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Antimicrobial drug resistance remains a leading problem in modern healthcare, impacting on treatment options, mortality, infection control and economic issues. The introduction of new antimicrobial drugs has consistently been followed by the emergence of resistant bacteria. This review aims to answer the question of whether clinical improvement is likely if treatment of Staphylococcus aureus infections is attempted with an antimicrobial drug against which resistance is expressed in vitro (RD). Over time, S. aureus has acquired a broad range of antimicrobial resistance mechanisms, and methicillin-resistant S. aureus (MRSA) strains have become the most common multidrug-resistant healthcare-related infection-causing bacteria in Europe. As intention-to-treat studies with an RD would be unethical, only observational studies to evaluate the impact of RD therapy have been performed. Most of these studies bolster the assumption that RD therapy offers no benefit to the patient, but some do not show a detrimental effect. Limited antimicrobial treatment options for severe, invasive infections caused by MRSA might tempt physicians to use antimicrobials to which in vitro resistance is reported by the microbiological laboratory. Reasons for this non-evidence-based approach might include better pharmacokinetic/pharmacodynamic parameters, lower toxicity and better bioavailability in specific compartments, and/or the assumption of increased in vivo susceptibility of those microorganisms reported as resistant in vitro. In vitro resistance of a bacterium to a drug implies that exposing this bacterium to that drug should result in a worse clinical outcome than would be obtained with a drug to which resistance has not been observed (SD). As a counterpoint to in vitro resistance breakpoints, the concept of clinical breakpoints is therefore briefly revisited in this review. In a nutshell, no evidence has been published that S. aureus infections can be reliably treated with RDs, either as a single administration or in combination therapy.

The Commi t t ee for Japanese Standards for Antimicrobial Susceptibility Testing for Bacteria, Japan Society of Chemotherapy~ (chairman: Sachiko Goto, MD, Table 1) established the standard method of the Japan Society of Chemotherapy for microdilution antimicrobial susceptibility testing of bacteria that grow aerobically. 1 Fur thermore , the Commit tee (chairman: Atsushi Saito, MD) determined the standard method for microdilution antimicrobial susceptibility testing methods for bacteria that grow anaerobically and for bacteria that require special nutrients. 2 At the 41 st All Japan meet ing for the Japan Society of C h e m o t h e r a p y (Tokyo, 1993), the Commit tee proposed clinical breakpoints for antimicrobial agents which could be used in pu lmonary infections and sepsis, soliciting opinions from the m ember s of the Society.The originally proposed breakpoints were partially revised and here we submit the breakpoints in pu lmonary infections and sepsis as authorized by the Japan Society of Chemotherapy. I t would be ideal if breakpoints for ant imicrobial agents in any organ could be determined with the measu rement of M I C (minimum inhibitory concentrat ion), a quantitative designation of drug susceptibility. The breakpoints should be decided for each organ since concentration of antibiotics at each infection site differs depending upon location. Breakpoints used in mos t of the world comprise only one or two breakpoints, thus neglecting the infection site. 3,4 T h e N C C L S (Nat iona l C o m m i t t e e for Clinical Labora tory Standards) breakpoints extensively used in Japan ~,6 were determined on the available data, such as clinical dose and pharmacological kinetics, f rom American studies and are, therefore, not suitable for Japanese due to differing dose schedules.The breakpoints for Japanese should be investigated on the basis of the clinical

Item does not contain fulltext The European Committee on Antimicrobial Susceptibility Testing-Subcommittee on Antifungal Susceptibility Testing has determined breakpoints for anidulafungin for Candida spp. This Technical Note is based on the EUCAST anidulafungin rationale document (available at: http://www.eucast.org). Species-specific breakpoints for C. albicans are S 0.03 mg/L and for C. glabrata, C. tropicalis and C. krusei S 0.06 mg/L. C. parapsilosis was not regarded a good target for anidulafungin. There are insufficient data to set breakpoints for other species. The breakpoints are based upon pharmacokinetic data, epidemiological cut-off values and clinical experience. Breakpoints will be reviewed regularly.

The European Committee on Antimicrobial Susceptibility Testing-Subcommittee on Antifungal Susceptibility Testing (EUCAST-AFST) has determined breakpoints for amphotericin B for Candida spp. This Technical Note is based on the EUCAST amphotericin B rationale document (available on the EUCAST website: http://www.eucast.org). Species-specific breakpoints for C. albicans, C. glabrata, C. krusei, C. parapsilosis and C. tropicalis are S: MIC ≤1 mg/L, R: MIC > 1 mg/L. There are insufficient data to set breakpoints for other species. The breakpoints are based upon pharmacokinetic data, epidemiological cut-ff values and clinical experience. Breakpoints will be reviewed regularly.

