Etiological analysis of infection after eye surgery and the investigation of drug sensitivity

Abstract

Background Clinical researches showed that antimicrobial-resistance of bacterium is gradually serious.It is very important to master pathogen distribution and antimicrobial susceptibility after eye surgery.Objective This study was to investigate the distribution and drug sensitivity of pathogenic bacteria from ocular operative infection in 3-year duration to provide a reference for reasonable selection of antibiotics.Methods Sixtyfive positive specimens were obtained from 65 patients due to postoperative infection in Department of Ophthalmology of Shenzhou Hospital and Shengjing Hospital from 2009 January through 2011 December.The pathogenic bacteria were isolated and then the drug sensitivity test of conventional antibiotics was performed.Results Among the 65 ophthalmic specimens,35 strains of Gram-positive bacteria were isolated with the constituent ratio 53.8％,and 15 strains of Gram-negative bacteria accounted for 23.1％.Fungus was found in 15 cases with the constituent ratio 23.1％.Staphylococcus epidermidis accounted for 42.9％ in Gram-positive bacteria,and Pseudomonas aeruginosa accounted for 33.3％ in Gram-negative bacteria.Aspergillus was the main component of fungus,which accounted for 60.0％ of the proportion 3 strains of methicillin-resistant Staphylococcus aureus (MRSA) in 8 strains of Staphylococcus aureus,but no vancomycin-resistant Enterococcus (VRE) and vancomycin-resistant Staphylococcus (VRS) were seen.The in vitro drug sensitivity test showed that the main Gram-positive bacteria,Staphylococcus epidermidis and Staphylococcus aureus,were sensitive to linezolid,vancomycin,levofloxacin and ciprofloxacin with the sensitive rates ＞50.0％,and these bacteria were lowly sensitive to penicillin and erythromycin with the sensitive rates ≤30.0％.Pseudomonas aeruginosa appeared to be the main Gram-negative bacteria,showing a sensitive rate ≥ 80.0％ to tobramycin,amikacin,ceftazidime,cefepime,cefoperazone/sulbactam,piperacillin/tazobactam,imipenem and meropenem.Conclusions Staphylococcus epidermidis,Staphylococcus aureus,Pseudomonas aeruginosa and Aspergillus are primary pathogens in ocular infection after operation.Antibiotics such as penicillin,erythromycin,levofloxacin,cefotaxime seem to be relatively high resistant to eye infection.To choose sensitive antibiotics timely and reasonably is a key to the prevention and control of ocular infection after operation. Key words: Ophthalmic surgery; Infection; Bacterium; Fungus; Antibiotics