The in vitro antibacterial activities of oral cephem antibiotics and ketolide telithromycin against major respiratory pathogens possessing beta-lactam-resistant mutations (within the pbp gene) and/or macrolide-resistant genes (erm and mef) were examined in clinical isolates collected at 66 institutes in all over the Japan between 2002 and 2003. Telithromycin showed the strongest antibacterial activity against methicillinsusceptible Staphylococcus aureus strains with and without macrolide-resistant genes, such as ermA or ermC gene. All the cephem antibiotics showed potent antibacterial activity against Streptococcus pyogenes, with minimum inhibitory concentrations (MICs) of 0.015 mg/L or lower. Cefdinir had a much higher MIC90 against genotypic penicillin-resistant Streptococcus pneumoniae (gPRSP) than cefditoren and cefcapene (8 mg/L cefdinir vs. 1 mg/L cefditoren and cefcapene). The majority of gPRSP harbored either ermB or mefA, and the antibacterial activity of telithromycin against these strains was decreased however some susceptibility was still sustained. Cefditoren exerted the strongest antibacterial activity against beta-lactamase-negative ampicillin-resistant Haemophilus influenzae, with an MIC90 of 0.5 mg/L. These results underline the importance of checking the susceptibility and selecting an appropriate antibiotic against target pathogens.
Streptococcus pyogenes/*drug effects ; Streptococcus pneumoniae/*drug effects ; Staphylococcus aureus/*drug effects ; Microbial Sensitivity Tests ; Methicillin Resistance ; Ketolides/*pharmacology ; Humans ; Haemophilus influenzae/*drug effects ; Cephalosporins/*pharmacology ; Administration, Oral

OBJECTIVETo investigate the antimicrobial resistance of Streptococcus pneumoniae (S.pneumoniae) isolated from Chinese children with pneumonia.

METHODSHypopharyngeal aspirate specimens were collected from hospitalized children with pneumonia who were admitted to the children's hospital located in Beijing, Shanghai, Guangzhou or Shanghai from February 16, 2006 to February 16, 2007. The minimum inhibitory concentration (MIC) of S.pneumoniae isolates against penicillin, amoxicillin, cefuroxime (sodium), ceftriaxone, erythromycin, vancomycin, ofloxacin and imipenem was determined by E-test method.

RESULTSA total of 279 S.pneumoniae isolates were obtained. Eighty-six percent of the isolates were not susceptive to penicillin, and 23.3% was resistant to penicillin. The rate of susceptibility of the isolates to amoxicillin was 92.1%, and to cefuroxime and ceftriaxone was 19.0% and 75.3%, respectively. The isolates also showed a high susceptibility to vancomycin (99.6%) and ofloxacin (97.8%). Seventeen point six percent of the isolates were not susceptive to imipenem, and most of those were intermediate. Almost of all isolates were resistant to erythromycin. There were some distinct regional differences in the susceptibility to antimicrobials tested except for erythromycin, vancomycin and ofloxacin.

CONCLUSIONSThe S.pneumoniae isolates from Chinese children with pneumonia were susceptive to amoxicillin, vancomycin and ofloxacin, but were not susceptive or resistant to penicillin, cefuroxime and erythromycin. The isolates kept susceptibility to ceftriaxone and imipenem to a certain extent.

Child ; Drug Resistance, Bacterial ; Hospitalization ; Humans ; Microbial Sensitivity Tests ; Streptococcus pneumoniae ; drug effects

