RT Journal Article SR Electronic T1 ACP Best Practice No 165 JF Journal of Clinical Pathology JO J Clin Pathol FD BMJ Publishing Group Ltd and Association of Clinical Pathologists SP 500 OP 507 DO 10.1136/jcp.54.7.500 VO 54 IS 7 A1 A C Deacon A1 G H Elder YR 2001 UL http://jcp.bmj.com/content/54/7/500.abstract AB The porphyrias are uncommon disorders of haem biosynthesis and their effective management requires prompt and accurate diagnosis. This article describes methods for the determination of urinary porphobilinogen, urinary and faecal total porphyrins, and total porphyrins in erythrocytes and plasma that are suitable for use in non-specialist laboratories. The selection and interpretation of these methods, and the indications for further, more specialised, investigation are discussed.