Unfortunately, due to an analyser fault at the referral laboratory, testing for trimethylamine is currently suspended. If possible, we recommend delaying sample collection until approximately the end of May 2026, when hopefully the service will resume. Samples received before then will be frozen and not sent for analysis until the service is running again.
Trimethylamine is an organic compound with a strong ‘’fishy’’ odour in low concentrations. For the diagnosis of primary and secondary trimethylaminuria (Fish Odour Syndrome).
Tube
08 (UR) – Urine 24 Hr Chemical Preservative. (Hydrocholric acid preservative required)
ID
Tests&Tubes0249
Additional Information
TMAU is associated with ingestion of certain foods and so it is important to collect this sample at the time of the odour. A dietary ‘choline load’ is recommended before collecting the samples by using foods known to produce the odour e.g. beans, eggs, liver. Please contact the duty biochemist if for more information if required.
Turn Around
Please note, the service is currently suspended and will hopefully resume in May 2026. Usual turnaround time is 6 to 8 weeks.
Send to
CfLM, St James University Hospital
(Test referred to: Sheffield Children’s Hospital)
Contact
For further details please contact Leeds Pathology customer services: [email protected].
Advice
Full information on all referred tests can be found on the referred tests information database, EQMS reference BSF2REC17003.
Collection Con
Ideally, 24h collection collected into 10 mL 6M HCl. Can send 20 mL plain urine in a Universal which can be acidified in the Blood Sciences lab. Instructions to lab: contact Duty Biochemist if sample requires acidification to pH < 2. Send 20 mL. Store sample frozen at -80C
Minimum volume: 10 mL urine
Sample REQ
Urine
Ref. Range Notes
Free TMA/ creat ratio: < 7.7 µmol/mmol crt
TMA-N-Oxide / creat ratio: < 119 µmol/mmol crt
% N-Oxidation: > 94%
Additional interpretation will be provided on the report.