Clinical outcomes of pneumococcal pneumonia caused by antibiotic-resistant strains in Asian countries: a study by the Asian network for surveillance of resistant pathogens

To evaluate the clinical outcomes of pneumococcal pneumonia caused by antibiotic-resistant strains in Asian countries, we performed a prospective observational study of 233 cases of adult pneumococcal pneumonia in 9 Asian countries from January 2000 to June 2001. Among 233 isolates, 128 (55%) were not susceptible to penicillin (25.3% were intermediately susceptible, and 29.6% were resistant). Clinical severity of pneumococcal pneumonia was not significantly different between antibiotic-resistant and antibiotic-susceptible groups. Mortality rates among patients with pneumococcal pneumonia caused by penicillin-, cephalosporin-, or macrolide-resistant strains were not higher than those with antibiotic-susceptible pneumococcal pneumonia. Bacteremia and mechanical ventilation were significant risk factors for death, but any kind of antibiotic resistance was not associated with increased mortality due to pneumococcal pneumonia. Outcome of pneumococcal pneumonia was not significantly affected by drug resistance, and current antimicrobial regimens are mostly effective in the treatment of pneumococcal pneumonia, despite the widespread emergence of in vitro resistance

Macrolide resistance and genotypic characterization of Streptococcus pneumoniae in Asian countries: a study of the Asian Network for Surveillance of Resistant Pathogens (ANSORP)

Objectives: To characterize mechanisms of macrolide resistance among Streptococcus pneumoniae from 10 Asian countries during 1998-2001. Methods: Phenotypic and genotypic characterization of the isolates and their resistance mechanisms. Results: Of 555 isolates studied, 216 (38.9%) were susceptible, 10 (1.8%) were intermediate and 329 (59.3%) were resistant to erythromycin. Vietnam had the highest prevalence of erythromycin resistance (88.3%), followed by Taiwan (87.2%), Korea (85.1%), Hong Kong (76.5%) and China (75.6%). Ribosomal methylation encoded by erm(B) was the most common mechanism of erythromycin resistance in China, Taiwan, Sri Lanka and Korea. In Hong Kong, Singapore, Thailand and Malaysia, efflux encoded by mef(A) was the more common in erythromycin-resistant isolates. In most Asian countries except Hong Kong, Malaysia and Singapore, erm(B) was found in >50% of pneumococcal isolates either alone or in combination with mef(A). The level of erythromycin resistance among pneumococcal isolates in most Asian countries except Thailand and India was very high with MIC90s of >128 mg/L. Molecular epidemiological studies suggest the horizontal transfer of the erm(B) gene and clonal dissemination of resistant strains in the Asian region. Conclusion: Data confirm that macrolide resistance in pneumococci is a serious problem in many Asian countries