Pathology Handbook

Urinary Amino Acids

Clinical Indications

Urine amino acids are only indicated for investigation of sulphite oxidase deficiency, homocystinuria, renal transport defects including cystinuria and proximal renal tubular dysfunction. For other metabolic disorders,  plasma should be analysed.

Request Form 

Request on ICE


On request

Patient Preparation

Certain drugs (e.g. Ampicillin) may interfere with screening. Collect sample as close to acute event as possible. If non-acute situation, a morning sample is preferred. Avoid faecal or bacterial contamination.

Turnaround Time

2 weeks


Urine in white-top universal


5.0 ml


Urine bottle white top

Lab Handling

Sent to referral laboratory (Addenbrookes, Cambridge)


Samples should be transported to laboratory immediately.

Causes for Rejection

Unlabelled or incorrectly labelled sample; not meeting specific criteria for analysis; delay in sample reaching laboratory or in wrong sample container;
Urine pH >8


See laboratory report for interpretation of results