Bacterial Isolates from Wound Infections and Their Antibiotic Susceptibility Pattern in Kassala Teaching hospital, Sudan

Abstract

BACKGROUND: Wound infections are usually caused by the patient’s normal flora or by bacteria from the environment or the skin of hospital staff and surgical wound infection which consider as most important causes of morbidity and mortality worldwide The commonest organism of Gram positive is Staphylococcus aureus, Gram negative bacteria which include E. coli, Proteus spp. Klebsiclla spp. and Ps. Aerogenosa. [1]. OBJECTIVES: Isolation and identification of bacteria from wounds and burns infection and antibiotic susceptibility of the isolated bacteria. MATERIALS AND METHODS: A total of 756 wound swabs were collected from different infected wounds from the outpatient and inpatients admitted in the ward of surgery of Kassala teaching hospital were included in this study. All the swab and pus samples collected were tested for the direct microscopy, culture, biochemical reaction and antibiotic susceptibility tests was applied for all isolated bacteria. Analytical profile index (API system) plus conventional techniques were used in identification of bacterial isolates. The McFarland 0.5 standard was used to adjust the turbidity of the inoculum for the susceptibility test. Antibiotic susceptibility pattern of the isolates was assessed by Modified Kirby Baur disc diffusion technique. RESULTS: During this period of study (756) samples were collected from different infected wounds from Kassala teaching hospital. (76.7%) were male and (23.3%) were female. Types of wounds observed from seven hundred and fifty six (756) patients were of two groups either non-operative/primary wound (82%) and post operative infection (18%). Positive growth was observed in 92.6% (700) of wound cultures and no bacterial isolates were obtained in 7.4 %( 76). From the culture materials Staphylococcus aureus was the most frequently isolated microorganism 30% followed by Staphylococcus epidermids 19%, Escherichia coli (18 %) Pseudomonas aeruginosa (12%) Klebsiella pneumoniae (8%) Proteus mirabilis (7%) and Streptococcus pyogenes (6%). Antibiotic disc were exposed to 385 Gram positive isolates 239 (62%) were resistant and 146(38%) were susceptible, (210) Staphylococcus aureus of which 81(38.6%) were susceptible and 129(61.4%) were resistant, (133) Staph. epidermidis of which 51(38.3%) were susceptible and 82 (61.7%) were resistant and (42) Streptococcs pyogeneus 14 (33.3%) susceptible and 28(66.7%) resistant and 223 out of 315 Gram negative isolates (70.8%) were resistant and 92 (29.2%) were susceptible Antibiotic susceptibilities for (126) E. cooli shows 53(42%) susceptible and 73(58%) resistant, (84) Pseudomonas shows 14 (16.7%) susceptible and 70(83.3%) resistant, (56) Klebsiella shows 23 (41%) susceptible and 33 (59%) resistant, and (49) Proteou shows 45 (92%) resistant and 4(8%) susceptible. CONCLUSION: Microbiological analysis of the wound specimen and their antibiotic susceptibility testing are recommended that will guide medical practitioners for empirical treatment of wound infection, so as to reduce the spread of resistant bacteria.