Risk factors for carbapenem-resistant Klebsiella pneumoniae infection: a systematic review and meta-analysis.

BACKGROUND

Carbapenem-resistant Klebsiella pneumoniae (CRKP) infections are increasingly prevalent. This meta-analysis aimed to identify key risk factors to inform prevention strategies.

METHODS

We searched PubMed and Web of Science up to October 2025 for studies on CRKP infection risk factors. Study quality was assessed using the Newcastle-Ottawa Scale. We computed pooled odds ratios (ORs) with 95% confidence intervals (CIs) and evaluated heterogeneity using the I 2 statistic and the Q-test, employing either fixed- or random-effects models as appropriate.

RESULTS

Seventeen studies (5,303 cases) were included. Prior hospitalization, APACHE II score, and diabetes were not associated with CRKP infection. Significant risk factors included ICU admission (OR = 4.42, 95% CI: 2.82-6.91), cardiovascular disease (OR = 4.52, 95% CI: 3.23-6.30), renal disease (OR = 2.31, 95% CI: 1.74-3.06), multiple invasive procedures (e.g., mechanical ventilation OR = 3.82, 95% CI: 2.46-5.92; urinary catheterization OR = 4.73, 95% CI: 3.33-6.72), and exposure to various antimicrobial classes, notably carbapenems (OR = 6.36, 95% CI: 5.16-7.83), and tetracyclines (OR = 11.79, 95% CI: 7.75-17.93), though the latter's high magnitude may be influenced by the limited number of studies and potential confounding by indication. Subgroup analysis showed the risks from mechanical ventilation and urinary catheterization were significantly higher in developing versus developed countries (p = 0.03 and p = 0.01, respectively).

CONCLUSION

ICU admission, specific comorbidities, invasive procedures, and broad antimicrobial exposure are key risk factors for CRKP infection. Enhanced aseptic techniques in developing countries are crucial to mitigate risk.

SYSTEMATIC REVIEW REGISTRATION: https://www.crd.york.ac.uk/PROSPERO/, CRD420251242025.