Predictors and microbiology of respiratory and bloodstream bacterial infection in patients with COVID-19: author's response

Abstract

We thank the authors for their interest and comments regarding our publication [[1]Langford B.J. So M. Leung V. Raybardhan S. Lo J. Kan T. et al.Predictors and microbiology of respiratory and bloodstream bacterial infection in patients with COVID-19: living rapid review update and meta-regression.Clin Microbiol Infect. 2022; 28: 888-889Abstract Full Text Full Text PDF Google Scholar]. Given the vast amount of literature published on the topic of coinfections and secondary infections with coronavirus disease 2019, as well as the heterogeneity in publication quality, methodological approach, and data reporting strategies, it was necessary to make some assumptions regarding whether studies met the inclusion criteria. We agree there are certainly limitations that may affect the precision of our estimate and have highlighted some of these concerns in our discussion. Nevertheless, each of the 171 studies was reviewed by a minimum of two authors to determine if the inclusion criteria were met. However, the inclusion of some studies may still be debatable. Although serological testing was an exclusion criterion, certain studies did not specify the microbiological method of testing [[2]Chen T. Dai Z. Mo P. Li X. Ma Z. Song S. et al.Clinical characteristics and outcomes of older patients with coronavirus disease 2019 (COVID-19) in Wuhan, China: a single-centered, retrospective study.J Gerontol A Biol Sci Med Sci. 2020; 75: 1788-1795Crossref PubMed Scopus (238) Google Scholar] and did not explicitly indicate that serological testing was used (e.g. studies may have used PCR or serology to detect Mycoplasma spp.); hence, these studies were included. We also made the decision to include studies of patients with ventilator-associated pneumonia (without further microbiological detail) because the vast majority of cases are caused by bacteria [[3]Luyt C.E. Hékimian G. Koulenti D. Chastre J. Microbial cause of ICU-acquired pneumonia: hospital-acquired pneumonia versus ventilator-associated pneumonia.Curr Opin Crit Care. 2018; 24: 332-338Crossref PubMed Scopus (52) Google Scholar,[4]Kalanuria A.A. Mirski M. Ziai W. Ventilator-associated pneumonia in the ICU.in: Vincent J.L. Annual update in intensive care and emergency medicine. Springer International Publishing, New York City, NY2014: 65-77Google Scholar]. Our meta-analysis and regression specifically focused on concomitant infection caused by bacteria, so all studies counted towards an estimate of bacterial coinfection or bacterial secondary infection. Please note that the final two columns in Table S1 indicate bacterial coinfection and bacterial secondary infection. We hope this helps clarify. Our exclusion of letters to the editor was meant to remove any commentary or narrative-type correspondence. However, we did include research letters that provided sufficient data to meet the inclusion criteria [[5]Lee S. Koh J.S. Kim Y.J. Kang D.H. Park D. Park H.S. et al.Secondary infection among hospitalized COVID-19 patients: a retrospective cohort study in a tertiary care setting.Respirology. 2021; 26: 277-278Crossref PubMed Scopus (7) Google Scholar,[6]Elabbadi A. Turpin M. Gerotziafas G.T. Teulier M. Voiriot G. Fartoukh M. Bacterial coinfection in critically ill COVID-19 patients with severe pneumonia.Infection. 2021; 49: 559-562Crossref PubMed Scopus (36) Google Scholar]. Given some of these limitations mentioned, we have updated the inclusion criteria in our living review so that our next update will be more stringent with respect to study inclusion (e.g. requiring an explicit statement of microbiological testing approach, exclusion of any type of letter/correspondence) [[7]Langford B.J. So M. Leung V. Simeonova M. Lo J. Raybardhan S. et al.Antibiotic resistant infections in patients with COVID-19: a rapid review.Prospero. 2021; (CRD42021297344)Google Scholar]. The full search strategy for our most recent rapid review is now included in the supplementary material. The authors have no relevant conflicts of interest to declare. No external funding was received for this project. Writing—original draft BJL; writing—review and editing: MS, VL, SR, JL, TK, FL, ND, DRM, JPS. The following is the Supplementary data to this article: Download .docx (.55 MB) Help with docx files Multimedia component 1 Re: predictors and microbiology of respiratory and bloodstream infection in patients with COVID-19Clinical Microbiology and InfectionVol. 28Issue 6PreviewWe read the latest systematic review and meta-analysis by Langford et al. with great interest [1]. The authors provide a high-quality review concerning the incidence and microbiological predictors of respiratory and bloodstream bacterial infections in COVID-19 patients. Among other exclusion criteria, they chose to exclude editorials and letters, studies in which bacterial infection was only presumed or suspected, and studies in which serology was used as a bacterial infection diagnostic approach. Full-Text PDF