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• The first culture-confirmed pediatric IMD case caused by Y:cc23 in China. • The increase of NmY isolates warranting the wider usage of MPC-ACYW vaccine in China. • The Chinese cc23 isolates with phenotypically resistance to penicillin or quinolones. • Identification of the global dissemination of the three cc23 sub-lineage. Serogroup Y Neisseria meningitidis (NmY) is rare in China, and only serogroup A and C meningococcal polysaccharide vaccines (MPVs) are included in the national vaccination schedule. We describe a case of fulminant meningococcemia caused by NmY, which occurred in a pediatric patient (2 years old) for the first time in China, confirmed by culture. Although the boy was treated in time, the dry gangrene in his toes and fingers left him with severe sequelae. An NmY isolate was cultured from the blood of the patient, and showed decreased susceptibility to penicillin (minimum inhibitory concentration of 0.125 μg/ml), with sequence type (ST) 1655 assigned to clonal complex (cc) 23. Genomic analysis showed it was clustered with isolates from Italy, UK, Finland, and South Africa, sharing designation of Y:P1.5–1,10–1:F4-1:ST-1655(cc23). The emergence of NmY invasive meningococcal disease cases challenges local immunization strategy and warrants wider usage of MPV-ACYW if there is sustained circulation of NmY. [ABSTRACT FROM AUTHOR]

Invasive meningococcal disease (IMD) due to serogroup Y Neisseria meningitidis (NmY) is rare in China; recently, an invasive NmY isolate, Nm512, was discovered in Shanghai with decreased susceptibility to penicillin (Pen NS ). Here, we investigated the epidemiology of NmY isolates in Shanghai and explored the potential commensal Neisseria lactamica donor of the Pen NS NmY isolate. A total of 491 N. meningitidis and 724 commensal Neisseria spp. isolates were collected. Eleven NmY isolates were discovered from IMD ( n  = 1) and carriers ( n  = 10), including two Pen NS isolates with five-key-mutation-harboring (F504L-A510V-I515V-H541N-I566V) penA genes. Five of the eight ST-175 complex (CC175) isolates had a genotype [Y:P1.5-1,2-2:F5-8:ST-175(CC175)] identical to that of the predominant invasive clone found in South Africa. Only one invasive NmY CC23 isolate (Nm512) was discovered; this isolate carried a novel Pen NS penA832 allele, which was identified in commensal N. lactamica isolates locally. Recombination analysis and transformation of the penA allele highlighted that N. meningitidis Nm512 may acquire resistance from its commensal donor; this was supported by the similar distribution of transformation-required DNA uptake sequence variants and the highly cognate receptor ComP between N. meningitidis and N. lactamica. In 2,309 NmY CC23 genomes from the PubMLST database, isolates with key-mutation-harboring penA genes comprised 12% and have been increasing since the 1990s, accompanied by recruitment of the bla ROB-1 and/or quinolone resistance allele. Moreover, penA22 -harboring CC23 isolate from Europe and acquired its penicillin resistance locally from commensal N. lactamica species by natural transformation.penA . These results strongly suggest that Nm512 is a descendant of the penA22 -harboring CC23 isolate from Europe and acquired its penicillin resistance locally from commensal N. lactamica species by natural transformation.

Aim: To find a quick and reliable diagnostic technique for penicillin nonsusceptible Streptococcus pneumoniae (PNSSP) from Nanjing, China. Methods and Results: A total of 130 S. pneumoniae clinical isolates and 50 healthy carriers’ isolates were collected from seven teaching hospitals in Nanjing between March 2005 and June 2007. Three different methods, PCR, seminested-PCR, and PCR-RFLP, were applied in detecting PNSSP. The prevalence of PNSSP was 73·9%, the penicillin-resistance rate of children’s group and adults’ group were 87·8% and 31·2%, respectively. The PCR method had difficulty in identifying intermediate-resistant and resistant isolates, the PCR-RFLP method could only be used for susceptible isolates and had poor sensitivity. Seminested-PCR was fast, sensitive for detection, and successfully differentiated between moderately and highly resistant S. pnemoniae; 96·1% of the PCR results were in agreement with the minimum inhibitory concentration (MIC) data. Conclusions: The penicillin resistance rate in isolates from children was much higher than of isolates from adults in China. Seminested-PCR for pbp1A was the best diagnostic method. Significance and Impact of the Study: We compared three different strategies for the first time in identification of PNSSP in China. In conclusion, seminested-PCR can be applied in clinical microbiology laboratories for detection of serious infections caused by S. pneumoniae. [ABSTRACT FROM AUTHOR]

