title: Biochemical differentiation of the porphyrias.
abstract: OBJECTIVE
  To differentiate the porphyrias by clinical and biochemical methods.
  
  
  METHODS
  We describe levels of blood, urine, and fecal porphyrins and their precursors in the porphyrias and present an algorithm for their biochemical differentiation. Diagnoses were established using clinical and biochemical data. Porphyrin analyses were performed by high performance liquid chromatography.
  
  
  CONCLUSIONS
  Plasma and urine porphyrin patterns were useful for diagnosis of porphyria cutanea tarda, but not the acute porphyrias. Erythropoietic protoporphyria was confirmed by erythrocyte protoporphyrin assay and erythrocyte fluorescence. Acute intermittent porphyria was diagnosed by increases in urine delta-aminolevulinic acid and porphobilinogen and confirmed by reduced erythrocyte porphobilinogen deaminase activity and normal or near-normal stool porphyrins. Variegate porphyria and hereditary coproporphyria were diagnosed by their characteristic stool porphyrin patterns. This appears to be the most convenient diagnostic approach until molecular abnormalities become more extensively defined and more widely available.
authors.affiliation: Division of Biochemistry, The Ottawa Hospital and the Department of Pathology and Laboratory Medicine, University of Ottawa, Ontario, Canada.
authors.forename: J T
authors.initials: JT
authors.lastname: Hindmarsh
authors.forename: L
authors.initials: L
authors.lastname: Oliveras
authors.forename: D C
authors.initials: DC
authors.lastname: Greenway
mesh_terms: D002851:Chromatography, High Pressure Liquid; D005243:Feces / Q000737:chemistry; D006801:Humans; D017119:Porphyria Cutanea Tarda / Q000097:blood / Q000652:urine; D017118:Porphyria, Acute Intermittent / Q000097:blood / Q000652:urine; D017121:Porphyria, Hepatoerythropoietic / Q000097:blood / Q000652:urine; D011164:Porphyrias / Q000097:blood* / Q000145:classification* / Q000652:urine; D017094:Porphyrias, Hepatic / Q000097:blood / Q000652:urine; D011166:Porphyrins / Q000032:analysis / Q000097:blood* / Q000652:urine
chemical_list: D011166:Porphyrins