Antimicrobial Susceptibility Pattern of Isolates From Diabetic Foot Ulcers

Objective: To identify different organisms from diabetic foot ulcers and their antibiotic susceptibility. Study Design: It was an institution based descriptive cross sectional study. Place and Duration of Study: The study was conducted at Rehman Medical Institute, Hayatabad, Peshawar from 1 June 2017 to 31 December 2018. Materials and Methods: A total of 88 specimen have been collected from a sample of 60 diabetic patients who have clinically infected foot ulcers and 99 pathogens wereisolated. The samples includes pus, tissue and fluid under study were cultured on blood agar and McConkey plates. Anaerobic culture medium 1 (AN1) was used for isolating anaerobes. The micro-organisms were identified through gram staining, culture and analytical profile index 20E. The sensitivity to a particular antibiotic was determined by Kirby-Bauer disk diffusion method.Anti-microbial susceptibility testing of isolates was performed as per the guidelines recommended by the Clinical Laboratory Standard Institute (CLSI). Results: The most commonly isolated organisms were Escherichia coli (36.2%), Staphylococcus aureus (80%), Klebsiella pneumoniae (13%) and Pseudomonas aeruginosa (11.6%). Polymicrobial growth was found in 19 cultures. The ratio of gram-negative and gram-positive organisms isolated was 2.3. Gram-negative bacteria accounted for 69.7%, while gram-positive bacteria accounted for 30.3%. Staphylococcus aureus (87%) isolates were resistant to penicillin, ampicillin, levofloxacin, ceftriaxone & cefoxitin. High levels of resistance to amoxicillin/Clavulanic acid 15 (93.57%), ampicillin 20 (100%), ciprofloxacin 17 (89.47%) and co-trimoxazole 12 (85.71%) was seen in Escherichia coli. Conclusion: E. coli are the most common pathogen isolated from diabetic foot ulcers. Their antibiograms suggest that resistance is on the rise and antimicrobial therapy should be selected based on culture results and antimicrobial sensitivity patterns.