Streptococcus agalactiae is a causal agent of bovine mastitis and is treated by β-lactam antibiotics (BLAs). Compared to penicillin-resistant S. agalactiae from humans, resistant strains in bovine are rarely reported. In this study, we aimed to investigate BLA resistance and mutations in penicillin-binding proteins (PBPs) of S. agalactiae in central and northeast China. The minimum inhibitory concentrations (MICs) of 129 penicillin-resistant S. agalactiae isolates from cows with mastitis were determined, and the related PBP genes were detected and sequenced. All strains were unsusceptible to penicillin G and mostly resistant to ampicillin, cefalexin, and ceftiofur sodium. One hundred twenty-nine strains were divided into 4 clonal groups and 8 sequence types by multilocus sequence typing analysis. We found a set of new substitutions in PBP1B, PBP2B, and PBP2X from most strains isolated from three provinces. The strains with high PBP mutations showed a broader unsusceptible spectrum and higher MICs than those with few or single mutation. Our research indicates unpredicted mutations in the PBP genes of S. agalactiae isolated from cows with mastitis treated by BLAs. This screening is the first of S. agalactiae from cattle.

This study examined the epidemiology, antibiotic susceptibility, and serotype distribution of Streptococcus pneumoniae associated with invasive and noninvasive pneumococcal disease in children in China. A total of 451 clinical isolates from children (age, <5 years) were collected from 8 cities from January 2005 to December 2006, including 31 isolated from invasive disease. In vitro susceptibility to 14 antimicrobial agents was determined by the agar dilution method. Among all isolates tested, 64.3% were resistant to penicillin, and for invasive isolates, the resistance rate was 55.2%. Isolates from Wuhan and Nanjing showed the highest prevalence of penicillin resistance (89.6% and 85%), followed by those from Shenzhen (72.4%) and Chengdu (56.7%). Multidrug resistance rates to tetracycline, erythromycin, and clindamycin reached 90%. The 6 most common serotypes were 19F, 19A, 14, 6B, 23F, and 15. These accounted for 80.7% of the isolates. Resistance to penicillin varied among the 6 leading serotypes, ranging from 20% in serotype 15 to 87.3% in serotype 19F. Each of the 8 cities had different serotype distribution. The potential coverage by 7-, 10-, and 13-valent pneumococcal conjugate vaccine were 63.6%, 64.8%, and 79.6%, respectively.

The aim of this study was to investigate the nature of the amino acid motifs found in penicillin-binding proteins (PBP) 2b, 2x, and 1a of penicillin-nonsusceptible Streptococcus pneumoniae isolates from Shenyang, China, and to obtain information regarding the prevalence of alterations within the motifs or in positions flanking the motifs. For 18 clinical isolates comprising 4 penicillin-susceptible S. pneumoniae, 5 penicillin-intermediate S. pneumoniae, and 9 penicillin-resistant S. pneumoniae. the DNA sequences of PBP2b, PBP2x, and PBP1a transpeptidase domains were determined and then genotyped by multilocus sequence typing. Sequence analysis revealed that most penicillin-nonsusceptible S. pneumoniae isolates (penicillin MIC > or = 1.5 microg/mL and cefotaxime MIC > or = 2 microg/mL) shared identical PBP2b, PBP2x, and PBP1a amino acid profiles. Most penicillin-resistant S. pneumoniae isolates were ST320 (4-16-19-15-6-20-1), the double-locus variant of the Taiwan19F-14 clone. This study will serve as a basis for future monitoring of genetic changes associated with the emergence and spread of beta-lactam resistance in Shenyang, China.

