FAQ: How is calprotectin useful to monitor treatment response in rheumatoid arthritis?
25. May 2021 |
8 min read
Calprotectin levels correlate with disease activity in rheumatoid arthritis (RA)1-3 and can therefore be used in monitoring of disease activity, treatment response and relapse4-6. Calprotectin has been reported as valuable tool to monitor patients receiving a variety of different treatments, including disease-modifying anti-rheumatic drugs (DMARDs)7,8 like methotrexate6,9, tumour necrosis factor inhibitors (TNFi)10-12, IL-6 inhibitors13.
Why is calprotectin especially important to monitor patients treated with DMARDs?
Disease-modifying anti-rheumatic drugs (DMARDs) are frequently used to treat inflammation and underlying inflammation pathways in RA. They target pro-inflammatory proteins, like TNF-alpha and IL-6, directly. The resulting decrease in systemic inflammatory signalling will also decrease activity of downstream proteins and processes, like activity of acute‐phase reactants erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP). Since CRP and ESR are often used as inflammatory biomarkers in RA, the direct effect of the treatment on CRP might lead to an overestimation of the patients’ response rate. In contrast, calprotectin is released locally from phagocytes, independently of systemic inflammatory signalling, and has been shown to more accurately discriminate disease activity in RA patients receiving TNFi than CRP and ESR10 and more strongly correlate with treatment response to methotrexate than CRP6.
Can calprotectin in blood predict relapse in RA?
Calprotectin can be used to accurately predict relapse in patients in remission or with low disease activity receiving biological drugs, which potentially would guide therapeutic decisions towards safer and more cost-effective treatment strategies10,13,14.