Hamideh Akbari1,2, Mohammad Ghorbani3, Maryam Kabootari1, Ali Zare Mehrjardi2, Mohammad Reza Mohajeri Tehrani4, Mojtaba Malek5, Mohammad E Khamseh2. 1. Clicical Research Development Unit, Sayad Shirazi Hospital, Golestan University of Medical Sciences, Gorgan, Iran. 2. Endocrine Research Center, Institute of Endocrinology and Metabolism, Iran University of Medical Sciences (IUMS), Tehran, Iran. 3. Division of Vascular and Endovascular Neurosurgery, Firoozgar Hospital, Iran University of Medical Sciences (IUMS), Tehran, Iran. 4. Endocrinology and Metabolism Research Center, Tehran University of Medical Sciences, Tehran, Iran. 5. Research Center for Prevention of Cardiovascular Disease, Institute of Endocrinology and Metabolism, Iran University of Medical Sciences (IUMS), Tehran, Iran.
Abstract
Background: Bilateral inferior petrosal sinus sampling (IPSS) is used to distinguish pituitary from ectopic adrenocorticotropin (ACTH) excess in patients with ACTH-dependent Cushing's syndrome. Our objective was to examine the utility of prolactin measurement during IPSS with desmopressin (DDAVP) stimulation in localization of the source of ACTH excess.Method: Retrospective review of 20 patients with ACTH-dependent Cushing's syndrome who underwent IPSS with DDAVP stimulation. Baseline, DDAVP-stimulated, and prolactin-normalized ACTH IPS:P (inferior petrosal sinus to peripheral) ratios were calculated. Cut-off values for each test were obtained from receiver-operating characteristic (ROC) curve analysis. Results: Fifteen patients had Cushing disease (CD), and five were diagnosed with ectopic ACTH syndrome (EAS). For the baseline ACTH IPS:P ratio of ≥2, the diagnostic sensitivity (80%), specificity (100%), positive predictive value (PPV) (100%) and negative predictive value (NPV) (62.5%) were calculated. These values for DDAVP-stimulated IPS:P ACTH ratio ≥ 3, were 86.7%, 100%, 100% and 71.4%, respectively. The corresponding value for the prolactin-normalized ACTH IPS:P ratio ≥ 0.8 were 86.6%, 80%, 92.8% and 66.7%. The cut-off value for the baseline, DDAVP-stimulated and prolactin-normalized ACTH IPS:P ratios were 1.76, 3.9, and 0.33, respectively. Conclusion: Prolactin-normalized ACTH IPS:P ratio measurement showed comparable sensitivity and less specificity than baseline/DDAVP-stimulated IPS/P ACTH ratios. Moreover, when baseline and stimulated IPS/P ACTH tests were discordant, prolactin-normalized ACTH IPS: P ratio correctly localized the source of ACTH excess. The sensitivity of the test increased, applying a prolactin-normalized ACTH IPS: P ratio ≥0.33.
Background: Bilateral inferior petrosal sinus sampling (IPSS) is used to distinguish pituitary from ectopic adrenocorticotropin (ACTH) excess in patients with ACTH-dependent Cushing's syndrome. Our objective was to examine the utility of prolactin measurement during IPSS with desmopressin (DDAVP) stimulation in localization of the source of ACTH excess.Method: Retrospective review of 20 patients with ACTH-dependent Cushing's syndrome who underwent IPSS with DDAVP stimulation. Baseline, DDAVP-stimulated, and prolactin-normalized ACTH IPS:P (inferior petrosal sinus to peripheral) ratios were calculated. Cut-off values for each test were obtained from receiver-operating characteristic (ROC) curve analysis. Results: Fifteen patients had Cushing disease (CD), and five were diagnosed with ectopic ACTH syndrome (EAS). For the baseline ACTH IPS:P ratio of ≥2, the diagnostic sensitivity (80%), specificity (100%), positive predictive value (PPV) (100%) and negative predictive value (NPV) (62.5%) were calculated. These values for DDAVP-stimulated IPS:P ACTH ratio ≥ 3, were 86.7%, 100%, 100% and 71.4%, respectively. The corresponding value for the prolactin-normalized ACTH IPS:P ratio ≥ 0.8 were 86.6%, 80%, 92.8% and 66.7%. The cut-off value for the baseline, DDAVP-stimulated and prolactin-normalized ACTH IPS:P ratios were 1.76, 3.9, and 0.33, respectively. Conclusion:Prolactin-normalized ACTH IPS:P ratio measurement showed comparable sensitivity and less specificity than baseline/DDAVP-stimulated IPS/P ACTH ratios. Moreover, when baseline and stimulated IPS/P ACTH tests were discordant, prolactin-normalized ACTH IPS: P ratio correctly localized the source of ACTH excess. The sensitivity of the test increased, applying a prolactin-normalized ACTH IPS: P ratio ≥0.33.
Authors: Mohammad Ghorbani; Hamideh Akbari; Christoph J Griessenauer; Christoph Wipplinger; Alireza Dastmalchi; Mojtaba Malek; Iraj Heydari; Reza Mollahoseini; Mohammad E Khamseh Journal: Heliyon Date: 2020-10-22