Primary hypoadrenalism assessed by the 1 mu g ACTH test in hospitalized patients with active pulmonary tuberculosis

Primary hypoadrenalism, assessed by 250 mu g ACTH stimulation, is uncommon in patients with active pulmonary tuberculosis (PTB). Since 1 mu g ACTH pro duces an equivalent + 30 min cortisol response to 250 mu g in control subje cts, the 250 mu g dose is supraphysiological and may lack sensitivity for t he diagnosis of hypoadrenalism. Furthermore, the impact of coexistent HIV i nfection on the prevalence of primary hypoadrenalism in PTB is uncertain. W e thus determined the cortisol response to an intravenous bolus of 1 mu g A CTH in 21 controls, 18 HIV-positive (BMI 19.5 +/- 0.9 kg/m(2), albumin 24+/ -1.4 g/l, CD4 count 192+/-47/mm(3)) and 22 HIV-negative (BMI 19.3+/-0.8 kg/ m(2), albumin 29+/-1 g/l, CD4 count 652+/-76/mm(3)) patients with active PT B, The mean basal cortisol was greater in patients than in controls (559 vs . 373 nmol/l, p = 0.0009). The mean cortisol after 1 mu g ACTH stimulation did not, however, differ significantly when comparing either patients and c ontrols or patients who were HIV-positive and -negative (p > 0.05). Using t he minimum + 30 min cortisol derived from the 21 controls as a marker of no rmal adrenal function (414 nmol/l), a single patient was classified as hypo adrenal. In conclusion, primary hypoadrenalism, as assessed by the 1 mu g A CTH test, is uncommon in a cohort of ill, hospitalized patients with active PTB, irrespective of HIV status.