Impact of minimal invasive extracorporeal circulation on perioperative intravenous fluid management in coronary artery bypass surgery.

OBJECTIVE: Compare the use of blood products and intravenous fluid management in patients scheduled for coronary artery bypass surgery and randomized to minimal invasive extracorporeal circulation (MiECC) and conventional extracorporeal circulation (CECC). METHODS: A total of 240 patients who were scheduled for their first on-pump CABG, were randomized to MiECC or CECC groups. The study period was the first 84 hours after surgery. Hemoglobin <80 g/l was used as transfusion trigger. RESULTS: Red blood cell transfusions intraoperatively were given less often in the MiECC group (23.3% vs 9.2%, p = 0.005) and the total intravenous fluid intake was significantly lower in the MiECC group (3300 ml [2950-4000] vs 4800 ml [4000-5500], p < 0.001). Hemoglobin drop also was lower in the MiECC group (35.5 ± 8.9 g/l vs 50.7 ± 9 g/l, p < 0.001) as was hemoglobin drop percent (25.3 ± 6% vs 35.3 ± 5.9%, p < 0.001). Chest tube drainage output was higher in the MiECC group (645 ml [500-917.5] vs 550 ml [412.5-750], p = 0.001). Particularly, chest tube drainage in up to 600 ml category, was in benefit of CECC group (59.1% vs 40.8%, p = 0.003). ROC curve analysis showed that patients with hemoglobin level below 95 g/l upon arrival to intensive care unit was associated with increased risk of developing postoperative atrial fibrillation (POAF) (p = 0.002, auc = 0.61, cutoff <95, sensitivity = 0.47, positive predictive value = 0.64). CONCLUSION: MiECC reduced the intraoperative need for RBC transfusion and intravenous fluids compared to the CECC group, also reducing hemoglobin drop compared to the CECC group in CABG surgery patients. Postoperative hemoglobin drop was a predictor of POAF.

Low prevalence of livestock-associated methicillin-resistant Staphylococcus aureus clonal complex 398 and mecC MRSA among human isolates in North-West England.

AIMS: Livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) is an important public health problem in many countries. Despite reports of such isolates being found in both animals and humans in the United Kingdom few data are available on the prevalence in humans of such isolates. A prevalence study was therefore undertaken in the north-west of England. METHODS AND RESULTS: One thousand two hundred and forty-two human MRSA isolates collected during 2015 were screened by PCR to detect two of the major forms of LA-MRSA: clonal complex (CC)398 and mecC MRSA. Isolates identified were further characterized by antimicrobial susceptibility testing and whole-genome sequencing using HiSeq technology. A single mecC MRSA isolate and three CC398 LA-MRSA were identified among the isolates screened. All four isolates were from MRSA screening. A phylogenetic analysis, including previously sequenced isolates from the United Kingdom, provided strong evidence for the genomic and epidemiological linkage between a pair of animal and human isolates of CC398 LA-MRSA in England. These data are indicative of animal and humans isolates of CC398 LA-MRSA being involved in the same transmission network and is the first demonstration of such closely linked animal and human isolates of this lineage in the UK. CONCLUSIONS: The study indicates there is a low prevalence of CC398 LA-MRSA and mecC MRSA among MRSA isolates in the sampled population. SIGNIFICANCE AND IMPACT OF THE STUDY: While the study demonstrates that LA-MRSA were rare among human MRSA isolates in the sampled population, the data provide a baseline for the future surveillance of what is a significant public health challenge in some regions. The demonstration of linked human and animal isolates of CC398 LA-MRSA, supported by genomic and epidemiological data, reinforces the need for such surveillance and for continued awareness of the risks that LA-MRSA may pose in the UK.

Methicillin-Resistant Staphylococcus aureus Harboring mecC Still Eludes Us in East London, United Kingdom.

