Etiological Agent and Their Antibiotic Susceptibility Pattern Causing Adult Septicaemia in a Critically Ill Patients in a Tertiary Care Setting

Abstract

Objective: To determine bacterial profile in adult sepsis with their antimicrobial susceptibility pattern in our setup.

Study Design: Cross-sectional study.

Place and Duration of Study: Microbiology Department, Armed Forces Institute of Pathology, Rawalpindi Pakistan, from Dec 2018 to Dec 2019.

Methodology: Paired blood culture was collected in automated bottles and was processed as per standard protocol. The isolates were further identified and their susceptibility was performed according to Clinical and Laboratory Standards Institute (CLSI) 2019 guidelines.

Results: A total of 580 suspected septicaemia cases were taken into consideration. 169 (29.4%) were positive on blood cultures. Among culture-positive samples, Gram-negative bacilli (GNB) accounted for 113 (66.3%) isolates, while the remaining 56 (33.1%) were gram-positive isolates. Within gram-negative isolates, the most common species were 36 (31.8%) Klebsiella pneumonia, followed by 27 (23.8%) Acinetobacter species and 15 (13.2%) Escherichia coli. Multi-drug resistance (MDR) was observed in 98 (86.7%) isolates. Extended-spectrum beta-lactamase production (ESBL) was reported in 73 (64.6%) of enterobacterial. Among 56 Gram-positive bacterial isolates, 25 (44.6%) were Methicillin-resistant Staphylococcus aureus (MRSA), 23 (41%) were Methicillin-resistant coagulase-negative Staphylococcus (MR-CONS). Of the isolates, 8 (14%) were Methicillin sensitive Staphylococcus aureus (MSSA). None of the MR-CoNS and S. aureus strains was resistant to vancomycin.

Conclusion: Gram-negative bacilli outnumbered Gram-positive organisms in adult septicaemic patients. The majority of these organisms were multidrug-resistant, necessitating the need for timely culture and adjusting antimicrobials according to susceptibility profile.