Antimicrobial susceptibility and serotype distribution of Streptococcus pneumoniae isolated from patients with community-acquired pneumonia and molecular analysis of multidrug-resistant serotype 19F and 23F strains in Japan

Abstract

A nationwide study was undertaken to determine the susceptibility to penicillin and serotypes of Streptococcus pneumoniae in Japan. S. pneumoniae was isolated from 114 adult patients with community-acquired pneumonia over 22 months at 20 hospitals and medical centres in different regions in Japan. All but five isolates were from sputum. Forty-eight isolates (42·1%) were susceptible, 40 (35·1%) showed intermediate resistance (MIC, 0·12–1·0 μg/ml) and 26 (22·8%) were resistant (MIC, [ges ]2·0 μg/ml) to penicillin G. All isolates were susceptible to ceftriaxone (breakpoint 1 μg/ml), imipenem (4 μg/ml) and vancomycin (4 μg/ml). Most were resistant to erythromycin, clarithromycin and azithromycin; only two were resistant to levofloxacin. Differences were found in the distribution of serotypes among isolates showing susceptibility to penicillin (predominant types 3, 6B, and 19F), intermediate resistance (6B, 14, 19F, and 23F) and full resistance (19F and 23F). PFGE typing showed that 14 of the 25 strains of serotype 19F had a single DNA profile, pattern A, a pattern closely similar to that of the Taiwan multidrug-resistant 19F clone. Twelve pattern A strains were not susceptible to penicillin but carried the macrolide resistance gene mef(A). The DNA profiles of the 15 strains of 23F were also heterogeneous but six were highly similar (pattern b) yet distinct from the Spanish multidrug-resistant 23F clone although possibly related to the Taiwan multidrug-resistant 23F clone. The pattern b strains were not susceptible to penicillin and also harboured either mef(A) or erm(B). Our results indicate that multidrug-resistant pneumococci are spreading rapidly in Japan. Efforts to prevent the spread of the pandemic multidrug-resistant serotypes should be intensified.

Antimicrobial Susceptibility and Genetic Characteristics of Streptococcus pneumoniae Isolates Indicating Possible Nosocomial Transmission Routes in a Community Hospital in Japan

“…In this study, we found that 72.6% and 83.3% of all strains were not susceptible to penicillin and macrolides, respectively, numbers that were very close to the findings of previous studies (14,30). One possible cause of the increase in drug resistance is long-term antimicrobial therapy (15).…”

Serotype Replacement in Adult Pneumococcal Pneumonia after the Introduction of Seven-Valent Pneumococcal Conjugate Vaccines for Children in Japan: a Systematic Literature Review and Pooled Data Analysis

“…Using 5 major databases, we comprehensively conducted systematic literature survey to identify studies that reported on the serotype distribution of adult pneumococcal pneumonia. In our pooled data analysis of the 4 studies (1,(17)(18)(19), the proportion of PCV7-covered serotypes decreased significantly and the proportions of serotypes of PCV13-PCV7, PPV23-PCV7, PPV23-PCV13, and non-VTs increased significantly. In summary, the decrease of the proportion of PCV7-covered serotype led to the increase of the proportion of non-PCV7-covered strains.…”

“…All of the studies were performed in the pre-PCV13 period. The study designs could be categorized into case series of pneumococcal LRTI (15,16), prospective surveillance of pneumococcal LRTI or IPD cases (1,(17)(18)(19)(20), and laboratory-based pneumococcal strain surveillance (21)(22)(23)(24)(25)(26)(27)(28)(29)(30)(31)(32)(33)(34)(35). One of the prospective surveillance studies of the LRTI referred to the Japanese Respiratory Society (JRS) guidelines for the management of community-acquired pneumonia in adults (36) as diagnostic criteria for LRTI (17).…”

“…One of the prospective surveillance studies of the LRTI referred to the Japanese Respiratory Society (JRS) guidelines for the management of community-acquired pneumonia in adults (36) as diagnostic criteria for LRTI (17). Another 3 prospective surveillance studies of pneumonia also used similar case definitions to the JRS guidelines (1,18,19). All the laboratory-based pneumococcal strain surveillance studies were designed to test the collected pneumococcal strains from various specimens such as sputum, respiratory tract aspirates, nasopharyngeal swabs, eye or ear discharge, blood, cerebrospinal fluid, and pleural fluid.…”

Efficacy of Azithromycin in the Treatment of Community-acquired Pneumonia, Including Patients with Macrolide-Resistant Streptococcus pneumoniae Infection

“…In recent years, there has been an increasing worldwide problem of drug resistance among respiratory pathogens, notably S. pneumoniae which has shown increasing levels of penicillin and macrolide resistance (10)(11)(12)(13) (1,6,7). Resistance to macrolides among strains of S. pneumoniae is caused by two principal mechanisms: 1) methylation of a ribosomal binding site, which is encoded by the ermB gene; and 2) active drug efflux via a cell membrane protein transporters, which is encoded by the mefA gene (14).…”