No abstract available.
Penicillin Resistance* ; Penicillins* ; Streptococcus pneumoniae* ; Streptococcus*

BACKGROUND: During the last three decades, the resistance of S. pneumoniae to penicillin has been rapidly increasing in many parts of the world, especially in Korea. To characterize the clinical features and epidemiology of penicillin-resistant S. pneumoniae (PRSP) infections in the community and hospital, as well as to investigate the possible spread of resistant clone, we performed the antimicrobial susceptibility tests, pulsed filed gel electrophoresis (PFGE) and penicillin-binding protein (PBP) profile analysis of PRSP isolates. METHODS: A total 48 PRSP isolates from patients who visited or were admitted to Korea University Guro hospital during the period form July 1998 to June 1999 were studied. Anitimicrobial susceptibility tests for 48 isolates were performed with microbroth dilution method to determine the minimal inhibitory concentration of 11 antibiotics. 39 isolates and 35 isolates were subjected to PFGE and PBP profile analysis, respectively to investigate the genetic relatedness between PRSP isolates. RESULTS: Pneumonia was most common site of infection in the community and the hospital as 50%. There were no significant differences of clinical features and prognosis between community and hospital isolates. But, patients with serious underlying diseases had poor prognosis despite of acquisition site. High level penicillin resistance were observed in 69%, multi-drug resistance were 64.6% of isolates. PFGE showed that 13 of 29 community acquired infection were identical PFGE pattern but not that of 23F Spanish clone. There were various PFGE patterns were observed from community and hospital acquired infection isolates. Some of them were existed in both. PBP profiles showed more diverse, even if in isoaltes of the same PFGE pattern. CONCLUSOIN: In our study, high level penicillin resistance and multi-drug resistance were observed in PRSP clinical isolates. No clinical and prognostic differeces were observed between community and hospital acquired infections. Molecular epidemiology study were suggest the there were various genotypes of PRSP within our society. Some of them were observed in the hospital and community. Therefore, there was an evidence of communication of PRSP clones between the community and hospital.
Anti-Bacterial Agents ; Clone Cells ; Drug Resistance, Multiple ; Electrophoresis ; Epidemiology ; Genotype ; Humans ; Korea ; Molecular Epidemiology ; Penicillin Resistance ; Penicillin-Binding Proteins ; Penicillins ; Pneumonia ; Prognosis ; Streptococcus pneumoniae* ; Streptococcus*

PURPOSE: Pneumoccocus is one of the most important causes of invasive infection through the childhood period and the prevelance of antibiotics resistance of pneumococcus is increasing worldwide. A 7-valent conjugate vaccine has been developed. It is important to know the prevalence of each serotype of pneumococci in the countries where the vaccine is used to estimate the coverage rate by the vaccine. METHODS: One hundred and twenty seven strains of clinical isolates and 72 strains from healthy carriers recovered from Korean children during the period from 1997 to 2002 were subjected to determination of serotype by Quellung reaction and penicillin susceptibility with oxacillin disc diffusion test. RESULTS: Forty-three per cent of clinical isolates were obtained from children under two years of age. Thirty strains(24%) were isolated from normally sterile body fluids. The frequent serotypes were 19F, 19A, 23F, 6A, 6B and 9V. Fifty-six per cent of the clinical isolates were represented in the current 7-valent protein conjugate pneumococccal vaccine, and 84% when the cross-reactive serotypes were included. Frequent serotypes of strains isolated from one to five year-old healthy children were 19F, 14, 11A, 23F, 18C, and 19A. Seventy-one per cent of the carrier strains were included in the 7-valent vaccine. Ninety-three per cent of the clinical isolates and 86% of carrier strains were not susceptible to penicilline. CONCLUSION: Fifty-six to 84% of pneumococci recovered from Korean children are covered by the current 7-valent protein conjugate pneumococcal vaccine and the prevalence of penicillin resistance was very high.
Anti-Bacterial Agents ; Body Fluids ; Child* ; Diffusion ; Humans ; Oxacillin ; Penicillin Resistance ; Penicillins* ; Prevalence ; Streptococcus pneumoniae* ; Streptococcus*

