ACTH Uyarı Testinde Kortizol Pik Yanıtı Zamanının Belirlenmesi

Abstract

Adrenocorticotropic hormone (ACTH) stimulation test is widely used in diagnosis of adrenal insufficiency. Synthetic ACTH analogue has two formulations: Short-acting intravenous or intramuscular form and intramuscular depot form. In the standard ACTH stimulation test protocol, 250μg synthetic ACTH (1-24) is administered intravenously. Blood samples are then taken at 0, 30, 60 and 90 minutes for cortisol. We aimed to determine the time of cortisol peak response by evaluating cortisol responses to intramuscular depot ACTH. Seventy patients who underwent ACTH stimulation test between October 2017 and February 2019 in Eskişehir Osmangazi University Endocrinology Department were included to the study. 250 mcg intramuscular depot ACTH was administered between 08.00-09.00 a.m. Blood samples were taken before ACTH administration and at 30, 60, 120, 240 minutes. Cortisol levels 18 mcg/dl and above was accepted as normal response. Since 20 mcg / dl and above are accepted as normal response in different publications, evaluation was also made on this value. The highest cortisol level was reached in 240 minutes in all patients. If normal cortisol response is accepted as 20 mcg/dl and above, 38 patients reached normal cortisol values at 30th minute, 12 patients at 60th minute, 6 patients at 120th minute. If normal cortisol response is accepted as 18 mcg/dl and above, 38 patients reached normal cortisol values at 30th minute, 10 patients reached normal cortisol values at 60th minute, 2 patients reached 120th minute. In both groups, only one patient was able to reach the target cortisol value after prolongation to 240 minutes. We suggest that prolongation of the stimulation test with intramuscular depot ACTH up to 120 minutes may prevent patients from being misdiagnosed with adrenal insufficiency, but prolongation to 240 minutes will not provide additional benefit.