Markedly Increasing Antibiotic Resistance and Dual Treatment of Neisseria gonorrhoeae Isolates in Guangdong, China, from 2013 to 2020.

The emergence of multidrug resistance in Neisseria gonorrhoeae is concerning, especially the cooccurrence of azithromycin resistance and decreased susceptibility to extended-spectrum cephalosporin. This study aimed to confirm the antibiotic resistance trends and provide a solution for N. gonorrhoeae treatment in Guangdong, China. A total of 5,808 strains were collected for assessment of antibiotic MICs. High resistance to penicillin (53.80 to 82%), tetracycline (88.30 to 100%), ciprofloxacin (96 to 99.8%), cefixime (6.81 to 46%), and azithromycin (8.60 to 20.03%) was observed. Remarkably, spectinomycin and ceftriaxone seemed to be the effective choices, with resistance rates of 0 to 7.63% and 2.00 to 16.18%, respectively. Moreover, the rates of azithromycin resistance combined with decreased susceptibility to ceftriaxone and cefixime reached 9.28% and 8.64%, respectively. Furthermore, genotyping identified NG-STAR-ST501, NG-MAST-ST2268, and MLST-ST7363 as the sequence types among representative multidrug-resistant isolates. Evolutionary analysis showed that FC428-related clones have spread to Guangdong, China, which might be a cause of the rapid increase in extended-spectrum cephalosporin resistance currently. Among these strains, the prevalence of N. gonorrhoeae was extremely high, and single-dose ceftriaxone treatment might be a challenge in the future. To partially relieve the treatment pressure, a susceptibility test for susceptibility to azithromycin plus extended-spectrum cephalosporin dual therapy was performed. The results showed that all the representative isolates could be effectively killed with the coadministration of less than 1 mg/liter azithromycin and 0.125 mg/liter extended-spectrum cephalosporin, with a synergistic effect according to a fractional inhibitory concentration (FIC) of <0.5. In conclusion, dual therapy might be a powerful measure to treat refractory N. gonorrhoeae in the context of increasing antibiotic resistance in Guangdong, China.

Prevalence and Predictors of Third-Generation Cephalosporin Resistance in the Empirical Treatment of Spontaneous Bacterial Peritonitis.

OBJECTIVE: To better characterize the changing patterns of spontaneous bacterial peritonitis (SBP) in a tertiary academic center in the United States by identifying the prevalence of gram-positive organisms and cephalosporin resistance along with predictors of mortality and antibiotic drug resistance. PATIENTS AND METHODS: We reviewed 481 consecutive patients with SBP at Mayo Clinic in Rochester, Minnesota, from January 1, 2005, through December 31, 2016. Data on comorbid conditions, etiology of cirrhosis, factors predisposing to infection, and antimicrobial and antibiotic drug use were collected. RESULTS: We identified 96 patients (20%) with culture-positive SBP requiring treatment (median age, 60 years; age range, 22-87 years; 44% men). Gram-positive organisms account for more than half of the cases. Overall resistance to third-generation cephalosporins was 10% (n=10). Risk factors for third-generation cephalosporin resistance include nosocomial acquisition, recent antibiotic drug use, and hepatocellular carcinoma. The negative predictive value for antibiotic drug resistance in the present model was 96% (70 of 73). Overall mortality at 30 and 90 days was 23% and 37%, respectively. CONCLUSION: These findings support the recent observation of a rising prevalence of gram-positive organisms in SBP. Despite the changing pattern, third-generation cephalosporins seem to provide adequate empirical treatment in patients with community-acquired and health care-associated SBP without hepatocellular carcinoma.

Evaluation of Susceptibilities to Carbapenems and Faropenem Against Cephalosporin-Resistant Neisseria gonorrhoeae Clinical Isolates with penA Mosaic Alleles.

