The Biochemical Features, Physiological Actions, And Clinical Importance of Procalcitonin: A Review

Abstract

Procalcitonin (PCT), a peptide precursor of calcitonin, has emerged as an important biomarker (biomarker) clinically that can be used for diagnosis and subsequent management of bacterial infection. This review summarizes the biosynthesis, biochemical characteristics, physiological functions and clinical relevance of procalcitonin. PCT is produced by thyroid C cells under physiological conditions, and almost immediately converted to calcitonin giving rise to extremely low levels in circulation. In contrast, during systemic bacterial infections it is produced in relatively high states in various tissues with a corresponding increase in serum concentrations. From a biochemical perspective, PCT is representative of a “hormokine,” bridging the immune and endocrine responses. On a physiological level, it helps to regulate inflammation and immune responses. Clinically, PCT has been used as a sensitive and specific biomarker for bacterial infections and sepsis, making it a valuable tool in differentiating disease causing by viral infection from that of bacterial origin. Moreover, antibiotic therapy based on PCT reduces unnecessary antibiotic therapy and improves treatment outcome. Procalcitonin is an important supporting diagnostic and prognostic biomarker, which undoubtedly has limitations but supports appropriate clinical decision-making and patient care in different medical contexts.

 

Keywords:

Prohormone, Procalcitonin, C–cells, Parathyroid

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