Comparison of the clinical characteristics and severity of community-acquired pneumonia between patients with rheumatoid arthritis treated with tocilizumab and those treated with TNF inhibitor.

To examine the clinical characteristics and severity of community-acquired pneumonia (CAP) between patients with rheumatoid arthritis (RA) treated with tocilizumab (TCZ) and those treated with TNF inhibitors. We extracted RA patients treated with biological DMARDs who developed CAP between 2003 and 2015 from our hospital database. We compared the patient backgrounds, duration from the onset of symptoms to diagnosis, and the severity of CAP between patients who developed CAP after treatment with TCZ or tumor necrosis factor (TNF) inhibitor. Of 98 patients who received TCZ, seven developed CAP (IL-6 inhibitor group). Of 560 patients who received TNF inhibitors, 27 developed CAP (TNF inhibitor group). Between the two groups, there was no difference in the duration from the onset of symptoms to diagnosis (7 [4-21], 7 days [1-15]). The IL-6 inhibitor group had a lower body temperature (36.5 °C [36.4-36.8], 37.8 °C [35.9-40.5]) and CRP level (0.09 mg/dL [0.02-2.5], 6.76 mg/dL [0.63-15.2]) at diagnosis than the TNF inhibitor group. The CURB-65 score did not differ significantly between groups. There were no delays in the diagnosis of CAP or any difference in the severity of CAP between patients with RA treated with TCZ and those treated with TNF-inhibitors.