Turnaround times
The quoted turnaround time is from sample receipt in the laboratory, to results authorisation in the Laboratory Information Management system. The times do not include transport of specimen to the laboratory or the administrative process to print and post/email reports. Service users must allow for transport and reporting time when ordering tests.
Clinical background:
Used in the investigation of acute unexplained abdominal pain or neurological symptoms where a undetectable concentration of total urine porphyrin (TUP) would exclude an acute porphyria as the cause.
Specimen container paediatric:
Urine (Random sample)
Specimen container adult:
Urine (Random sample)
Minimum volume paediatric:
2 mL
Minimum volume adult:
2 mL
Special requirements:
Protect from light. Send to the laboratory immediately.
Sample stability:
If protected from light, samples are stable for 2 days at 2 to 8°C or 1 month at -20°C.
Interpretation:
Light results in degradation of the porphyrins which will produce a falsely low result.
Reference ranges:
TUP/creatinine ratio < 35 nmol/mmol
Factors affecting result:
Light causes degradation of porphyrins