Urine Porphobilinogen and Aminolevulinic Acid
Description:
Urine porphobilinogen (PBG) and 5-aminolevullinic acid (ALA) is a test profile offered by the SAS Porphyria Service in Reference Biochemisty at the Synnovis hub. This test is indicated in the diagnosis and monitoring of patients with acute porphyria. Quantitative measurement is by ion-exchange chromatography followed by spectrophotometry.
Clinical details:
ALA and PBG are precursors in the haem biosynthesis pathway and are significantly elevated in patients during an acute porphyria attack. Levels can remain elevated for weeks following an attack, or, in the case of acute intermittent porphyria (AIP), years. Moderate increases in ALA excretion can also be seen in patients with hereditary tyrosinaemia and lead toxicity. Urine PBG and ALA are analysed and reported together and reported as excretion per mmol of creatinine. Urgent PBG analysis is available during working hours (sample must arrive in lab by 3pm) and can be arranged by prior agreement with both the porphyria laboratory (contact details below) and the National Acute Porphyria Service (NAPS) on 029 2074 7747
Reference range:
PBG: 0.0 – 1.5 umol/mmol creatinine ALA: 0.0 – 3.8 umol/mmol creatinine
Synonyms or keywords:
ALA, PBG, porphobilinogen, aminolevullinic acid
Units:
umol/mmol creatinine
Department:
Location:
Sample type and Volume required:
10-20 mL fresh urine, preferably collected early morning. No preservative is necessary (plain universal)
Call in advance:
NO
Turnaround time:
Routine: 7-14 days Urgent PBG: Same day provided sample received by 3pm, otherwise next working day
Special sample instructions:
Protect from light
Storage and transport:
Store refrigerated. Send overnight at room temperature. Protect samples from light. If delay in dispatch, store and send frozen.
Contacts:
Porphyrin Laboratory at Blackfriars Hub
0208 078 8996
PorphyrinLab@synnovis.co.uk
Porphyrin Laboratory at Synnovis
Reference Chemistry, Floor One
Friars Bridge Court/ 41-43 Blackfriars Road/
London, SE1 8NZ
Reference Chemistry, Floor One
Friars Bridge Court/ 41-43 Blackfriars Road/
London, SE1 8NZ
Laboratory:
Last updated: 16/03/2026