BACKGROUND: The incidence of penicillin-resistant streptococcus pneumoniae(PRSP) accounts for almost 70% of all pneumococcal pneumonia cases in Korea. It is still unclear as to whether the efficacy of penicillin or equally active beta-lactam agents is compromised in PRSP pneumonia. This study investigated the prevalence of PRSP in community-acquired pneumonia and its clinical course. METHODS: A total of 42 patients with community-acquired pneumococcal pneumonia were evaluated from July 1999 to May 2001. The cultured strains of Streptococcus pneumoniae were divided into susceptible, intermediately resistant, and resistant strains by an E-test, and the effect of the clinical course was investigated. RESULTS: From a total of 42 patients, 22 (52.4%) patients had an intermediate resistance (MIC 0.1-1 microgram/ml) and six (14.3%) showed a high resistance (MIC> or =2.0 microgram/ml) with current penicillin susceptibility categories. However, according to the classification of the DRSPTWG (Drug Resistant Streptococcus pneumoniae Therapeutic Working Group), there were 11 cases (26.2%) of intermediate resistance and no case of high resistance. Under empirical antimicrobial treatment, there was no difference in the clinical outcome between the penicillin susceptible and resistant group. CONCLUSION: The clinical outcome of PRSP pneumonia with empirical therapy was acceptable. These results suggest that the current MIC breakpoint for penicillin resistance in Streptococcus pneumoniae has been set at a very low level and penicillin resistance according to the NCCLS classification does not significantly influence the outcome of the empirical treatment for pneumococcal pneumonia.
Classification ; Humans ; Incidence ; Korea ; Penicillin Resistance ; Penicillins ; Pneumonia ; Pneumonia, Pneumococcal* ; Prevalence* ; Prognosis ; Streptococcus ; Streptococcus pneumoniae

PURPOSE: The aim of this study was to determine the prevalence of pneumococcal nasal carriage and confirm the distribution of pneumococcal capsular serotypes in Korean children below aged 5 years old. Another reason this study was performed was to identify the theoretical coverage by seven valent conjugate pneumococcal vaccine, and confirm the penicillin resistant rate. METHODS: This study included 213 children, who visited out patient clinic or were hospitalized in six hospitals between August 2001 and April 2002. Nasopharyngeal swabs and cultures for S. pneumoniae were performed. Serotyping of isolated samples was performed by the Quellung reaction at the Statens Seruminstitut in Copenhagen. Penicillin MICs were determined by the agar dilution method, and interpreted according to the NCCLS guide line. RESULTS: The prevalence of pneumococcal nasal carriage rate in this study was 34.3%. A total of 31 of 73 isolates(42.5%) had intermediate resistance to penicillin, and 29 of 73 isolates(39.7%) showed a high resistance to penicillin. The predominant serotype of the S. pneumoniae isolates was 23F(22%), and the percentages of vaccine serotypes(46.6%) and associated serotypes(37%) which belong to the seven-valent pneumococcal conjugate vaccine were 83.6%. The resistance pattern of pneumococcal isolates to penicillin was different among the serotypes. CONCLUSION: Pneumococcal isolates from nasal colonization of Korean children showed a high penicillin resistant rate. We assumed that newly developed seven-valent pneumococcal conjugate vaccine may offer a high theoretical coverage for the isolated strains.
Agar ; Child* ; Child, Preschool ; Colon ; Epidemiologic Studies* ; Humans ; Penicillin Resistance ; Penicillins ; Pneumonia ; Prevalence ; Serotyping

Penicillin resistance in Streptococcus pneumoniae has increased sharply within the past few years and extended-spectrum cephalosporins haute been recommended for the empiric therapy of bacterial meningitis. However, therapeutic failure are being reported with increasing frequency due to extended-spectrum cephalosporin-resistant strains. We report two cases of meningitis caused by S. pneumoniae resistant to penicillin and cefotaxime. Both patients were recovered after ceftriaxone and vancomycin treatment, but one of them was left with neurological sequelae because of a delay in the institution of an antibiotic therapy appropriate for resistant pneumococci. This report indicates that extended-spectrum cephalosporin-resistance must be considered In all clinical isolates of S. pneumoniae and in vitro susceptibility testings should be performed promptly and accurately to detect antibiotic resistance.
Cefotaxime ; Ceftriaxone ; Cephalosporins ; Drug Resistance, Microbial ; Humans ; Meningitis* ; Meningitis, Bacterial ; Penicillin Resistance ; Penicillins ; Pneumonia ; Streptococcus pneumoniae* ; Streptococcus* ; Vancomycin

