Screening and Confirmatory Tests for Porphyrias
Testing | In Patients With Acute Neurovisceral Symptoms | In Patients With Photosensitivity |
|---|---|---|
Screening | Urinary ALA, PBG, creatinine (random urine sample)* | Plasma porphyrins† |
Confirmation (when screening test results are significantly abnormal) | Urinary ALA, PBG, and creatinine (quantitative test)* Fecal and urinary porphyrins‡ Red blood cell PBG deaminase Plasma porphyrins† Genetic testing | Red blood cell porphyrins (total and metal-free) Urinary ALA, PBG, porphyrins, and creatinine (quantitative)* Fecal porphyrins‡ Plasma porphyrins† Genetic testing |
* Results are corrected according to urine creatinine level. | ||
† The preferred method is by direct fluorescent spectrophotometry. | ||
‡ Urinary and fecal porphyrins are fractionated only if the total is increased. | ||
Data from Wang B, Bonkovsky HL, Lim JK, Balwani M. AGA Clinical Practice Update on Diagnosis and Management of Acute Hepatic Porphyrias: Expert Review. Gastroenterology 2023;164(3):484-491. doi:10.1053/j.gastro.2022.11.034 | ||
ALA = delta-aminolevulinic acid; PBG = porphobilinogen. | ||