CPT® Code 84106

Official Description

Porphobilinogen, urine; qualitative

Common Language Description

Porphobilinogen (PBG) is a type of porphyrin, which is a group of organic compounds that play a crucial role in the body's production of heme, an essential component of hemoglobin found in red blood cells. Under normal circumstances, the body metabolizes PBG and other porphyrins into heme through a series of enzymatic reactions. However, when there is a deficiency in the enzymes responsible for this process, porphyrins, including PBG, can accumulate in the body, leading to various health issues. The qualitative testing of PBG in urine is primarily conducted to assist in the diagnosis of porphyria, a hereditary metabolic disorder characterized by the inadequate functioning of enzymes in the heme synthesis pathway. Since porphyrins are excreted in urine, the analysis of urine samples is a practical method for detecting the presence of PBG. The qualitative assessment of PBG is typically performed using the Watson-Schwartz test, which helps determine whether PBG is present in the urine. In contrast, quantitative measurements of PBG levels can be obtained through a different CPT® code, which involves collecting a 24-hour urine sample or a random sample during acute symptomatic episodes, and analyzing it using quantitative ion exchange chromatography or spectrophotometry.

1. Indications

The qualitative testing of porphobilinogen (PBG) in urine is indicated for the following conditions:

Porphyria This inherited metabolic disorder is characterized by a deficiency of enzymes involved in the heme synthesis pathway, leading to the accumulation of porphyrins, including PBG, in the body.
Acute Symptoms Patients presenting with acute symptoms suggestive of porphyria may require PBG testing to confirm the diagnosis and guide further management.

2. Procedure

The procedure for qualitative testing of porphobilinogen in urine involves several key steps:

Sample Collection A urine sample is collected from the patient. This can be a random sample or, in some cases, a 24-hour urine collection may be preferred to ensure accurate results, especially during acute symptomatic periods.
Testing Method The collected urine sample is subjected to the Watson-Schwartz test, which is a qualitative method used to detect the presence of PBG. This test involves adding specific reagents to the urine sample and observing the resulting color changes, which indicate the presence of PBG.

3. Post-Procedure

After the qualitative testing of porphobilinogen in urine, the results are analyzed and interpreted by a qualified healthcare professional. If PBG is detected, further diagnostic steps may be warranted to confirm a diagnosis of porphyria or to rule out other conditions. Patients may be advised on follow-up testing or additional evaluations based on the results. It is important to consider that the presence of PBG in urine may necessitate further investigation into the patient's metabolic and genetic background to understand the underlying cause of the enzyme deficiency.

Short Descr	TEST FOR PORPHOBILINOGEN
Medium Descr	PORPHOBILINOGEN URINE QUALITATIVE
Long Descr	Porphobilinogen, urine; qualitative
Status Code	Statutory Exclusion (from MPFS, may be paid under other methodologies)
Global Days	XXX - Global Concept Does Not Apply
PC/TC Indicator (26, TC)	9 - Not Applicable
Multiple Procedures (51)	9 - Concept does not apply.
Bilateral Surgery (50)	9 - Concept does not apply.
Physician Supervisions	09 - Concept does not apply.
Assistant Surgeon (80, 82)	9 - Concept does not apply.
Co-Surgeons (62)	9 - Concept does not apply.
Team Surgery (66)	9 - Concept does not apply.
Diagnostic Imaging Family	99 - Concept Does Not Apply
CLIA Waived (QW)	No
APC Status Indicator	Conditionally packaged laboratory tests
Type of Service (TOS)	5 - Diagnostic Laboratory
Berenson-Eggers TOS (BETOS)	T1H - Lab tests - other (non-Medicare fee schedule)
MUE	1
CCS Clinical Classification	233 - Laboratory - Chemistry and Hematology