Alarming increase in carbapenemase-producing Klebsiella spp causing bloodstream infections in pediatric population in India

Dear Editor, Carbapenemases are a versatile group of βlactamases characterized by their resistance to virtually all β-lactam antibiotics, including cephalosporins and carbapenems. This retrospective study was conducted to monitor the change in the trend of carbapenemresistant (CR) Klebsiella spp causing bloodstream infections (BSI) in patients ≤15 years of age during January 2010 to November 2015 at Christian Medical College, Vellore, South India. Antimicrobial susceptibility testing was done by disk diffusion method as per CLSI guidelines, and isolates that were resistant to both imipenem and meropenem were included in the analysis. All the CR-Klebsiella spp were characterized by both phenotypic and molecular methods for carbapenem resistance. The total of Klebsiella spp isolated from BSIs over a five year period were as follows: 29 (2010), 77 (2011), 49 (2012), 45 (2013), 78 (2014) and 27 (2015). Of these, CR rates were found to be 28% (n = 8/29), 19% (n = 15/77), 22% (n = 11/49), 22% (n = 10/45), 37% (n = 29/78) and 33% (n = 9/27) in 2010 to 2015, respectively. Most of the CR Klebsiella spp exhibited co-resistance to penicillins, cephalospotins and other classes of drugs, except colistin and tigecycyline. Among the CRKlebsiella spp, 39 isolates were randomly chosen and screened for the carbapenemases genes blaNDM, blaSPM, blaIMP, blaVIM and blaOxa-48 like [1]. Of the 39 isolates tested, 27, 3, 4 and 1 isolates were positive for blaNDM,, blaOxa-48-like, blaNDM+Oxa-48-like and blaNDM+VIM genes, respectively. Four isolates were negative for all the five genes tested. Notably, sequencing of two each of blaNDM and blaOxa48like positives revealed that all sequenced isolates contained blaNDM-1 and blaOxa-181 gene variants, respectively. A similar observation was seen in the adult population as well (unpublished data), which points towards a local transmission of these gene variants within the hospital. Such local dissemination of resistant genes in the hospital and community increases the CR Enterobacteriaceae rates over the years. Among the isolates tested, blaNDM gene was found to be the most prevalent, followed by blaOxa-48-like genes among the pediatric population. Moreover, the rates of CR Klebsiella spp were increased from 28% in 2010 to 33% in 2015 (Figure 1). This issue was addressed in our previous study where 22% of the Klebsiella spp exhibited resistance to carbapenems [2]. In recent years,