Background: Acute lower respiratory tract infection, mainly pneumonia, were the main reasons cause death for children under 5 years old. Objectives: Determine the isolated rate of bacteria inpatients under 5 years old with acute lower respiratory tract infection in Ha Noi and antibiotic resistance of pneumococcal isolated form patients. Subjects and method: Patients under 5 years old with acute lower respiratory tract infection in National hospital of pediatrics and Bach Mai hospital from 01/2002. Using quantitative culturedand PCR method. Results: Out of total 164 patients with lower respiratory tract infection, there were 91 diagnosed pneumonia by chest X-ray, 73 cases of acute bronchitis. 73,6% of the pneumococcal isolated were penicillin resistance (gPRSP) with different genes such as pbp 1a+2x+ab. Most of the S.pneumoniae strains were serotype 19F or 23F. There were no statistic differences by comparison charactersistics of weight, vessel, subclinical symptoms such as: dissolved oxygen level (S\xac\xacp\xac\xac\xac\xacO\xac2\xac), the amount of leucocyte in blood. However, temperature of pneumonia patients was higher than bronchitis patients, breathing of pneumonia patients was also faster than bronchitis patients. Isolated bacteria with amount \ufffd?106 cfu/ml was H.influenzae, S.pneumoniae and Moraxell catarrhalis in pneumonia group, bronchitis group was 28,8% and control group was 17,1%. Conclusion: Penicillin, erythoromycin and co-trimoxazole resistance rate of S.pneumoniaein patients with acute lower respiratory tract infection was high. Quantitative cultured method has prognostic value in diagnosis pneumonia.
Genes ; MDR/ drug effects ; immunology ; Streptococcus pneumoniae/ growth & ; development ; Anti-Bacterial Agents

Bacteria ; drug effects ; isolation & purification ; Drug Resistance ; Escherichia coli ; drug effects ; Female ; Haemophilus influenzae ; drug effects ; Humans ; Klebsiella pneumoniae ; drug effects ; Male ; Microbial Sensitivity Tests ; Respiratory Tract Infections ; microbiology ; Staphylococcus aureus ; drug effects ; Streptococcus pneumoniae ; drug effects

OBJECTIVETo investigate the antimicrobial resistance of invasive and non-invasive Streptococcus pneumoniae (SP) strains in children and to provide a basis for proper use of antimicrobial drugs in the treatment of SP infection.

METHODSSeventy children who were diagnosed with invasive pneumococcal diseases (IPD) between January 2009 and December 2013 were enrolled, and 164 children with lower respiratory tract infection caused by SP were randomly selected as the control group. The samples from sterile sites (blood, cerebrospinal fluid, etc) of children with IPD, as well as the sputum samples of children in the control group, were collected for bacterial culture, and the drug susceptibility tests for isolated SP strains were conducted.

RESULTSA total of 82 invasive strains of SP were isolated from sterile sites of 70 children with IPD; 49 strains (60%) were isolated from blood, and 19 strains (23%) from cerebrospinal fluid. The detection rate of invasive SP strains decreased from 2009 to 2013 (P<0.01). The total detection rates of penicillin-nonsusceptible SP from the invasive and non-invasive strains were 27% and 17% respectively (P>0.05). Among invasive strains, the penicillin-nonsusceptible SP strains had significantly higher rates of insusceptibility to cefotaxime, ceftriaxone, and cefepime than the penicillin-susceptible SP (P<0.01). There were significant differences in the rates of insusceptibility to cefotaxime, ceftriaxone, and meropenem between the sensitive and non-sensitive SP strains (P<0.05). The multidrug resistance rates of the invasive and non-invasive SP strains were 89% and 93% respectively (P>0.05).

CONCLUSIONSInvasive SP can easily invade the blood in children, but the total detection rate has decreased year by year. The results of drug sensitivity tests have guiding significance for proper use of antimicrobial drugs for different SP infections.

Adolescent ; Child ; Child, Preschool ; Drug Resistance, Bacterial ; Female ; Humans ; Infant ; Infant, Newborn ; Male ; Streptococcus pneumoniae ; drug effects

OBJECTIVEStreptococcus pneumoniae (SP) is a major causative agent of community-acquired pneumonia. In children older than 2 months, SP is also the most common cause of invasive bacterial infections. Invasive pneumococcal diseases (IPD) have become a severe problem of public health worldwide. The aim of this study was to summarize the clinical characteristics and antimicrobial resistance of IPD in children, and to raise the level of diagnosis and treatment of this disease.

METHODThe clinical data from 55 cases of IPD younger than 12 years old seen from January 2004 to June 2009 in Yuying Children's Hospital Affiliated to Wenzhou Medical College were analyzed retrospectively. Blood, cerebrospinal fluid (CSF), seroperitoneum, mediastinum and soft tissue aspirate specimens were collected from these children, and 64 SP strains were cultured, isolated and confirmed and the antibiotics susceptibility to penicillin and other antibiotics of these strains were assessed.

