Objectives: We assessed the efficacy and safety of an oral antimicrobial regimen for short- and long-term intestinal eradication of ESBL-producing Escherichia coli and Klebsiella pneumoniae (ESBL-EC/KP) in immunocompromised patients.
Methods: We performed a randomized (2:1), double-blind multicentre Phase II study in four haematology-oncology departments. Patients colonized with ESBL-EC/KP received a 7 day antimicrobial regimen of oral colistin (2 × 106 IU 4×/day), gentamicin (80 mg 4×/day) and fosfomycin (three administrations of 3 g every 72 h), or placebo.
In recent years an increasing number of methicillin-resistant S. pseudintermedius (MRSP) has been observed in both, healthy and clinically infected dogs. The aim of the study was the characterisation of MRSP isolates from clinical routine diagnostics of a German laboratory in order to assess the abundancy of resistance genes and SCCmec elements.
View Article and Find Full Text PDFThe presence of the methicillin resistance gene mecC in coagulase-negative Staphylococcus spp. (CoNS) is scarce. The aim of this study was to characterize mecC-positive CoNS isolated from various wild and domestic animals.
View Article and Find Full Text PDFPyrazinamide (PZA) is a key antibiotic for the treatment of drug susceptible tuberculosis. PZA-resistance is mainly mediated by mutations in the pncA gene; however the current gold standard is a phenotypic drug susceptibility test requiring a well-adjusted pH-value for reliable results. Our melting curve assay detects a non-wild type genotype in selected pncA regions in at least 3750 gene copies/mL within 2.
View Article and Find Full Text PDFThis study investigated the recent emergence of multidrug-resistant Panton-Valentine leukocidin (PVL)-negative CC1-MRSA-IV in Ireland and Germany. Ten CC1-MSSA and 139 CC1-MRSA isolates recovered in Ireland between 2004 and 2017 were investigated. These were compared to 21 German CC1-MRSA, 10 Romanian CC1-MSSA, five Romanian CC1-MRSA and two UAE CC1-MRSA, which were selected from an extensive global database, based on similar DNA microarray profiles to the Irish isolates.
View Article and Find Full Text PDFAim: A newly designed multiplex real-time PCR (rt-PCR) was validated to detect four clinically relevant Gram-negative bacteria (Escherichia coli, Acinetobacter baumannii, Klebsiella pneumoniae and Pseudomonas aeruginosa).
Materials & Methods: Serial dilutions of genomic DNA were used to determine the limit of detection. Colony PCR was performed with isolates of the four selected species and other species as negative controls.
ST239-MRSA-III is probably the oldest truly pandemic MRSA strain, circulating in many countries since the 1970s. It is still frequently isolated in some parts of the world although it has been replaced by other MRSA strains in, e.g.
View Article and Find Full Text PDFFrom 2009 to 2011 [transmission period (TP) 1] and 2014 to 2017 (TP2), two outbreaks involving community-associated clonal complex (CC) 88-MRSA types t186 and t786, respectively, occurred in the Neonatal Intensive Care Unit (NICU) of an Irish hospital (H1). This study investigated the relatedness of these isolates, their relationship to other CC88 MRSA from Ireland and their likely geographic origin, using whole-genome sequencing (WGS). All 28 CC88-MRSA isolates identified at the Irish National MRSA Reference Laboratory between 2009 and 2017 were investigated including 20 H1 patient isolates, two H1 isolates recovered from a single healthcare worker (HCW) 2 years apart, three patient isolates from a second hospital (H2) and one patient isolate from each of three different hospitals (H3, H4, and H5).
View Article and Find Full Text PDFAim: A DNA microarray-based assay for the detection of antimicrobial resistance (AMR) genes was used to study carbapenemase-producing organisms at the Kidney Center of Rawalpindi, Pakistan.
Methods: The evaluation of this assay was performed using 97 reference strains with confirmed AMR genes. Testing of 7857 clinical samples identified 425 Gram-negative bacteria out of which 82 appeared carbapenem resistant.
The most common livestock-associated lineage of methicillin-resistant Staphylococcus aureus (MRSA) in Western Europe is currently clonal complex (CC) 398. CC398-MRSA spread extensively across livestock populations in several Western European countries, and livestock-derived CC398-MRSA strains can also be detected in humans. Based on their SCCmec elements, different CC398 strains can be distinguished.
View Article and Find Full Text PDFThe rapid and robust identification of mutations in complex (MTBC) strains mediating multidrug-resistant (MDR) and extensively drug-resistant (XDR) phenotypes is crucial to combating the MDR tuberculosis (TB) epidemic. Currently available molecular anti-TB drug susceptibility tests either are restricted to a single target or drug (i.e.
View Article and Find Full Text PDFObjective: ATCC25923 is a Staphylococcus aureus strain that is positive for the Panton Valentin leukocidin. It has been used for decades as reference strain. We observed that two separately maintained clones of ATCC25923 ("G477 and G478") differed grossly in the expression of this toxin.
