Identification, Antimicrobial Resistance Profiling and Virulence Factors of Bacterial Isolates Recovered from Human Clinical Cases

Antimicrobial Resistance (AMR) among different microorganisms has become a serious issue and contributing to cause severe diseases. Proper monitoring measures should be taken to improve the current scenario of antimicrobial resistance. The present study focuses on identification, antimicrobial resistance profiling and virulence factors of bacterial isolates recovered from various human clinical cases. Total 350 clinical samples were collected from a public hospital in Shimla (Himachal Pradesh) and a private diagnostic centre in Mohali (Punjab). K. pneumoniae (51.42%) and E. coli (44.57%) were recovered from all the sample sources while S. aureus (3.15%) and Bacillus spp. (0.86%) were isolated from urine samples only. Overall maximum resistance was observed against ampicillin (94.28%), amoxicillin + clavulanic acid (90.5%), cefepime (88%) and ceftriaxone (80.18%) while it was minimum for cefoperazone (0.85%), kanamycin (1.14%), lomefloxacin and norfloxacin (1.42% each) and cefixime (1.71%). 52.28% isolates were multidrug-resistant (MDR) and 13.42% were extensive drug resistant (XDR). Drug resistant phenotypes were prominently observed in isolates recovered from tracheal fluid and cerebrospinal fluid (CSF). The expression of selective virulence factors like motility, lipase, protease and capsule production was evenly associated with drug-resistant and drug-sensitive bacterial phenotypes; however, siderophore and biofilm production was only seen among isolates with drug resistant phenotype. A significant relation between both the variables was statistically confirmed using chi-square test and the probability value (p < 0.05) for calculated c2 of 43.28 with degree of freedom 10. Occurrence of MDR and XDR bacterial strains among clinical samples bring on economic burden on health system as well as on patient in terms of longer hospital stays and treatment delays.