Reports of methicillin-resistant Staphylococcus aureus (MRSA) harboring the mecC gene have increased in the UK since first being described. To our diagnostic S. aureus multiplex PCR, a mecC primer set was designed and implemented, and then the prevalence in our patient population was investigated. Fewer than 1% of the clinical isolates possessed the mecC gene, confirming that mecA remains the dominant genetic determinant of MRSA in East London.

Staphylococcus pseudoxylosus sp. nov., isolated from bovine mastitis.

Strain S04009T, a Gram-stain-positive, coagulase-negative staphylococcus, was isolated from bovine mastitis in France. 16S rRNA gene analysis revealed it to be closely related to the coagulase-negative species Staphylococcusxylosus, Staphylococcussaprophyticus, Staphylococcuscaeli and Staphylococcus edaphicus. At the whole-genome level, strain S04009T had an average nucleotide identity value <95 % and an inferred DNA-DNA hybridization value <70 % when compared to these species. Furthermore, phenotypic characteristics distinguished S04009T from those species. From these related species only strain S04009T and S. xylosus are able to ferment xylose and these two can be distinguished by the inability of strain S04009T to express urease activity. Based on the genotypic and phenotypic results, it is proposed that this isolate is a novel species, with the name Staphylococcus pseudoxylosus sp. nov. The type strain is S04009T (=DSM 107950T=CCUG 72763T=NCTC 14184T).

Detection of MRSA of Lineages CC130-mecC and CC398-mecA and Staphylococcus delphini-lnu(A) in Magpies and Cinereous Vultures in Spain.

The aim of this study was to determine the carriage rate of coagulase-positive staphylococci (CoPS) in wild birds and to characterize recovered isolates. Tracheal samples from 324 wild birds, obtained in different Spanish regions during 2015-2016, were screened for CoPS carriage. The antimicrobial resistance profile and the virulence gene content were investigated. Molecular typing was performed by spa, agr, MLST, SCCmec, and S. delphini group classification. CoPS were recovered from 26 samples of wild birds (8.3%), and 27 isolates were further characterized. Two CoPS species were detected: S. aureus (n = 15; eight cinereous vultures and seven magpies) and S. delphini (n = 12; 11 cinereous vultures and one red kite). Thirteen S. aureus were methicillin-resistant (MRSA) and the remaining two strains were methicillin-susceptible (MSSA). Twelve MRSA were mecC-positive, typed as t843-ST1583/ST1945/ST1581/ST1571 (n = 11) and t1535-ST1945 (n = 1) (all of clonal-complex CC130); they were susceptible to the non-ß-lactams tested. The remaining MRSA strain carried the mecA gene, was typed as t011-ST398-CC398-agrI-SCCmec-V, and showed a multiresistance phenotype. MSSA isolates were ascribed to lineages ST97-CC97 and ST425-CC425. All S. aureus lacked the studied virulence genes (lukS/F-PV, tst, eta, etb, and etd), and the IEC type E (with scn and sak genes) was detected in four mecC-positive and one MSSA isolates. S. delphini strains were methicillin-susceptible but showed resistance to at least one of the antimicrobials tested, with high penicillin (75%, with blaZ gene) and tetracycline [58%, with tet(K)± tet(L)] resistance rates. All S. delphini isolates presented the virulence genes lukS-I, siet, and se-int, and four carried the clindamycin-resistance lnu(A) gene.

Diversity of Staphylococcus aureus clones in wild mammals in Aragon, Spain, with detection of MRSA ST130-mecC in wild rabbits.