View Article and Find Full Text PDFPurpose: Methicillin resistant CC15 strains (CC15-MRSA) have only been sporadically described in literature. This study was carried out to describe the genetic make-up for this rare MRSA strain.
Methods: Four CC15-MRSA isolates collected in Riyadh, Saudi Arabia, between 2013 and 2014 were studied.
Single nucleotide polymorphisms (SNPs) are essential parameters in molecular diagnostics and can be used for the early detection and clinical prognosis in various diseases. Available methods for SNP detection are still labor-intensive and require a complex laboratory infrastructure, which are not suitable for the usage in resource-limited settings. Thus, there is an urgent need for a simple, reliable and rapid approach.
View Article and Find Full Text PDFThe secretion of antimicrobial compounds is an ancient mechanism with clear survival benefits for microbes competing with other microorganisms. Consequently, mechanisms that confer resistance are also ancient and may represent an underestimated reservoir in environmental bacteria. In this context, β-lactamases (BLs) are of great interest due to their long-term presence and diversification in the hospital environment, leading to the emergence of Gram-negative pathogens that are resistant to cephalosporins (extended spectrum BLs = ESBLs) and carbapenems (carbapenemases).
View Article and Find Full Text PDFSCCmec elements are very important mobile genetic elements in Staphylococci that carry beta-lactam resistance genes mecA/mecC, recombinase genes and a variety of accessory genes. Twelve main types and a couple of variants have yet been described. In addition, there are also other SCC elements harbouring other markers.
View Article and Find Full Text PDFBetween 1 August and 6 September 2013, an outbreak of Legionnaires' disease (LD) with 78 cases confirmed by positive urinary antigen tests occurred in Warstein, North Rhine-Westphalia, Germany. Legionella (L.) pneumophila, serogroup (Sg) 1, monoclonal antibody (mAb) subgroup Knoxville, sequence type (ST) 345, was identified as the epidemic strain.
View Article and Find Full Text PDFA West Australian methicillin-resistant Staphylococcus aureus strain (WA MRSA-59) was characterized by microarray and sequencing. Its pseudo-staphylococcal cassette chromosome mec (SCCmec) element comprised dcs, Q9XB68-dcs, mvaS-SCC, Q5HJW6, dru, ugpQ, ydeM, mecA-mecR-mecI, txbi mecI, tnp IS431, copA2-mco (copper resistance), ydhK, arsC-arsB-arsR (arsenic resistance), open reading frame PT43, and per-2. Recombinase genes, xylR (mecR2), and PSM-mec (phenol-soluble modulin) were absent.
View Article and Find Full Text PDFBackground: Clostridium difficile can cause antibiotic-associated diarrhea and a possibility of outbreaks in hospital settings warrants molecular typing. A microarray was designed that included toxin genes (tcdA/B, cdtA/B), genes related to antimicrobial resistance, the slpA gene and additional variable genes.
Results: DNA of six reference strains and 234 clinical isolates from South-Western and Eastern Germany was subjected to linear amplification and labeling with dUTP-linked biotin.
Typing of healthcare-associated methicillin-resistant Staphylococcus aureus (MRSA) from Australia in the 1970s revealed a novel clone, ST2249-MRSA-III (CC45), present from 1973 to 1979. This clone was present before the Australian epidemic caused by the recombinant clone, ST239-MRSA-III. This study aimed to characterize the genome of ST2249-MRSA-III to establish its relationship to other MRSA clones.
View Article and Find Full Text PDFThis study presents a DNA microarray-based assay for fast and simple PCR ribotyping of Clostridium difficile strains. Hybridization probes were designed to query the modularly structured intergenic spacer region (ISR), which is also the template for conventional and PCR ribotyping with subsequent capillary gel electrophoresis (seq-PCR) ribotyping. The probes were derived from sequences available in GenBank as well as from theoretical ISR module combinations.
View Article and Find Full Text PDFStreptococcus agalactiae frequently colonizes the urogenital tract, and it is a major cause of bacterial septicemia, meningitis, and pneumonia in newborns. For typing purposes, a microarray targeting group B streptococcus (GBS) virulence-associated markers and resistance genes was designed and validated with reference strains, as well as clinical and veterinary isolates. Selected isolates were also subjected to multilocus sequence typing.
View Article and Find Full Text PDFRapid molecular identification of carbapenemase genes in Gram-negative bacteria is crucial for infection control and prevention, surveillance and for epidemiological purposes. Furthermore, it may have a significant impact upon determining the appropriate initial treatment and greatly benefit for critically ill patients. A novel oligonucleotide microarray-based assay was developed to simultaneously detect genes encoding clinically important carbapenemases as well as selected extended (ESBL) and narrow spectrum (NSBL) beta-lactamases directly from clonal culture material within few hours.
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