Neisseria gonorrhoeae is a principal pathogen for sexually transmitted infections, especially for male urethritis. Currently, the prevalence of multidrug resistance is increasing. Carbapenems are broad-spectrum antimicrobials that are widely used in the clinical setting, especially for multidrug-resistant Gram-negative bacteria. However, susceptibility to carbapenems has not been well evaluated for cephalosporin-resistant N. gonorrhoeae isolates. In this study, we determined the susceptibility to a series of carbapenems (meropenem, imipenem, doripenem, and biapenem) and faropenem against cephalosporin-resistant (resistant to cefixime, but susceptible to ceftriaxone) and cephalosporin-susceptible N. gonorrhoeae clinical isolates. The gene mutations associated with ß-lactam resistance were evaluated. All cephalosporin-resistant N. gonorrhoeae isolates possessed mosaic mutation alleles in penA (NG-STAR penA-10.001, 27.001, or 108.001). They exhibited a low minimum inhibitory concentration (MIC) (≤0.125 mg/L) for meropenem and markedly high MICs (0.5-2 mg/L) for other carbapenems and faropenem. The strongest association was observed between the mosaic alleles in penA and decreased susceptibility to carbapenems and faropenem compared with mutations in mtrR, porB, and ponA. These results suggest that meropenem may serve as an alternative therapeutic agent for cephalosporin-resistant N. gonorrhoeae with a mosaic allele in penA, whereas other carbapenems and faropenem may be ineffective.

Epidemiological situation of enterobacteriaceae resistant to cephalosporins third generation in the region of Mahdia, Tunisia (2002-2014).

OBJECTIVES: To determine the prevalence and to monitor the trends of resistance to broad-spectrum cephalosporins among various species of enterobacteria in the region of Mahdia (Tunisia) from 2002 to 2014. METHODS: A retrospective study was carried out in the microbiology laboratory at Tahar Sfar Teaching Hospital in Mahdia. Data concerning a thirteen-year period (2002-2014). All clinical isolates of enterobacteriaceae were identified with the API 20 E system. Antimicrobial susceptibilities were determined by disk diffusion on Mueller Hinton agar according to CA-SFM recommendations. RESULTS: During the study period, 25040 non-duplicate clinical strains of enterobacteriacae were identified. 2584 (10,3%) clinical isolates showed acquired resistance to third generation cephalosporins (3rdGC). The overall frequency of resistance increased from 8% in 2002 to 16,3% in 2014. This increase was statistically significant. High prevalence rates of 3rdGC resistance have been observed in pediatric (25,1%), in gynecologyobstetrics (21,9%) and medecine (17,4%). E. coli (21,6%), K. pneumoniae (28,6%) and E. cloacae (30,5%) showed high prevalence rates of broad-spectrum cephalosporin resistance. CONCLUSION: The resistance rates ERC3G in our region seems to be increasing. Implementation of infection control measures and identification of the mechanism responsible for third generation cephalosporins resistance are necessary to limit the spreading of these resistant enterobacteriaceae in hospitals and community settings.

Poor clinical outcomes associated with community-onset urinary tract infections due to extended-spectrum cephalosporin-resistant Enterobacteriaceae.

OBJECTIVE: Resistance to extended-spectrum cephalosporins (ESC) among Enterobacteriaceae (EB) is increasingly prevalent. We sought to determine the clinical outcomes associated with community-onset ESC-resistant (ESC-R) EB urinary tract infections (UTIs) in a US health system. DESIGN: Retrospective cohort study.PatientsAll patients presenting to the emergency departments (EDs) or outpatient practices with EB UTIs between 2010 and 2013 were included. Exposed patients had ESC-R EB UTIs. Unexposed patients had ESC-susceptible EB UTIs and were matched to exposed subjects 1:1 on study year. Multivariable logistic regression analyses were performed to evaluate the association between ESC-R EB UTI and the outcomes of clinical failure and inappropriate initial antibiotic therapy (IIAT). RESULTS: A total of 302 patients with community-onset EB UTI were included, with 151 exposed and unexposed. On multivariable analyses, UTI due to an ESC-R EB was significantly associated with clinical failure (odds ratio [OR], 7.07; 95% confidence interval [CI], 3.16-15.82; P<.01). Other independent risk factors for clinical failure included infection with Citrobacter spp and need for hemodialysis. UTI due to an ESC-R EB was also significantly associated with IIAT (OR, 4.40; 95% CI, 2.64-7.33; P<.01). CONCLUSIONS: Community-onset UTI due to an ESC-R EB organism is significantly associated with clinical failure, which may be due in part to IIAT. Further studies are needed to determine which patients in the community are at high risk for drug-resistant infection to help inform prompt diagnosis and appropriate antibiotic prescribing for ESC-R EB.

