Reliability of the porphobilinogen screening assay

Pathology. 1990 Oct;22(4):197-8. doi: 10.3109/00313029009086660.


A survey conducted by the Australian Association of Clinical Biochemists Porphyrin Working Party on urinary porphobilinogen screening showed good sensitivity (75-97.5%). This is contrary to reports in the literature and to our own observations. We therefore assessed a widely used screening method (Watson-Schwartz) and found poor sensitivity (40-69%), and even less sensitivity (28-53%) when the urine samples were normally coloured or concentrated. Thus the results obtained by the Working Party might mislead one to infer that the Watson-Schwartz method is reliable.

MeSH terms

  • Clinical Laboratory Techniques / methods
  • Humans
  • Porphobilinogen / urine*
  • Porphyrias / diagnosis*
  • Sensitivity and Specificity


  • Porphobilinogen