title: Reassessment of the cosyntropin stimulation test in the confirmatory diagnosis and subtype classification of primary aldosteronism.
abstract: OBJECTIVE
  Although corticotropin is a representative secretagogue of aldosterone, the utility of the cosyntropin stimulation test (C-ST) in diagnosing primary aldosteronism (PA) has not been elucidated. Aim of the study was to evaluate the clinical utility of C-ST for confirmatory testing and subtype classification of PA.
  
  
  METHODS
  In this retrospective study, we identified patients with hypertension and positive case-detection results for PA who underwent C-ST and saline infusion testing (SIT) between 2006 and 2013 at eight referral centres in Japan. PA and essential hypertension (EH) were distinguished based on SIT results. PA subtype classification was determined by adrenal venous sampling (AVS). Plasma aldosterone concentration (PAC) was measured before and 30 and 60 min after intravenous cosyntropin administration. The ability of C-ST to distinguish PA from EH and to distinguish unilateral from bilateral disease was assessed by the area under the receiver operating characteristic curve.
  
  
  RESULTS
  Of 205 patients with hypertension and positive case-detection results, 139 (68%) had PA based on SIT results. Eighteen patients in whom AVS was unsuccessful were excluded from analysis. The baseline PAC before C-ST was significantly higher (P < 0·01) in patients with PA than in those with EH. However, the degree of difference in PAC between patients with PA and EH was not enhanced by the administration of cosyntropin. In addition, the administration of cosyntropin did not improve the distinction between bilateral and unilateral PA subtypes.
  
  
  CONCLUSIONS
  C-ST has no utility as a confirmatory and subtype testing of PA when the diagnosis of PA is based on the positive results in SIT.
authors.affiliation: Department of Endocrinology, Metabolism, and Hypertension, Clinical Research Institute, National Hospital Organization Kyoto Medical Center, Kyoto, Japan.
authors.forename: Hironobu
authors.initials: H
authors.lastname: Umakoshi
authors.affiliation: Department of Endocrinology, Metabolism, and Hypertension, Clinical Research Institute, National Hospital Organization Kyoto Medical Center, Kyoto, Japan.
authors.forename: Yang
authors.initials: Y
authors.lastname: Xiaomei
authors.affiliation: Department of Diabetes and Endocrinology, Saiseikai Yokohama City Toubu Hospital, Yokohama, Japan.
authors.forename: Takamasa
authors.initials: T
authors.lastname: Ichijo
authors.affiliation: Department of Cardiology, Akashi Medical Center, Akashi, Japan.
authors.forename: Kohei
authors.initials: K
authors.lastname: Kamemura
authors.affiliation: Department of Cardiology, Sanda City Hospital, Sanda, Japan.
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Matsuda
authors.affiliation: Department of Cardiology, Hiroshima General Hospital of West Japan Railway Company, Hiroshima, Japan.
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Fujii
authors.affiliation: Department of Cardiology, Saiseikai Tondabayashi Hospital, Tondabayashi, Japan.
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Kai
authors.affiliation: Department of Internal Medicine, Matsuyama Red Cross Hospital, Matsuyama, Japan.
authors.forename: Tomikazu
authors.initials: T
authors.lastname: Fukuoka
authors.affiliation: Department of Metabolism and Endocrinology, Clinical Research Institute, National Hospital Organization Kyushu Medical Center, Fukuoka, Japan.
authors.forename: Ryuichi
authors.initials: R
authors.lastname: Sakamoto
authors.affiliation: Department of Metabolism and Endocrinology, Clinical Research Institute, National Hospital Organization Kyushu Medical Center, Fukuoka, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Ogo
authors.affiliation: Department of Public Health, Kitasato University School of Medicine, Tokyo, Japan.
authors.forename: Tomoko
authors.initials: T
authors.lastname: Suzuki
authors.affiliation: Department of Endocrinology, Metabolism, and Hypertension, Clinical Research Institute, National Hospital Organization Kyoto Medical Center, Kyoto, Japan.
authors.forename: Tatsuki
authors.initials: T
authors.lastname: Ogasawara
authors.affiliation: Department of Endocrinology, Metabolism, and Hypertension, Clinical Research Institute, National Hospital Organization Kyoto Medical Center, Kyoto, Japan.
authors.forename: Mika
authors.initials: M
authors.lastname: Tsuiki
authors.affiliation: Department of Endocrinology, Metabolism, and Hypertension, Clinical Research Institute, National Hospital Organization Kyoto Medical Center, Kyoto, Japan.
authors.forename: Mitsuhide
authors.initials: M
authors.lastname: Naruse
mesh_terms: D000328:Adult; D000368:Aged; D003366:Cosyntropin / Q000494:pharmacology*; D003937:Diagnosis, Differential; D003940:Diagnostic Techniques, Endocrine / Q000592:standards*; D000075222:Essential Hypertension; D005260:Female; D006801:Humans; D006929:Hyperaldosteronism / Q000145:classification / Q000175:diagnosis*; D006973:Hypertension; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012372:ROC Curve; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D012965:Sodium Chloride / Q000008:administration & dosage
chemical_list: D003366:Cosyntropin; D012965:Sodium Chloride