From July 1st, 2026, serum calprotectin measurement by nephelometry will be included in our laboratory test panel.
Calprotectin, a heterodimeric complex composed of the S100A8 and S100A9 proteins, is a well-established biomarker of inflammation. It is predominantly released by activated neutrophils and monocytes. While fecal calprotectin measurement is widely used in the monitoring of inflammatory bowel diseases, increasing evidence supports the clinical utility of its quantification in serum.
Recent studies have highlighted the relevance of serum calprotectin in the assessment of inflammatory activity in several autoimmune and autoinflammatory disorders, including juvenile idiopathic arthritis (JIA), Still’s disease, rheumatoid arthritis (RA) with normal C-reactive protein (CRP) levels, and ankylosing spondylitis. In addition, its use has been proposed for monitoring patients receiving anti–IL-6 therapies.
Owing to its rapid kinetics, serum calprotectin represents a sensitive biomarker for the evaluation of disease activity. It may thus contribute to the early detection of disease flares and persistent subclinical inflammation, thereby supporting therapeutic decision-making and treatment monitoring. Current recommendations from the European Alliance of Associations for Rheumatology (EULAR) and the American College of Rheumatology (ACR) endorse its use in Still’s disease and JIA (Fautrel et al., 2024), as well as in IL-1–mediated autoinflammatory diseases (Romano et al., 2022).
Furthermore, the potential role of serum calprotectin has been investigated in infectious conditions, including severe COVID-19 and septic shock, where it may serve as a marker of disease severity and systemic inflammatory response.
Code analyze: CALPS