title: Unilateral adrenal hyperplasia: a novel cause of surgically correctable primary hyperaldosteronism.
abstract: BACKGROUND
  Primary hyperaldosteronism may be caused by an aldosterone-producing adenoma (APA), which is correctable by unilateral adrenalectomy or by idiopathic adrenal hyperplasia, a bilateral disease without any indication for surgery. This study sought to assess the prevalence and the results of surgery in unilateral adrenal hyperplasia (UAH).
  
  
  METHODS
  The study included 35 patients who underwent unilateral adrenalectomy because of primary hyperaldosteronism after unequivocal successful lateralization by adrenal venous sampling. Demographics, biochemical evaluation, and blood pressure were assessed pre- and postoperatively. Pathology was categorized as APA (isolated adenoma), nodular (multiple micromacronodules), and diffuse UAH (gland thickening without nodules).
  
  
  RESULTS
  Pathology revealed 9 APAs and 23 nodular and 3 diffuse UAHs. Patients with APAs and UAHs were statistically similar regarding demographics and preoperative blood pressure levels. Bilateral adrenal involvement was evident at imaging in 10 patients (11% in APA versus 35% in UAH, P = NS). After surgery, biochemical cure of the disease was achieved in all patients; blood pressure levels normalized in 66.6% of patients and ameliorated in 22.2% in APA versus 34.6% and 50% in patients with UAH (P = NS). At a long-term follow-up, only 1 patient with nodular UAH experienced a biochemical recurrence of disease.
  
  
  CONCLUSIONS
  UAH is not rare, sharing the same features of APA. When disease lateralization is confirmed by adrenal venous sampling, unilateral adrenalectomy achieves excellent long-term results.
authors.affiliation: Minimally Invasive Endocrine Surgery Unit, Department of Surgery, Oncology and Gastroenterology, University of Padua, Padua, Italy. maurizio.iacobone@unipd.it
authors.forename: Maurizio
authors.initials: M
authors.lastname: Iacobone
authors.forename: Marilisa
authors.initials: M
authors.lastname: Citton
authors.forename: Giovanni
authors.initials: G
authors.lastname: Viel
authors.forename: Riccardo
authors.initials: R
authors.lastname: Boetto
authors.forename: Italo
authors.initials: I
authors.lastname: Bonadio
authors.forename: Saveria
authors.initials: S
authors.lastname: Tropea
authors.forename: Franco
authors.initials: F
authors.lastname: Mantero
authors.forename: Gian Paolo
authors.initials: GP
authors.lastname: Rossi
authors.forename: Ambrogio
authors.initials: A
authors.lastname: Fassina
authors.forename: Donato
authors.initials: D
authors.lastname: Nitti
authors.forename: Gennaro
authors.initials: G
authors.lastname: Favia
mesh_terms: D000306:Adrenal Cortex Neoplasms / Q000150:complications / Q000175:diagnosis / Q000601:surgery; D000311:Adrenal Glands / Q000473:pathology*; D000315:Adrenalectomy; D018246:Adrenocortical Adenoma / Q000150:complications / Q000175:diagnosis / Q000601:surgery; D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D006929:Hyperaldosteronism / Q000175:diagnosis / Q000209:etiology* / Q000601:surgery*; D006965:Hyperplasia; D008297:Male; D008875:Middle Aged