Clinical Evaluation of Macrolide-Resistant Mycoplasma pneumoniae

Abstract

Macrolide-resistant Mycoplasma pneumoniae (MR M. pneumoniae) has been isolated from clinical specimens in Japan since 2000. A comparative study was carried out to determine whether or not macrolides are effective in treating patients infected with MR M. pneumoniae. The clinical courses of 11 patients with MR M. pneumoniae infection (MR patients) treated with macrolides were compared with those of 26 patients with macrolide-susceptible M. pneumoniae infection (MS patients). The total febrile days and the number of febrile days during macrolide administration were longer in the MR patients than in the MS patients (median of 8 days versus median of 5 days [P ‫؍‬ 0.019] and 3 days versus 1 day [P ‫؍‬ 0.002], respectively). In addition, the MR patients were more likely than the MS patients to have had a change of the initially prescribed macrolide to another antimicrobial agent (63.6% versus 3.8%; odds ratio, 43.8; P < 0.001), which might reflect the pediatrician's judgment that the initially prescribed macrolide was not sufficiently effective in these patients. Despite the fact that the febrile period was prolonged in MR patients given macrolides, the fever resolved even when the initial prescription was not changed. These results show that macrolides are certainly less effective in MR patients.Mycoplasma pneumoniae is a common pathogen causing community-acquired respiratory tract infection mainly in children and young adults. Macrolides are generally considered to be the first-choice agents for treatment of M. pneumoniae infection. Although tetracyclines and fluoroquinolones are effective against M. pneumoniae, these agents are not recommended for children because of their toxicity. Tetracyclines can cause depression of bone growth, permanent gray-brown discoloration of the teeth, and enamel hypoplasia when given during tooth development. Although the clinical importance of fluoroquinolones has not been demonstrated, they produce cartilage erosion in young animals. Thus, these agents should be given only when there is no alternative (15).As reported by Lucier et al. (9) and Okazaki et al. (14), an A-to-G transition or A-to-C transversion at position 2063 or 2064 of domain V of the M. pneumoniae 23S rRNA gene results in resistance to macrolide antibiotics. We have previously reported the isolation of macrolide-resistant (MR) M. pneumoniae from ca. 20% of clinical specimens collected from pediatric patients in Japan (11). Most of those isolates were highly resistant to 14-membered ring macrolides (MIC, Ͼ256 g/ml) and moderately resistant to 15-and 16-membered ring macrolides.Even in the cases of patients infected with MR M. pneumoniae, some pediatricians had the impression that there was a good response to macrolide therapy (11). There is a similar debate about the management of infection due to pneumococci. As noted in The Infectious Diseases Society of America (IDSA) guidelines for community-acquired pneumonia management (10), despite the increase of resistant isolates, a corresponding increase has not been seen in...

Azithromycin treatment failure in macrolide-resistantMycoplasma pneumoniaepneumonia: Figure 1–

“…Despite numerous reports of detection of macrolide-resistant M. pneumoniae from clinical specimens, there have been few studies on the clinical impact of resistant strains. Children infected with macrolide-resistant M. pneumoniae have a longer duration of fever after initiating macrolide therapy than those infected with a macrolidesensitive strain, and macrolide was more likely to change to another antimicrobial [8]. However, in the study by SUZUKI et al [8], patients infected with macrolide-resistant strains were more likely to receive erythromycin or clarithromycin than azithromycin.…”

Regional Differences in Prevalence of Macrolide Resistance among Pediatric <i>Mycoplasma pneumoniae</i> Infections in Hokkaido, Japan

“…The rate of macrolide resistance among M. pneumoniae infections ranges from 3 to 26z in Europe (9,15), from 63 to 97z in China (16)(17)(18)(19), and from 25 to 93z in Japan (20)(21)(22). The total number of febrile days and the number of febrile days during macrolide administration are greater in patients infected with MR M. pneumoniae than in patients infected with macrolide-sensitive (MS) M. pneumoniae (23). Therefore, it is important to understand the regional prevalence of MR M. pneumoniae infections to predict the duration of fever caused by M. pneumoniae.…”

In Vitro Activities of 11 Antimicrobial Agents against Macrolide-Resistant Mycoplasma pneumoniae Isolates from Pediatric Patients: Results from a Multicenter Surveillance Study

“…Several studies indicated that macrolide resistance in M. pneumoniae may have clinical significance in terms of diminished response to treatment with drugs in this class (2,12,13). In Japan, reports of macrolide-resistant M. pneumoniae were from limited areas, and there have been no large-scale epidemiological studies conducted throughout Japan.…”