Diagnosing AHP
The earlier the diagnosis, the better
Early, accurate diagnosis of AHP may make a real difference in a person's quality of life by enabling them to:
- Take steps to manage factors that may trigger symptoms
- Understand what is happening in their bodies and why
- Avoid the complications that result from misdiagnoses and unnecessary surgeries
How AHP is diagnosed
People who may be experiencing symptoms and suspect AHP should ask their doctor to test for elevated PBG and ALA levels and porphyrins using simple (spot) urine tests. Below, you can see how doctors arrive at an AHP diagnosis. After the urine tests, genetic tests can be used to confirm the specific type of AHP.
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Rule out other conditions
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SUSPECT AHP SIGNS AND SYMPTOMS
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Test urine PBG, ALA, and Porphyrins
(Biochemical test for PBG, ALA, porphyrins)
- PBG (porphobilinogen)*
- ALA (aminolevulinic acid)*
- Porphyrins†
It is recommended to have a urine test within 48 hours of symptom onset since PBG and ALA levels drop over time, increasing the chance of a false negative result. Urine porphyrins is a nonspecific test and should not be used alone to diagnose AHP.
*PBG and ALA are substances that are produced when the liver makes heme. Increased levels of PBG and ALA can become toxic and have been associated with the symptoms and attacks of AHP.
†Porphyrin analyses may help identify the specific AHP.
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Review the test results
- Your doctor may perform genetic testing or porphyrin analyses to confirm the type of AHP.
- If you and your doctor still suspect AHP, repeat the urine test during an attack, and/or consider genetic testing.
Get information about no-charge genetic testing
that doctors can request through the Alnylam Act® program for patients meeting certain criteria.
If you suspect symptoms of AHP, it’s important to talk with your doctor. The Doctor Discussion Guide below will help you have a conversation about AHP.
I can still remember sitting in the doctor’s office when my test came back. He said that the results were positive—positive, not inconclusive!
— Megan, living with AHP
