Aldosterone

Container: EDTA (Lavender top)

Sample type: Plasma

Test name: Aldosterone a.k.a. RAR

Condition / Indication: Conns Syndrome, unexplained hypertension.

Special precautions & notes: In the first instance renin is usually measured in conjunction with aldosterone.  Please contact laboratory to discuss patient preparation and drugs which may influence results. Send samples at room temperature (not on ice) to laboratory as soon as possible as samples need to be separated ideally within 1 hour. All drugs should be discontinued for 2 weeks before samples are collected. If a patient is on treatment with aldosterone antagonists (e.g. spironolactone) or oestrogens, the therapy must be discontinued for at least 6 weeks before the aldosterone-renin system is assessed. If the patient’s hypertension is such that all drug therapy cannot be withdrawn safely, the b-blocker, prazosin, has little effect on the aldosterone-renin system. b-blockers and diuretics have predictable effects but calcium channel blockers and ACE inhibitors must be avoided. Interpretation is particularly difficult when the patient is on a mixed-drug regime. The patient must be receiving an adequate intake of sodium (100-150 mmol/day) and potassium (50-100 mmol/day).

Reference range: Supine: 100 - 450 pmol/L. Erect: 100-800 pmol/L.

Container: EDTA (Lavender top)

Ideal volume (mL): 5 mL

Referred outside NBT for analysis? Yes

Discipline: Clinical Biochemistry

Turnaround time: 21 days

Referral location: Department of Clinical Biochemistry, King's College Hospital, Bessemer Wing, Denmark Hill, London, SE5 9RS