Test Entry - Detail

Citrate (Spot Urine)

General

Clinical Use:

Urinary citrate is a major inhibitor of kidney stone formation, partly due to calcium binding in urine. Low urine citrate levels are considered a risk factor for kidney stone formation. There are several metabolic disorders associated with low urinary citrate concentrations. Any condition which lowers renal tubular pH or intracellular pH, may decrease citrate, e.g. metabolic acidosis, increased acid ingestion, hypokalaemia or hypomagnesaemia.

Availability:

Samples are batched and tested once a week.
Spot urine citrate is not suitable for patients >=18Y.
If spot sample received on a patient >=18Y for urine citrate, please organise recollection of a 24 hour urine.

Code:

UCTCR

Handling Instructions (to laboratory):

If delay >30 minutes in delivery of sample to PathWest, sample must be collected at laboratory.

Hyperlink:

Reference Interval:

Age                        Citrate/Creat Ratio

Birth to < 3 years          > 0.30 mmol/mmol
    3 to < 18 years         > 0.10 mmol/mmol

Collection Requirements

Container:

Urine Container (URINE),

Sample Type:

See container

Minimum Collection Volume:

5mL

Collection Instructions:

Sample must be acidified to pH <3.6 within 30 minutes of collection using a small amount of sulphamic acid.
Note that for external collections, acidification of at least 5 mL of urine sample to pH <3.6 within 30 minutes of collection can be performed using a small volume of 6M HCl.

Processing Requirements

Alternate Containers:

Processing Instructions:

Sample must be acidified to pH <3.6 within 30 minutes of collection using a small amount of sulphamic acid.

Minimum Assay Volume:

5mL

Stability:

Transport Instructions (to testing laboratory):

Send sample chilled.

Testing Locations

Performed at:

Section	Department	Site	Contact Phone
Special Chemistry	Biochemistry	Fiona Stanley Hospital	6152 2830

Last Updated : 13-08-2025 13:11