Porphyria | Main symptom | Test | Deficient enzyme | Heredity and penetrance | Number of patients in Finland (per 5.5 million inhabitants) |
---|---|---|---|---|---|
Acute intermittent porphyria (AIP) | Acute attack | Urinary PBG Urinary ALA Plasma porphyrins Eryhtrocyte PBGD AIP DNA test | PBGD | Autosomal dominantApprox. 20-50% of all mutation carriers develop symptoms during their lifetime. | Approx. 200 |
Variegate porphyria (VP) | Photosensitivity: fragility, blistering and scarring of the skin Acute attack | Plasma porfyrins Faecal porphyrins Urinary PBG Urinary ALA VP DNA test | PPOX | Autosomal dominant Approx. 30-40 % of all mutation carriers develop symptoms during their lifetime. | Approx. 150 |
Hereditary coproporphyria (HCP) | Photosensitivity: fragility, blistering and scarring of the skin Acute attack | Plasma porphyrins Nocturnal urinary porphyrins Faecal porphyrins Urinary PBG Urinary ALA HCP DNA test | CPOX | Autosomal dominant | 2 |
Porphyria cutanea tarda (PCT) | Photosensitivity: blistering and scarring of the skin Hepatopathy | Nocturnal urinary porphyrins Plasma porphyrins Erythrocyte UROD PCT DNA test | UROD | Autosomal dominant or acquired (symptoms triggered by other than genetic factors) | Approx. 100 |
Erythropoietic protoporphyria (EPP) | Photosensitivity: painful swelling and erythema of the skin Microcytic anaemia and acute liver failure | Blood porphyrins Plasma porphyrins Ratio of zinc-chelated to free protoporphyrin Lymphocyte FECH EPP DNA test | FECH | Autosomal recessive or dominant, in which case the phenotype depends on the polymorphisms of the normal allele Approx. 50% of all mutation carriers develop symptoms. | Approx. 50 |
X-linked protoporphyria (XLP) | Photosensitivity: painful swelling and redness of the skin Microcytic anaemia and acute liver failure | Blood porphyrins Plasma porphyrins Ratio of zinc-chelated to free protoporphyrin XLP DNA test | Increased production of ALAS2 | Linked to X chromosome, males symptomatic and females have symptoms due to inactivation of normal X chromosome | So far, no diagnosis has been made in Finland. About 10% of protoporphyrias of ALAS2 origin |
PBG = urinary porphobilinogen ALA = aminolevulinic acid PBGD = porphobilinogen deaminase PPOX = protoporphyrinogen oxidase CPOX = coproporphyrinogen oxidase UROD = uroporphyrinogen decarboxylase FECH = ferrochelatase ALAS2 = 5'-aminolevulinate synthase 2 |