AIMS: To determine the Staphylococcus aureus carriage rate in wild mammals in Aragon, northern Spain, to analyse their antimicrobial resistance phenotype/genotype and to characterize the recovered isolates. METHODS AND RESULTS: Nasal and rectal swabs of 103 mammals were collected in Aragón during the period 2012-2015. Antimicrobial susceptibility, the presence of antimicrobial resistance genes and virulence factors were investigated. Molecular characterization was carried out by spa, MLST, agr and SCCmec. Staphylococcus aureus were recovered from 23 animals (22%). Four of the 23 S. aureus were methicillin-resistant S. aureus (MRSA). Three MRSA were mecC-positive and were isolated from European rabbits and were typed as t843 (ascribed to CC130). The remaining MRSA was a mecA-carrying isolate from European hedgehog, typed as ST1-t386-SCCmecIVa-agrIII and it harboured the blaZ, erm(C), ant(6)-Ia and aph(3´)-IIIa resistance genes. A high diversity of spa-types was detected among the 19 methicillin-susceptible S. aureus isolates, which showed high susceptibility to the antimicrobials tested. The tst gene and different combinations of staphylococcal enterotoxins were found. CONCLUSIONS: Staphylococcus aureus were detected in nasal and rectal samples of wild mammals. Wild rabbits could be a reservoir of mecC-MRSA. SIGNIFICANCE AND IMPACT OF THE STUDY: This work provides information on the presence and characteristics of S. aureus from mammals in a defined geographic region in Spain.

Comparison of Different Phenotypic Approaches To Screen and Detect mecC-Harboring Methicillin-Resistant Staphylococcus aureus.

Similar to mecA, mecC confers resistance against beta-lactams, leading to the phenotype of methicillin-resistant Staphylococcus aureus (MRSA). However, mecC-harboring MRSA strains pose special difficulties in their detection. The aim of this study was to assess and compare different phenotypic systems for screening, identification, and susceptibility testing of mecC-positive MRSA isolates. A well-characterized collection of mecC-positive S. aureus isolates (n = 111) was used for evaluation. Routinely used approaches were studied to determine their suitability to correctly identify mecC-harboring MRSA, including three (semi)automated antimicrobial susceptibility testing (AST) systems and five selective chromogenic agar plates. Additionally, a cefoxitin disk diffusion test and an oxacillin broth microdilution assay were examined. All mecC-harboring MRSA isolates were able to grow on all chromogenic MRSA screening plates tested. Detection of these isolates in AST systems based on cefoxitin and/or oxacillin testing yielded overall positive agreements with the mecC genotype of 97.3% (MicroScan WalkAway; Siemens), 91.9% (Vitek 2; bioMérieux), and 64.9% (Phoenix, BD). The phenotypic resistance pattern most frequently observed by AST devices was "cefoxitin resistance/oxacillin susceptibility," ranging from 54.1% (Phoenix) and 83.8% (Vitek 2) to 92.8% (WalkAway). The cefoxitin disk diffusion and oxacillin broth microdilution assays categorized 100% and 61.3% of isolates to be MRSA, respectively. The chromogenic media tested confirmed their suitability to reliably screen for mecC-harboring MRSA. The AST systems showed false-negative results with varying numbers, misidentifying mecC-harboring MRSA as methicillin-susceptible S. aureus This study underlines cefoxitin's status as the superior surrogate mecC-positive MRSA marker.

Wild rodents and shrews are natural hosts of Staphylococcus aureus.

Laboratory mice are the most commonly used animal model for Staphylococcus aureus infection studies. We have previously shown that laboratory mice from global vendors are frequently colonized with S. aureus. Laboratory mice originate from wild house mice. Hence, we investigated whether wild rodents, including house mice, as well as shrews are naturally colonized with S. aureus and whether S. aureus adapts to the wild animal host. 295 animals of ten different species were caught in different locations over four years (2012-2015) in Germany, France and the Czech Republic. 45 animals were positive for S. aureus (15.3%). Three animals were co-colonized with two different isolates, resulting in 48 S. aureus isolates in total. Positive animals were found in Germany and the Czech Republic in each studied year. The S. aureus isolates belonged to ten different spa types, which grouped into six lineages (clonal complex (CC) 49, CC88, CC130, CC1956, sequence type (ST) 890, ST3033). CC49 isolates were most abundant (17/48, 35.4%), followed by CC1956 (14/48, 29.2%) and ST890 (9/48, 18.8%). The wild animal isolates lacked certain properties that are common among human isolates, e.g., a phage-encoded immune evasion cluster, superantigen genes on mobile genetic elements and antibiotic resistance genes, which suggests long-term adaptation to the wild animal host. One CC130 isolate contained the mecC gene, implying wild rodents might be both reservoir and vector for methicillin-resistant . In conclusion, we demonstrated that wild rodents and shrews are naturally colonized with S. aureus, and that those S. aureus isolates show signs of host adaptation.