Increases in Neisseria gonorrhoeae With Reduced Susceptibility to Azithromycin Among Men Who Have Sex With Men in Seattle, King County, Washington, 2012-2016.

Background: Antimicrobial-resistant Neisseria gonorrhoeae is a major public health threat. The Centers for Disease Control and Prevention (CDC) recommends ceftriaxone 250 mg plus azithromycin (AZM) 1 g for gonorrhea treatment. Resistance to AZM could affect gonorrhea control efforts. Methods: Using gonococcal isolates collected at the Public Health-Seattle & King County (PHSKC) Sexually Transmitted Disease (STD) Clinic from 2012 to 2016, focusing on 2014-2016, we compared cases with the CDC AZM alert value minimum inhibitory concentration (MIC) (≥2 µg/mL) to those with AZM MIC ≤1 µg/mL, antimicrobial susceptibility profiles and clinical outcomes. Results: In 2012 and 2013, none of the 263 patients from whom we isolated N. gonorrhoeae from the urethra were infected with organisms with an AZM MIC ≥2 µg/mL. Between 2014 and 2016, 4.4% of 926 gonorrhea cases demonstrated reduced susceptibility to AZM; 93% of these cases occurred among men who have sex with men (MSM). Among MSM, 5.0% of 2014-2016 cases demonstrated reduced susceptibility to AZM. No AZM alert value isolates had concomitant cephalosporin resistance. There were 2 potential treatment failures: 1 pharyngeal infection treated with AZM 2 g alone, and 1 pharyngeal infection that persisted after study drug. Conclusions: Among MSM with gonorrhea in Seattle, 5% have gonorrhea with reduced susceptibility to AZM. The World Health Organization recommends changing treatment guidelines when >5% of isolates are resistant to a recommended drug. The emergence of resistant AZM gonorrhea should prompt reconsideration of current treatment recommendations, and highlights the need for new therapies for gonorrhea.

Antibiotic Prophylaxis Is Associated with Subsequent Resistant Infections in Children with an Initial Extended-Spectrum-Cephalosporin-Resistant Enterobacteriaceae Infection.

The objective of this study was to assess the association between previous antibiotic use, particularly long-term prophylaxis, and the occurrence of subsequent resistant infections in children with index infections due to extended-spectrum-cephalosporin-resistant Enterobacteriaceae We also investigated the concordance of the index and subsequent isolates. Extended-spectrum-cephalosporin-resistant Escherichia coli and Klebsiella spp. isolated from normally sterile sites of patients aged <22 years were collected along with associated clinical data from four freestanding pediatric centers. Subsequent isolates were categorized as concordant if the species, resistance determinants, and fumC-fimH (E. coli) or tonB (Klebsiella pneumoniae) type were identical to those of the index isolate. In total, 323 patients had 396 resistant isolates; 45 (14%) patients had ≥1 subsequent resistant infection, totaling 73 subsequent resistant isolates. The median time between the index and first subsequent infections was 123 (interquartile range, 43 to 225) days. In multivariable Cox proportional hazards analyses, patients were 2.07 times as likely to have a subsequent resistant infection (95% confidence interval, 1.11 to 3.87) if they received prophylaxis in the 30 days prior to the index infection. In 26 (58%) patients, all subsequent isolates were concordant with their index isolate, and 7 (16%) additional patients had at least 1 concordant subsequent isolate. In 12 of 17 (71%) patients with E. coli sequence type 131 (ST131)-associated type 40-30, all subsequent isolates were concordant. Subsequent extended-spectrum-cephalosporin-resistant infections are relatively frequent and are most commonly due to bacterial strains concordant with the index isolate. Further study is needed to assess the role prophylaxis plays in these resistant infections.

