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The article offers information on a study which examined extended-spectrum β-lactamases in German Salmonella enterica isolate subsp. enterica serovar Typhimurium 4,[5],12:i:-European clone. Nine strains of German Salmonella enterica were examined for the presence of β-lactams. Study authors found that the strains share the resistance phenotype ampicillin/cefalotin/cefuroxime/ticarcillin/piperacillin/ceftiofur/ceftriaxone/cefotaxime/aztreonam/cefopodoxime.

Objectives Detection and characterization of extended-spectrum β-lactamases (ESBLs) and AmpC-encoding genes was conducted in German Salmonella isolated from different sources from 2003 to 2007. Methods Non-duplicate German isolates from the National Salmonella Reference Laboratory Collection (2003–07) with ceftiofur MICs of ≥4 mg/L were tested for β-lactam/β-lactamase inhibitor susceptibility, presence of ESBLs or AmpC-encoding genes, class 1 and 2 integrons, other resistance genes, and IS26 and ISEcp1 sequences by PCR/sequencing. The isoelectric point of the β-lactamase was determined. Strains were analysed by PFGE and plasmid profiling. The bla genes were mapped by Southern-blot hybridization. Plasmids were characterized by rep-PCR typing. Results Sixteen isolates (10 Salmonella Typhimurium, 2 Salmonella Anatum, 2 Salmonella Paratyphi B dT , 1 Salmonella Infantis and 1 Salmonella London) carried blaCTX-M (15 blaCTX-M-1 and one blaCTX-M-15) genes located on self-transferable IncB/O, IncI1 and/or IncN plasmids. Seven of the Salmonella Typhimurium isolates carried the SGI1-M variant. Six isolates (five Salmonella Agona and one Salmonella Kentucky) carried the blaCMY-2 gene on IncI1 conjugative plasmids. blaTEM-20 genes were detected in two Salmonella Paratyphi B dT isolates, and blaTEM-52 in one Salmonella Paratyphi B dT and one Salmonella Virchow, located on IncI1 plasmids. All Salmonella Paratyphi isolates harboured a 2300 bp/dfrA1-sat2-aadA1 class 2 integron. Conclusions Among the 22 679 German Salmonella isolates investigated, the ESBL and AmpC β-lactamase prevalence was still low; however, it is slowly increasing. Various β-lactamase genes are linked to a variety of genetic elements capable of horizontal DNA transfer. Consequently, their dissemination is likely and demands adequate risk management strategies. [ABSTRACT FROM AUTHOR]

Animal derived food is a relevant source of human infections with Salmonella enterica. In this paper we analyse the presence of Salmonella in meat with respect to the observed serovars and their resistance to the fluoroquinolone ciprofloxacin and 3rd generation cephalosporins in the years 2003 to 2012. Data originated from 8176 isolates that were isolated from meat, characterized in the National Reference Laboratory for Salmonella and tested for antimicrobial resistance in the National Reference Laboratory for antimicrobial resistance in this time period. The analysis reveals substantial differences in resistance patterns between isolates from different types of meat and different serovars. Frequent serovars were mostly associated with one type of meat, suggesting an additional influence of specific characteristics of the serovars besides the effect of selection pressure excerted by antimicrobial treatments. Results show a clear increase in resistance to fluoroquinolones and 3rd generation cephalosporins that was most prominent in isolates from poultry meat. Although the number of human infections with Salmonella in Germany decreased sharply in recent years, results indicate a substantial exposure of consumers to Salmonella that are resistant to important antimicrobials via meat.

