Objective Our aim was to prospectively assess the antibiotic resistance rates in Helicobacter pylori strains in Europe in 2018 and to study the link between antibiotic consumption in the community and H. pylori resistance levels in the different countries. Design The proportion of primary antibiotic resistance cases of H. pylori and their corresponding risk factors were investigated in 24 centres from 18 European countries according to a standardised protocol. Data on antibiotic consumption in the community were collected for the period 2008–2017. The link between antibiotic consumption and resistance data was assessed using generalised linear mixed models. The model with the best fit was selected by means of the Akaike Information Criterion. Results H. pylori resistance rates for the 1211 adult patients included were 21.4% for clarithromycin, 15.8% for levofloxacin and 38.9% for metronidazole and were significantly higher in Central/Western and Southern than in the Northern European countries. The best model fit was obtained for the Poisson distribution using 2013 consumption data. A significant association was found between H. pylori clarithromycin resistance and consumption in the community of macrolides (p=0.0003) and intermediate-acting macrolides (p=0.005), and between levofloxacin resistance and consumption of quinolones (p=0.0002) and second-generation quinolones (p=0.0003). Conclusion This study confirms the positive correlation between macrolide and quinolone consumption in the community and corresponding H. pylori resistance in European countries. Hence, H. pylori treatment with clarithromycin and levofloxacin should not be started without susceptibility testing in most European countries.
The incidence of nosocomial infections due to carbapenem-resistant Klebsiella pneumoniae is increasing worldwide. Whole-genome sequencing (WGS) can help elucidate the transmission route of nosocomial pathogens.We combined WGS and epidemiological data to analyze an outbreak of New Delhi metallo-β-lactamase (NDM)-producing K. pneumoniae that occurred in 2 Belgian hospitals situated about 50 miles apart. We characterized 74 NDM-producing K. pneumoniae isolates (9 from hospital A, 24 from hospital B, and 41 contemporary isolates from 15 other Belgian hospitals) using pulsed-field gel electrophoresis and WGS.A K. pneumoniae sequence type 716 clone was identified as being responsible for the outbreak with all 9 strains from hospital A and 20 of 24 from hospital B sharing a unique pulsotype and being clustered together at WGS (compared with 1 of 41 isolates from other Belgian hospitals). We identified the outpatient clinic of hospital B as the probable bridging site between the hospitals after combining epidemiological, phylogenetic, and resistome data. We also identified the patient who probably caused the transmission. In fact, all but 1 strain from hospital A carried a Tn1331-like transposon, whereas none of the hospital B isolates did. The patient from hospital A who did not have the Tn1331-like transposon was treated at the outpatient clinic of hospital B on the same day as the first NDM-producing K. pneumoniae-positive patient from hospital B.The results from our WGS-guided investigation highlight the importance of implementing adequate infection control measures in outpatient settings, especially when healthcare delivery moves from acute care facilities to outpatient clinics.
To validate and accredit a set of three multiplex endpoint PCR assays, targeting the most important carbapenemase and minor extended-spectrum β-lactamase (ESBL) resistance genes, according to the international ISO 15189 particular requirements for the quality and competence of medical laboratories. Specific primers targeting ESBLs and carbapenemases were collected from the literature or designed internally. The multiplex PCRs were validated for sensitivity, specificity, intra- and inter-run reproducibility and accuracy by means of external quality control (EQC) using a collection of 137 characterized and referenced isolates. For each multiplex PCR assay, the presence of an extraction control ruled out false-negative results due to PCR inhibition or extraction faults. Amplicons were separated by capillary electrophoresis (QIAxcel system, Qiagen). The protocols and validation files were reviewed in the setting of an external audit conducted by the Belgian organization for accreditation (BELAC). Sensitivity, specificity and reproducibility for each targeted gene were 100%. All isolates from the three EQC panels were correctly identified by each PCR assay (accuracy 100%). The validation files were controlled by BELAC, and the PCR protocols were accepted as accredited according to ISO 15189. Three home-made multiplex PCRs targeting the major carbapenemases and four minor class A ESBL genes encountered in Gram-negative bacteria were accredited according to the ISO 15189 standards. This validation scheme could provide a useful model for laboratories aiming to accredit their own protocols.
ABSTRACT The aim of this study was to evaluate the performance of Brilliance ESBL agar (OX; Oxoid, Basingstoke, United Kingdom), a novel chromogenic agar for the selective isolation and the presumptive identification of extended-spectrum-beta-lactamase (ESBL)-producing Enterobacteriaceae . A panel of 200 clinical Gram-negative Enterobacteriaceae and nonfermenting isolates with defined resistance mechanisms was inoculated onto OX and onto ChromID ESBL agar (BM; bioMérieux, Marcy l'Etoile, France) chromogenic medium in the first part of the study to evaluate the growth selectivity and chromogenic features of these two media. Of the 156 Enterobacteriaceae challenge isolates, 8 fully susceptible isolates were inhibited, all 98 ESBL producers were detected, and 50 isolates harboring other resistance mechanisms were recovered on both chromogenic agars. In the second phase, 528 clinical samples (including 344 fecal specimens) were plated onto OX, BM, and MacConkey agar with a ceftazidime disk (MCC) for the screening of ESBL-producing Enterobacteriaceae . Growth on at least one medium was observed with 144 (27%) of the clinical samples screened. A total of 182 isolates, including 109 (60%) of Enterobacteriaceae , were recovered and 70 of these (from 59 specimens) were confirmed as ESBL-producing isolates. The sensitivities of MCC, BM, and OX were 74.6%, 94.9%, and 94.9%, respectively. The specificities of MCC, BM, and OX by specimens reached 94.9%, 95.5%, and 95.7%, respectively, when only colored colonies were considered on the two selective chromogenic media. The high negative predictive value (99.3%) found for OX suggests that this medium may constitute an excellent screening tool for the rapid exclusion of patients not carrying ESBL producers.