In vitro activity of ceftazidime/avibactam against urinary isolates from patients in a Phase 3 clinical trial programme for the treatment of complicated urinary tract infections.

Objectives: To evaluate the in vitro activity of ceftazidime/avibactam relative to comparator agents against Gram-negative isolates from a Phase 3 clinical trial programme for complicated urinary tract infections (RECAPTURE). Methods: The in vitro activity of ceftazidime/avibactam was evaluated against 840 Gram-negative pathogens isolated at baseline from 1033 randomized patients in two pivotal Phase 3 clinical trials for the treatment of complicated urinary tract infections. The trials were conducted in 160 institutions from 25 countries worldwide. Susceptibility testing was performed by broth microdilution at a central laboratory according to CLSI methodologies. Results: Overall, ceftazidime/avibactam showed significant activity against the Enterobacteriaceae and Pseudomonas aeruginosa with MIC 90 values of 0.5 and 8 mg/L, respectively. Against the most common Enterobacteriaceae, MIC 90 values were 0.25 mg/L for Escherichia coli , 1 mg/L for Klebsiella pneumoniae , 0.06 mg/L for Proteus mirabilis and 2 mg/L for Enterobacter cloacae . The ceftazidime/avibactam MIC 90 for 154 ceftazidime-non-susceptible isolates of Enterobacteriaceae was 1 mg/L and the ceftazidime/avibactam MIC 90 for 15 non-susceptible isolates of P. aeruginosa was 64 mg/L. There was a significant reduction in the ceftazidime/avibactam MIC relative to ceftazidime alone for most of the Enterobacteriaceae isolates. Conclusions: The ceftazidime/avibactam in vitro activity against these clinical urinary tract isolates demonstrates the potential utility of the drug in complicated urinary tract infections.

Clinical presentations, risk factors and outcomes of ceftazidime-resistant Gram-negative endophthalmitis.

BACKGROUND: To describe the clinical features and outcomes of patients diagnosed with ceftazidime-resistant Gram-negative endophthalmitis and the role of intravitreal imipenem in these cases. DESIGN: Retrospective consecutive interventional case series at a tertiary eye care centre in South India. PARTICIPANTS: Consecutive cases of ceftazidime-resistant Gram-negative endophthalmitis from April 2010 to December 2014. Fifty-six cases diagnosed during this time period were included. METHODS: All cases were managed with vitreous biopsy/vitrectomy, microscopy and undiluted vitreous culture, antimicrobial susceptibility of bacterial isolates and received intravitreal antibiotics. MAIN OUTCOME MEASURES: Anatomic and visual outcome of these cases, antimicrobial susceptibility pattern of intravitreal imipenem and outcome of cases injected with it. RESULTS: Commonest presentation was acute endophthalmitis following cataract surgery (27 eyes, 48.21%). Pseudomonas aeruginosa was isolated in 33 eyes (58.93%; 95% CI 46.05-71.81%). Nineteen eyes (34%; 95% CI 21.59-46.41%) developed phthisis; 14 eyes (25%; 95% CI 13.66-36.34%) had vision <20/200; 17 eyes (30.35%; 95% CI 18.31-42.39%) eyes had an ambulatory vision >20/200 (logMAR 1); 6 eyes (10.71%; 95% CI 2.61-18.81%) had a reading vision >20/40 (logMAR 0.3). Trend was towards better anatomic (72.73% vs. 40%) (P = 0.05) and visual improvement in the imipenem group (logMAR 3.94 + 0.21 to 2.43 + 1.4; P = 0.002), as compared with non-imipenem group (logMAR 2.99 + 1.3 to 2.55 + 1.4; P = 0.13). CONCLUSIONS: Outcome of ceftazidime-resistant Gram-negative endophthalmitis is poor. P. aeruginosa is the commonest isolated organism. All cases were sensitive to imipenem. There was a trend towards better anatomic outcome in imipenem-treated eyes.