RESULTThe 55 cases of IPD were identified, among whom 32 were male and 23 female, the ratio was 1.39. The ages ranged from 47 days to 12 years. Most (62%) of the cases were aged less than 2 years, and 16% were aged from 2 to 5 years. Overall, 38 (69%) had septicemia, of whom 8 cases were complicated with meningitis, 2 with pneumonia complicated with empyema, 1 had pneumonia complicated with mediastinal abscess and 11 with pneumonia. Nine cases (16%) were diagnosed as meningitis. Seven cases (13%) had hip or neck abscess and 1 case had purulent peritonitis. Thirteen cases (24%) had an underlying disease, including mainly leukemia (31%), followed by congenital heart disease (23%) and head trauma (15%). Three cases (5%) had received a surgical operation; 3 cases (5%) had combined virus infections and 2 cases (4%) had mycoplasma infection. Most (73%) episodes occurred in winter and spring. The main origin of infection was community (89%). Forty of the patients were cured, 12 improved and 3 died (5%). Nine cases (16%) developed neurologic complications. There was a statistically significant differences in the annual detection rate of invasive SP (chi(2) = 33.93, P < 0.01). The incidence of penicillin-intermediate S. pneumoniae (PISP) and penicillin-resistant S. pneumoniae (PRSP) were 30% and 41%, respectively; the resistance to erythromycin and lincomycin were found in as high as 94% and 88% of isolates, respectively; while the resistant rate to chloramphenicol and cefotaxime were low, 26% and 22%, respectively. The multidrug resistance rate was 89%.

CONCLUSIONChildren aged less than 5 years, especially younger than 2 years are prone to IPD and the underlying diseases are found in 24% of cases; septicemia and meningitis are the common diseases.

Child ; Child, Preschool ; Drug Resistance, Bacterial ; Female ; Humans ; Infant ; Male ; Pneumonia, Pneumococcal ; diagnosis ; microbiology ; Retrospective Studies ; Streptococcus pneumoniae ; drug effects

AIMTo synthesizs of derivatives of (9S)-12-methylene erythromycin possessed potent antibacterial activity.

METHODSUsing erythromycin A as a starting material, via two intermediate compounds protected 12,21-dehydroerythromycin A and 6,7: 12,21-didehydro erythromycin A, several 9-O, 11-O-ethylidene compounds were obtained. During this process, benzyl and isopropyl have been selected as the protecting group. The structures of compounds obtained were confirmed with 13C NMR and MS-FAB. Their antibacterial activity in vitro was tested.

RESULTSEleven derivatives of erythromycin were synthesized. Five of them were unknown compounds.

CONCLUSIONThe preliminary biological test showed that two target compounds exhibited less potent antibacterial activity in vitro.

Anti-Bacterial Agents ; chemical synthesis ; pharmacology ; Erythromycin ; analogs & derivatives ; chemical synthesis ; pharmacology ; Microbial Sensitivity Tests ; Staphylococcus aureus ; drug effects ; Staphylococcus epidermidis ; Streptococcus pneumoniae ; drug effects

OBJECTIVETo study the clinical characteristics of children with meningitis caused by Streptococcus pneumoniae (SP) and the drug sensitivity of SP strains.

METHODSA retrospective analysis was performed on the clinical data of 14 children with SP-infected meningitis between September 2008 and March 2014.

RESULTSOf the 14 cases, 8 cases (57%) aged under 2 years. 13 cases (93%) had fever, 9 cases (64%) had convulsions, and 7 cases (50%) were complicated by septicemia. Eleven cases (79%) had elevated white blood cell (WBC) counts and 10 cases (71%) had elevated serum C-reactive protein (CRP) levels. All 14 children had an elevated nucleated cell count and neutrophils were identified as the predominant cell type. CSF protein>1000 mg/dL was noted in 9 cases (64%). Ten cases (71%) were cured, 2 cases (14.2%) with sequelae and 2 cases (14.2%) died. The drug sensitivity analysis showed that SP had resistance rates of more than 60% to penicillin, erythromycin, clindamycin, tetracycline and sulfa, but it was sensitive to amoxicillin (93%), vancomycin (100%), chloramphenicol (100%) and levofloxacin (100%).

