Antimicrobial susceptibility patterns of bacteria isolated from open fracture infections at Mulago Hospital.

Abstract

Introduction. Infections are a common complication of open fractures; they are associated substantially with prolonged hospital stay, leading to higher treatment cost, morbidity and mortality, particularly when the etiological bacteria are multidrug resistant. Knowledge of the infecting bacteria and their antibiotic sensitivity patterns is very important in our setting where routine treatment is given without doing culture and sensitivity. Objective. To determine the antimicrobial susceptibility patterns of bacteria isolated from open fracture infections at Mulago hospital. Methodology. This was a descriptive cross sectional study involving 134 patients with infected open fractures between September 2013 and March 2014 at Mulago Hospital. Participants who met the inclusion criteria were consecutively recruited into the study. Pus aspirate and swabs were taken from infected open fractures for microscopy, culture and antibiotic sensitivity profiling. The data collected was entered into EPIDATA 3.02 exported to STATA Version 11 for analysis. Descriptive (mean, standard deviation and interquartile range) and inferential (Chi square and Fishers exact tests) statistics were used to analyse data. Alpha level was set at p < 0.05. RESULTS Multidrug resistant gram-negative and gram positive organisms were isolated. Pseudomonas spp 26(18.2%), Klebsiella spp 25(17.4%) and Acinetobacter spp 23(16.1%) were the commonest gram negative organisms isolated while Staphylococcus aureus 8(5.6%) and Enterococcus spp 3(2.1%) were the commonest isolated gram positive organisms. The isolated gram negative bacteria were sensitive (>80%) to Amikacin, Piperacillin and Imipenem but resistant (>80%) to, Ampicillin, Augmentin, Ceftriaxone, Ceftazidime, Cefuroxime and Co-trimoxazole. The isolated gram positive bacteria; Staphylococcus aureus were sensitive (>80%) to Vancomycin, Chloramphenicol, and Oxacillin but resistant (71.4%) to Co-trimoxazole. Meanwhile, Enterococcus spp were sensitive (50%) to Vancomycin and Tetracycline but were resistant (100%) to Chloramphenicol, Ciprofloxacin and Gentamycin. There was significant statistical association between the duration of injury and bacteria isolated (p= 0.006). CONCLUSION AND RECOMMENDATIONS. Multidrug resistant gram negative bacteria, Pseudomonas spp, Klebsiella spp, Acinetobacter spp, Enterobacter spp, Escherichia coli and Proteus spp are associated with open fracture infections at Mulago hospital. These multidrug resistant gram negative bacteria were sensitive to Amikacin, Imipenem, and Piperacillin. The isolation of multidrug resistant gram negative bacteria calls for laboratory guided therapy, strengthening infection control surveillance, identification of the source of these multidrug resistant bacteria, development of an antibiotic protocol for management of open fractures and we suggest use of Amikacin, Imipenem and Piperacillin for treatment of the multidrug resistant gram negative open fracture infections at Mulago hospital.