Vol.62 No.1 January 2014
Nationwide surveillance and therapeutic efficacy of antimicrobial agents against macrolide-resistant Mycoplasma pneumoniae infection in pediatric patients
Department of Pediatrics, Kawasaki Medical School, 577 Matsushima, Kurashiki, Okayama, Japan
Abstract
Mycoplasma pneumoniae is a common causative pathogen of respiratory tract infections in children and young adults. During 2010 and 2012, epidemics of M. pneumoniae infection, especially among children, occurred throughout Japan, and the incidences were the highest that had been observed in the previous decade. For the treatment of M. pneumoniae, which, unlike most other types of bacteria, has no cell wall, protein synthesis inhibitors such as macrolides or tetracyclines or DNA synthesis inhibitors such as quinolones are used in adults. Macrolides are generally considered to be the first-choice agents for the treatment of M. pneumoniae infection in pediatric patients. In 2000, however, M. pneumoniae strains showing resistance to macrolides were isolated from clinical samples obtained from Japanese pediatric patients with pneumonia, and macrolide resistance has become widespread in Japan. Macrolide-resistant (MR)M. pneumoniae is also emerging in pediatric populations in other countries. However, data on MR M. pneumoniae have mostly been reported for limited areas, and there are no reports on regional differences in the prevalence of MR M. pneumoniae throughout Japan. We conducted nationwide surveillance to investigate regional differences in macrolide-resistant (MR)Mycoplasma pneumoniae strains in Japan. The prevalence of MR M. pneumoniae in pediatric patients gradually increased between 2008 and 2012. Although regional differences were observed, high levels of MR genes were detected in all seven surveillance areas throughout Japan and ranged in prevalence from 50% to 93%. These regional differences were closely related to the previous administration of macrolides.
Of these, 150 patients had a strain with an MR gene and 134 had one with an A-to-G mutation at position 2063 of M. pneumoniae 23S rRNA domain V. Azithromycin (n=27), clarithromycin (n=23), tosufloxacin (n=62), or minocycline (n=38) was used for definitive treatment of patients with MR M. pneumoniae. Defervescence within 48 h after the initiation of antibiotic therapy was observed in 41% of the patients in the azithromycin group, 48% of those in the clarithromycin group, 69% of those in the tosufloxacin group, and 87% of those in the minocycline group. The average number of days of fever after the administration of antibiotic treatment was lower in the minocycline and tosufloxacin groups than in the macrolide groups. The decrease in the M. pneumoniae burden, as estimated by the number of DNA copies, after 48 to 96 h of treatment was more rapid in patients receiving minocycline (p=0.016) than in those receiving tosufloxacin (p=0.049), azithromycin (p=0.273), or clarithromycin (p=0.107). We found that the clinical and bacteriological efficacies of macrolides against MR M. pneumoniae pneumonia was low. Our results indicated that minocycline rather than tosufloxacin can be considered the first-choice drug for the treatment of M. pneumoniae pneumonia in children aged>8 years.
Key word
macrolide-resistant Mycoplasma pneumoniae, child, community-acquired pneumonia, epidemiology
Received
August 27, 2013
Accepted
December 12, 2013
Jpn. J. Chemother. 62 (1): 110-117, 2014
