Purpose of the test
The renin-angiotensin-aldosterone axis plays a vital role in sodium homeostasis and maintenance of blood volume and pressure. Disorders of the renin-angiotensin-aldosterone axis can lead to major metabolic imbalances and disease.
Renin, aldosterone and their ratio are the most frequently measured parameters used to assess renin-angiotensin-aldosterone axis integrity.
Assessment of the renin-angiotensin-aldosterone axis has assumed a much greater role in clinical practice, particularly in the evaluation of patients with hypertension.
In addition, the axis is often evaluated in patients with:
- Hypo or hyperkalaemia who may have hyperaldosteronism (or other forms of genuine or apparent mineralocorticoid excess) or hypoaldosteronism respectively.
- Adrenal insufficiency - to distinguish primary from secondary cause.
Renin (µ/L): Upright 5.4 - 60 Supine 5.4 - 30
Aldosterone (pmol/L): Upright 100 - 800, Supine 100 - 450
Aldo/Renin ratio: <80: Conn’s unlikely. >/=200: Conn’s likely. 80-200: Conn’s not excluded
EDTA Plasma - Process blood samples at room temperature in a non-chilled centrifuge. Plasma should be separated from cells immediately after centrifugation, aliquoted into two 2mL pots (min 500µL in each), and frozen at –20ºC.
Storage and Transport
Plasma can be transported on dry ice by courier . A minimum volume of 500 µl required in each 2mL pot.
Address specimens to: Department of Clinical Biochemistry, Bessemer Wing, King’s College Hospital, Denmark Hill, London SE5 9RS
Results within 7-10 working days
Price available on application - please contact email@example.com. Discounts could be available for significant workloads.
Dr Roy Sherwood
T 020 3299 3726
Ms Rachel Langworthy
T 020 3299 4130
Funder JW, Carey RM et al. (2008) Clinical Practice Guideline: Case Detection, Diagnosis, and treatment of Patients with Primary Aldosteronism: An Endocrine Society Clinical Practice Guideline. J Clin Endocrin Metab. 93(9): 3266-3281