Hypercalcaemia and hypercalciuria were diagnosed in a 21-week-old boy with miliary tuberculosis. The tuberculosis was treated with isoniazid, rifampin and streptomycin. After 2 months, streptomycin was replaced by ethambutol. The hypercalcaemia was treated initially with prednisone, which decreased the serum 1.25 (OH)2 cholecalciferol level but the serum calcium level remained unaltered. After calcium and vitamin D restriction, the serum calcium level normalized within 1 day. The patient's tuberculosis was treated and he remains well.