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Efficacy of Intravenous Colistin Monotherapy Versus Colistin Combined With Meropenem in Patients With
Mehwish Baig1, Sana Rahim1, Rashid Naseem Khan2
1Intensive Care Unit, Liaquat College of Medicine and Dentistry, Darul Sehat Hospital, Karachi, PAK.
Abstract:
Background Intensive care units frequently contend with infections caused by highly drug-resistant organisms, particularly Acinetobacter baumannii, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Enterobacterales (CRE), which often lead to high mortality rates. Colistin (colomycin) is employed to treat infections, notably extremely drug-resistant (XDR) bacteria. Antibiotic combination treatment is a frequently used tactic in this endeavour. However, the widespread use of antibiotics in synergy could result in the emergence of resistance and a rise in side effects, such as those linked to Clostridium difficile infection. The aim of the study was to assess and contrast the clinical results of intravenous colistin monotherapy with the combination of colistin and meropenem in patients experiencing MDR bacteremia resulting from Acinetobacter Baumannii, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Enterobacterales (CRE). Methods In this retrospective observational study, an analysis spanning two years, from June 2021 to June 2023, was conducted at a teaching hospital located in Karachi, Pakistan. The research involved the retrospective examination of medical records from 132 patients who had been diagnosed with MDR bacteremia. Patients were divided into two categories based on their treatment regimen, either intravenous colistin monotherapy or intravenous colistin combined with meropenem. Among the 132 patients included in the analysis, 66 underwent colistin monotherapy, while the other 66 received a combination of colistin and meropenem. The primary focus of evaluation in this study centered on the 14-day all-cause mortality, while secondary outcomes encompassed clinical success and microbiologic cure. Results The mean age of patients in both groups was comparable, and there were no noteworthy gender differences. Additionally, the distribution of infection types and the isolated pathogens showed no substantial distinctions between the two groups. The study revealed no statistically significant disparities in 14-day mortality, improvement in Sequential Organ Failure Assessment (SOFA) score, or the proportion of patients who were cured and survived between the two treatment groups. Conclusion The findings from this study lead to the conclusion that there exists no significant disparity in the efficacy of colistin monotherapy compared to the combination of colistin with meropenem in the treatment of MDR bacteremia stemming from Acinetobacter Baumannii, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Enterobacterales (CRE). The results provide a basis for future research and underscore the significance of ongoing endeavors to refine antibiotic treatment strategies in response to the worldwide issue of antibiotic resistance.
Insights
Colistin monotherapy and combination therapy with meropenem showed similar effectiveness for treating multidrug-resistant bacteremia. This finding suggests neither approach significantly impacts 14-day mortality or clinical outcomes in critical infections.
Area of Science:
- Infectious Diseases
- Pharmacology
- Critical Care Medicine
Background:
- Intensive care units face challenges with multidrug-resistant (MDR) organisms like Acinetobacter baumannii, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Enterobacterales (CRE).
- Colistin is a crucial treatment for extremely drug-resistant (XDR) bacterial infections, but combination therapies may increase resistance and side effects.
- Understanding optimal colistin-based treatment strategies is vital for managing severe bacterial infections.
Purpose of the Study:
- To compare the clinical outcomes of intravenous colistin monotherapy versus colistin combined with meropenem.
- To evaluate efficacy in patients with MDR bacteremia caused by specific Gram-negative pathogens.
- To inform antibiotic stewardship in the context of rising antimicrobial resistance.
Main Methods:
- Retrospective observational study of 132 patients with MDR bacteremia from June 2021 to June 2023.
- Patients received either intravenous colistin monotherapy (n=66) or colistin plus meropenem (n=66).
- Primary endpoint: 14-day all-cause mortality; secondary endpoints: clinical success and microbiological cure.
Main Results:
- No statistically significant differences were observed between the groups regarding 14-day mortality.
- Clinical success and microbiological cure rates were comparable between colistin monotherapy and combination therapy.
- Patient demographics, infection types, and isolated pathogens were similar across both treatment arms.
Conclusions:
- Intravenous colistin monotherapy is as effective as combination therapy with meropenem for MDR bacteremia caused by Acinetobacter Baumannii, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Enterobacterales (CRE).
- These findings support the judicious use of colistin monotherapy, potentially mitigating risks associated with combination treatments.
- Further research is warranted to optimize antibiotic strategies against MDR pathogens and combat global antimicrobial resistance.
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