Abstract:
Background: Burn wound is one of the most common, devastating and painful trauma.
Infection remains the most common cause of morbidity and mortality in burn patients.
Information on local pathogens and sensitivity to antimicrobial agents is crucial for
successful treatment of these infections.
Aim: To determine bacterial causes of BWI and antibiotic susceptibility patterns of aerobic
isolates from burn patients at tertiary and regional hospitals in Dar es Salaam, Tanzania.
Methods: This was a cross-sectional study that was conducted between May and July
2017. Burn wound swabs were collected from patients with signs of wound infection.
Swabs were cultured on blood agar and MacConkey agar and incubated aerobically at
37°C for 18–24 hours. In addition, a blood sample was collected from patients with a
history of fever and/or temperature of ≥ 38º C. Bacterial identification was done using
conventional method and API20E. Antimicrobial susceptibility was determined by KirbyBauer
disk diffusion method.
Results: A total of the 70 patients with clinically diagnosed burn wound infections had
their wound cultured. Sixty six (94%) had positive bacterial growth after overnight
incubation. A total of 131 pathogenic bacteria were isolated, with gram negative organisms
91(69.5%) being more prevalent. The most frequently isolated bacteria were Pseudomonas
aeruginosa (26%), followed by Acinetobacter spp (22%) and Coagulase negative
staphylococci (CoNS) (18%), Klebsiella spp (11%) and Staphylococcus aureus (9.9%).
CoNS were most common in BSI. Proportion of BSI among patients with BWI was 37.5%.
Chloramphenicol was found to be most effective drugs towards gram positive bacteria and
Klebsiella, while imipenem was effective against Acinetobacter spp. Up to 73%
Enterobacteriaceae were extended spectrum beta-lactamase producers, while 61% of
Staphylococci spp were resistant to methicillin. Proportion of MDR among all isolates was
73.5%. Two (2/70, 2.9%) paediatric patients died during the period of the study.
Conclusions and recommendations: P. aeruginosa was the most common isolate in BWI
while CoNS were common in BSI. Most of the organisms isolated were resistant to
commonly prescribed antibiotics. High proportion of infections were due to ESBL
producers and methicillin resistance staphylococci spp. Routine culture and antimicrobial
susceptibility testing should be performed before the start of therapy; including MRSA and
ESBL screening