SCIENTIFIC BACKGROUND

ALAD, ALAS2, CPOX, FECH, HMBS, PPOX, UROD, UROS

Scientific Background

Porphyrias are caused by enzyme defects in heme biosynthesis, which lead to the accumulation and deposition of intermediate products in the tissue. Depending on the type of porphyria and exposure to noxious agents, abdominal, neurological and/or cutaneous symptoms occur.

 

Acute porphyrias:

The main symptom is abdominal colic, which is caused by alcohol, fasting or medication. The frequency for acute intermittent porphyria in Western Europe is 1:10,000.

 

Non-acute porphyrias:

Skin symptoms predominate, which are caused by cutaneous storage of heme precursors and lead to increased photosensitivity. Exposure to the sun leads to skin damage ranging from mild blistering to severe burns and mutilation.

 

Since clinical symptoms often do not allow a clear classification, differential diagnosis requires a metabolite profile from a urine sample that allows conclusions to be drawn about the type of porphyria. Genetic diagnostics can confirm the diagnosis and be used to verify carrier status.

 

References

All in: Adam MP, Ardinger HH, Pagon RA, et al., editors. GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2019: Wang B, Bissell DM. Hereditary Coproporphyria. 2012 Dec 13 [Updated 2018 Nov 8] / Balwani M, Bloomer J, Desnick R; Porphyrias Consortium of the NIH-Sponsored Rare Diseases Clinical Research Network. Erythropoietic Protoporphyria, Autosomal Recessive. 2012 Sep 27 [Updated 2017 Sep 7] / Liu LU, Phillips J, Bonkovsky H; Porphyrias Consortium

GENES

ALAD, ALAS2, CPOX, FECH, HMBS, PPOX, UROD, UROS

ASSOCIATED TESTS

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