To elucidate alternations in gene/amino acid sequence of penicillin-binding proteins (PBPs) 1A, 2B, 2X from clinical isolates of penicillin-resistant Streptococcus pneumonia (PRSP) in Zhejiang Province, 26 strains of Streptococcus pneumonia were collected from November 2001 to January 2004. The antibiotics susceptibility of these strains was detected. PCR amplification and direct sequencing of PBP1A, 2B, 2X genes were performed. The sequence variations of PBP genes of the PRSPs in this region were studied by sequence BLAST analysis. It was shown that the main alternations of PBP1A were the four consecutive amino acid substitutions (Thr574Ala, Ser575Thr, Gln576Gly, Phe577Tyr) following the conservative motif KTG and the amino acid substitution Thr371Ser in the conservative motif STMK. The main alternation of PBP2B was Thr451Ala following the conservative motif SSN, and the main alternation of PBP2X was Thr338Ala in conservative motif STMK. The above mutation sites and drug resistant level were consistent to the data reported previously. Neither new gene mutation specific to these strains nor certain amino acid substitutions related to penicillin resistance reported was identified in the genes.

Objective: To evaluate the antibiotic susceptibility of Neisseria gonorrhoeae epidemic strains in Changsha and to provide a reference for the prevention and treatment of gonorrhea., Methods: beta-Lactamase was determined by a modified iodometric method and the susceptibility to 9 antibiotic agents was tested by the disc diffusion method in 86 isolates., Results: Plasmid-mediated penicillinase-producing Neisseria gonorrhoeae and plasmid-mediated tetracycline-resistant Neisseria gonorrhoeae were 40.69% and 23.26%, respectively. Of all the 9 antibiotic agents, tetracycline, cefmetazole, penicillin, ciprofloxacin, and ofloxacin had a higher resistance and the percentages of resistance were 45.35%, 50.00%, 62.79%, 77.91%, and 87.21%, respectively. On the other hand, cefuroxime, ceftriaxone, cefepime, and spectinomycin had a higher susceptibility and the percentages of susceptibility were 77.91%, 80.23%, 86.05%, and 98.84%, respectively., Conclusion: Penicillin, tetracycline and fluoroquinolone can not be used as routine agents to cure gonorrhea; and spectinomycin can be used as primary medicine to cure gonorrhea in Changsha, but clinical doctors need to pay more attention to it because resistant strains have come into existence.

Three-hundred and seventy-six strains of Streptococcus pneumoniae isolated from clinical specimens and nasopharyngeal swabs from children at daycare centers and hospitals in Beijing China, between January 1997 and March 1998, were serotyped. Twenty-seven different serotypes were identified. The most prevalent serotypes in the carriage isolates were 6A, 19F, 23F, and 15 and were found in 66.8% of cases. Serotype data indicate that 51.8% of carrier strains would be included in the 11-valent conjugate vaccine formulation, while inclusion of vaccine-related serotypes, increased the potential vaccine coverage to 79.4%. Serotypes 7, 6B, 23F, 19F, 15, and 3 accounted for 62% of clinical strains, with 70% vaccine-related serotypes. DNA fingerprinting of 47 penicillin resistant and 71 penicillin-susceptible/macrolide-resistant strains by BOX polymerase chain reaction (PCR), pulsed-field gel electrophoresis (PFGE), and penicillin binding protein (PBP)-fingerprinting identified two novel clones: one a serotype 23F multiresistant clone resistant to penicillin, tetracycline, erythromycin, clindamycin, and variably resistant to chloramphenicol and trimethoprim-sulphamethoxazole; and the second a multiresistant penicillin-susceptible, macrolide-resistant serotype 6A clone, highly resistant also to tetracycline, clindamycin, and trimethoprim-sulphamethoxazole. The macrolide resistance determinant in 89% of erythromycin-resistant strains tested (penicillin-susceptible and penicillin-resistant) was the erm gene, both the erm and mef genes were simultaneously found in 6%, and mef alone in 3.4%. The data demonstrates that macrolide resistant strains in China include clonal strains and strains with dual mef and erm resistance determinants.

