Intrathyroidal parathyroid carcinoma: Putting the pieces together

Case history: A 37-year-old previously fit and well Bangladeshi man presented with a 3-week history of mood changes, muscle and bone pain, fatigue and thirst. Examination was essentially normal. He had a biochemical picture consistent with primary hyperparathyroidism with raised serum calcium (3.23mmol/L), low phosphate (0.39mmol/L), raised parathyroid hormone (31.3pmol/L), low vitamin D3 (31nmol/L) and raised urinary calcium (14.7mmol/day). His thyroid function was normal. His hypercalcaemia was refractory to medical management.