Endocrine Abstracts

Introduction: Tuberculosis is a granulomatosis with systemic manifestations. Pulmonary involvement is usually in the foreground. Rarely, hypercalcaemia initiates the pathology. The incidence of hypercalcaemia in tuberculosis varies according to studies and regions between 2 and 25%, with the highest incidences in the most isolated countries and those with the highest calcium and vitamin D intakes.

Clinical Case: This is the case of our patient known for basedow’s disease treated by iratherapy; 3 years after stabilization of her hyperthyroidism she presents a frank hypercalcemia. The hormonal exploration is in favour of an extra parathyroid hypercalcaemia. Cervical ultrasound revealed a granulomatous left supra-clavicular adenopathy which was punctured in favour of lymph node tuberculosis. 3 months after the start of anti-tuberculosis treatment, the blood calcium level was normalized.

Conclusion: In tuberculosis, hypercalcaemia is due to extrarenal synthesis of 1,25(OH)2- vitamin D3 by granuloma macrophages with 1-alpha hydroxylase activity. Within the granulomas, the binding of 1,25(OH)2-vitamin D3 to its specific receptors modulates the immune response and decreases the inflammatory response that causes tissue damage.