Diagnosis of Acute Hepatic Porphyria

Medically Reviewed by Sabrina Felson, MD on May 18, 2023
3 min read

If you have acute hepatic porphyria (AHP), it’s important to get the right diagnosis early. Prompt care can help lessen your symptoms and keep more problems away.

Signs and symptoms of AHP are nonspecific: they are found in lots of other conditions. That makes it hard to get a fast diagnosis. But with the right tests, your doctor can find out if you have AHP.

Your doctor will give you a physical exam and ask about your health history. Then, they’ll run tests to make sure you don’t have another condition.

Some health issues with symptoms similar to those of AHP include:

  • Appendicitis
  • Cholecystitis
  • Endometriosis
  • Guillain-Barre syndrome
  • Lead poisoning
  • Stomach flu or gastroenteritis
  • Stomach ulcer
  • Colitis
  • Urinary tract infection

Don’t be afraid to ask your doctor about AHP. They may not think to test for it at first. It can take an average of 15 years to get a diagnosis. It’s a good idea to tell your health care provider about any repeat symptoms that show up together. That includes:

  • Really bad stomach pain
  • Nausea or throwing up
  • Muscle weakness
  • Mood changes, like anxiety and depression and even hallucinations

 

Your doctor will ask you to pee in a cup. Then they'll look for high levels of enzymes called:

  • Porphobilinogen (PBG)
  • Delta-aminolevulinic acid (ALA)

High PBG is always a sign you have AHP. If your pee has a reddish tint, your doctor may also test it for porphyrins, a natural chemical in your body that's involved in the creation of hemoglobin. But if you have high levels of that, it doesn't necessarily mean you have AHP. High levels of porphyrins show up in a lot of other medical conditions.

For best results, your doctor should test your pee within a few days of an acute attack.

Your doctor may take a stool sample. That can help them find out if you have AHP. That’s because porphyrins will stay in your poop for years after an attack. (You’ll need to poop in a cup. That’s because the sample shouldn’t have any urine or water on it.)

Your doctor may take blood from a vein in your arm. In some cases, AHP can lower levels of an enzyme called porphobilinogen deaminase (PBG-D) in your red blood cells. Porphyrins will also show up in your blood.

Special labs can run tests on your genes to find changes, or mutations, in your DNA. They’ll confirm your diagnosis of AHP. You may need to give the doctor a swab of saliva from inside your cheek. 

You don’t need genetic testing to find out if you have AHP. But it’s the best way to get a diagnosis if you don’t have symptoms right now or if you’ve never had an attack. The results can also let your family members know if they should get screened, too.

You can get a test for each kind of AHP. But your doctor may not know which one you have. In that case, you can get a “triple test.” That’ll screen for:  

  • AIP (HMBS gene)
  • HCP (CPOX gene)
  • VP (PPOX gene)

These tests can be costly and aren’t available everywhere. Talk with your doctor about which tests might be the best ones for you.