Helicobacter cinaedi bacteremia resulting from antimicrobial resistance acquired during treatment for X-linked agammaglobulinemia.

This is the first report of penicillin/cephalosporin-resistant Helicobacter cinaedi arising from prolonged treatment. H. cinaedi, common among immunocompromised patients, caused recurrent bacteremia and cellulitis in a 19-year-old Japanese man with X-linked agammaglobulinemia. The minimal inhibitory concentration of these drugs was raised, which subsequently resulted in clinical failure. Prolonged suboptimal treatment may cause bacterial resistance to ß-lactam antibiotics in H. cinaedi. It is possible that this resistance may have contributed to the treatment failure.

Genomic epidemiology of Neisseria gonorrhoeae with reduced susceptibility to cefixime in the USA: a retrospective observational study.

BACKGROUND: The emergence of Neisseria gonorrhoeae with decreased susceptibility to extended spectrum cephalosporins raises the prospect of untreatable gonorrhoea. In the absence of new treatments, efforts to slow the increasing incidence of resistant gonococcus require insight into the factors that contribute to its emergence and spread. We assessed the relatedness between isolates in the USA and reconstructed likely spread of lineages through different sexual networks. METHODS: We sequenced the genomes of 236 isolates of N gonorrhoeae collected by the Centers for Disease Control and Prevention's Gonococcal Isolate Surveillance Project (GISP) from sentinel public sexually transmitted disease clinics in the USA, including 118 (97%) of the isolates from 2009-10 in GISP with reduced susceptibility to cefixime (cef(RS)) and 118 cefixime-susceptible isolates from GISP matched as closely as possible by location, collection date, and sexual orientation. We assessed the association between antimicrobial resistance genotype and phenotype and correlated phylogenetic clustering with location and sexual orientation. FINDINGS: Mosaic penA XXXIV had a high positive predictive value for cef(RS). We found that two of the 118 cef(RS) isolates lacked a mosaic penA allele, and rechecking showed that these two were susceptible to cefixime. Of the 116 remaining cef(RS) isolates, 114 (98%) fell into two distinct lineages that have independently acquired mosaic penA allele XXXIV. A major lineage of cef(RS) strains spread eastward, predominantly through a sexual network of men who have sex with men. Eight of nine inferred transitions between sexual networks were introductions from men who have sex with men into the heterosexual population. INTERPRETATION: Genomic methods might aid efforts to slow the spread of antibiotic-resistant N gonorrhoeae through augmentation of gonococcal outbreak surveillance and identification of populations that could benefit from increased screening for asymptomatic infections.

Phenotypic and genetic characterization of the first two cases of extended-spectrum-cephalosporin-resistant Neisseria gonorrhoeae infection in South Africa and association with cefixime treatment failure.

OBJECTIVES: To describe the phenotypic and genetic characteristics of the first two cases of extended-spectrum cephalosporin (ESC)-resistant Neisseria gonorrhoeae in South Africa, one of which was associated with verified cefixime treatment failure. PATIENTS AND METHODS: Two ESC-resistant N. gonorrhoeae isolates were cultured from the urethral discharge of two men who have sex with men (MSM). One man reported a persistent urethral discharge that had failed to respond to previous therapy with oral cefixime. Agar dilution MICs were determined for eight antibiotics. ß-Lactam-associated resistance mutations were identified through PCR-based amplification and sequencing for several key genes: penA, mtrR and its promoter, porB1b (penB), ponA and pilQ. For molecular epidemiological characterization, full-length porB gene sequencing, N. gonorrhoeae multiantigen sequence typing (NG-MAST) and multilocus sequence typing (MLST) were performed. RESULTS: Both isolates were resistant to cefixime, ciprofloxacin, penicillin and tetracycline and intermediate/resistant to azithromycin, but susceptible to ceftriaxone, gentamicin and spectinomycin. Both isolates had the type XXXIV penA mosaic allele in addition to previously described resistance mutations in the mtrR promoter (A deletion), porB1b (penB) (G101K and A102N) and ponA1 (L421P). Both isolates had an identical NG-MAST sequence type (ST4822) and MLST sequence type (ST1901). CONCLUSIONS: Both isolates were resistant to cefixime and possessed a number of identical mutations in key genes contributing to ESC resistance in N. gonorrhoeae. The two isolates contained the type XXXIV penA mosaic allele and belonged to a successful international MSM-linked multidrug-resistant gonococcal clone (MLST ST1901) associated with several cefixime treatment failures in Europe and North America.

