title: Emergence of macrolide-resistant Mycoplasma pneumoniae with a 23S rRNA gene mutation.
abstract: A total of 195 Mycoplasma pneumoniae strains were isolated from 2,462 clinical specimens collected between April 2002 and March 2004 from pediatric outpatients with respiratory tract infections. Susceptibilities to six macrolide antibiotics (ML), telithromycin, minocycline, levofloxacin, and sitafloxacin were determined by the microdilution method using PPLO broth. A total of 183 M. pneumoniae isolates were susceptible to all agents and had excellent MIC90s in the following order: 0.00195 microg/ml for azithromycin and telithromycin, 0.0078 microg/ml for clarithromycin, 0.0156 microg/ml for erythromycin, 0.0625 microg/ml for sitafloxacin, 0.5 microg/ml for minocycline, and 1 microg/ml for levofloxacin. Notably, 12 ML-resistant M. pneumoniae strains were isolated from patients with pneumonia (10 strains) or acute bronchitis (2 strains). These strains showed resistance to ML with MICs of >or=1 microg/ml, except to rokitamycin. Transition mutations of A2063G or A2064G, which correspond to A2058 and A2059 in Escherichia coli, in domain V on the 23S rRNA gene in 11 ML-resistant strains were identified. By pulsed-field gel electrophoresis typing, these strains were classified into groups I and IIb [corrected] as described previously (A. Cousin-Allery, A. Charron, B. D. Barbeyrac, G. Fremy, J. S. Jensen, H. Renaudin, and C. Bebear, Epidemiol. Infect. 124:103-111, 2000). These findings suggest that excessive usage of MLs acts as a trigger to select mutations on the corresponding 23S rRNA gene with the resultant occurrence of ML-resistant M. pneumoniae. Monitoring ML susceptibilities for M. pneumoniae is necessary in the future.
authors.affiliation: Laboratory of Infectious Agents Surveillance, Kitasato Institute for Life Sciences, Kitasato University, 5-9-1 Shirokane, Minatoku, Tokyo, 108-8641 Japan.
authors.forename: Miyuki
authors.initials: M
authors.lastname: Morozumi
authors.forename: Keiko
authors.initials: K
authors.lastname: Hasegawa
authors.forename: Reiko
authors.initials: R
authors.lastname: Kobayashi
authors.forename: Nagako
authors.initials: N
authors.lastname: Inoue
authors.forename: Satoshi
authors.initials: S
authors.lastname: Iwata
authors.forename: Haruo
authors.initials: H
authors.lastname: Kuroki
authors.forename: Naohisa
authors.initials: N
authors.lastname: Kawamura
authors.forename: Eiichi
authors.initials: E
authors.lastname: Nakayama
authors.forename: Takeshi
authors.initials: T
authors.lastname: Tajima
authors.forename: Kouichi
authors.initials: K
authors.lastname: Shimizu
authors.forename: Kimiko
authors.initials: K
authors.lastname: Ubukata
mesh_terms: D000293:Adolescent; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002648:Child; D002675:Child, Preschool; D024881:Drug Resistance, Bacterial / Q000235:genetics; D016521:Electrophoresis, Gel, Pulsed-Field; D020459:Genes, rRNA; D006801:Humans; D018942:Macrolides / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests; D009154:Mutation; D009177:Mycoplasma pneumoniae / Q000145:classification / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D011019:Pneumonia, Mycoplasma / Q000382:microbiology; D012338:RNA, Ribosomal, 23S / Q000235:genetics*
chemical_list: D000900:Anti-Bacterial Agents; D018942:Macrolides; D012338:RNA, Ribosomal, 23S