Aerobic Bacteriological and Antibiotic Susceptibility Profile of Pus Isolates from A Tertiary Care Hospital, Puducherry

The antibiotic resistance pattern was observed significantly in various geographical locations. Routine surveillance is therefore essential for constant monitoring of AMR rates in the clinically important pathogens. It is imperative to track the changing resistance pattern over time, to guide proper therapeutic strategies to combat infections due to drug-resistant pathogens. This study aims to highlights the distribution of aerobic bacterial isolated from pus samples, and their susceptibility to different antibiotics collected during 2017 (July to December) in a tertiary care hospital. Nearly 637 clinical pus samples were received during July to December 2017 to the Department of Microbiology, Tertiary care hospital, Puducherry. Bacterial identification was performed using standard conventional biochemical tests and antibiotic susceptibility was carried out according to CLSI guidelines 2017 on each one of the aerobic bacterial isolates from the pus samples. Among the isolates 76.5% were Gram-negative bacilli (GNB) as well as 23.5% were Gram-positive cocci (GPC). The most common bacteria isolated were Pseudomonas spp 24.88% (108 in 434), followed by Escherichia coli 21.66% (94 in 434), Staphylococcus aureus 19.82% (86 in 434) and Klebsiella pneumoniae 13.13% (57 in 434). Of the 86 (19.82%) Staphylococcus aureus isolates, 16 (18.40%) were MRSA. Pseudomonas aeruginosa was highly susceptible to the carbapenems and least susceptible to ciprofloxacin. Acinetobacter baumannii was the most resistant organism according to this study and showed the least susceptibility to ceftriaxone and maximum susceptibility to aminoglycosides. This study concluded that the Pseudomonas aeruginosa isolate was found to be a predominant in our clinical pus samples. Gram negative bacteria are more commonly associated with the pyogenic lesion that Gram positive. A high level of an antibiotic resistance was observed in most of our bacterial isolates.