Background: Invasive aspergillosis (IA) is a significant cause of morbidity and mortality in patients with haematological malignancies. Accurate diagnosis of IA is challenging due to non-specific symptoms and the impact of antifungal prophylaxis on biomarker sensitivity. Methods: This retrospective study evaluated the diagnostic performance of three serum biomarkers: Aspergillus Galactomannan Ag VirClia Monotest® (VirClia), Wako β-D-Glucan Test® (Wako BDG), and MycoGENIE Real-Time PCR® (MycoGENIE PCR). True positives were defined as patients with proven or probable IA (n = 14), with a positive Platelia Aspergillus Antigen® (Platelia) serving as a mycological criterion. True negatives were identified as patients with a positive Platelia assay but classified as non-probable IA (n = 10) and outpatients who consistently tested negative with the Platelia test throughout the study period (n = 20). Results: Most patients diagnosed with proven or probable IA were acute myeloid leukaemia or myelodysplastic syndrome patients receiving mould-active antifungal prophylaxis or treatment (71%). VirClia demonstrated high sensitivity (100%) for detecting IA, with a specificity of 83%. Wako BDG and MycoGENIE PCR showed lower sensitivities for IA (57% and 64%, respectively). MycoGENIE PCR detected Aspergillus spp. and Mucorales in two patients. Conclusions: Accurate diagnosis of IA remains challenging, especially in patients who have received mould-active antifungal treatment. VirClia showed comparable performance to Platelia, suggesting its potential for routine use. However, Wako BDG and MycoGENIE PCR results were less favourable in our study cohort. Nevertheless, MycoGENIE PCR detected two probable co-infections with Aspergillus spp. and Mucorales.
During a PCR-based surveillance study of β-lactam resistance, 125 multidrug-resistant (MDR) Acinetobacter baumannii isolates were obtained from 18 hospitals in Belgium from January 2008 to December 2009. Nine GES-positive A. baumannii isolates were detected at 6 Belgian hospitals. DNA sequencing of the bla(GES) genes identified GES-11, GES-12, and a novel variant GES-14, which differs from GES-11 by a single amino acid substitution (Gly170Ser). All index isolates were travel associated and originated from patients transferred from Turkey (n = 2), Egypt (n = 2), and Palestinian territories (Gaza) (n = 2). A nosocomial outbreak involving three additional patients occurred in a burn unit at a single hospital. No clonal relatedness could be established between the 6 index isolates by pulsed-field gel electrophoresis (PFGE) analysis. Three different alleles (the plasmid-located bla(GES-11) and bla(GES-12) and a likely chromosomally located novel variant bla(GES-14)) were detected as part of a class 1 integron, also including the aac6'Ib and dfrA7 genes. Restriction analysis of plasmids suggests a common origin for the plasmids bearing bla(GES-11) and bla(GES-12). Cloning of the bla(GES) genes in Escherichia coli identified GES-14 as hydrolyzing imipenem, while GES-12 showed the highest specific activity against ceftazidime. This report highlights the emergence of various bla(GES-like) genes, especially those conferring carbapenem resistance in A. baumannii and its importation in Western Europe from Middle Eastern countries.
Carbapenemase-producing Pseudomonadaceae have increasingly been reported worldwide, with an ever-increasing heterogeneity of carbapenem resistance mechanisms, depending on the bacterial species and the geographical location. OXA-198 is a plasmid-encoded class D β-lactamase involved in carbapenem resistance in one Pseudomonas aeruginosa isolate from Belgium. In the setting of a multicenter survey of carbapenem resistance in P. aeruginosa strains in Belgian hospitals in 2013, three additional OXA-198-producing P. aeruginosa isolates originating from patients hospitalized in one hospital were detected. To reveal the molecular mechanism underlying the reduced susceptibility to carbapenems, MIC determinations, whole-genome sequencing, and PCR analyses to confirm the genetic organization were performed. The plasmid harboring the blaOXA-198 gene was characterized, along with the genetic relatedness of the four P. aeruginosa isolates. The blaOXA-198 gene was harbored on a class 1 integron carried by an ∼49-kb IncP-type plasmid proposed as IncP-11. The same plasmid was present in all four P. aeruginosa isolates. Multilocus sequence typing revealed that the isolates all belonged to sequence type 446, and single-nucleotide polymorphism analysis revealed only a few differences between the isolates. This report describes the structure of a 49-kb plasmid harboring the blaOXA-198 gene and presents the first description of OXA-198-producing P. aeruginosa isolates associated with a hospital-associated cluster episode.
