tetano
Editor, Senior Moderator
Respir Investig
. 2025 Sep 3;63(6):1087-1092.
doi: 10.1016/j.resinv.2025.08.006. Online ahead of print. Bacterial pneumonia co-infection in adult inpatients with coronavirus disease 2019 during the Omicron variants epidemic in Okinawa, Japan: risk factors and clinical outcomes
Wakaki Kami[SUP] 1 [/SUP], Shuhei Ideguchi[SUP] 2 [/SUP], Kazuya Miyagi[SUP] 3 [/SUP], Daisuke Tasato[SUP] 4 [/SUP], Futoshi Higa[SUP] 5 [/SUP], Hideta Nakamura[SUP] 3 [/SUP], Takeshi Kinjo[SUP] 3 [/SUP], Masashi Nakamatsu[SUP] 6 [/SUP], Shusaku Haranaga[SUP] 7 [/SUP], Akihiro Tokushige[SUP] 8 [/SUP], Jiro Fujita[SUP] 9 [/SUP], Kazuko Yamamoto[SUP] 3 [/SUP]
Affiliations
Background: The clinical characteristics and risk factors for bacterial pneumonia co-infection in patients with coronavirus disease 2019 (COVID-19) since the epidemic of Omicron variants remain unclear.
Methods: This retrospective study included adult inpatients with COVID-19 at four tertiary hospitals in Okinawa, Japan, between May and July 2023. Bacterial pneumonia co-infection was diagnosed on the basis of new infiltrates on chest radiography, the presence of neutrophils on sputum Gram stain with a positive culture, and the requirement for antimicrobial therapy. We evaluated patient characteristics, detected microbes, assessed patient outcomes, and analyzed the risk factors for bacterial pneumonia co-infection.
Results: Among 458 patients initially considered, 358 were eligible (median age 77 years; 55 % male, and 19 % unvaccinated against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Bacterial pneumonia was identified in 60 patients (17 %). The most common pathogens were Klebsiella pneumoniae, Staphylococcus aureus, and Haemophilus influenzae, with oral flora detected in 40 % of cases. Mortality was significantly higher in patients with bacterial pneumonia than in those without. Multivariate analysis identified age, male sex, cerebrovascular disease, delayed antiviral therapy, and lower oxygen saturation to fraction of inspired oxygen ratio as independent risk factors for bacterial pneumonia co-infection.
Conclusions: Co-infection with bacterial pneumonia significantly affected the outcomes of patients with COVID-19 during the XBB Omicron variant epidemic. Early antiviral therapy and targeted prevention strategies, particularly for patients with cerebrovascular disease, can help reduce the risk of bacterial pneumonia-associated complications.
Keywords: Bacterial pneumonia; COVID-19; Co-infection; SARS-CoV-2; XBB.
. 2025 Sep 3;63(6):1087-1092.
doi: 10.1016/j.resinv.2025.08.006. Online ahead of print. Bacterial pneumonia co-infection in adult inpatients with coronavirus disease 2019 during the Omicron variants epidemic in Okinawa, Japan: risk factors and clinical outcomes
Wakaki Kami[SUP] 1 [/SUP], Shuhei Ideguchi[SUP] 2 [/SUP], Kazuya Miyagi[SUP] 3 [/SUP], Daisuke Tasato[SUP] 4 [/SUP], Futoshi Higa[SUP] 5 [/SUP], Hideta Nakamura[SUP] 3 [/SUP], Takeshi Kinjo[SUP] 3 [/SUP], Masashi Nakamatsu[SUP] 6 [/SUP], Shusaku Haranaga[SUP] 7 [/SUP], Akihiro Tokushige[SUP] 8 [/SUP], Jiro Fujita[SUP] 9 [/SUP], Kazuko Yamamoto[SUP] 3 [/SUP]
Affiliations
- PMID: 40907109
- DOI: 10.1016/j.resinv.2025.08.006
Background: The clinical characteristics and risk factors for bacterial pneumonia co-infection in patients with coronavirus disease 2019 (COVID-19) since the epidemic of Omicron variants remain unclear.
Methods: This retrospective study included adult inpatients with COVID-19 at four tertiary hospitals in Okinawa, Japan, between May and July 2023. Bacterial pneumonia co-infection was diagnosed on the basis of new infiltrates on chest radiography, the presence of neutrophils on sputum Gram stain with a positive culture, and the requirement for antimicrobial therapy. We evaluated patient characteristics, detected microbes, assessed patient outcomes, and analyzed the risk factors for bacterial pneumonia co-infection.
Results: Among 458 patients initially considered, 358 were eligible (median age 77 years; 55 % male, and 19 % unvaccinated against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Bacterial pneumonia was identified in 60 patients (17 %). The most common pathogens were Klebsiella pneumoniae, Staphylococcus aureus, and Haemophilus influenzae, with oral flora detected in 40 % of cases. Mortality was significantly higher in patients with bacterial pneumonia than in those without. Multivariate analysis identified age, male sex, cerebrovascular disease, delayed antiviral therapy, and lower oxygen saturation to fraction of inspired oxygen ratio as independent risk factors for bacterial pneumonia co-infection.
Conclusions: Co-infection with bacterial pneumonia significantly affected the outcomes of patients with COVID-19 during the XBB Omicron variant epidemic. Early antiviral therapy and targeted prevention strategies, particularly for patients with cerebrovascular disease, can help reduce the risk of bacterial pneumonia-associated complications.
Keywords: Bacterial pneumonia; COVID-19; Co-infection; SARS-CoV-2; XBB.