Full-Genome Sequencing Identifies in the Genetic Background Several Determinants That Modulate the Resistance Phenotype in Methicillin-Resistant Staphylococcus aureus Strains Carrying the Novel mecC Gene.

Most methicillin-resistant Staphylococcus aureus (MRSA) strains are resistant to beta-lactam antibiotics due to the presence of the mecA gene, encoding an extra penicillin-binding protein (PBP2A) that has low affinity for virtually all beta-lactam antibiotics. Recently, a new resistance determinant-the mecC gene-was identified in S. aureus isolates recovered from humans and dairy cattle. Although having typically low MICs to beta-lactam antibiotics, MRSA strains with the mecC determinant are also capable of expressing high levels of oxacillin resistance when in an optimal genetic background. In order to test the impact of extensive beta-lactam selection on the emergence of mecC-carrying strains with high levels of antibiotic resistance, we exposed the prototype mecC-carrying MRSA strain, LGA251, to increasing concentrations of oxacillin. LGA251 was able to rapidly adapt to high concentrations of oxacillin in growth medium. In such laboratory mutants with increased levels of oxacillin resistance, we identified mutations in genes with no relationship to the mecC regulatory system, indicating that the genetic background plays an important role in the establishment of the levels of oxacillin resistance. Our data also indicate that the stringent stress response plays a critical role in the beta-lactam antibiotic resistance phenotype of MRSA strains carrying the mecC determinant.

Short communication: ß-Lactam resistance and vancomycin heteroresistance in Staphylococcus spp. isolated from bovine subclinical mastitis.

The use of antimicrobial agents has led to the emergence of resistant bacterial strains over a relatively short period. Furthermore, Staphylococcus spp. can produce ß-lactamase, which explains the survival of these strains in a focus of infection despite the use of a ß-lactam antibiotic. The aim of this study was to evaluate the resistance of Staphylococcus spp. isolated from bovine subclinical mastitis to oxacillin and vancomycin (by minimum inhibitory concentration) and to detect vancomycin heteroresistance by a screening method. We also evaluated ß-lactamase production and resistance due to hyperproduction of this enzyme and investigated the mecA and mecC genes and performed staphylococcal cassette chromosome mec typing. For this purpose, 181 Staphylococcus spp. isolated from mastitis subclinical bovine were analyzed. Using the phenotypic method, 33 (18.2%) of Staphylococcus spp. were resistant to oxacillin. In contrast, all isolates were susceptible to vancomycin, and heteroresistance was detected by the screening method in 13 isolates. Production of ß-lactamase was observed in 174 (96%) of the Staphylococcus spp. isolates. The mecA gene was detected in 8 isolates, all of them belonging to the species Staphylococcus epidermidis, and staphylococcal cassette chromosome mec typing revealed the presence of type I and type IV isolates.

Prevalence and characterization of methicillin-resistant Staphylococcus aureus carrying mecA or mecC and methicillin-susceptible Staphylococcus aureus in dairy sheep farms in central Italy.

