Table 2

The porphyrias: patterns of overproduction of haem precursors

DisorderPBG/ALAPorphyrins Faecal porphyrinsErythrocyte porphyrinsPlasma fluorescence emission peak
*Total porphyrins may be increased due to presence of excess uroporphyrin.6
†PBG and ALA excretion may be normal when only skin lesions are present.
‡Hexacarboxylix and pentacarboxylic porphyrins and coproporphyrin are increased to a smaller extent. Uroporphyrin is a mixture of type I and III isomers; heptacarboxylic porphyrin is mainly type III.
ALA, 5-aminolevulinate; PBG, porphobilinogen.
ALA dehydratase deficiencyALACopro IIINot increasedZn–proto
Acute intermittent porphyriaPBG > ALA(porphyrin mainly from PBG)Normal, or occasional slight increase in copro, proto*Not increased615–620 nm
Congenital erythropoietic porphyriaNot increasedUro I, Copro ICopro IZn–proto, proto615–620 nm
Copro I, Uro I
Porphyria cutanea tardaNot increasedUro, Hepta‡Isocopro, Hepta‡Not increased615–620 nm
Hereditary coproporphyriaPBG > ALA†Copro IIICopro IIINot increased615–620 nm
(porphyrin from PBG)
Variegate porphyriaPBG > ALA†Copro IIIProto IX > Copro III, X porphyrinNot increased624–627 nm
(porphyrin from PBG)
Erythropoietic protoporphyriaNot increasedNot increased± ProtoporphyrinProtoporphyrin626–634 nm