BACKGROUND: The resistance of Streptococcus pneumoniae to penicillin has been rapidly increasing during the recent three decades. In Korea, we found the incidence of penicillin resistance (PR) to pneumococci was 81% for the clinical isolates in our hospital, and 89% for the colonizing isolates of day-care center around Seoul. Alterations in penicillin-binding protein (PBP) 2B gene have been known to be associated with a resistance to penicillin. We tried to reveal the characteristics of PR of Korean pneumococcal strains through sequencing analysis of PBP 2B gene. METHODS: We determined the nucleotide sequences of 346 bp of a variable region among PBP 2B gene for 12 PR strains and 6 penicillin susceptible (PS) strains isolated in Korea. Phylogenetic tree using PAUP program was made to compare our DNA sequences with those of South African strains. RESULTS: Sequence homology of PS strains was ranged from 99.4% to 100% in Korean PS strain compared to reference strain, R6, except one strain (93.9%). PR strains showed homology of 95.1% to 100% compared to the South African 56762 strain. Phylogenetic analysis based on 346 bp of PBP 2B gene showed that Korean and South African strains formed different monophyletic groups according to the PR/PS patterns. Five specific amino acid changes compared to the PS R6 strain in the position 228, 232, 233, 244, and 261 were noted with a decreased hydrophilicity by Kyte-Doolittle assay. CONCLUSIONS: Our data suggest that the amino acid changes in the PBP 2B are associated with PR in S. pneumoniae, and that a part of Korean PR strains might be originated from a South African PR strain.
Base Sequence ; Colon ; Hydrophobic and Hydrophilic Interactions ; Incidence ; Korea* ; Penicillin Resistance ; Penicillin-Binding Proteins* ; Penicillins ; Pneumonia ; Seoul ; Sequence Homology ; Streptococcus pneumoniae* ; Streptococcus*

BACKGROUND: Resistance to penicillin of Streptococcus pneumoniae in clinical isolates has occurred by the development of altered penicillin-binding proteins (PBPs) that have greatly decreased affinity for antibiotics and has been encountered with increasing frequency in Korea. In this study, the identification of altered PBPs of S. pneumoniae in clinical isolates by using polymerase chain reaction (PCR) and relationship of PCR with the conventional antibiotic susceptibility test of penicillin were evaluated. METHODS: Thirty isolates of S. pneumoniae from clinical specimens were used. Four sets of PCR primers of penicillin-sensitive and -resistant S. pneumoniae were designed to amplify (i) PBP 2BS: a 360 base pair fragment of the PBP 2B gene, (ii) PBP 2BCA: a 350 base pair fragment of the class A mutations present in PBP 2B gene, (iii) PBP 2BCB: a 295 base pair fragment of the class B mutations present in PBP 2B gene, and (iv) PBP 1AR: a 434 base pair fragment of the PBP 1A gene. In addition, a set of primers that amplify 273 base pair of the autolysin gene (ALY) was applied in combination with the above to identify S. pneumoniae. PCR results were compared with antibiotic susceptibility test (disk diffusion test and penicillin MIC). RESULT: Among 30 clinical isolates tested, 80% of isolates were penicillin resistant. The results of antibiotic susceptibility test were same as those of PCR methods. Among 24 penicillin resistant isolates detected by PCR methods, 5 isolates revealed PBP 2BCB gene, but 19 isolates revealed both of PBP 2BCB and 1AR genes. Five isolates with PBP 2BCB gene showed lower range of penicillin MIC (0.19 ~ 1.0 g/mL) than 19 isolates with PBP 2BCB and 1AR genes (0.75 ~ 4.0 g/mL). CONCLUSION: Detection of altered PBP genes of S. pneumoniae by PCR may be performed for the study of penicillin resistance. This study indicates that more altered PBPs in 1AR genes are related with higher MICs.
Anti-Bacterial Agents ; Base Pairing ; Diffusion ; Korea ; N-Acetylmuramoyl-L-alanine Amidase ; Penicillin Resistance ; Penicillin-Binding Proteins ; Penicillins ; Pneumonia ; Polymerase Chain Reaction* ; Streptococcus pneumoniae* ; Streptococcus*