[Emergence of resistance to third generation cephalosporins by Enterobacteriaceae causing community-onset urinary tract infections in hospitals in Colombia]. / Emergencia de fenotipos resistentes a cefalosporinas de tercera generación en Enterobacteriaceae causantes de infección del tracto urinario de inicio comunitario en hospitales de Colombia.

INTRODUCTION: Urinary tract infection (UTI) is a common disease in the community, and a matter of concern due to the increasing resistance of microorganisms to first line antibiotics and the emergence of multiresistant strains producing extended spectrum beta lactamases (ESBL) in the community. METHODS: An analytical case-control study was conducted over twelve months in 9 hospitals in Colombia. We collected isolates of E. coli, Klebsiella spp. and Proteus spp. from patients with community-onset UTI. The presence of ESBL, AmpC and KPC beta-lactamases were characterized by microbiological and molecular methods. The aim of this study was to determine factors related to the presence of these mechanisms of the resistance to third generation cephalosporins. RESULTS: A total of 325 isolates (287 E. coli, 29 Klebsiella spp. and 9 Proteus spp.) were included. The most frequent comorbidities among the patients were hypertension (n=82; 25.2%) and diabetes mellitus (n=68; 20.9%). Previous use of antimicrobials was found in 23% of patients, and 29% had a previous UTI. Resistance to third and fourth generation cephalosporins varied between 3.4% and 6.3% in E. coli and between 6.9% and 17.8% in K. pneumoniae. Seven (2.4%) CTX-M-15 ESBL-producing E. coli isolates were detected; four of them belonged to ST 131 clone. In K. pneumoniae we detected three KPC-3 carbapenemases (10.3%). CONCLUSIONS: This study confirms the emergence of resistance to third generation cephalosporins enterobacteriaceae as a cause of community-onset UTI. We emphasize the presence of ST 131 clone and KPC carbapenemases circulating in Colombia outside the hospital environment.

Clinical and Molecular Epidemiology of Community-Onset Bacteremia Caused by Extended-Spectrum beta-Lactamase-Producing Escherichia coli over a 6-Year Period

Although extended-spectrum beta-lactamase-producing Escherichia coli (ESBL-EC) has emerged as a significant community-acquired pathogen, there is little epidemiological information regarding community-onset bacteremia due to ESBL-EC. A retrospective observational study from 2006 through 2011 was performed to evaluate the epidemiology of community-onset bacteremia caused by ESBL-EC. In a six-year period, the proportion of ESBL-EC responsible for causing community-onset bacteremia had increased significantly, from 3.6% in 2006 to 14.3%, in 2011. Of the 97 clinically evaluable cases with ESBL-EC bacteremia, 32 (33.0%) were further classified as healthcare-associated infections. The most common site of infection was urinary tract infection (n=35, 36.1%), followed by biliary tract infections (n=29, 29.9%). Of the 103 ESBL-EC isolates, 43 (41.7%) produced CTX-M-14 and 36 (35.0%) produced CTX-M-15. In the multilocus sequence typing (MLST) analysis of 76 isolates with CTX-M-14 or -15 type ESBLs, the most prevalent sequence type (ST) was ST131 (n=15, 19.7%), followed by ST405 (n=12, 15.8%) and ST648 (n=8, 10.5%). No significant differences in clinical features were found in the ST131 group versus the other group. These findings suggest that epidemic ESBL-EC clones such as CTX-M-14 or -15 type ESBLs and ST131 have disseminated in community-onset infections, even in bloodstream infections, which are the most serious type of infection.

