SummaryA 44-year-old man with headache, sweating, subfebrile temperature and profound fatigue was found to have hypercalcaemic crisis with renal failure. Despite standard therapy, calcium levels remained high, he became anuric and developed multi-organ failure with acute respiratory distress syndrome requiring high ventilatory support, norepinephrine, dobutamine and continuous veno-venous haemodiafiltration. Ectopic calcification was found in the lungs, in the thyroid, kidneys, heart and stomach. A large parathyroid adenoma was then removed. When last seen, 11 months after surgery, the patient no longer required oxygen, and total lung capacity had returned to normal. BACKGROUND