Salmonella enterica subsp. enterica serovar 4,[5],12:i:- is a monophasic variant of Salmonella Typhimurium. In this study, a total of 651 human and 107 food and environmental isolates of serovar 4,[5],12:i:- recovered from 2007 through 2011 in Switzerland were characterized by antibiotic resistance profiles and pulsed-field gel electrophoresis (PFGE). In addition, a selection of isolates belonging to the most frequent PFGE patterns was further subjected to multilocus variable-number tandem-repeat analysis (MLVA) and phage typing. Over the years 2007-2011, the reports of salmonellosis caused by Salmonella enterica serovar 4,[5],12:i:- significantly increased. A high prevalence of multidrug-resistant isolates, mainly showing an ampicillin-streptomycin-sulfonamide-tetracycline resistance pattern (ASSuT), was observed. In addition, four extended spectrum beta lactamase (ESBL) (CTX-M-55)-producing isolates were found. XbaI PFGE analysis of all isolates revealed over 150 different pulsotypes, and generally showed a considerable diversity within the monophasic isolates. Nevertheless, among these we identified seven dominant profiles, which encompassed 66% of all isolates tested. The PFGE type STYMXB.0131 dominated among human as well as food isolates. Multilocus variable-number tandem-repeat analysis profile 3-12-10-0-0211, which, in many cases, coincided with PFGE type STYMXB.0131 and phage type DT193 were the most prevalent types found for the isolates further characterized by these typing methods. Our data provide strong evidence for a spread of two specific Salmonella serovar 4,[5],12:i:- clones (PFGE pattern STYMXB.0131, resistance type ASSuT) and (PFGE pattern STYMXB.0131, resistance type SSuT). In contrast to the human isolates, the pork/poultry isolates expressed predominantly the SSuT resistance type.

Salmonella enterica serovar Infantis (Salmonella Infantis) is consistently isolated from broiler chickens, pigs, and humans worldwide. This study investigated 93 epidemiologically unrelated Salmonella Infantis strains isolated in Germany between 2005 and 2008 in respect to their transmission along the food chain. Various phenotypic and genotypic methods were applied, and the pathogenicity and resistance gene repertoire was determined. Phenotypically, 66% of the strains were susceptible to all 17 antimicrobials tested, while the others were almost all multidrug-resistant (two or more antimicrobial resistances), with different resistance profiles and preferentially isolated from broiler chickens. A number of phage types (PTs) were shared by strains from pigs, broiler chickens, and humans (predominated by PT 29). One, PT 1, was only detected in strains from pigs/pork and humans. Pulsed-field gel electrophoresis (PFGE) subdivided strains in seven different clusters, named A-G, consisting of 35 various XbaI profiles with coefficient of similarity values of 0.73-0.97. The majority of XbaI profiles were assigned to clusters A and C, and two predominant XbaI profiles were common in strains isolated from all sources investigated. Multi-locus sequence typing (MLST) analysis of selected strains representing the seven PFGE clusters revealed that they all belonged to ST32. The pathogenicity gene repertoire of 37 representative Salmonella Infantis strains analyzed by microarray was also identical. The resistance gene repertoire correlated perfectly with the phenotypic antimicrobial resistance profiles, and multidrug-resistant strains were associated with class 1 integrons. Overall, this study showed that two major closely related genotypes of Salmonella Infantis can transmit in Germany to humans through contaminated broiler meat or pork, and consequently presents a hazard for human health.

In recent years in France, England, Wales, Denmark and the USA about 500 human infections occurred, which were caused by multidrug-resistant Salmonella enterica Serovar (S.) Kentucky isolates displaying high-level resistance to fluoroquinolones (ciprofloxacin, MIC > or = 4 mg/l). The responsible clone was referred to as ST198-X1.To determine whether this clone is also present in German S. Kentucky isolates, the National Reference Laboratory for Salmonella (NRL-Salm) at the BfR analyzed the trend of S. Kentucky isolates received over the past years. Since 2010 the first entries of highly ciprofloxacin resistant S. Kentucky isolates, especially from turkey meat products, were recorded. 15 isolates originating from animal or food as well as one human isolate displayed MIC values of > or = 8 mg/l to ciprofloxacin. Molecular biological typing methods showed the in Germany isolated S. Kentucky isolates to be identical to the clone described by Le Hello et al. (2011) and to carry a multidrug resistance conferring region (SGI1). Since fluoroquinolones are considered by the WHO in human and veterinary medicine as drugs of critical importance, this trend demands attention. The implementation of mitigation strategies for this highly resistant clone seems to be required.

