Porphyria

Last updated: Saturday, 07, August, 2010
Key InformationAppropriate Tests

Consult pathologist regarding appropriate specimens.

If patient has intermittent symptoms, specimens for porphyrin analysis should be collected during a symptomatic period. Skin biopsy of lesions may suggest porphyria and can exclude other causes of bullous and scarring lesions. Specific porphyrin disorders may have the following manifestations:

(a) acute neurological porphyrias - abdominal pain, constipation, hypertension, neuropathy, psychiatric symptoms;

(s) photosensitive skin fragility with scarring;

(u) solar urticaria - pruritus, erythema and swelling with ultimate scarring.

Coproporphyrinuria may occur in cholestasis, and poisoning with heavy metals (eg, lead, mercury)  or certain chemicals (eg, hexachlorbenzene).

Porphyria cutanea tarda (s) 

Porphyrins - urine. Porphyrins - faeces only occasionally required.Uroporphyrinogen decarboxylase - red cells, if hereditary form suspected.

Protoporphyria (u) 

Porphyrins - red cell.

Acute intermittent porphyria (a)

Porphobilinogen - urine, porphyrins - urine. Porphobilinogen deaminase - red cell, for confirmation of diagnosis and in asymptomatic family members.

Porphyria variegata (s,a) 

Porphyrins - urine, porphobilinogen - urine; porphyrins - faeces.

Hereditary coproporphyria (s,a) 

Porphyrins - urine, porphobilinogen - urine; porphyrins - faeces.

Congenital erythropoietic porphyria (s) 

Porphyrins - urine and porphyrins - red cell.

Plumboporphyria (a) 

5-aminolaevulinate - urine.

Porphobilinogen synthetase - red cell. Lead - blood, to exclude lead toxicity as the cause.