Microbiological Profile and Their Antibiotic Susceptibility Pat-Tern – Experience in a Tertiary Care Hospital in Bangladesh

Background: It is essential to monitor causative agents of infections and antimicrobial resistance patterns to inform treatment and policy at the local level. In this study, we investigated the microbiological profile and antibiotic susceptibility pattern records in a tertiary care hospital. Materials and Method: This cross-sectional study was performed in a tertiary care hospital in Dhaka city, Bangladesh. The study utilized a retrospective descriptive research approach conducted between January 2018 and February 2021 in which culture results of blood, stool, urine, body fluid, genital, respiratory and soft tissue specimens were retrieved and analyzed. Results: A total of 26,825 samples were ana-lyzed; of which 3,779 records for microbial growth from clinical specimens were identi-fied, yielding a 14.09% isolation rate. Escherichia coli (E. coli), Klebsiella sp., Staphylo-coccus aureus, Pseudomonas sp., coagulase negative Staphylococcus, Salmonella Typhi and Enterococcus sp. were the most frequently isolated organisms among all specimens. E. coli, the most common causative organism of urinary tract infection (UTI) and genital infection, showed high resistance to co-trimoxazole (48%), ciprofloxacin (79%), and cephalosporins (63-65%) while the resistance rate to nitrofurantoin (7%), mecillinam (16%), aminoglycosides (7-18%), meropenem (8%) and colistin (0%) was low. In bloodstream infection, the most common microorganism found was S. Typhi. High sensitivity towards amoxicillin (100%), chloramphenicol (78%), co-trimoxazole (76%), cefixime (100%) and ceftriaxone (100%) were seen in S. typhi whereas almost all isolates were resistant to nalidixic acid (97%) and ciprofloxacin (96%). S. aureus, the predominant cause of soft tissue infection, was highly sensitive to co-trimoxazole (70%), doxycycline (86%), and linezolid (97%). Methicillin-resistant Staphylococcus aureus (MRSA) was 54%. The most common cause of respiratory infection was Klebsiella sp. The rate of resistance of Klebsiella sp. to third and fourth generation cephalosporins was approximately 65% and to ciprofloxacin and meropenem was 74% and 42% respectively. Pseudomonas sp., found commonly in urine, soft tissue, body fluids, and respiratory infections, were susceptible to ceftazidime, piperacillin/tazobactam and ciprofloxacin with resistance rate of 27%, 18% and 34% re-spectively. High resistance to meropenem was recorded for Pseudomonas sp. (30%) and Acinetobacter sp. (64%). Acinetobacter sp. showed low sensitivity (< 45%) to all of the tested antibiotics except colistin and tigecycline. Conclusion: This study highlights the high potential for infections associated with resistant microorganisms in the tertiary care hospital where samples for this study were collected. It is therefore recommended that judicious treatment following drug-susceptibility testing of isolates, regular surveillance programs, and strict infection control measures be put into place to address this increasing drug resistance problem.