically reduced.