Prevalence and Incidence of carbapenem-resistant K. pneumoniae colonization: systematic review and meta-analysis

Abstract Background: Klebsiella pneumoniae is a gram-negative rod belonging to the order Enterobacterales and having a wide distribution in the environment, including the human colon. Recently the bacterium is one of the known problems in the healthcare setting as it has become resistant to last-resort drugs like carbapenems. The colonized person can serve as a reservoir for his/herself and others, especially in the healthcare setting leading to nosocomial and opportunistic infections. Therefore, we aimed to quantitatively estimate the rate of prevalence and incidence of colonization with carbapenem-resistant K. pneumoniae.Methods: A literature search was conducted on PubMed/MEDLINE, Google Scholar, Science Direct, Cochrane Library, WHO Index Medicus, and others. All studies (published and unpublished) addressing the prevalence/ incidence of K. pneumoniae colonization were included in the study. Data were extracted onto format in Microsoft Excel and pooled estimates with 95% confidence interval calculated using Der-Simonian-Laird random-effects model. The degree of heterogeneity was presented with I2 statistics and prediction intervals. Publication bias was presented with funnel plots of standard error supplemented by Egger's tests. Results: A total of 35 studies were included in the review and 32 records with 37,661 patients for assessment of prevalence while ten studies with 3643 patients were used for incidence of colonization. The prevalence of colonization with carbapenem-resistant K. pneumoniae ranges from 0.13% to 22% with variation in different localities with a pooled prevalence of 5.43% (3.73-7.42). Whereas the incidence of colonization ranges from 2% to 73% with a pooled incidence of 22.3% (CI: 12.74-31.87), both prevalence and incidence reports are majorly from developed countries. There was a variation in the distribution of carbapenem resistance genes among colonizing isolates with KPC as a major gene reported from many studies and NDM being reported mainly by studies from Asian countries. A univariate meta-regression analysis indicated continent, patient type, study design, and admission ward do not affect the heterogeneity (p-value>0.05).Conclusion: The review revealed that colonization with K. pneumoniae is higher in a healthcare setting with variable distribution in different localities, and resistance genes for carbapenem drugs also have variable distribution in different geographic areas.