Sputum-Cultivated Pathogenic Bacterium Distribution And Drug Resistance Involving 421 Pediatric Patients With Lower Respiratory Tract Infection

Objective To understand sputum-cultivated pathogenic bacterium distribution and drug resistance analysis on pediatric patients suffered from lower respiratory tract infection, and to guide the rational drug administration in clinic.Methods 421 sputum samples of pediatric patients with lower respiratory tract infection were collected for routine bacterial cultivation and antibiotic sensitivity test.Identification of bacterial strains were performed by ATB system and VITEK system.Antibiotic sensitivity test adopted Kirby-Bauer method. The results were evaluated according to the standards of the Clinical and Laboratory Standards Institute (USA).Results Totally 232 bacteria strains were isolated.From them 80(34.5%) were Gram-positive bacteria,133(57.3%) were Gram-negative bacteria, and 19 (8.5%) were fungi.Among the isolated gram-positive bacteria, Strep tococcus Pneumoniae was the most (acounting for 37.17%), and the next was staphylococcus aureus (41.8%).In the isolated gram negative bacteria, Escherichia coli(27.8%) was the most, and the next was Klebsiella pneumonice and Haemophilus influenzae (respectively acounting for 21.8%). The isolating rate of MRSA was15.2%. The incidences of E.coli,K.pneumoniae and Haemophilus influenzae isolates extended-spectrum beta-lactamases (ESBL)-producing bacteria were 18.9%,17.2% and 3.5%.The majority of fungi was C.glabrata, acounting for 52.6%, and the next was fungemia 36.8%. The antibiotic susceptibility of Strep tococcus Pneumoniae to linezolid,vano mycin and levofloxacin was over 80%, while resistance rate to erythromycin and Cotrimoxazole was over 90%. The sensitive rate of Staphylococcus aureus to linezolid,vano mycina and levofloxacinw was more than 65%, but to penicillins, the resistant rate was 87.9%. More than 90% of E.coli and K.pneumoniae were sensitive to imipenem, while over 50% were resistant to ceftazidime and other commonly used antibiotics. Among the MRSA, all were rrsistant to penicillins and oxacillin and none were resistant to linezolid and vano mycin. ESBLs was most sensitive to imipenem, on the other hand, the resistance rate to gentamici,cotrimoxazole,ampicillin/sulbactam and amoxycillin clarulanic acid was over 50%. Fungi were almost sensitive to commonly used antifungal agents.Conclusion Gram negative bacteria were the main pathogenic bacteria involving in pediatuic respiratory tract infection of our city. The gram negative bacteria were most sensitive to imipenem.The gram positive coccobacteria were most sensitive to vano mycin. Fungi were mostly sensitive to commonly used antifungal agents. We should attach importance to identify the bacterial strains and give susceptibility tests of them, rationally use antibacterial drug in order to rase clinical healing effect and slow the development of the resistant bacterial flora.