A 31-year-old Hispanic male, presented to Emergency Department with nausea and vomiting associated with intermittent blurry vision for 4 days. He also noted malaise, epigastric pain, polyuria, polydipsia and about 40lb unintentional weight loss in the last two years. He reported no significant past medical history, no home medication and no family history of diabetes. Physical exam revealed a dehydrated patient with tachycardia, Kussmaul’s breathing with macroglossia, macrognathia, as well as enlargement of the hands and feet. There was no vision change or field deficit on ophthalmologic examination. His lab results on admission showed elevated blood glucose (662 mg/dL), Anion gap of 22, pH of 7.12 and bicarbnate of 6 mEq/L. Urine analysis revealed elevated ketone and his beta-hydroxybutyrate was 10.5 mmol/L. Patient was admitted to intensive care unit and started on DKA protocol. His HbA1C was found to be elevated at 13.3% with low C peptide (0.6 ng/ml). Patient was clinically improved with rehydration and insulin infusion. His acidosis resolved within 24 hours. Acromegaly was later confirmed by laboratory studies (IGF-1=399 ng/ml). Pituitary magnetic resonance imaging disclosed the presence of a non-enhancing pituitary mass (29x16x22 mm) with no compression of optic chiasm. Additional laboratory findings included mildly elevated prolactin of 27.2 ng/ml and testosterone of 55 ng/dL. Other hormonal profile was normal. Transphenoidal adenomectomy was planned for the treatment of pituitary macroadenoma.
Glucose intolerance and diabetes mellitus are commonly seen in patients with acromegaly. However, DKA is a rare complication of acromegaly. The underlying pathophysiology for DKA in such cases is not very well understood. Evidence suggests that both GH and IGF-1 excess induce insulin resistance and increase glycogenolysis / gluconeogenesis. It has been suggested the ongoing high level of blood glucose of undiagnosed acromegaly contributes to glucotoxicity and beta-cell failure. Furthermore, glucagon is considered to be a contributing factor together with insulin deficiency. It is also suggested that high GH and IGF-1 levels increase lipolysis and lead to ketosis, which later lead to DKA.
Acromegaly is a rare endocrine disorder, secondary to hypersecretion of growth hormone (GH) and insulin-like growth factor-1 (IGF-1). Although impaired glucose tolerance affects about one third of patients with acromegaly, diabetes ketoacidosis (DKA) is rarely reported. Surgical removal of the tumor is usually the first choice. Acromegaly is nearly always caused by a pituitary adenoma. Impaired glucose tolerance or diabetes mellitus often resolve with treatment of acromegaly.