A Case of Acute Psychosis in an Adolescent Male

Primary hyperparathyroidism (PHPT) is a disorder of calcium homeostasis. We report the case of a 17-year-old adolescent male, who presented with an acute psychosis coinciding with severe hypercalcemia and markedly elevated intact parathyroid hormone (iPTH) level and low vitamin D level. A Sestamibi scan showed a positive signal inferior to the left lobe of the thyroid gland. He had only a partial response to the initial medical and psychiatric management. The enlarged parathyroid gland was resected surgically and postoperatively serum calcium and iPTH levels normalized. The histopathology was compatible with a benign adenoma. Patient’s acute psychotic symptoms resolved gradually after surgery; however he remained under psychiatric care for the behavioral issues for about 6 months after surgery. While psychosis is a rare clinical manifestation of hypercalcemia secondary to PHPT in pediatric population, it should be considered as a clinical clue in an otherwise asymptomatic pediatric patient. 1. Introduction Primary hyperparathyroidism (PHPT) is a disorder of calcium homeostasis. It is rare in pediatric population (age < 18 years) and is usually caused by a single parathyroid adenoma (PA) [1–3]. PA has an incidence of 2–5 per 100,000 children [1]. Elevated levels of intact parathyroid hormone (iPTH) lead to persistent hypercalcemia. PA commonly involves the inferior parathyroid glands, although it can be found in several ectopic sites including thyroid gland, thymus, pericardium, and retroesophageal areas [4]. Hypercalcemia due to PA presents initially as nonspecific symptoms like polyuria, weakness, fatigue, irritability, anorexia, abdominal pain, nausea, emesis, and weight loss. Therefore, the diagnosis of hypercalcemia is often delayed due to subtle clinical symptoms until the complications emerge [1]. These include renal stones, osteopenia and osteoporosis, osteitis fibrosa cystica, peptic ulcer disease, pancreatitis, constipation, hypertension, arrhythmias (shortening of QT interval) [5], and neuropsychiatric diseases [6]. PHPT should be included in the differential diagnosis of all cases of hypercalcemia. Common causes of hypercalcemia include William’s syndrome, idiopathic infantile hypercalcemia, malignancy, and toxicity with drugs like thiazides and vitamin A. Rare causes include familial hypocalciuric hypercalcemia, multiple endocrine neoplasia I and II syndromes, subcutaneous fat necrosis, granulomatous disorders, hypervitaminosis D, malignancies, adrenal insufficiency [7], hyperthyroidism, hypothyroidism, and limb fracture with immobilization