Porphyrins are oxidised intermediate metabolites of haem biosynthesis. They are readily excreted in excess when they accumulate as a result of the inhibition of specific enzymes in the haem biosynthetic pathway. Haem is required for oxygen binding, transport and utilisation as well as cytochromes and electron transfer in the mitochondria. Disorders in haem production have been associated with genetic disorders, metabolic conditions, nutritional status, oxidative stress and exposure to chemicals or metals. Various drugs and other substances can also suppress enzymes involved in porphyrin metabolism. These include alcohol, sedatives, analgesics, antibiotics, oestrogens, oral contraceptive pill, anaemia, pregnancy and liver disease.
The high rate of haeme production facilitates the use of urinary porphyrins as early and sensitive biomarkers of haeme production disorders. Specific urinary porphyrin profiles have specifically been associated with very high levels of toxic metals such as mercury, lead and arsenic. Various drugs and other substances can suppress enzymes involved in porphyrin metabolism and affect overall levels. Such compounds include alcohol, sedatives, analgesics, antibiotics, oestrogen and oral contraceptives. Anaemia, pregnancy and liver disease can all affect porphyrin metabolism.
When should I use
This test is indicated for anaemias, autism, genetic disorders, nutritional deficiencies, oxidative stress, metabolic disturbances and toxic chemical or metal exposure.