Porphyrins help form many important substances in the body. One of these is hemoglobin. This is the protein in red blood cells that carries oxygen in the blood.
What are porphyrias?
The porphyrias are a group of diseases associated with hereditary and acquired deficiencies in the biosynthetic pathway of heme. The laboratory diagnosis of porphyrin disorders rests primarily with the identification of patterns of porphyrin intermediates. Multiple species have been identified for each of the porphyrins based on the order of their substitutions. Porphyrias are disorders of porphyrin metabolism caused by specific defects of enzymes of the heme biosynthetic pathway. Consequently, each type of porphyria is characterized by the accumulation of the precursor proximal to the step dependent on the defective enzyme.
All but two porphyrias (acute intermittent and plumbo-porphyria) are characterized by cutaneous lesions caused by the photosensitizing effects of accumulated porphyrins. Maximal skin reactivity occurs in the 400-410 nm region of the spectrum, known as the Soret band, which corresponds to the wavelengths that porphyrins show the most intense absorption. This assay allows differentiation of three conditions according to their porphyrin content.
- Variegate porphyria, (VP) is an autosomal dominant disorder associated by a defect in the enzyme protoporphyrinogen oxidase, which catalyzes the last step of heme biosynthesis. These cases present a peak in the spectral area of 626-628 nm.
- Erythropoietic protoporphyria (EPP) is another autosomal dominant condition that causes acute photosensitivity and is characterized by an increase of plasma protoporphyrin with a characteristic peal at 636 nm.
A third group which includes normal subjects, non-porphyria patients, and those suffering from acute intermittent porphyria, hereditary coproporphyria, congenital erythropoietic porphyria (Gunther Disease) and porphyria cutaneous porphyria cutanea tarda.
Function of this test:
a) To monitor porphyria cutanea tarda (PCT)
Porphyria cutanea tarda (PCT) is a rare disorder characterized by painful, blistering skin lesions that develop on sun-exposed skin (photosensitivity). Affected skin is fragile and may peel or blister after minor trauma. Liver abnormalities may also occur.
b) To confirm diagnosis of suspected variegate porphyria (VP)
Variegate porphyria (VP) is classified as both a cutaneous and an acute porphyria. It can present with chronic blistering cutaneous manifestations and/or acute attacks of neurovisceral manifestations that may become chronic.
c) To comfirm erythropoietic protoporphyria (EPP)
Erythropoietic protoporphyria (EPP) is an inherited porphyria resulting in the accumulation of protoporphyrins in red blood cells that causes acute, painful photosensitivity and potential liver disease. It typically presents in early childhood with immediate pain and crying upon exposure to bright sunlight.
References:
Shah A, Bhatt H. Cutanea Tarda Porphyria. [Updated 2023 Apr 17]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK563209/
Singal AK, Anderson KE. Variegate Porphyria. 2013 Feb 14 [Updated 2019 Dec 12]. In: Adam MP, Mirzaa GM, Pagon RA, et al., editors. GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2023. Available from: https://www.ncbi.nlm.nih.gov/books/NBK121283/
Ahmed jan N, Masood S. Erythropoietic Protoporphyria. [Updated 2023 Feb 16]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK563141/
Porphyrins, Total Serum
Every lab result you’ve ever had, charted and explained.
Healthmatters is a tracker for your lab results. Upload a report from any lab, any country — every marker charted and explained.
Start with my report →
All our content is backed by peer-reviewed studies, academic research, and trusted medical sources. We’re committed to accuracy and transparency — see our editorial policy for details.