title: Dynamic testing with high-dose adrenocorticotrophic hormone does not improve lateralization of aldosterone oversecretion in primary aldosteronism patients.
abstract: OBJECTIVE
  Diagnosing aldosterone-producing adenoma (APA) involves a demonstration of the lateralization of aldosterone oversecretion because adrenal incidentalomas are common in hypertensive individuals and many small-sized APA escape identification with available imaging techniques. However, because of the pulsatile pattern of aldosterone secretion this can be a difficult undertaking. Stimulation of aldosterone secretion before adrenal vein sampling (AVS) can overcome this difficulty, but anecdotal data exist. We, therefore, prospectively investigated the usefulness of AVS with dynamic testing in primary aldosteronism (PA) patients.
  
  
  METHODS
  We enrolled 24 consecutive consenting patients with a biochemical diagnosis of PA from a tertiary referral centre to measure the effects of adrenocorticotrophic hormone (ACTH) on selectivity, the lateralization of aldosterone secretion to the APA side, and adverse effects. After correcting the hypokalemia we performed bilateral AVS. After 3 h supine resting, blood was simultaneously obtained from both sides. A high-dose ACTH (250 mug intravenous) bolus was then administered and AVS was repeated after 30 min.
  
  
  RESULTS
  AVS was bilaterally selective in 88% of patients; no adverse effects occurred. Of the 21 patients with bilaterally selective AVS, three had idiopathic hyperaldosteronism and 18 an APA that was surgically removed in 12 with an ensuing fall in blood pressure at follow-up. After ACTH patients showed a significant increase (P = 0.007) of aldosterone from contralateral adrenal vein blood, but not from the APA gland. Therefore, lateralization of aldosterone secretion on the APA side did not improve.
  
  
  CONCLUSIONS
  AVS is safe and accurate for identifying APA. However, at a statistical power of 99%, these results do not support the usefulness of high-dose ACTH testing to improve the diagnostic accuracy of AVS.
authors.affiliation: DMCS Internal Medicine 4 bInstitute of Radiology, Legnano, Italy. gianpaolo.rossi@unipd.it
authors.forename: Gian Paolo
authors.initials: GP
authors.lastname: Rossi
authors.forename: Chiara
authors.initials: C
authors.lastname: Ganzaroli
authors.forename: Diego
authors.initials: D
authors.lastname: Miotto
authors.forename: Renzo
authors.initials: R
authors.lastname: De Toni
authors.forename: Gaetana
authors.initials: G
authors.lastname: Palumbo
authors.forename: Gian Pietro
authors.initials: GP
authors.lastname: Feltrin
authors.forename: Franco
authors.initials: F
authors.lastname: Mantero
authors.forename: Achille C
authors.initials: AC
authors.lastname: Pessina
mesh_terms: D000236:Adenoma / Q000175:diagnosis / Q000378:metabolism; D000310:Adrenal Gland Neoplasms / Q000175:diagnosis / Q000378:metabolism; D000311:Adrenal Glands / Q000098:blood supply; D000324:Adrenocorticotropic Hormone / Q000494:pharmacology; D000328:Adult; D000368:Aged; D000450:Aldosterone / Q000378:metabolism*; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D006929:Hyperaldosteronism / Q000175:diagnosis*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies
chemical_list: D000450:Aldosterone; D000324:Adrenocorticotropic Hormone; D006854:Hydrocortisone