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Published on: March 3, 2023
Bloodstream Coinfections and Antimicrobial Resistance in Hospitalized COVID-19 Patients: A Single-center
Yu-Hsin Tsai1, Tai-Cheng Hou2, Po-Yu Liu3
1Department of Pathology and Laboratory Medicine, Taichung Veterans General Hospital, Taichung, Taiwan, R.O.C.
Background/Aim:
Bloodstream infections in patients with COVID-19 are linked to higher mortality rates, whilst data on epidemiology and resistance patterns remains scarce to guide management and prevent antibiotic resistance. This research focuses on the prevalence, clinical features, causative microorganisms, and antimicrobial susceptibility of bacterial and fungal secondary bloodstream co-infections in hospitalized patients with COVID-19.
Patients And Methods:
In this retrospective study analysis of 230 patients with COVID-19 from Central Taiwan (June 2021 to June 2022), pathogens were identified via MALDI-TOF MS and Vitek 2 system with Clinical & Laboratory Standards Institute (CLSI) standards.
Results:
In the cohort, 17.8% experienced bloodstream infections, resulting in a total of 45 isolates from the 41 bloodstream infection patients: predominantly gram-positive bacteria (Staphylococcus and Enterococcus) at 69%, gram-negative at 29% (Escherichia coli and Klebsiella pneumoniae), and fungi at 2%. Infected patients showed significantly elevated levels of white blood count (WBC), C-reactive protein (CRP) and procalcitonin (PCT). Of note, resistance to common antibiotics, such as fluoroquinolones, cephalosporins, and oxacillin was significant, especially in K. pneumoniae, Acinetobacter species, and S. aureus infections.
Conclusion:
Our study highlights the influence of bacterial infections in hospitalized patients with COVID-19. The bacterial infections were discovered to impact the clinical trajectory of COVID-19, potentially exacerbating or mitigating its symptoms, severity and fatality. These insights are pivotal to addressing clinical challenges in COVID-19 management and underscoring the need for tailored medical interventions. Understanding these co-infections is thus essential for optimizing patient care and improving overall outcomes in the post COVID-19 pandemic era.
Insights
Secondary bloodstream infections in COVID-19 patients are common and linked to higher mortality. Gram-positive bacteria were most frequent, with significant antibiotic resistance observed, impacting patient outcomes.
Area of Science:
- Infectious Diseases
- Critical Care Medicine
- Microbiology
Background:
- Bloodstream infections (BSIs) in COVID-19 patients increase mortality.
- Limited data exists on the epidemiology and resistance patterns of these co-infections.
- Understanding secondary infections is crucial for managing COVID-19 patients.
Purpose of the Study:
- To investigate the prevalence, clinical features, and causative agents of bacterial and fungal BSIs in hospitalized COVID-19 patients.
- To determine the antimicrobial susceptibility patterns of identified pathogens.
- To inform management strategies and combat antibiotic resistance.
Main Methods:
- Retrospective analysis of 230 COVID-19 patients in Central Taiwan (June 2021-June 2022).
- Pathogen identification using MALDI-TOF MS and Vitek 2 system.
- Antimicrobial susceptibility testing according to CLSI standards.
Main Results:
- 17.8% of patients had BSIs, yielding 45 isolates.
- Predominant pathogens: Gram-positive bacteria (69%), Gram-negative bacteria (29%), and fungi (2%).
- Significant antibiotic resistance observed in *K. pneumoniae*, *Acinetobacter* spp., and *S. aureus*.
Conclusions:
- Bacterial co-infections significantly influence the clinical course of COVID-19.
- These infections can exacerbate or mitigate COVID-19 symptoms, severity, and fatality.
- Tailored interventions and understanding co-infections are vital for optimizing patient care post-pandemic.

