Summary

Many diseases can cause hypercalcaemia, including primary hyperparathyroidism, cancer, drugs and granulomatous diseases. A nursing home resident aged 81 years was admitted because of altered mental status. The patient did not have fever, cough, sputum or night sweat. Hypercalcaemia was identified as a cause of the consciousness disturbance. Chest radiograph showed no acute process. Laboratory workups revealed elevated serum levels of 1,25-(OH)2 vitamin D₃ and positive T-spot test. Microscopic examination of the suctioned sputum identified acid-fast bacilli, which was confirmed as Mycobactrium tuberculsosis. Tuberculosis should be considered as the important cause of hypercalcaemia since early diagnosis and treatment is recommended for preventing its outbreak among people with close contacts with patients.