CPT® Code 84106

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.