In vitro activity of the new fluoroketolide solithromycin (CEM-101) against a large collection of clinical Neisseria gonorrhoeae isolates and international reference strains, including those with high-level antimicrobial resistance: potential treatment option for gonorrhea?

Gonorrhea may become untreatable, and new treatment options are essential. We investigated the in vitro activity of the first fluoroketolide, solithromycin. Clinical Neisseria gonorrhoeae isolates and reference strains (n = 246), including the two extensively drug-resistant strains H041 and F89 and additional isolates with clinical cephalosporin resistance and multidrug resistance, were examined. The activity of solithromycin was mainly superior to that of other antimicrobials (n = 10) currently or previously recommended for gonorrhea treatment. Solithromycin might be an effective treatment option for gonorrhea.

Effects of silver-based wound dressings on the bacterial flora in chronic leg ulcers and its susceptibility in vitro to silver.

Silver-based dressings have been used extensively in wound management in recent years, but data on their antimicrobial activity in the clinical setting are limited. In order to explore their effects on chronic leg ulcer flora, 14 ulcers were cultured after at least 3 weeks treatment with Aquacel Ag(®) or Acticoat(®). Phenotypic and genetic silver resistance were investigated in a total of 56 isolates. Silver-based dressings had a limited effect on primary wound pathogens, which were present in 79% of the cultures before, and 71% after, treatment. One silver-resistant Enterobacter cloacae strain was identified (silver nitrate minimal inhibitory concentration (MIC) > 512 mg/l, positive for silE, silS and silP). Further studies in vitro showed that inducible silver-resistance was more frequent in Enterobacteriaceae with cephalosporin-resistance and that silver nitrate had mainly a bacteriostatic effect on Staphylococcus aureus. Monitoring of silver resistance should be considered in areas where silver is used extensively.

High-level cefixime- and ceftriaxone-resistant Neisseria gonorrhoeae in France: novel penA mosaic allele in a successful international clone causes treatment failure.

Recently, the first Neisseria gonorrhoeae strain (H041) highly resistant to the expanded-spectrum cephalosporins (ESCs) ceftriaxone and cefixime, which are the last remaining options for first-line gonorrhea treatment, was isolated in Japan. Here, we confirm and characterize a second strain (F89) with high-level cefixime and ceftriaxone resistance which was isolated in France and most likely caused a treatment failure with cefixime. F89 was examined using six species-confirmatory tests, antibiograms (33 antimicrobials), porB sequencing, N. gonorrhoeae multiantigen sequence typing (NG-MAST), multilocus sequence typing (MLST), and sequencing of known gonococcal resistance determinants (penA, mtrR, penB, ponA, and pilQ). F89 was assigned to MLST sequence type 1901 (ST1901) and NG-MAST ST1407, which is a successful gonococcal clone that has spread globally. F89 has high-level resistance to cefixime (MIC = 4 µg/ml) and ceftriaxone (MIC = 1 to 2 µg/ml) and resistance to most other antimicrobials examined. A novel penA mosaic allele (penA-CI), which was penA-XXXIV with an additional A501P alteration in penicillin-binding protein 2, was the primary determinant for high-level ESC resistance, as determined by transformation into a set of recipient strains. N. gonorrhoeae appears to be emerging as a superbug, and in certain circumstances and settings, gonorrhea may become untreatable. Investigations of the biological fitness and enhanced understanding and monitoring of the ESC-resistant clones and their international transmission are required. Enhanced disease control activities, antimicrobial resistance control and surveillance worldwide, and public health response plans for global (and national) perspectives are also crucial. Nevertheless, new treatment strategies and/or drugs and, ideally, a vaccine are essential to develop for efficacious gonorrhea management.

