Chemistry, toxicology & urinalysis
Organ specific
Adrenal
Saline suppression test
Author: Renu Virk, M.D.
Last author update: 1 February 2010
Last staff update: 9 April 2020
Copyright: 2002-2024, PathologyOutlines.com, Inc.
PubMed Search: Saline suppression [title]
Cite this page: Virk R. Saline suppression test. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/adrenalsalinesuppression.html. Accessed April 20th, 2024.
Definition / general
Indication:
Methodology:
- To confirm the diagnosis of primary aldosteronism (J Clin Endocrinol Metab 2006;91:2618)
- Other tests recommended for screening or confirmation are captopril suppression test and fludrocortisone suppression (Horm Metab Res 2010;42:406)
Methodology:
- Infuse 2L of 0.9% saline over 4 hours ("saline infusion test") OR give oral NaCl tablets 10 - 12 gm daily for 3 days ("oral sodium loading test")
- Blood levels: plasma aldosterone greater than 5 ng/dl (140 pmol/L) confirms the diagnosis of primary hyperaldosteronism
- Urine levels: collect 24 hour urine for aldosterone, creatinine (to assess the adequacy of urine collection), and sodium (to ensure adequate intake) on the last day of sodium chloride administration
- Aldosterone levels > 10 μg/24 hours (28 nmol/24 hours) confirms the diagnosis
Clinical features
- More difficult to perform than captopril suppression test, with comparable accuracy in patients with high sodium intake (Hypertension 2007;50:424)
