title: Roles of clinical criteria, computed tomography scan, and adrenal vein sampling in differential diagnosis of primary aldosteronism subtypes.
abstract: BACKGROUND
  In patients with primary aldosteronism (PA), it is fundamental to distinguish between subtypes that benefit from different therapies. Computed tomography (CT) scans lack sensitivity and specificity and must be followed by adrenal venous sampling (AVS). Because AVS is not widely available, a list of clinical criteria that indicate the presence of an aldosterone-producing adenoma (APA) has been suggested.
  
  
  OBJECTIVE
  The objective of the study was to test the sensitivity and specificity of the last generation CT scans, test prospectively the usefulness of clinical criteria in the diagnosis of APA, and develop a flow chart to be used when AVS is not easily available.
  
  
  METHODS
  Hypertensive patients referred to our hypertension unit were included in our study.
  
  
  METHODS
  Seventy-one patients with confirmed PA participated in our study.
  
  
  METHODS
  All patients had a CT scan and underwent AVS.
  
  
  METHODS
  Final diagnosis of APA was the main measure.
  
  
  RESULTS
  A total of 44 and 56% of patients were diagnosed as having an APA and a bilateral adrenal hyperplasia (BAH), respectively. Twenty percent of patients with PA displayed hypokalemia. CT scans displayed a sensitivity of 0.87 and a specificity of 0.71. The posture test displayed a lower sensitivity and specificity (0.64 and 0.70, respectively). The distribution grades of hypertension were not significantly different between APA and BAH. Biochemical criteria of high probability of APA displayed a sensitivity of 0.32 and a specificity of 0.95.
  
  
  CONCLUSIONS
  This study underlines the central role of AVS in the subtype diagnosis of PA. The use of the clinical criteria to distinguish between APA and BAH did not display a satisfactory diagnostic power.
authors.affiliation: Department of Medicine and Experimental Oncology, University of Torino, 10126 Torino, Italy. paolo.mulatero@libero.it
authors.forename: Paolo
authors.initials: P
authors.lastname: Mulatero
authors.forename: Chiara
authors.initials: C
authors.lastname: Bertello
authors.forename: Denis
authors.initials: D
authors.lastname: Rossato
authors.forename: Giulio
authors.initials: G
authors.lastname: Mengozzi
authors.forename: Alberto
authors.initials: A
authors.lastname: Milan
authors.forename: Corrado
authors.initials: C
authors.lastname: Garrone
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Giraudo
authors.forename: Giorgio
authors.initials: G
authors.lastname: Passarino
authors.forename: Domenica
authors.initials: D
authors.lastname: Garabello
authors.forename: Andrea
authors.initials: A
authors.lastname: Verhovez
authors.forename: Franco
authors.initials: F
authors.lastname: Rabbia
authors.forename: Franco
authors.initials: F
authors.lastname: Veglio
mesh_terms: D000311:Adrenal Glands / Q000098:blood supply* / Q000473:pathology; D000328:Adult; D001800:Blood Specimen Collection / Q000379:methods; D003937:Diagnosis, Differential; D006801:Humans; D006929:Hyperaldosteronism / Q000145:classification / Q000175:diagnosis*; D006965:Hyperplasia; D008875:Middle Aged; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed; D014680:Veins