NP-59 test for preoperative localization of primary hyperaldosteronism

Langenbecks Arch Surg. 2017 Mar;402(2):303-308. doi: 10.1007/s00423-017-1561-1. Epub 2017 Feb 21.


Purpose: Adrenal venous sampling is generally considered the gold standard to identify unilateral hormone production in cases of primary hyperaldosteronism. The aim of this study is to evaluate whether the iodine-131-6-β-iodomethyl-19-norcholesterol (NP-59) test may represent an alternative in selected cases.

Methods: Patients submitted to laparoscopic adrenalectomy for suspected primary hyperaldosteronism (n = 27) were retrospectively reviewed. When nuclear medicine tests were preoperatively performed, their results were compared with the histopathologic findings and clinical improvement.

Results: Nuclear medicine tests were realized in 13 patients. In 11 (84.6%), a planar anterior and posterior NP-59 scintigraphy was performed and a SPECT/TC in two (15.4%). Scintigraphy indicated a preoperative lateralization in 12 out of 13 patients (92.3%). When the value of NP-59 tests was based on pathologic results, it showed a sensitivity of 90.9% and a positive predictive value of 83.3%. When the nuclear medicine test's performance was based on postoperative blood pressure control, both sensitivity and positive predictive value were 91.6%.

Conclusions: Nuclear medicine tests represent a useful tool in the preoperative localisation of primary hyperaldosteronism with a high sensitivity and positive predictive value. In patients with contraindications to adrenal venous sampling like contrast allergies, or when it is inconclusive, scintigraphy can represent a useful and non-invasive alternative.

Keywords: Adrenal adenoma; NP-59 SPECT/TC; NP-59 scintigraphy; Primary hyperaldosteronism.

MeSH terms

  • Adosterol*
  • Adrenalectomy
  • Adult
  • Aged
  • Female
  • Humans
  • Hyperaldosteronism / diagnostic imaging*
  • Hyperaldosteronism / surgery
  • Laparoscopy
  • Magnetic Resonance Imaging
  • Male
  • Middle Aged
  • Predictive Value of Tests
  • Preoperative Care
  • Retrospective Studies
  • Single Photon Emission Computed Tomography Computed Tomography*


  • Adosterol