Penicillin and ceftriaxone susceptibility of Streptococcus pneumoniae isolated from cerebrospinal fluid of children with meningitis hospitalized in a tertiary hospital in Israel.

BACKGROUND: Streptococcus pneumoniae is now the predominant pathogen causing meningitis. The resistance of S. pneumoniae to penicillin and third-generation cephalosporins has grown steadily. OBJECTIVES: To assess the antibiotic susceptibility of S. pneumoniae isolated from the cerebrospinal fluid of children with meningitis, and determine the antibiotic regimen appropriate for suspected bacterial meningitis in Israel. METHODS: The study group included 31 children with 35 episodes of meningitis hospitalized from 1998 to 2006. S. pneumoniae isolates from the cerebrospinal fluid were tested for susceptibility to penicillin and ceftriaxone. RESULTS: Of the 35 isolates, 17 (48.6%) showed resistance to penicillin (minimum inhibitory concentration > or = 0.12 microg/ml). Only 3 isolates (8.6%) showed intermediate resistance to ceftriaxone (> or = 0.5 and < (2 microg/ml), and none showed complete resistance (MIC > or = 2 microg/ml). The rates of antibiotic resistance were higher in children who were treated with antibiotics prior to admission (penicillin 88.9% vs. 34.6%, P = 0.007; ceftriaxone 22.2% vs. 3.8%, P = 0.156). CONCLUSIONS: The rate of penicillin resistance is high in children with S. pneumoniae meningitis in Israel, especially in those treated with oral antibiotics prior to admission. Resistance to ceftriaxone is infrequent though not negligible. On the basis of these findings, current recommendations to empirically treat all children with suspected bacterial meningitis with ceftriaxone in addition to vancomycin until the bacterial susceptibility results become available are justified also in Israel.

Detecção de metalo-beta-lactamases em amostras de pseudomonas aeruginosa isoladas em Porto Alegre, Rio Grande do Sul / Detection of metallo-beta-lactamase producing pseudomonas aeruginosa isolated in Porto Alegre,Rio Grande do Sul, Brazil

As metalo-beta-lactamases (MBLs) pertencem ao grupo 3 de beta-lactamases de espectro estendido, fazendo parte de uma classefuncional de metaloenzimas classificadas com base na sua capacidade de hidrolisar os carbapenemicos como o Imipenem e em suas caracteristicas de serem inibidas por agentes quelantes como o acido etilenodiamino tetra-acetico (EDTA) e acido 2-mercaptopropionico (2-MPA). Este estudo objetivou a deteccao de MBLs em amostras nosocomiais de P. aeruginosa resistentes a Ceftazidima, provenientes de um hospital de medio porte de Porto Alegre-RS. Foram analisados 113 isolados clinicos atraves de testes fenotipicos, sendo: 80 (70,7%) do trato respiratorio inferior, 24 (21,2%) urina, 3 (2,7%) hemocultura, 3 (2,7%) ponta de cateter, 2 (1,8%) colecao de cavidadese 1 (0,9%) liquor. Com relacao a producao de MBLs, detectou-se 35 amostras (31,0%) como sendo produtoras.

Metallo-beta-lactamases belongs to the group 3 of extended spectrum beta-lactamases, making part of a common functional class of metal enzymes classified based in their ability to hydrolyze Imipenem and in your characteristics of been inhibited by ions of chelating metals, like EDTA and 2-MPA. The aim of this study was detect MBLs in samples of P. aeruginosa resistant to ceftazidime in the patients of PortoAlegre- RS Brazil. The samples was provided of different clinical specimens like: 80 (70,7%) respiratory tract, 24 (21,2%) urine, blood 3 (2,7%), catheter 3 (2,7%), 2 (1,8%) corporeal secretions and 1 (0,9%) liquor. With regard to the MBLs production, we detect 35 (31%) as being producing.