Tests and diagnosisBy Mayo Clinic staff
Many signs and symptoms of porphyria are similar to those of other more common diseases. Also, because porphyria is rare, many doctors have not seen cases of the disorder before, making it more difficult to diagnosis. Because porphyria's signs and symptoms usually aren't distinctive, laboratory tests are required to make a definitive diagnosis of porphyria and to determine which form of the disease you have.
If your doctor suspects porphyria, he or she may recommend the following tests:
- Urine test. If you have a form of acute porphyria, a urine test may reveal elevated levels of two substances: porphobilinogen and delta-aminolevulinic acids, as well as other porphyrins.
- Blood test. If you have a form of cutaneous porphyria, a blood test may show an elevation in the level of porphyrins in your blood plasma.
- Stool sample test. Analysis of a stool sample may reveal elevated levels of some porphyrins that may not be detected in urine samples. This test may help your doctor determine your specific type of porphyria.
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