Reliability of Subtype Diagnosis of Primary Aldosteronism Associated with Hypercortisolism in Adrenal Vein Sampling

Presentation Number: SUN 509
Date of Presentation: April 2nd, 2017

Yumiko Sasai*1, Hironobu Umakoshi1, Mika Tsuiki1, Mitsuhide Naruse1, Isao Kurihara2, Takanobu Yoshimoto3 and Tomikazu Fukuoka4
1National Hospital Organization Kyoto Medical Center, Kyoto, Japan, 2Keio University School of Medicine, Tokyo, Japan, 3Tokyo Medical and Dental University, Tokyo, Japan, 4Matsuyama Red Cross Hospital, Matsuyama, Japan

Abstract

Background: Hypercortisolism (HC) could lead to misinterpretation for the subtype diagnosis of primary aldosteronism (PA) in adrenal vein sampling (AVS), because HC might affect the cortisol secreting gradients between tumor and non-tumor side. However, it is unknown which criteria for lateralization can be adopted in PA patients associated with HC (PA-HC).

Objective: We aimed to assess the prevalence of PA-HC and the reliability of subtype diagnosis of PA-HC from post-operative outcomes from JPAS database.

Design, Setting and Patients: In this multicenter, cross-sectional, retrospective study, we included patients with PA who underwent computed tomography and 1mg dexamethasone test at 24 referral centers in Japan between 2006 and 2016. Patients were defined as having HC when serum cortisol level were greater than 1.8 μg/dl after 1mg dexamethasone test. In addition, we assessed the relationships between prevalence of PA-HC and tumor size. For assessment of reliability of subtype diagnosis of PA-HC in AVS, we compared the post-operative outcomes in two different AVS criteria (lateralization index (LI)>4 and aldosterone to aldosterone ratio (A/A)>4) for localization. Post-operative cure was defined as the aldosterone to renin ratio (ARR) less than 200 (pg/ml per ng/dl/h) or more than 50% reduction of aldosterone levels were achieved after surgery

Results: Of 1141 patients who included in present study, PA-HC was identified in 309 (27%) patients. Prevalence of PA-HC was gradually increased according to the tumor size (< 10mm, 77 of 460 (17%); 10 to 20mm, 131 of 491 (27%); 20 to 30mm, 83 of 159 (52%); 30mm≤, 18 of 31 (58%)) (p<0.05). Of the patients with PA-HC, 127 patients underwent unilateral adrenalectomy and 45 patients could be assessed for the post-operative outcomes. Coincidence between two AVS criteria was seen in 39 patients (27 cases LI>4 and A/A>4, 12 cases LI≤4 and A/A≤4), while 6 showed discrepancy between two criteria (2 cases LI>4 and A/A≤4, 4 cases LI≤4 and A/A>4). Of total, post-operative cure was achieved in 38 of 45 cases (84%). In detail, post-operative cure was achieved in 26 of 27 (96%) patients with meeting both LI>4 and A/A>4, 6 of 6 (100%) with either LI>4 or A/A>4, and 6 of 12 (50%) with both LI≤4 and A/A≤4.

Conclusion: Prevalence of HC was considerably high in patients with PA, especially in a tumor greater than 20mm in size. Standard criteria, LI>4, for AVS could be used even in patients with PA-HC and criterion of A/A>4 could aid the diagnostic accuracy in patients with PA-HC.

 

Disclosure: MT: Investigator, ONO-Pharma. Nothing to Disclose: YS, HU, MN, IK, TY, TF