LAB TEST

PBG urine test

Porphobilinogen (PBG) is one of several types of porphyrins found in your body. Porphyrins help form many important substances in the body. One of these is hemoglobin, the protein in red blood cells that carries oxygen in the blood. Porphyrins usually leave your body through urine or stools. If this process does not occur, porphyrins such as PBG can build up in your body. This article describes the test to measure the amount of PBG in a urine sample.

How the Test is Performed

After you provide a urine sample, it is tested in the lab. This is called a random urine sample. If needed, your health care provider may ask you to collect your urine at home over 24 hours . This is called a 24-hour urine sample. Your provider will tell you how to do this. Follow instructions exactly.

How to Prepare for the Test

Your provider may tell you to temporarily stop taking medicines that may affect the test results. Be sure to tell your provider about all the medicines you take. These include: Antibiotics and anti-fungal drugs Anti-anxiety drugs Birth control pills Diabetes medicines Pain medicines Sleep medicines Never stop taking…

How the Test will Feel

This test involves only normal urination, and there is no discomfort.

Why the Test is Performed

This test may be done if your provider suspects porphyria or another disorder associated with an abnormal PBG level.

Normal Results

For a random urine sample, a negative test result is considered normal. If the test is done on a 24-hour urine sample, the normal value is less than 4 milligrams per 24 hours (18 micromoles per 24 hours). Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or may…

What Abnormal Results Mean

An increased level of PBG in the urine may be due to: Hepatitis Lead poisoning Liver cancer Porphyria (several types)

Risks

There are no risks with this test.

References

Fogazzi GB, Garigali G. Urinalysis. In: Feehally J, Floege J, Tonelli M, Johnson RJ, eds. Comprehensive Clinical Nephrology . 6th ed. Philadelphia, PA: Elsevier; 2019:chap 4. Fuller SJ, Wiley JS. Heme biosynthesis and its disorders: porphyrias and sideroblastic anemias. In: Hoffman R, Benz EJ, Silberstein LE, et al,…

This is a summary. Read the full article at www.ucsfbenioffchildrens.org (reviewed 02/02/2023).

This page is general information and is not medical advice. It does not replace a registered doctor, and it is not a prescription or a recommendation to use any medicine or test. Prices are listed prices and may change. Always follow the advice of your doctor or pharmacist.