Bacterial Aetiology of Bloodstream Infection and Antimicrobial Resistance Pattern in a Tertiary Hospital of Northern Bangladesh: Analysis of Current Situation

Background: The objective of the present study was to identify the causative organisms of blood stream infection (BSI) and their resistance pattern to different antibiotics as well as prevalence of multi drug resistant (MDR) organisms in this region. This retrospective study included blood culture reports from 1899 suspected bacteraemia patients. Culture was done using BACT/Alert machine followed by culture on MacConkey (MC) agar, chocolate agar and blood agar plates. Isolated organisms were identified using standard laboratory procedures. Results: Total 383 bacterial isolates were yielded (rate of positive culture 20.2%). Staphylococcus aureus (41.8%) and Escherichia coli (41.8%) were most frequently isolated gram positive and gram-negative organisms respectively. Other commonly isolated organisms were Salmonella typhi (10.7%) and coagulase negative Staphylococci (CoNS) (3.9%). More than 90% isolated organisms were multidrug resistant. Salmonella typhi (95.1%) and Staphylococcus aureus (91.2%) showed most frequently isolated MDR strains. All the organisms showed high resistance rate against commonly used antibiotics like azithromycin, ciprofloxacin, and trimethoprim/sulfamethoxazole. Amoxycillin and clavulanic acid combination, cloxacillin and linezolid were sensitive against Staphylococcus aureus. Ceftriaxone as well as amikacin remained a sensitive drug to treat Salmonella typhi. Carbapenems and nitrofurantoin were mostly sensitive against all isolated organisms. Conclusion: Rational use of antibiotics based on regional epidemiology of causative organisms and sensitivity pattern can preserve the potentiality of available antibiotics and reduce the burden of MDR pathogens.