BACKGROUND: Pneumococcus is the most common cause of acute otitis media, community acquired pneumonia and invasive bacterial diseases in children. Ninety serotypes have been identified, and the distribution differs according to geographic area and ages. The 7 valent pneumococcal protein conjugate vaccine is used widely. To evaluate the efficacy of the vaccine, it is essential to investigate the distribution of the pneumococcal serotypes. MATERIALS AND METHODS: The serotypes and antibiotic resistance of the pneumococcus isolated from 308 patients at Shinchon Severance hospital from September of 2001 to July of 2005 were analyzed. RESULTS: The pneumococcci were isolated mostly from sputum and blood, and ear discharge in the descending order. Serotyping was possible in 265 cases, and the distribution of serotypes were 19F (16.2%), 19A (12.8%), 23F (8.7%), 6B (7.9%), and 6A (7.2%). Fifty two cases were isolated from those patients less than 16 years of age and the distribution of serotypes was 19F, 19A, 23F, 14, 6B, 6A and 4. Resistance to penicillin was 64.6% in all cases and 67.3% in children. The more common serotype showed the higher rate of penicillin resistance. Multi-drug resistance was demonstrated in 64.7%. Forty three percent of the total identified serotypes were included in the 7 valent pneumococcal conjugate vaccine. And 61.5% of the serotypes identified in children were included in the vaccine. CONCLUSION: The 7 valent vaccine may be used effetively in Korea. But, further study is needed to address serotype switching after the use of the protein conjugated vaccine, which has been reported in other countries.
Anti-Bacterial Agents ; Child ; Drug Resistance, Microbial ; Drug Resistance, Multiple ; Ear ; Humans ; Korea ; Otitis Media ; Penicillin Resistance ; Penicillins ; Pneumonia ; Serotyping ; Sputum ; Streptococcus pneumoniae* ; Streptococcus*

BACKGROUND: Pneumococcus is the most common cause of acute otitis media, community acquired pneumonia and invasive bacterial diseases in children. Ninety serotypes have been identified, and the distribution differs according to geographic area and ages. The 7 valent pneumococcal protein conjugate vaccine is used widely. To evaluate the efficacy of the vaccine, it is essential to investigate the distribution of the pneumococcal serotypes. MATERIALS AND METHODS: The serotypes and antibiotic resistance of the pneumococcus isolated from 308 patients at Shinchon Severance hospital from September of 2001 to July of 2005 were analyzed. RESULTS: The pneumococcci were isolated mostly from sputum and blood, and ear discharge in the descending order. Serotyping was possible in 265 cases, and the distribution of serotypes were 19F (16.2%), 19A (12.8%), 23F (8.7%), 6B (7.9%), and 6A (7.2%). Fifty two cases were isolated from those patients less than 16 years of age and the distribution of serotypes was 19F, 19A, 23F, 14, 6B, 6A and 4. Resistance to penicillin was 64.6% in all cases and 67.3% in children. The more common serotype showed the higher rate of penicillin resistance. Multi-drug resistance was demonstrated in 64.7%. Forty three percent of the total identified serotypes were included in the 7 valent pneumococcal conjugate vaccine. And 61.5% of the serotypes identified in children were included in the vaccine. CONCLUSION: The 7 valent vaccine may be used effetively in Korea. But, further study is needed to address serotype switching after the use of the protein conjugated vaccine, which has been reported in other countries.
Anti-Bacterial Agents ; Child ; Drug Resistance, Microbial ; Drug Resistance, Multiple ; Ear ; Humans ; Korea ; Otitis Media ; Penicillin Resistance ; Penicillins ; Pneumonia ; Serotyping ; Sputum ; Streptococcus pneumoniae* ; Streptococcus*