Porphyrias

  • Diagnosis
  • Algorithms
  • Monitoring
  • Background
  • Lab Tests
  • References
  • Related Topics

Indications for Testing

  • Patient with abdominal symptoms and/or cutaneous symptoms compatible with porphyria

Laboratory Testing

  • NOTE – porphyrin test results are complex and require interpretation by a medical expert

Differential Diagnosis

  • Acute porphyrias – use urine porphobilinogen (PBG) to assess metabolic response to IV hematin
  • Porphyria cutanea tarda (PCT) – use urine porphyrins or porphyrins, total, plasma or serum, for monitoring

Porphyrias are a group of inherited or acquired enzyme disorders of the heme biosynthetic pathway that result in overproduction of porphyrins or porphyrin precursor compounds. These are rare disorders. All forms of porphyria together afflict fewer than 200,000 people in the U.S.

Pathophysiology

  • Heterogenous group of inherited or acquired disorders of heme biosynthesis
    • Partial deficiency of one of seven enzymes in the pathway causes the clinical features of porphyria
    • Defined by accumulation and excretion of heme precursors specific for the individual disease

Clinical Presentation

Tests generally appear in the order most useful for common clinical situations. Click on number for test-specific information in the ARUP Laboratory Test Directory.

Porphobilinogen (PBG), Urine 0080260
Method: Quantitative Ion Exchange Chromatography/Spectrophotometry

Limitations 

24-hour specimen is more sensitive

Follow-up 

If result is negative but high clinical suspicion exists, repeat when symptoms are present

Porphyrins, Fecal 0099824
Method: Quantitative High Performance Liquid Chromatography

Limitations 

Bacterial modification of fecal porphyrins is extensive

Meat in diet may influence test results

Porphyrins, Total, Plasma or Serum 0080429
Method: Quantitative Fluorometry

Limitations 

Does not identify specific porphyrin

Porphyrins and Porphobilinogen (PBG), Urine 2002181
Method: High Performance Liquid Chromatography/Ion Exchange Chromatography/Quantitative Spectrophotometry

Limitations 

24-hour specimen is more sensitive

Porphyrins, Fractionation and Quantitation, Urine 2002058
Method: Quantitative High Performance Liquid Chromatography

Limitations 

24-hour specimen is more sensitive

Urine coproporphyrin is elevated in many common disorders

Follow-up 

If test is negative but high clinical suspicion still exists, repeat when symptoms are present 

Erythrocyte Porphyrin (EP), Whole Blood 0020610
Method: Fluorometry

Limitations 

Also elevated in early and late iron deficiency, anemia of chronic disease, and chronic lead poisoning

Follow-up 

If lead poisoning suspected, order whole blood lead testing

Aminolevulinic Acid (ALA), Urine 0080103
Method: Quantitative Ion Exchange Chromatography/Spectrophotometry

Limitations 

24-hour specimen is more sensitive

Follow-up 

If lead poisoning suspected, order whole blood lead testing

Porphobilinogen (PBG) Deaminase, Erythrocyte 0099550
Method: Quantitative Enzymatic/Fluorometry

Limitations 

Not recommended for diagnosis of an individual patient

Best performed in association with a specimen from an unaffected family member

Aminolevulinic Acid Dehydratase (ALAD), Blood 2011012
Method: Quantitative Enzymatic/Spectrofluorometry

Cutaneous Direct Immunofluorescence, Biopsy 0092572
Method: Direct Immunofluorescence

Limitations 

Characteristic pattern of staining but not specific

Epithelial Skin Antibody 0090299
Method: Indirect Immunofluorescence
(Indirect Fluorescent Antibody)

Limitations 

Negative in porphyria and pseudoporphyria; positive in immunobullous diseases

Guidelines

Anderson KE, Bloomer JR, Bonkovsky HL, Kushner JP, Pierach CA, Pimstone NR, Desnick RJ. Recommendations for the diagnosis and treatment of the acute porphyrias. Ann Intern Med. 2005; 142(6): 439-50. PubMed

Laboratory Diagnosis - Acute Porphyrias. European Porphyria Network. [Accessed: Nov 2015]

General References

Aarsand AK, Boman H, Sandberg S. Familial and sporadic porphyria cutanea tarda: characterization and diagnostic strategies. Clin Chem. 2009; 55(4): 795-803. PubMed

American Porphyria Foundation. Houston, TX [Accessed: Apr 2015]

Balwani M, Desnick RJ. The porphyrias: advances in diagnosis and treatment. Blood. 2012; 120(23): 4496-504. PubMed

Balwani M, Doheny D, Bishop DF, Nazarenko I, Yasuda M, Dailey HA, Anderson KE, Bissell M, Bloomer J, Bonkovsky HL, Phillips JD, Liu L, Desnick RJ, Porphyrias Consortium of the National Institutes of Health Rare Diseases Clinical Research Network. Loss-of-function ferrochelatase and gain-of-function erythroid-specific 5-aminolevulinate synthase mutations causing erythropoietic protoporphyria and x-linked protoporphyria in North American patients reveal novel mutations and a high prevalence of X-linked protoporphyria. Mol Med. 2013; 19: 26-35. PubMed

Frank J, Poblete-Gutiérrez P. Porphyria cutanea tarda--when skin meets liver. Best Pract Res Clin Gastroenterol. 2010; 24(5): 735-45. PubMed

Maynard B, Peters MS. Histologic and immunofluorescence study of cutaneous porphyrias. J Cutan Pathol. 1992; 19(1): 40-7. PubMed

Parnas M, Frank E. Clinical Laboratory News: Porphyrias. American Association for Clinical Chemistry. [Accessed: Apr 2015]

Puy H, Gouya L, Deybach J. Porphyrias. Lancet. 2010; 375(9718): 924-37. PubMed

Sarkany RP E. Making sense of the porphyrias. Photodermatol Photoimmunol Photomed. 2008; 24(2): 102-8. PubMed

The Porphyrias Consortium. Rare Diseases Clinical Research Network. New York, NY [Accessed: ]

Ventura P, Cappellini MDomenica, Rocchi E. The acute porphyrias: a diagnostic and therapeutic challenge in internal and emergency medicine. Intern Emerg Med. 2009; 4(4): 297-308. PubMed

Medical Reviewers

Last Update: August 2016