The endocrinology of adrenal tuberculosis: the effects of tuberculosis on the hypothalamo-pituitary-adrenal axis and adrenocortical function

Abstract

Tuberculosis may affect many of the endocrine glands including the hypothalamus, pituitary, thyroid and adrenals. The most commonly involved endocrine organ in tuberculosis is the adrenal gland. Adrenal glands may be directly or indirectly affected by tuberculosis. Tuberculous Addison's disease is still an important cause of primary adrenocortical insufficiency particularly in the developing countries. Recent improvements in imaging techniques and modern endocrinological tests for the investigation of adrenal function have given us greater insight into the endocrinology of adrenal tuberculosis. Hypothalamo-pituitary-adrenal (HPA) axis is also involved in tuberculosis and recent findings revealed that HPA axis is activated rather than underactivated in active pulmonary tuberculosis. Activated HPA axis in tuberculosis causes increased cortisol secretion which results in a shift in the Th1/Th2 balance towards Th2. T cell dysfunction due to high cortisol and low DHEAS levels may be responsible for immunologically-mediated tissue damage in tuberculosis. In this review, recent findings concerning the adrenocortical function, radiological changes in adrenal glands and HPA axis involvement in tuberculosis are discussed.