The effect of immunosuppressive therapy on the development of ventilator-associated pneumonia in patients with COVID-19

Abstract

Aim: It remains unclear whether immunosuppressive treatments such as corticosteroids and IL-6 receptor blockers have an effect on the development of ventilator-associated pneumonia (VAP). The aim of this study was to investigate the effect of immunosuppressive therapy on the development of VAP in critically ill patients with COVID-19.
 Material and Method: Two hundred thirty five patients with critically ill patients with COVID-19, who were treated in the intensive care unit (ICU) and received mechanical ventilator support, were evaluated retrospectively. VAP development, secondary infections, microorganisms isolated, and resistance patterns were compared between the groups that received and did not receive immunosuppressive therapy, and also the groups that did not receive immunosuppressive therapy, received only corticosteroid, received only tocilizumab, and received corticosteroid plus tocilizumab were compared in the subgroup analysis.
 Results: In the immunosuppressive treatment group, VAP development (40.2% vs. 21.2%; p=0.001), secondary infection development (48.4% vs. 29.2%; p=0.003), at least one drug resistant bacteria growth (46.7% vs. 27.4%; p=0.001), extensively-drug resistant (XDR) microorganism growth (89.8% vs. 72.7%; p=0.033) were higher than the group that did not receive immunosuppressive treatment. VAP (53.3%; p=0.004), secondary infection (73.3%; p=0.0002), the growth of bacteria resistant to at least one drug (70%; p=0.0003) were highest in the corticosteroid plus tocilizumab group in the subgroup analysis. In addition, XDR (95.5% vs. 72.7%; p=0.032) and pan-drug resistant (PDR) microorganism growth (31.8% vs. 9.1% p=0.032) were higher in the corticosteroid plus tocilizumab group than the no immunosuppressive therapy group. There was no difference between the groups in terms of mortality (p>0.05).
 Conclusion: Immunosuppressive therapy has been found to potentially enhance the risk of VAP and secondary infections in critically ill patients with COVID-19 pneumonia as well as the growth of bacteria resistant to at least one drug, the length of stay in hospital and ICUs. In addition, it has been evaluated that there may be an increase in the growth of XDR and PDR microorganisms when corticosteroid and tocilizumab are used together. Although there was no difference in mortality, using immunosuppressive therapy may require careful use of targeted antibiotics and longer-term antimicrobial therapy.