Procalcitonin Normal Values
May 10, 2022
Source: Cainiu Health
Dr. Pan Yongyuan
Introduction
The normal reference range for procalcitonin primarily depends on the immunoassay method used. When colloidal gold colorimetric assay is employed, the normal value is <0.5 ng/mL. When chemiluminescent immunoassay is used, the normal upper limit is <0.1 ng/mL. With radioimmunoassay, the detection sensitivity can reach 4 pg/mL.
Procalcitonin (PCT) is currently one of the most widely used biomarkers for diagnosing bacterial infection. It exhibits a relatively rapid response and high sensitivity, particularly in febrile patients. So, what constitutes the normal reference range for procalcitonin?
Normal Reference Range for Procalcitonin
The normal reference range for procalcitonin primarily depends on the immunoassay method employed. When using colloidal gold colorimetric assay, the normal value is <0.5 ng/mL. With chemiluminescent immunoassay, the lower limit of normal is <0.1 ng/mL. Radioimmunoassay offers higher sensitivity, with a detection limit of up to 4 pg/mL.
Procalcitonin is a protein whose plasma concentration increases significantly in severe infections—including bacterial, fungal, or parasitic infections—as well as in sepsis and multi-organ dysfunction syndrome. In contrast, procalcitonin levels typically remain unchanged in autoimmune disorders, allergic reactions, or viral infections. Likewise, localized infections, mild infections, or chronic inflammatory conditions generally do not cause elevated procalcitonin levels—making it a highly valuable tool for clinical diagnosis and differentiation of infectious etiologies.
A procalcitonin level exceeding 0.5 ng/mL often suggests bacterial infection; levels above 2.0 ng/mL raise concern for severe infection or sepsis; and values greater than 5.0 ng/mL warrant heightened vigilance for septicemia or even septic shock. We hope this information is helpful. Wishing you good health and happiness!
