PORPHOBILINOGEN (PBG) – RANDOM URINE – HM044
⚡ Emergency Acute Porphyria ScreenPBG degrades immediately in sunlight. The urine sample must be collected in a sterile container and immediately wrapped in aluminum foil or black paper to block all light. Do not expose the sample to the sun.
📋 Test Details
- Report Time: 3rd Working Day.
- Sample Type: Random (Spot) Urine.
- Condition: During active symptoms (pain/attack).
- Test Code: HM044
What is the PBG Random Urine Test?
Porphobilinogen (PBG) is a chemical that builds up in the body when someone has Acute Porphyria, a rare genetic disorder affecting heme production.
This Random (Spot) urine test is used as an emergency screen. Unlike the 24-hour test which takes a full day to collect, this test uses a single urine sample taken while the patient is experiencing symptoms (like severe stomach pain). It helps doctors quickly rule in or rule out Porphyria as the cause of the pain.
When is this Test Prescribed?
It is usually ordered in emergency settings for patients presenting with the classic Triad of Porphyria symptoms:
- Acute Abdominal Pain: Severe, unexplained stomach pain that doesn't show up on scans.
- Neurological Symptoms: Confusion, seizures, anxiety, or muscle weakness.
- Dark Urine: Urine that turns reddish-purple (port wine color) when left standing.
Random vs. 24-Hour Test: Which one do I need?
Random Urine (HM044): Best for active emergencies. If you are in pain right now, this test is faster and sufficient to detect the massive spike in PBG caused by an attack.
24-Hour Urine (HM043): Best for confirmation and monitoring. It provides a precise quantity of PBG excreted over a full day.
Frequently Asked Questions
No. Fasting is not required. In fact, severe dieting or fasting can sometimes trigger a Porphyria attack, so you should eat normally unless advised otherwise by your doctor.
PBG is photosensitive. If sunlight hits the urine sample, the PBG breaks down chemically. This means the lab might find Low PBG even if you actually have high levels (False Negative), leading to a wrong diagnosis.
You can, but it is less accurate. PBG levels are highest during an attack. Between attacks (latency period), levels might drop to near normal, making it harder to diagnose via a random sample.
Disclaimer: Porphyria is a rare and complex condition. Results should be interpreted by a Hematologist or Gastroenterologist.