@article{GernertSchmalzingTonyetal.2022, author = {Gernert, Michael and Schmalzing, Marc and Tony, Hans-Peter and Strunz, Patrick-Pascal and Schwaneck, Eva Christina and Fr{\"o}hlich, Matthias}, title = {Calprotectin (S100A8/S100A9) detects inflammatory activity in rheumatoid arthritis patients receiving tocilizumab therapy}, series = {Arthritis Research \& Therapy}, volume = {24}, journal = {Arthritis Research \& Therapy}, number = {1}, doi = {10.1186/s13075-022-02887-7}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-300523}, year = {2022}, abstract = {Background Assessing serological inflammation is difficult in tocilizumab (TCZ)-treated rheumatoid arthritis (RA) patients, as standard inflammation parameters, like erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP), are influenced by interleukin-6-receptor inhibition. Calprotectin in the serum, also named S100A8/S100A9, might be a more useful inflammation parameter in TCZ-treated patients. Methods Sixty-nine RA patients taking TCZ were included. Serum-calprotectin levels were assessed, as well as ESR, CRP, need for a change in disease-modifying anti-rheumatic drugs due to RA activity (= active RA), and the RA clinical disease activity score (CDAI). Forty-five RA patients taking tumor-necrosis factor-inhibitors (TNFi) were investigated for the same parameters. Results TCZ-treated patients with active RA had higher calprotectin values than not active RA patients (4155.5 [inter quartile range 1865.3-6068.3] vs 1040.0 [676.0-1638.0] ng/ml, P < 0.001). A calprotectin cut-off value of 1916.5 ng/ml resulted in a sensitivity and specificity of 80.0 \%, respectively, for the detection of RA disease activity. Calprotectin values correlated with CDAI-scores (r = 0.228; P = 0.011). ESR and CRP were less suitable to detect RA activity in TCZ-treated patients. Also TNFi-treated patients with active RA had higher calprotectin values compared to not active RA (5422.0 [3749.0-8150.8] vs 1845.0 [832.0-2569.0] ng/ml, P < 0.001). The calprotectin value with the best sensitivity and specificity for detecting RA activity was 3690.5 ng/ml among TNFi-treated patients. Conclusion Calprotectin in the serum can be a useful inflammation parameter despite TCZ-treatment.}, language = {en} }