| Objective: This study is aimed at understanding the distribution of Gram-negativebacilli from nasopharynx of children admitted to the respiratory department of DalianChildren’s Hospital in China, determining the prevalence of extended spectrum beta-lactamase (ESBL) producing Gram-negative bacilli and drug sensitivity test, providingclinical evidence for reasonable choice of antibiotics.Methods: A prospective one year study was performed on children admitted torespiratory department at Dalian Children’s Hospital, China with acute respiratoryinfections from January2010to December2010. Pharyngeal specimens were taken from arandomly selected number of1190patients, admitted in the hospital. All the specimenswere first investigated for the presence of type of microorganism by being cultured onchocolate agar medium. The isolates were identified by colony morphology, Gram stainingtechnique and standardized tests. When GNB culture was positive, drug sensitivity test wascontinued. The ESBL producing GNB isolates were subjected to susceptibility testing usingKirby and Bauer (K-B) method of determining antimicrobial susceptibility.Results: From1190patients with acute respiratory infections studied over1year,764cases (64.2%) were males and426cases (35.8%) were females. Out of the1190cases,276cases of pathogenic strains of nasopharyngeal flora were detected,208cases werefound positive for Gram negative bacteria, the GNB positive rate was75.4%. The GNBprevalence was17.5%(208/1190) and18species were identified. The more prevalentspecies were Acinetobacter Baumanii21.2%(44/208), E.Coli19.2%(40/208), KlebsiellaPneumonia12.5%(26/208), Haemophillus Influenzae12%(25/208) and pseudomonasaeruginosa11.1%(23/208). The rate of ESBL producing strains was10.1%(21/208). We also found mixed infections with the rate of9.6%(20/208) of which13/20were mixedwith Enteriobacteriaceae. Out of the208positive patients for GNB,173cases (83.2%)were males and35cases (16%) were females showing significant difference in sexes (p>0.05). All ESBL producing isolates were found to be more resistant to the followingantibiotics Cefotaxime95.2%, Cefoperazone95.2%, Ceftriaxone95.2%, Ceftazidime95.2%, Cefepime100%, Mezlocillin95.2%, Piperacillin71.4%, Cefoperazone/Sulbactam,Piperacillin/Sulbactam95.2%and90.5%to cefoxitine. Susceptibility was100%toImipenem.Conclusion: Acinetobacter Baumanii is the most common GNB causing acuterespiratory infections among children in Dalian Children’s Hospital. E.Coli is the mostprevalent ESBL-producing strain. All ESBL producing isolates were found to be moreresistant to Cephalosporins (Cefotaxime, Cefoperazone, Ceftriaxone, Ceftazidime andCefepime) and more sensitive to β-Lactams with Sulbactam, Cefoxitine and Carbapenems.Therefore, β-Lactams with Sulbactam, Cefoxitine and Carbapenems will be chosen astreatment for acute respiration infection with ESBL-producing. |