This study was conducted to elucidate the accuracy of the current streptomycin epidemiological cut-off value (ECOFF) for Escherichia coli and Salmonella spp. A total of 236 Salmonella enterica and 208 E. coli isolates exhibiting MICs between 4 and 32 mg/L were selected from 12 countries. Isolates were investigated by polymerase chain reaction for aadA, strA, and strB streptomycin resistance genes. Out of 236 Salmonella isolates, 32 (13.5%) yielded amplicons for aadA (n = 23), strA (n = 9), and strB (n = 11). None of the 60 Salmonella isolates exhibiting MIC 4 mg/L harbored resistance genes. Of the Salmonella isolates exhibiting MICs 8 mg/L, 16 mg/L, and 32 mg/L, 1.6%, 15%, and 39%, respectively, tested positive for one or more genes. For most monitoring programs, the streptomycin ECOFF for Salmonella is wild type (WT) ≤32 or ≤16 mg/L. A cut-off value of WT ≤32 mg/L would have misclassified 13.5% of the strains as belonging to the WT population, since this proportion of strains harbored resistance genes and exhibited MICs ≤32 mg/L. Out of 208 E. coli strains, 80 (38.5%) tested positive for aadA (n = 69), strA (n = 18), and strB (n = 31). Of the E. coli isolates exhibiting MICs of 4 mg/L, 8 mg/L, 16 mg/L, and 32 mg/L, 3.6%, 17.6%, 53%, and 82.3%, respectively, harbored any of the three genes. Based on the European Committee on Antimicrobial Susceptibility Testing guidelines (ECOFF ≤16 mg/L), 25% of the E. coli strains presenting MIC ≤16 mg/L would have been incorrectly categorized as belonging to the WT population. The authors recommend an ECOFF value of WT ≤16 mg/L for Salmonella and WT ≤8 mg/L for E. coli.

The present report deals with Salmonella strains received at the German National Reference Laboratory for Salmonella (NRL-Salm) for routine diagnostic in the year 2009. Hence, the working group continues the previous report from Friedrich et al. (2010) about the documentation on the serovar distribution of Salmonella received at the NRL-Salm in the years 2004-2008. As in the recent years, most of the Salmonella strains originated from livestock and food. In the year 2009 the NRL-Salm received 4765 isolates, most of them (85,1 %) were routine diagnostic. Salmonella ser. Typhimurium, its monophasic variant S. enterica subspecies enterica serovar 1,4,[5],12:i:- and Salmonella ser. Enteritidis were the most prevalent serovars. The number of S. enterica subsp. enterica serovar 1,4,[5],12:i:- isolates increased in 2009, in comparison to the years 2004-2008, and became the second most prevalent serovar serotyped at the NRL-Salm.

The German National Reference Laboratory for Salmonella receives Salmonella isolates from diverse laboratories in Germany. Most of the Salmonella strains originated from livestock and food.This report summarizes the studies of the German National Reference Laboratory on the prevalence of Salmonella ssp. in livestock, food and feed for the years 2004-2008. In the past five years, the National Reference Laboratory received 23,949 Salmonella isolates with S. enterica serovar Typhimurium and S. enterica serovar Enteritidis as the most prevalent serovars. In addition, we summarize the incidence of emerging serovars, such as S. enterica serovar Paratyphi B (d-tartrate positive), the monophasic variant of S. enterica serovar Typhimurium (S. enterica subspecies (subsp.) enterica serovar 1,4,[5],12:i:-) and S. enterica subsp. enterica serovar 1,4,12:d:-.

