Parathyroid Cyst Presenting as Acute Pancreatitis: Report of a Case
A 67-year-old man was admitted to Chonnam National University Hospital with sudden onset of epigastric pain. The pain did not radiate along his back but was relieved to some extent by his leaning forward. He had a history of diabetes mellitus, essential hypertension, and an old cerebrovascular accident. He had no previous history of peptic ulcer diseases, cholecystitis with gallstones, any alcohol ingestion, or abdominal surgery. On admission, he was afebrile, his blood pressure and pulse were normal, and he appeared well-nourished. Scleral icterus was not present. His abdomen was mildly distended, with tenderness in the epigastrium. No abdominal masses were seen; the liver, gallbladder, and spleen were not palpable; and bowel sounds were slightly hyperactive. Laboratory indexes were as follows: white blood cell count, 9,000/mm3; hemoglobin, 15.7 g/dl; platelet count, 135,000/mm3; serum albumin, 4.4 g/dl; aspartate aminotransferase, 29 U/L; alanine aminotransferase, 29 U/L; alkaline phosphatase, 84 U/L; and γ-glutamyl transpeptidase, 148 U/L. Serum amylase and lipase were 293 U/L and 660 U/L, respectively. C-reactive protein was 2.6 mg/dl. The results of the renal function study were within normal limits. Serum triglyceride was 93 mg/dl and serum total calcium, ionized calcium, and inorganic phosphate were 10.3 mg/dl, 2.8 mEq/L, and 1.9 mg/dl, respectively. Abdominal computed tomography (CT) revealed mild swelling of the pancreatic head with peri-pancreatic fat infiltration () and fluid collection around the pancreatic tail (). The follow-up serum ionized calcium level was still elevated at 3.0 mEq/L. The serum level of parathyroid hormone (PTH) was 113 pg/ml. The results indicated hypercalcemia caused by hyperparathyroidism.\nUltrasonography and CT of the neck showed an approximately 5-cm cystic lesion at the inferior portion of the left thyroid gland, which suggested a parathyroid cyst (). The fine needle aspiration biopsy specimen suggested a cystic lesion. 99mTc sestamibi scintigraphy showed no evidence of parathyroid adenoma. The patient had prolonged hypercalcemia despite hydration and diuretics. He underwent surgical resection, and the histological examination with PTH stain was interpreted as a parathyroid cyst with focal parathyroid hyperplasia ().\nAt 3 weeks after the operation, his serum levels of PTH, total calcium, ionized calcium, inorganic phosphate, amylase, and lipase were normalized. Since the operation, he has had no recurrent episodes of acute pancreatitis.