Capsular Serotyping and Antimicrobial Drug Resistance of Klebsiella pneumoniae Strains Isolated from a Tertiary Care Hospital, Southern India

摘要

The rapid spread of Hypervirulent Klebsiella pneumoniae (hvKP) and Multi Drug Resistant (MDR) strains among the clinical isolates of K.pneumoniae is a great deal of concern. The drug resistance and limited treatment options are the major threats. However, the spread of drug resistant strains is through plasmid which may carry virulence determinants such as capsular antigens.Aim: To know the occurrence of hvKP; to study the occurrence of various capsular serotypes such as K1, K2, K3 and K4 among the isolates of K. pneumoniae using Co-agglutination (Co-A) test; to know the occurrence of beta lactamase genes (bla genes) among the K1, K2, K3 and K4 positive serotypes of K. pneumoniae. The study also tried to assess the reproducibility of Co-A test by comparing the result with PCR.Materials and Methods: A prospective study was carried with a total of 60 consecutive, non-duplicate isolates of K. pneumoniae recovered from various clinical specimens obtained from both outpatients and inpatients between April to December 2017. To determine the occurrence of hvKP by string test, the identification of various serotypes was done by Co-A test and PCR. The determination of beta lactamase genes such as blaTEM, blaSHV and blaCTX-M among the capsular serotypes was done by PCR study.Results: Rate of typability by Co-A was found to be 13(21.67%), 0(0%), 32(53.33%), 7(11.67%) for K1, K2, K3 and K4, respectively. Eight (13.33%) of them remained untypable. The rate of typability among the K. pneumoniae K1 serotype by Co-A test and PCR remained somewhat similar.Conclusion: Co-A test is a good method of serotyping and can be used not only for diagnostic purpose but also for epidemiological study.