Pathologic bacterial distribution and antibiotic resistance in induced sputum of infants aged from 1 to 3 months with lower respiratory tract infection
ZUO Man-Feng1, LIU He-Lin1, ZHU Mu-Liang2, SHU Qiong-Zhang1, JIANG Ling1
Department of Pediatrics, Xiaogan Central Hospital Affitiated to Tongji Medical College of Huazhong University of Science and Technology, Xiaogan, Hubei 432100, China
Abstract：Objective To investigate the pathologic bacterial distribution and their antibiotic resistance in infants aged from 1 to 3 months with lower respiratory tract infection, so as to provide instructions for clinical application of antibiotics. Methods Induced sputum was extracted from 622 cases of hospitalized infants aged from 1 to 3 months with lower respiratory tract infection between January 2013 and December 2013, and microbial sensitivity test was performed with agar diffusion sensitivity test. Results A total of 379 (60.9%) strains of bacteria were isolated from induced sputum in the 622 infants. The Gram-negative strains were detected in 325 strains (85.8%), and the Gram-positive strains were found in 50 strains (13.2%) in the 379 strains. The others were Fungal strains (4 strains, 1.1%). The Gram-negative bacteria included Escherichia coli (31.1%) and Klebsiella pneumoniae (18.2%), with extended-spectrum β-lactamases (ESBLs) production of 48.3% and 52.2% respectively. The average rate of antibiotic resistance for ESBLs-producing bacteria was 53%. ESBLs-producing bacteria were highly resistant (100%) to ampicillin and cefotaxime, but sensitive to carbapenems. Staphylococcus aureus (10.0%) was the dominant bacteria in Gram-positive bacteria. A lower proportion of methicillin-resistant Staphylococcus aureus (1.8%) was observed, however the resistance rate of methicillin-resistant Staphylococcus aureus to β-lactam antibiotics were 100%. Conclusions Escherichia coli and Klebsiella pneumoniae are the main pathogenic bacteria causing lower respiratory tract infection in infants aged from 1 to 3 months. ESBLs-producing bacteria accounted for over 48%, and the antibiotic resistance rate were more than 53% in these infants. These results provide a basis for the first empirical clinical use of antimicrobial in infants with lower respiratory tract infection.
ZUO Man-Feng,LIU He-Lin,ZHU Mu-Liang et al. Pathologic bacterial distribution and antibiotic resistance in induced sputum of infants aged from 1 to 3 months with lower respiratory tract infection[J]. CJCP, 2014, 16(12): 1226-1230.