Between January and May 2012, a total of 286 bulk tank milk samples from dairy sheep farms located in central Italy were tested for the presence of Staphylococcus aureus. One hundred fifty-three samples were positive for S. aureus (53.5%), with an average count of 2.53 log cfu/mL. A total of 679 S. aureus colonies were screened for methicillin resistance by the cefoxitin disk diffusion test, and 104 selected cefoxitin-susceptible isolates were also tested for their susceptibility to other antimicrobials representative of the most relevant classes active against Staphylococcus spp. by using the Kirby-Bauer disk diffusion method. Two methicillin-resistant Staphylococcus aureus (MRSA) isolates, carrying respectively the mecA and the mecC genes, were detected in 2 samples from 2 different farms (prevalence 0.7%). The mecA-positive MRSA isolate was blaZ positive, belonged to spa type t127, sequence type (ST)1, clonal complex (CC)1, carried a staphylococcal cassette chromosome mec (SCCmec) type IVa, and was phenotypically resistant to all the ß-lactams tested and to erythromycin, streptomycin, kanamycin, and tetracycline. The mecC-positive MRSA isolate was negative for the chromosomally or plasmid-associated blaZ gene but positive for the blaZ allotype associated with SCCmec XI (blaZ-SCCmecXI), belonged to spa type 843, ST(CC)130, carried a SCCmec type XI, and was resistant only to ß-lactams. Both MRSA were negative for the presence of specific immune-evasion and virulence genes such as those coding for the Panton-Valentine leucocidin, the toxic shock syndrome toxin 1, and the immune evasion cluster genes. Regarding the presence of the major S. aureus enterotoxin genes, the mecC-positive MRSA tested negative, whereas the ST (CC)1 mecA-positive MRSA harbored the seh gene. Among the 104 methicillin-susceptible S. aureus isolates examined for antimicrobial susceptibility, 63 (60.58%) were susceptible to all the antimicrobials tested, and 41 (39.42%) were resistant to at least 1 antimicrobial. In particular, 23 isolates (22.12%) were resistant to tetracycline, 16 (15.38%) to sulfonomides, 14 (13.46%) to trimethoprim and sulfamethoxazole, and 9 (8.65%) to ampicillin, whereas only 1 isolate was resistant to both fluoroquinolones and aminoglycosides. The high prevalence of S. aureus found in bulk tank milk samples and the isolation of MRSA, although at a low prevalence, underlines the importance of adopting control measures against S. aureus in dairy sheep farms to minimize the risks for animal and public health. Moreover, this study represents the first report of mecC-positive MRSA isolation in Italy and would confirm that, among livestock animals, sheep might act as a mecC-MRSA reservoir. Although this lineage seems to be rare in dairy sheep (0.35% of farms tested), because mecC-positive MRSA are difficult to detect by diagnostic routine methods employed for mecA-positive livestock-associated MRSA, diagnostic laboratories should be aware of the importance of searching for the mecC gene in all the mecA-negative S. aureus isolates displaying resistance to oxacillin, cefoxitin, or both.

Molecular characterization of Staphylococcus aureus isolated from humans related to a livestock farm in Spain, with detection of MRSA-CC130 carrying mecC gene: A zoonotic case?

OBJECTIVES: To conduct a study of Staphylococcus aureus carriage in members of a livestock-farmer's family with different degrees of animal contact, and to characterize the recovered isolates. METHODS: Nasal samples from 11 members of the family were taken in three sampling periods (every six months) (n=31), and 9 skin samples from superficial lesions were also obtained in 5 of them. Samples were analyzed for S. aureus susceptible (MSSA) and resistant to methicillin (MRSA). S. aureus isolates were tested for antibiotic-resistance phenotype and genotype and for the detection of virulence and IEC-system genes. Molecular typing of isolates was also performed (spa- and multilocus-sequence typing). RESULTS: Eighteen S. aureus isolates were recovered (1 MRSA and 17 MSSA) in the 40 samples analyzed. S. aureus was detected in nasal and skin samples of 7/11 and 4/5 of tested humans, respectively. The MRSA strain was detected in the skin lesion of a farmer with high animal contact, and carried the mecC gene, and was typed as ST130-CC130-t843. The 17 MSSA isolates were ascribed to 9 different spa-types and sequence types included in the clonal complexes CC22, CC30, CC45, CC121, and in the livestock-associated lineages CC9 and CC133. Six strains harbored eta or tsst-1 genes. Three of 18 strains lacked the immune-evasion-cluster (IEC) genes (MRSA-ST130, MSSA-ST1333, and MSSA-ST133), and the remaining isolates were ascribed to IEC type-A or -B. CONCLUSIONS: Animal-associated S. aureus lineages were detected in samples of the farmer's family, highlighting the detection of MSSA-CC133 and mecC-MRSA-ST130.

