Coincidence of sputum smear and culture results of children with lower respiratory tract infection

Abstract:

ObjectiveTo compare sputum smear  and culture results in children with lower respiratory infection，realize the laboratory diagnostic value of sputum smear, and analyze the distribution and antimicrobial resistance of cultured pathogens in infection, so as to guide rational antimicrobial use in clinic.MethodsQualified sputum specimens collected from hospitalized children with lower respiratory tract infection from March to May 2014 were conducted gramstaining after smeared, meanwhile, bacterial culture, identification and antimicrobial susceptibility testing of sputum specimens were performed, gramstaining microscopic examination and culture results were compared.ResultsThe overall coincidence rate of sputum smear and culture results was 67.43%(n=617), positive rate of sputum culture was 65.90%(n=603); 730 pathogenic strains were isolated， the top 3 isolated pathogens were Haemophilus parainfluenzae(36.17%), Streptococcus pneumoniae(24.38%), and Moraxella catarrhalis(13.29%).βlactamaseproducing rates of Haemophilus parainfluenzae, Haemophilus influenzae, and Moraxella catarrhalis were 44.70%（118/264）,45.83%（11/24）,and  93.81%（91/97）respectively. Streptococcus pneumoniae were susceptible to most antimicrobial agents, while resistant rates to erythromycin, tetracycline, and compound sulfamethoxazole were high， vancomycin,  linezolid, and/or moxifloxacinresistant strains were not found.ConclusionSputum smear has certain laboratory diagnostic value, gramstaining is recommended  while sputum culture is performed, antimicrobial agents should be used rationally according to antimicrobial susceptibility testing results， so as to reduce the emergence of antimicrobialresistant organisms.