Porphyrin Tests

Porphyrin tests measure the level of porphyrins in your blood, urine (pee), or stool (poop). Your body uses porphyrins to make heme. Heme is part of hemoglobin, which is a protein in your red blood cells that carries oxygen from your lungs to the rest of your body.

It's normal to have a small amount of porphyrins in your blood and other body fluids. But too much porphyrin may mean you have a type of porphyria. Porphyrias are a group of diseases that happen if you lack one of the proteins necessary to change porphyrins into heme.

If your body doesn't use porphyrins correctly, they can build up and cause illness. Porphyrias are very uncommon disorders that are usually inherited. That means these diseases tend to run in families because of a change in a gene that's passed down from parents to children.

There are two main groups of porphyrias: Acute porphyrias happen suddenly and usually last days or weeks. They mainly affect the nervous system. Sometimes they affect the skin, too.; Cutaneous porphyrias are long-lasting and affect only the skin, causing blisters or pain when you are exposed to sunlight; There are eight types of porphyria that fall into either of these groups.

Your symptoms and where excess porphyrins are in your body will help your health care provider determine a diagnosis of acute or cutaneous porphyria.

Why this test is done

You may need a porphyrin test if you have symptoms of porphyria. Each porphyria group has different symptoms:

Symptoms of acute porphyria may be mild or severe. Without early treatment, they may get worse and even become life-threatening. Symptoms may include:

• Pain in the abdomen (belly), back, or arms and legs
• Constipation
• Nausea and vomiting
• Mental changes, such as anxiety, confusion, and seizures
• Problems urinating (peeing), leaking urine, or red or brown urine
• Problems with nerves that control movement, which may cause muscle weakness, paralysis, and breathing problems
• Skin blisters when skin is in sunlight (for certain types of acute porphyria)

Symptoms of cutaneous porphyria happen when skin is exposed to sunlight.

Symptoms of some types of cutaneous porphyria include:

• Blisters
• Fragile skin that is easily wounded and slow to heal
• Infections in blisters or wounds
• Changes in skin color or scarring

Other types of cutaneous porphyria usually don't cause blisters. Instead, sunlight may cause these skin symptoms:

• Pain, burning, stinging, or tingling
• Redness
• Swelling

If someone in your family has porphyria, you may need a porphyrin test to see if you have inherited the condition. But the most common type of porphyria isn't inherited. It usually develops after age 30 and may be caused by conditions, such as:

• Hemochromatosis, a disease where too much iron builds up in the body
• Alcohol use disorder (AUD)
• Smoking
• Viral infections, such as hepatitis C and HIV
• Taking estrogen in medicines such as birth control pills or hormone replacement therapy

How to prepare

You don't need any special preparations for blood or urine tests.

For a stool test, you may be instructed to not eat meat or take any aspirin-containing medicines for three days prior to your test.

Sample type

Blood Urine Stool

Other names for this test

protoporphyrin; protoporphyrin, blood; protoporhyrin, stool; porphyrins, feces; uroporphyrin; porphyrins, urine; Mauzerall-Granick test; acid; ALA; porphobilinogen; PBG; free erythrocyte protoporphyrin; fractionated erythrocyte porphyrins; FEP