Infection by Shigella spp. is a common cause of dysentery in Southeast Asia. Antimicrobials are thought to be beneficial for treatment; however, antimicrobial resistance in Shigella spp. is becoming widespread. We aimed to assess the frequency and mechanisms associated with decreased susceptibility to azithromycin in Southeast Asian Shigella isolates and use these data to assess appropriate susceptibility breakpoints. Shigella isolates recovered in Vietnam and Laos were screened for susceptibility to azithromycin (15 μg) by disc diffusion and MIC. Phenotypic resistance was confirmed by PCR amplification of macrolide resistance loci. We compared the genetic relationships and plasmid contents of azithromycin-resistant Shigella sonnei isolates using whole-genome sequences. From 475 available Shigella spp. isolated in Vietnam and Laos between 1994 and 2012, 6/181 S. flexneri isolates (3.3%, MIC ≥ 16 g/liter) and 16/294 S. sonnei isolates (5.4%, MIC ≥ 32 g/liter) were phenotypically resistant to azithromycin. PCR amplification confirmed a resistance mechanism in 22/475 (4.6%) isolates ( mphA in 19 isolates and ermB in 3 isolates). The susceptibility data demonstrated the acceptability of the S. flexneri (MIC ≥ 16 g/liter, zone diameter ≤ 15 mm) and S. sonnei (MIC ≥ 32 g/liter, zone diameter ≤ 11 mm) breakpoints with a S. sonnei isolates on at least seven occasions between 2000 and 2009 but failed to become established. While the proposed susceptibility breakpoints may allow better recognition of resistant isolates, additional studies are required to assess the impact on the clinical outcome. The potential emergence of azithromycin resistance highlights the need for alternative options for management of Shigella infections in countries where Shigella is endemic.

Infection by Shigella spp. is a common cause of dysentery in Southeast Asia. Antimicrobials are thought to be beneficial for treatment; however, antimicrobial resistance in Shigella spp. is becoming widespread. We aimed to assess the frequency and mechanisms associated with decreased susceptibility to azithromycin in Southeast Asian Shigella isolates and use these data to assess appropriate susceptibility breakpoints. Shigella isolates recovered in Vietnam and Laos were screened for susceptibility to azithromycin (15 μg) by disc diffusion and MIC. Phenotypic resistance was confirmed by PCR amplification of macrolide resistance loci. We compared the genetic relationships and plasmid contents of azithromycin-resistant Shigella sonnei isolates using whole-genome sequences. From 475 available Shigella spp. isolated in Vietnam and Laos between 1994 and 2012, 6/181 S. flexneri isolates (3.3%, MIC ≥ 16 g/liter) and 16/294 S. sonnei isolates (5.4%, MIC ≥ 32 g/liter) were phenotypically resistant to azithromycin. PCR amplification confirmed a resistance mechanism in 22/475 (4.6%) isolates (mphA in 19 isolates and ermB in 3 isolates). The susceptibility data demonstrated the acceptability of the S. flexneri (MIC ≥ 16 g/liter, zone diameter ≤ 15 mm) and S. sonnei (MIC ≥ 32 g/liter, zone diameter ≤ 11 mm) breakpoints with a

31 Pags., 2 Figs. The definitive version, with all tables and figures, is available at: http://link.springer.com/journal/11032, Artificially induced translocation stocks have been used to physically map the barley genome; however, natural translocations are extremely uncommon in cultivated genotypes. Albacete is a barley variety widely grown in recent decades in Spain and carrying a reciprocal translocation which obviously does not affect its agronomical fitness. This translocation has been characterized by a combination of cytological and molecular genetic approaches. Firstly, recombination frequencies between markers on chromosomes 1H and 3H were estimated to determine the boundaries of the reciprocal interchange. Secondly, 1H-3H wheat barley telosome addition lines were used to assign selected markers to chromosome arms. Thirdly, fluorescence in situ hybridization (FISH) with rDNA probes (5S and 18S-5.8S-26S) and microsatellite probes [(ACT)5, (AAG)5 and (CAG)5] was used to determine the locations of the translocation breakpoints more precisely. Fourthly, fine-mapping of the regions around the translocation breakpoints was used to increase the marker density for comparative genomics. The results obtained in this study indicate that the translocation is quite large with breakpoints located on the long arms of chromosomes 1H and 3H, between the pericentromeric (AAG)5 bands and above the (ACT)5 interstitial distal bands, resulting in the reciprocal translocation 1HS.1HL-3HL and 3HS.3HL-1HL. The gene content around the translocation breakpoints could be inferred from syntenic relationships observed among different species from the grass family Poaceae (rice, Sorghum and Brachypodium) and was estimated at approximately 1,100 and 710 gene models for 1H and 3H, respectively. Duplicated segments between chromosomes Os01 and Os05 in rice derived from ancestral duplications within the grass family overlap with the translocation breakpoints on chromosomes 1H and 3H in the barley variety Albacete., This study has been supported by the Spanish Ministry of Science and Innovation (Project AGL2008-05541-C02 and the Agrogenomics CONSOLIDER Center).