BACKGROUND: Rapid adrenocorticotropin (ACTH) stimulation test using 250ug of ACTH (1-24) has been used as a standard test in the initial assessment of adrenal function. However, it has recently been suggested that a rnaximal cortisol response can be achieved with a much lower ACTH dose, and reducing the dose might further enhance the sensitivity of the test in the detection of mild adrenal insufficiency. This study was performed to evaluate the role of low-dose (lug) ACTH stimulation test in the assessment of adrenal function and the diagnosis of subtle adrenal insufficiency. METHODS: Twenty-two subjects with suspected adrenal insufficiency due to long-term corticosteroid use were included in this study. The correlations between clinical features and the serum cortisol responses to low dose (lug) and high dose (250 ug) ACTH stimulation were evaluated. RESULTS: In high dose test, 10 (67%) out of 15 subjects with clinical features of adrenal insufficiency showed decreased serum cortisol response (peak cortisol level <18 ug/dL), but 5 (33%) subjects showed normal response (peak cortisol level > 18ug/dL). On the other hand, 14 (93%) subjects with clinical features of adrenal insufficiency showed decreased serum cortisol response in low dose test, while only one showed normal response. In 7 subjects without clinical features of adrenal insufficiency, 5 subject (71%) showed normal response, and 2 subjects (29%) showed decreased response in both low and high dose tests. CONCLUSION: These results suggest that the 1-ug low dose ACTH stimulation test might be more sensitive than conventional 250-ug test in the detection of mild adrenal insufficiency. Further studies are needed to determine the optimal dose of ACTH and the criteria for normal response to ACTH stimulation.
Adrenal Insufficiency* ; Adrenocorticotropic Hormone* ; Cosyntropin ; Diagnosis* ; Hand ; Hydrocortisone

BACKGROUND: Inhaled glucocorticoids are the medical treatment of choice in asthma patients. Fluticasone propionate is one of the most effective inhaled corticosteroids and has been reported to have minimal effect on the hypothalamic-pituitary-adrenal axis at the recommended dose. However, reports of long-term trials characterizing their systemic safety with chronic use are rare. This study was designed to evaluate the long-term safety of inhaled fluticasone propionate to the hypothalamic-pituitary-adrenal axis. METHOD: This study was conducted on 21 patients to evaluate the adrenal response to rapid ACTH stimulation test after 6 months of treatment with fluticasone propionate from 200 µg to 750 µg daily. The serum cortisol levels was measured to assess its effect on the hypothalamic-pituitary-adrenal axis just prior to the injection, at 30 minutes and 60 minutes after an intramuscular injection of synthetic ACTH. RESULT: The mean dose of inhaled fluticasone propionate was 355 µg per day(SD=174 µg, range=200 µg to 750 µg). The mean serum cortisol levels of the patients was 11.0 µg/dl(SD=6.4 µg/dl) prior to the injection, 20.0 µg/dl(SD=7.7 µg/dl) after 30 minutes, and 23.0 µg/dl(SD=6.3 µg/dl) after 60 minutes. Sixteen patients of the 21 patients had a normal response(>18 µg/dl), and 5 out of the 21 patients had serum cortisol levels below the normal range after the rapid ACTH stimulation test. CONCLUSION: Adrenal suppression occurred in 5 out of 21 patients with 6 months treatment with inhaled fluticasone propionate.
Adrenal Cortex Hormones ; Adrenocorticotropic Hormone ; Asthma* ; Axis, Cervical Vertebra* ; Cosyntropin ; Diethylpropion* ; Glucocorticoids ; Humans ; Hydrocortisone ; Injections, Intramuscular ; Reference Values ; Fluticasone