Objective: To investigate antimicrobial resistance of Streptococcus pneumoniae in Beijing and molecular epidemiology of penicillin-resistant pneumococci strains., Methods: The resistance to beta-lactam and non-beta-lactam antibiotics of 244 nasopharyngeal isolates of Streptococcus pneumoniae collected from September to November 1997 in 8 day-care centers in Beijing was studied by Etest and agar dilution method. Serotyping was done by "capsular swelling" technique. BOX-PCR technique was used to detect the DNA of resistant strains., Results: 24.8% (244/985) of the children carried Streptococcus pneumoniae. The agreement between the MICs obtained by Etest and agar dilution for penicillin and ceftriaxone was > 93.7%. By Etest, 3/244 (1.3%) strains were resistant to penicillin(MICs, 3 micrograms/ml) and 32/244(13.1%) strains in termedinte (MICs, 0.094-0.25 microgram/ml). Penicillin-susceptible strains were also susceptible to the other 4 tested beta-lactams. In penicillin non-susceptible strains, 11.4% (4/35) isolates were resistant to the other beta-lactams. The resistant rates of erythromycin, tetracycline, chloramphenicol and trimethoprim-sulfamethoxazole (TMP-SMZ) were 74.0%, 87.6%, 47.8%, 63.3%, respectively. All of the strains were susceptible to vancomycin and rifampin. 119/244(48.7%) strains isolated were multiresistant to tetracycline, erythromycin and TMP/SMZ. Serotype 6A(33.6%), 19F(16.8%), 23F(15.1%), 15(11.2%), 6B(4.3%) were most common. 57.1% (20/35) penicillin non-susceptible strains were of serotype 23F and had similar or identical multiresistance and BOX patterns., Conclusion: In Beijing, the prevalence of penicillin-resistant pneumococci was obviously lower than that of neighboring countries, but resistant rate to non-beta-lactams was high. The epidemic multiresistant 23F clone found in day-care centers was different from the Spanish clone.

The sensitivity of 95 strains of N. gonorrhoeae to antibiotics was determined. In 1990, among 18 strains of N. gonorrhoeae, 7 (38.90%) were resistant to Penicillin G, 3 (16.66%) to Gentamicin, 8 (44.44%) Kanamycin, 8 (44.44%) Midecamycin. In 1992, among 77 strains of N. gonorrhoeae, 61 (79.22%) were resistant to Penicillin G, 38 (49.35%) to Gentamicin, 62 (80.52%) to Kanamycin, 54 (70.13%) to Midecamycin, 56 (72.72%) to Ampicillin 60 (77.92%) to Erythromycin, 22 (28.57%) to Cefazolin, 18 (23.37%) to Cefotaxime. The results showed that Cefazolin and Cefotaxime were the most effective antibiotics, Gentamicin was the next.

A series of clinical isolates of methicillin resistant Staphylococcus aureus (MRSA) from two hospitals in China was examined. Fragment patterns obtained by digestion of total cellular DNA with restriction enzymes were used to characterize the isolates, in combination with phage-typing, antibiotic resistance profile, and plasmid profile. Digestion of total cellular DNA with restriction enzymes was most useful in discriminating between isolates and yielded additional information on the relatedness of non-identical isolates. In one hospital a single strain, resistant to a large number of antibiotics, had apparently become endemic. In the second hospital a number of distinct but related strains were present. The isolates were also related but not identical to the strain of MRSA endemic at the London Hospital.