Anti-tumor necrosis factor drugs are frequently preferred in the treatment of rheumatologic diseases and other inflammatory diseases. The development of myositis after using anti-tumor necrosis factor drugs is a rare clinical condition. Here we aimed to report cases who developed myositis after using anti-tumor necrosis factor drugs and review the current literature. We report two cases of rheumatoid arthritis and a case of ankylosing spondylitis developed idiopathic inflammatory myopathy following anti-tumor necrosis factor therapy. In conclusion, myositis could develop during anti-tumor necrosis factor therapy, so these patients should be evaluated carefully initially for myositis and should be closely monitored due to the potential for developing myositis in treatment process.

Objective.: The effect of smoking in psoriatic arthritis (PsA) is under debate. Our aim was to test whether smoking is increased in axial PsA (axPsA).Methods.: Included in the analysis were 1535 patients from PsArt-ID (PsA-International Database). The effect of smoking on axPsA (compared to other PsA phenotypes) and radiographic sacroiliitis were investigated.Results.: Current smoking was more common in axPsA (28.6% vs 18.9%, p < 0.001). It also was found as an independent predictor of axPsA (OR 1.4) and radiographic sacroiliitis (OR 6.6).Conclusion.: Current smoking is significantly associated with both axPsA and radiographic sacroiliitis in patients with PsA.

To evaluate treatment adherence and predictors of drug discontinuation among patients with inflammatory arthritis receiving bDMARDs within the first 100 days after the announcement of COVID-19 pandemic. A total of 1871 patients recorded in TReasure registry for whom advanced therapy was prescribed for rheumatoid arthritis (RA) or spondyloarthritis (SpA) within the 3 months (6-9 months for rituximab) before the declaration of COVID-19 pandemic were evaluated and 1394 (74.5%) responded the survey performed by phone call. Patients? data regarding demographic, clinical characteristics and disease activity before the pandemic were recorded. The patients were inquired for the diagnosis of COVID-19, the rate of continuation on bDMARDs, the reasons for treatment discontinuation, if any, and the current general disease activity (visual analog scale, [VAS]). A total of 1,394 patients (493 RA [47.3% on anti-TNF] patients and 901 SpA [90.0% on anti-TNF] patients) were included. Overall, 2.8% of the patients had symptoms suggesting COVID-19, and 2 (0.15%) patients had polymerase chain reaction (PCR) confirmed COVID-19. Overall, 18.1% of all patients (13.8% of the RA and 20.5% of the SpA; p=0.003) discontinued their bDMARDs. In the SpA group, the patients who discontinued bDMARDs were younger (40 [21-73] vs. 44 years [20-79]; p=0.005) and had higher general disease activity; however, no difference was relevant for RA patients. Although the COVID-19 was quite uncommon in the first 100 days of the pandemic, nearly one-fifth of the patients discontinued bDMARDs within this period. Long-term effects of the pandemic should be monitored.