title: Systematic review: diagnostic procedures to differentiate unilateral from bilateral adrenal abnormality in primary aldosteronism.
abstract: BACKGROUND
  Computed tomography (CT), magnetic resonance imaging (MRI), and adrenal vein sampling (AVS) are used to distinguish unilateral from bilateral increased aldosterone secretion as a cause of primary aldosteronism. This distinction is crucial because unilateral primary aldosteronism can be treated surgically, whereas bilateral primary aldosteronism should be treated medically.
  
  
  OBJECTIVE
  To determine the proportion of patients with primary aldosteronism whose CT or MRI results with regard to unilateral or bilateral adrenal abnormality agreed or did not agree with those of AVS.
  
  
  METHODS
  PubMed, MEDLINE, EMBASE, and Cochrane Library, 1977 to April 2009.
  
  
  METHODS
  Studies describing adults with primary aldosteronism who underwent CT/MRI and AVS were included. Of 472 initially identified studies, 38 met the selection criteria; extractable data were available for 950 patients.
  
  
  METHODS
  The CT/MRI result was considered accurate when AVS showed unilaterally increased aldosterone secretion on the same side as the abnormality seen on CT/MRI or when AVS showed symmetric aldosterone secretion and CT/MRI revealed bilateral or no unilateral abnormality.
  
  
  RESULTS
  In 37.8% of patients (359 of 950), CT/MRI results did not agree with AVS results. If only CT/MRI results had been used to determine lateralization of an adrenal abnormality, inappropriate adrenalectomy would have occurred in 14.6% of patients (where AVS showed a bilateral problem), inappropriate exclusion from adrenalectomy would have occurred in 19.1% (where AVS showed unilateral secretion), and adrenalectomy on the wrong side would have occurred in 3.9% (where AVS showed aldosterone secretion on the opposite side).
  
  
  CONCLUSIONS
  The lack of follow-up data in the included articles made it impossible to confirm that adrenalectomies were performed appropriately.
  
  
  CONCLUSIONS
  When AVS is used as the criterion standard test for diagnosing laterality of aldosterone secretion in patients with primary aldosteronism, CT/MRI misdiagnosed the cause of primary aldosteronism in 37.8% of patients. Relying only on CT/MRI may lead to inappropriate treatment of patients with primary aldosteronism.
authors.affiliation: Radboud University Nijmegen Medical Centre, Nijmegen, the Netherlands.
authors.forename: Marlies J E
authors.initials: MJ
authors.lastname: Kempers
authors.forename: Jacques W M
authors.initials: JW
authors.lastname: Lenders
authors.forename: Lieke
authors.initials: L
authors.lastname: van Outheusden
authors.forename: Gert Jan
authors.initials: GJ
authors.lastname: van der Wilt
authors.forename: Leo J
authors.initials: LJ
authors.lastname: Schultze Kool
authors.forename: Ad R M M
authors.initials: AR
authors.lastname: Hermus
authors.forename: Jaap
authors.initials: J
authors.lastname: Deinum
mesh_terms: D000311:Adrenal Glands / Q000098:blood supply; D000450:Aldosterone / Q000097:blood / Q000378:metabolism*; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D006929:Hyperaldosteronism / Q000175:diagnosis* / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008297:Male; D012083:Renin / Q000097:blood; D012965:Sodium Chloride; D014057:Tomography, X-Ray Computed; D014680:Veins
chemical_list: D012965:Sodium Chloride; D000450:Aldosterone; D012083:Renin