Survey of community-associated-methicillin-Resistant Staphylococcus aureus in Slovenia: identification of community-associated and livestock-associated clones.

The epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) in Slovenia is poorly documented. The aim of this study was to investigate susceptibility patterns, virulence gene profile and clonality among MRSA isolates with positive screened resistance phenotype for CA-MRSA collected from patients in Slovenia, from January 2010 to December 2010. We included only MRSA isolates that were resistant to cefoxitin and oxacillin, and susceptible to at least two of the following four antibiotics: ciprofloxacin, erythromycin, clindamycin or gentamicin (presumptive CA-MRSA). Altogether 151 isolates fulfilled our screening phenotypic definition, 126 MRSA isolates were classified as CA-MRSA and 25 as HA-MRSA. Thirty-six per cent of them were resistant to ciprofloxacin, 24% to clindamycin, 33% to erythromycin and 13% to gentamicin. The mecA gene was detected in 150 isolates, while the mecC gene only in 1 isolate. The MRSA isolates were classified to 19 different clones. The most prevalent sequence types were ST5 (26.4%), ST45 (25.2%), ST22 (10.6%), ST398 (9.9%), ST8 (5.9%), ST7 (4.6%), ST1 (3.9%), ST152/377 (3.3%), ST228 (2.6%) and ST2883 (1.3%). The ST6, ST9, ST30, ST72, ST88, ST111, ST130, ST225 and ST772 were identified sporadically. The Panton-Valentine leukocidin (PVL) gene was detected in 13 (8.6%) isolates that belonged to ST5, ST7, ST8, ST22, ST72, ST88, ST 152/377 and ST772. Our results show high variability of CA-MRSA circulating in Slovenia and also the presence of LA-MRSA clones.

Novel mutations in penicillin-binding protein genes in clinical Staphylococcus aureus isolates that are methicillin resistant on susceptibility testing, but lack the mec gene.

OBJECTIVES: Methicillin-resistant Staphylococcus aureus (MRSA) is an important global health problem. MRSA resistance to ß-lactam antibiotics is mediated by the mecA or mecC genes, which encode an alternative penicillin-binding protein (PBP) 2a that has a low affinity to ß-lactam antibiotics. Detection of mec genes or PBP2a is regarded as the gold standard for the diagnosis of MRSA. We identified four MRSA isolates that lacked mecA or mecC genes, but were still phenotypically resistant to pencillinase-resistant ß-lactam antibiotics. METHODS: The four human S. aureus isolates were investigated by whole genome sequencing and a range of phenotypic assays. RESULTS: We identified a number of amino acid substitutions present in the endogenous PBPs 1, 2 and 3 that were found in the resistant isolates but were absent in closely related susceptible isolates and which may be the basis of resistance. Of particular interest are three identical amino acid substitutions in PBPs 1, 2 and 3, occurring independently in isolates from at least two separate multilocus sequence types. Two different non-conservative substitutions were also present in the same amino acid of PBP1 in two isolates from two different sequence types. CONCLUSIONS: This work suggests that phenotypically resistant MRSA could be misdiagnosed using molecular methods alone and provides evidence of alternative mechanisms for ß-lactam resistance in MRSA that may need to be considered by diagnostic laboratories.

Methicillin resistance in Staphylococcus isolates: the "mec alphabet" with specific consideration of mecC, a mec homolog associated with zoonotic S. aureus lineages.

