Porphobilinogen - Qualitative
What is PBG, Qual.?
Haemoglobin protein in red blood cells responsible for carrying oxygen in blood is a type of porphyrin which is formed from the intermediate Porphobilinogen (PBG). Porphyrins do not accumulate in the body and get excreted via urine or stool. In case they are not released from the body, there is a signal where they are getting accumulated. Hence, the PBG qualitative test diagnoses porphyria in the urine.
Why is PBG, Qual. done?
The test is performed when either porphyria or an associated disorder is suspected due to the presence of certain symptoms such as pain in the limbs, backache, abdominal pain, rapid heart-beat, nausea and vomiting
Interpreting PBG, Qual. results
A normal test result indicates absence of PBG in urine sample and is considered as a negative test which implies that the symptoms caused are not due to porphyria but some other disorder. An abnormal result implies presence of PBG in high concentration.