The differential diagnosis of hyponatraemia is manifold and includes hormonal disorders such as primary adrenal insufficiency or hypothyroidism. The diagnosis of adrenal insufficiency is always suggestive in cases of hypotension associated with hyponatraemia, hyperkalaemia and metabolic acidosis. We herein report a case of severe hyponatraemia in a patient with Addison's disease. The underlying cause was disseminated adrenal tuberculosis without any evidence of other organ involvement. To date, tuberculosis remains a frequent cause of adrenal insufficiency although the pathophysiology of adrenal tropism is poorly understood.