Livestock-associated (LA) methicillin-resistant Staphylococcus aureus (MRSA) have globally emerged during the past decade. In Europe, this was particularly due to the occurrence of LA-MRSA strains associated with the clonal complex (CC) 398 as defined by multilocus sequence typing. However, more recently animal-adapted clonal lineages of S. aureus showing phenotypic methicillin resistance have been identified such as CC130, CC599, CC59, CC1943 and CC425. These newly emerging LA-MRSA CCs/STs caused infections in animals and zoonoses in humans. In contrast to other S. aureus clonal lineages, the methicillin resistance of the latter CCs/STs is based on a mecA gene homolog, designated mecC, which is part of a distinct SCCmec type (SCCmec XI). Including mecB found in Macrococcus caseolyticus, henceforth, the "mec alphabet" comprises three major gene types with several allotypes. As known for mecA, the gene homolog mecC is also not restricted to S. aureus, but found in several staphylococcal species including S. sciuri, S. stepanovicii and S. xylosus (mecC1 allotype). First investigations showed a wide geographical distribution of mecC-MRSA in Europe and a broad diversity of host species including livestock, companion and wildlife animals. In particular, wild rodents and insectivores might serve as reservoir for staphylococci harboring mecC. Economic burden may be caused by mastitis of dairy cattle. Livestock animals may likely serve as source for human infections with mecC-MRSA; reported cases comprise skin and soft tissue infections, osteomyelitis and bacteremia. Due to the divergent molecular nature of mecC-MRSA, its diagnostics is hampered by difficulties to verify the methicillin resistance using phenotypic as well as DNA-based procedures, which could have negative consequences for therapy of mecC-MRSA-caused infections.

Multiple cases of methicillin-resistant CC130 Staphylococcus aureus harboring mecC in milk and swab samples from a Bavarian dairy herd.

The discovery of a new mecA homolog, mecC, necessitates a modification of diagnostic procedures for the identification of methicillin-resistant Staphylococcus aureus (MRSA), as most assays used for the genotypic and phenotypic mecA detection cannot currently recognize mecC. Although the prevalence, distribution, and importance of mecC are not yet completely understood, an exchange of mecC-MRSA between humans and animals seems possible. All previously reported observations of mecC-positive strains have been sporadic. To the best of our knowledge, this is the first report about multiple cases of mecC-positive Staph. aureus in 1 dairy herd. Clonal complex 130 Staph. aureus harboring mecC were found in milk samples from 16 of 56 lactating cows kept in a herd in Bavaria, Germany. Almost all quarter milk samples positive for mecC-MRSA had the lowest possible California Mastitis Test score; composite somatic cell counts obtained from monthly milk recordings showed a mean of 51,600 cells/mL in mecC-MRSA affected cows. Additionally, mecC-positive clonal complex 130 Staph. aureus were detected in swab samples from the mammary skin and a teat lesion of 1 cow from this herd. This report suggests that mecC-carrying strains are able to spread among livestock, and that they have the ability to cause multiple cases in single herds. Therefore, future studies targeting MRSA in dairy cows need to consider mecC.

[Antimicrobial spectrum of ceftaroline. In vitro activity against methicillin-resistant staphylococci]. / Espectro antimicrobiano de ceftarolina. Actividad in vitro frente a estafilococos resistentes a la meticilina.