CONCLUSIONSThe clinical characteristics of children with meningitis caused by SP are not different from those with meningitis caused by other bacteria. SP strains are resistant to common antibiotics used in clinical practice, so it is important to monitor the drug resistance of the strains.

Adolescent ; Child ; Child, Preschool ; Drug Resistance, Microbial ; Female ; Humans ; Infant ; Male ; Meningitis, Pneumococcal ; drug therapy ; Retrospective Studies ; Streptococcus pneumoniae ; drug effects

OBJECTIVEThe present study was designed to investigate the situation of serotype distribution and beta-lactam antibiotics resistance of Streptococcus pneumoniae (S. pneumoniae) isolated from Chinese children, and to further understand the significance of vaccine for preventing infection caused by the bactria and controlling the resistance to antibiotics.

METHODSNasopharageal swab specimens were collected from randomly selected less than 5-year-old out-patients with upper respiratory infection in Beijing, Shanghai and Guangzhou, 2000 - 2002. Capsular typing was performed by the Quellung reaction tested using a simplified chessboard system for typing of S. pneumoniae. The coverage rate of the 7-valent pneumococcal conjugate vaccine (4, 6B, 9V, 14, 18C, 19F and 23F) was calculated. Antibiotic susceptibility was determined by E-test MIC method for beta-lactam antibiotics (penicillin, amoxicillin/clavulanic acid, cefaclor, cefuroxime and ceftriaxone).

RESULTSTotally 625 pneumococcal strains were typed. Serogroup 19, including 121 strains, was the most frequent serogroup observed (19.4%). Other frequently observed serotypes/serogroups in decreasing order of frequency were serotype/serogroups 23 (15.4%), 6 (13.3%), 14 (6.6%) and 15 (4.3%). Of all these isolates, about 57.6% (360/625) were in the 7-valent conjugate vaccine. Only 1, 6 and 12 strains were serotypes/serogroups 4, 9 and 18, respectively. The coverage rate for the 7-valent vaccine of penicillin nonsusceptible S. pneumoniae (PNSP) was higher than penicillin susceptible S. pneumoniae (PSSP) (73.2% and 46.1%). Serogroups 19 and 23, without other serotypes/serogroups, were significantly associated with PNSP (serogroup 19 accounted for 29.1% of PNSP and 12.2% of PSSP; serogroup 23 accounted for 23.8% of PNSP to 9.2% of PSSP). Overall, 140 strains (22.4%) could not be typed by using the chessboard system, and 117 strains (18.7%) were identified as other 28 kinds of serotype/serogroup. The strains showed different resistance change for beta-lactam antibiotics according to different serotype/serogroup during the three years.

CONCLUSIONSSerotype/Serogroup 19, 23, 6, 14 and 15 were the common types among the pneumococcal strains isolated from Chinese children. Serogroups 19 and 23 were significantly associated with PNSP. The 7-valent pneumococcal conjugate vaccine could cover most of the islotes.

Child, Preschool ; China ; epidemiology ; Drug Resistance, Multiple, Bacterial ; Humans ; Pneumococcal Infections ; epidemiology ; Respiratory Tract Infections ; epidemiology ; microbiology ; Serotyping ; Streptococcus pneumoniae ; classification ; drug effects

Penicillin-binding proteins (PBPs) are the target of β-lactam antibiotics (the major treatment for Streptococcus pneumoniae infections), and mutations in PBPs are considered as a primary mechanism for the development of β-lactam resistance in S. pneumoniae. This study was conducted to investigate the mutations in the PBPs of clinical S. pneumoniae isolates in Hangzhou, China, in correlation with β-lactam resistance. Results showed that 19F was the predominant serotype (7/27) and 14 of the S. pneumoniae isolates were resistant to both penicillin G and cephalosporin. Genotyping results suggested that β-lactam-resistant isolates primarily exhibited single-site mutations in both the STMK and SRNVP motifs of pbp1a in combination with double-site mutations in the STMK motif of pbp2x, which might be the primary mechanisms underlying the β-lactam resistance of the isolates in this study.
Anti-Bacterial Agents ; pharmacology ; China ; epidemiology ; Drug Resistance, Bacterial ; Humans ; Pneumococcal Infections ; epidemiology ; microbiology ; Streptococcus pneumoniae ; drug effects ; genetics ; beta-Lactams ; pharmacology