In the last two years The National Salmonella Reference Laboratory (NRL-Salm) received an accumulating number of salmonellae with sero-formula 4,12:-:1,2 isolated from perished wild birds, particularly siskins. Within these strains flagellar antigen of the first phase was phenotypically not detectable. By PCR a fragment could be amplified coding specifically for the H:i-flagellar antigen. Consequently, this is a phenotypically monophasic variant of Salmonella enterica subsp. enterica serovar Typhimurium var. copenhagen with the sero-formula 4,12:-:1,2. Phage-typing showed most of the isolates belonged to phage type DT40. Some other strains harboured the same lysis pattern but could not assign to a definite phage type. Those strains are designated as RDNC (react with phages but does not conform with definite or provisorial types). Pulsed field gel-electrophoresis (PFGE) confirmed those two lineages of the monophasic variant. Phage type DT40 isolates from humans or cats, able to express both flagellar antigens, did not differ in genotypic properties from those not able to express the flagellar antigen of the first phase. Salmonella strains with identical genotypic characteristics have been isolated from wild birds, human cases particular infants and also cats. This refers to a direct or indirect transmission of the pathogen from wild bird to human. By eating or getting in contact with contaminated birds domestic cats could play an important role as vehicle between bird and human.

The Directive 2003/99/EG of the European Parliament and of the Council on the monitoring of zoonoses and zoonotic agents demands a quality management (QM) system for the execution of its monitoring programmes. Consequently the National Salmonella Reference Laboratory of Germany performed two ring-trials in 2005 and 2006 on the microbiological detection of Salmonella from poultry feces among all participating laboratories in the Federal States. Salmonella detection was performed according to the EN ISO 6579:2002 standard method which was modified according to the recommendations of the Community Reference Laboratory for Salmonella in Bilthoven, The Netherlands. This method uses modified-semisolid Rappaport-Vassiliadis Agar as the only selective enrichment. In 2005 twenty-four and in 2006 twenty-two laboratories participated. They received eight identical samples of the contamination levels L0 (no Salmonella), L1 (11 and 16 cfu per 10 g faeces respectively) and L2 (292 and 418 cfu per 10 g faeces respectively). For both years the data of 20 laboratories could statistically be evaluated. The relative accuracy of the respected results increased from 88.8% in 2005 to 98% in 2006. This is as well reflected in the improved COR- and Kappa-Indices. Taken all together the data show, that the modified-semisolid Rappaport-Vassiliadis protocol is a sensitive, established method for the detection of Salmonella from poultry faeces.

Context: Mutations in PPARG are associated with insulin resistance and familial partial lipodystrophy, a disease characterized by altered distribution of sc fat and symptoms of the metabolic syndrome. The encoded protein, peroxisome proliferator-activated receptor (PPAR)-gamma, plays a pivotal role in regulating lipid and glucose metabolism, the differentiation of adipocytes, and other cellular regulatory processes., Objectives: The objective of the study was to detect a novel PPARG mutation in a kindred with partial lipodystrophy and analyze the functional characteristics of the mutant protein., Patients and Methods: In three subjects with partial lipodystrophy, one unaffected family member, and 124 unaffected subjects, PPARG was screened for mutations by direct sequencing. Body composition, laboratory abnormalities, and hepatic steatosis were assessed in each affected subject. Transcriptional activity was determined, and EMSA was performed to investigate DNA binding capacity of the mutant protein., Results: We identified a PPARG mutation, C190S, causing partial lipodystrophy with metabolic alterations in three affected family members. The mutation was absent in the unaffected family member and unaffected controls. The mutation is located within zinc-finger 2 of the DNA binding domain. C190S PPARgamma has a significantly lower ability to activate a reporter gene than wild-type PPARgamma in absence and presence of rosiglitazone. A dominant-negative effect was not observed. Compared with wild-type PPARgamma, C190S PPARgamma shows a reduced capacity to bind DNA., Conclusion: Mutation of a zinc-binding amino acid of PPARgamma leads to an altered protein-DNA binding pattern, resulting in a partial loss of function, which in turn is associated with partial lipodystrophy.