Because of the increase in bacterial resistance, there is a need for new antimicrobial agents. In particular, Staphylococcus aureus is a frequent cause of severe infections and has an extraordinary capacity to develop antibiotic multiresistance, including resistance to glycopeptides, linezolid, and daptomycin. Although the incidence of methicillin-resistant S. aureus (MRSA) seems to have stabilized in the last few years, its wide dissemination in healthcare settings and in the community is a cause of concern. Ceftaroline is a new broad-spectrum cephalosporin with bactericidal activity against Gram-positive bacteria, including MRSA and multidrug-resistant Streptococcus pneumoniae. In addition, this drug is active against staphylococci showing resistance to glycopeptides, linezolid, and daptomycin. The ceftaroline MIC90 against MRSA ranges from 0.5-2mg/L and that against methicillin-resistant coagulase-negative staphylococci is 0.5mg/L. Ceftaroline has also good activity against respiratory pathogens including Haemophilus influenzae and Moraxella catarrhalis. Although this drug is active against Enterobacteriaceae, it does not retain activity when these isolates produce extended-spectrum beta-lactamases, carbapenemases or hyperproduce AmpC. Ceftaroline is not active against nonfermentative Gram-negative bacilli. Ceftaroline is an interesting addition to the therapeutic armamentarium against MRSA and constitutes an important option for the treatment of polymicrobial infections caused by multidrug-resistant Gram-positive microorganisms.

Minimal extracorporeal circulation (MECC) does not result in less hypertrophic scar formation as compared to conventional extracorporeal circulation (CECC) with dexamethasone.

INTRODUCTION: Cardiopulmonary bypass surgery is associated with a systemic inflammatory response through the interaction of air, blood and synthetic components in the bypass system and the physical trauma of surgery. An alternative cardiopulmonary bypass system, minimal extracorporeal circulation (MECC), has shown promising results in terms of reducing the inflammatory response. We hypothesized that this system may reduce pathological excessive scarring. To study this assumption, the effects of MECC and the effects of conventional extracorporeal circulation (CECC) with dexamethasone on skin scarring were compared in a standardized wound-healing model. METHODS AND RESULTS: Pre-sternal scars were evaluated prospectively at four and 12 months postoperatively. The height and width of the scars were measured, using a slide caliper and sonography. The scars were scored using the validated Patient and Observer Scar Assessment Scale. Additional risk factors for hypertrophic scar formation were identified by means of a questionnaire. During surgery, MECC was used in 45 patients and CECC/dexamethasone in 42 patients. Four months postoperatively, 22 patients of the MECC group (49%) and 18 patients in the CECC/dexamethasone group (43%) had developed hypertrophic scars. Twelve months postoperatively, the hypertrophic scars in four patients of the MECC group and in two patients of the CECC/dexamethasone group had become normotrophic. In 18 patients of the MECC group (38%) and 16 patients of the CECC group (41%) the scars remained hypertrophic at 12 months. These differences between the two groups were not statistically significant. CONCLUSION: MECC does not reduce hypertrophic scar formation compared with CECC with dexamethasone, but its use is more beneficial than the use of CECC/dexamethasone because of the circulatory and immunological advantages and because treatment with dexamethasone can be omitted.

Genomic epidemiology of mecC-carrying Staphylococcus aureus isolates from human clinical cases in New Zealand.

In 2011, a novel methicillin resistance gene, mecC, was described in human and bovine Staphylococcus aureus isolates. mecC-positive S. aureus is most commonly associated with livestock and wildlife populations across Europe and is particularly prevalent in hedgehogs, but only occasionally causes human infections. In this study, we characterize and investigate the origin of two human S. aureus isolates containing mecC genes from New Zealand. The two isolates were identified from patients with severe invasion infections as part of an S. aureus bacteraemia study. Whole-genome sequencing was used to characterize staphylococcal cassette chromosome mec (SCCmec) elements and perform phylogenetic comparisons with publicly available strains from mecC-associated clonal complexes, including isolates from hedgehogs from New Zealand and Europe/United Kingdom (UK), and livestock, wildlife and human isolates from Europe/UK. The two isolates from our study have almost identical SCCmec type XI elements containing a mecC gene. However, this gene contains a premature stop codon, consistent with the methicillin-susceptible phenotype observed for these isolates. Core genome SNP analyses showed that the two isolates are 234 SNPs apart and are most closely related to an isolate obtained from a New Zealand hedgehog. However, there are considerable differences in the mecC mobile element between the human and hedgehog isolates, indicating the presence of an as-yet-unknown reservoir of mecC S. aureus in the New Zealand environment.