Procalcitonin Test: Normal Values
May 11, 2022
Source: Cainiu Health
Dr. Pan Yongyuan
Introduction
The normal reference range for procalcitonin (PCT) is primarily determined by immunoassay methods. When measured using colloidal gold colorimetric assay, the normal value is less than 0.5 ng/mL. When detected via immunohistochemistry, the lower limit of normal should be less than 0.1 pg/mL; whereas with radioimmunoassay (RIA), the assay sensitivity can reach 4 pg/mL. PCT levels are influenced by numerous different factors.
Procalcitonin (PCT) levels in plasma also serve as an indicator of overall health status. Below are the reference (normal) values for procalcitonin testing:
Normal Reference Values for Procalcitonin Testing
Normal PCT values are primarily determined using immunoassay methods. When measured by colloidal gold colorimetric assay, the normal value is <0.5 ng/mL. For immunohistochemical detection, the lower limit of normal is <0.1 pg/mL; whereas radioimmunoassay offers a sensitivity of up to 4 pg/mL. PCT levels are influenced by numerous factors, including the size and type of infected organ, the causative bacterial species, the severity of infection and inflammation, and the status of the host’s immune response—factors that are often overlooked.
Procalcitonin is a protein whose plasma concentration rises significantly in severe infections—including bacterial, fungal, or parasitic infections—as well as in sepsis and multi-organ failure. In contrast, PCT levels typically remain unchanged in autoimmune disorders or viral infections, and do not increase with localized, mild, or chronic inflammatory conditions. Thus, PCT serves as a valuable biomarker for clinical diagnosis and assessment of infection severity.
Avoid consuming excessively fatty or high-protein foods the day before blood collection, and refrain from excessive alcohol intake. Blood alcohol concentration can directly affect test results. A 12-hour fast is required prior to blood sampling, and freshly drawn blood should be submitted for analysis promptly. We hope this information is helpful to you!
