Pyogenic skin infections by Gram Negative Rods- carbapenems are still the saviors??

Abstract

Introduction- Pyoderma is defined as “any pyogenic infection of the skin”. Pyodermas are classified as primary or secondary and superficial or deep.Staphylcooccus aureus, Streptococcus pyogens, Escherichia coli, Klebsiella species, Pseudomonas aeruginosa, Acinetobacter species are common causes of pyoderma. Culture still remains the mainstay of diagnosis. Antibiotic susceptibility testing(AST) should be performed and reported to avoid unnecessary use of drugs. Aims and objectives- The objectives of the study were- 1.To isolate and identify the causative agents of pyodermas.2.To determine the antimicrobial profile of isolated Gram negative bacterias.Material and methods- 400 samples were collected from patients presenting with pyogenic skin infections attending Out Patient Department (OPD) and admitted in wards. The samples were transported in Cary Blair medium. Gram staining was done and culture was done on blood agar, MacConkey Agar and Nutrient Agar. Antibiotic susceptibility testing was performed according to Kirby Bauer disk diffusion method.Results- Out of 400 clinically suspected cases of pyoderma, male:female ratio was 1.16:1. 21-40 years age group was more commonly affected in both the sexes. Out of 400 samples, growth was found in 85.5% cases and no growth was there in 14.5% cases. Gram positive isolates were 266(74.93%) and Gram negative isolates were 89 (25.07%).Amongst Gram negative bacteria, Escherichia coli, Klebsiella species, Pseudomonas aeruginosa, Acinetobacter species were common causes. Primary pyoderma was more common(60.25%) cases. We found that, most of the Gram negative bacteria were sensitive to carbapenems and piperacillin and tazobactam. Resistance was noted to Amoxicillin and clavulanic acid, cefotaxime and ceftazidime. Conclusion- Gram Negative Bacteria are less common cause of pyoderma as compared to Gram positive bacteria. They are still sensitive to combination of piperacillin and tazobactam as well as carbapenems which indicates that, Antibiotic susceptibility testing should be performed and higher antibiotics like colistin should not be started immediately.