Glucose-6-Phosphate Dehydrogenase (G6PD) Test

The G6PD enzyme is normally present in cells and plays a protective role in the body. G6PD present in RBCs protects them against harmful and toxic compounds. These toxic compounds like reactive oxygen species (ROS) build up in the body due to some foods, medicines and diseases or infections. Therefore, cells like RBCs will become vulnerable to haemolysis when they are deficient in the enzyme. The G6PD test measures the levels of G6PD in the blood, helping in the screening and diagnosis of G6PD deficiency, which is a genetic disorder.

Why is the test ordered?

The test may be ordered to screen and diagnose Glucose-6-phosphate dehydrogenase deficiency, as well as to monitor children who as new-borns had unexplained persistent jaundice. The test may be helpful in establishing diagnosis for individuals of any age group, who have had jaundice and unexplained episodes of haemolytic anaemia. The test may also be ordered to people who got exposed to a trigger like some drugs foods or have had a recent bacterial or viral infection followed by a haemolytic episode.

When is the test ordered?

The test may be ordered when a physician suspects destruction of RBCs or haemolytic anaemia in a patient. The signs and symptoms associated with the condition include

General weakness

Breathlessness

Fainting

Brown or red urine

Blood in urine

Enlarged spleen

Rapid heart rate

Pale skin

The test may also be recommended when other lab tests are suggestive of haemolytic anaemia.

How is the sample collected?

A blood sample is collected from a vein.

How to prepare for the test?

No special preparations are required for this test.