Fluoroquinolone antibiotic users select fluoroquinolone-resistant ESBL-producing Enterobacteriaceae (ESBL-PE) - Data of a prospective traveller study

Background: One third of travellers to the poor regions of the (sub) tropics become colonized by extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-PE). Co-resistance to non-betalactam antibiotics complicates the treatment of potential ESBL-PE infections. Methods: We analysed co-resistance to non-beta-lactams among travel-acquired ESBL-PE isolates of 90 visitors to the (sub) tropics with respect to major risk factors of colonization: destination, age, travellers' diarrhoea (TD) and antibiotic (AB) use. Results: Of the ESBL-PE isolates, 53%, 52%, 73%, and 2% proved co-resistant to ciprofloxacin, tobramycin, co-trimoxazole, and nitrofurantoin, respectively. The rates were similar among those with (TD+) or without (TD-) travellers' diarrhoea. Among fluoroquinolone-users vs. AB non-users, the co-resistance rates for ciprofloxacin were 95% versus 37% (p = 0.001), for tobramycin 85% versus 43% (p = 0.005), co-trimoxazole 85% versus 68% (p = 0.146), and nitrofurantoin 5% versus 2% (p = 0.147). In multivariable analysis co-resistance to ciprofloxacin was associated with increasing age, fluoroquinolone use, and tobramycin resistance. Conlusions: While TD predisposes to ESBL-PE non-selectively, antimicrobial use favours strains resistant to drug taken and, simultaneously, any drug with resistance genetically linked to the drug used. Antibiotics taken during travel predispose to ESBL-PE with a high co-resistance rate. (C) 2017 The Author(s). Published by Elsevier Ltd.Peer reviewe

Travellers' diarrhoea : Impact of TD definition and control group design on study results

AbstractBackground Travellers' diarrhoea (TD) is a common health problem among visitors to the (sub)tropics. Much research deals with aetiology, prevention, and post-infection sequalae, yet the data may not allow comparisons due to incompatible definitions of TD and No TD control groups. Method The impact of defining TD and No TD control groups was explored by revisiting our recent data. We set up two TD groups: classical TD i.e. ≥3 loose or liquid stools/day and WHO TD (diarrhoea as defined by the WHO) i.e. any diarrhoea, and four No TD groups by TD definition and timing (no classical/WHO TD during travel, no ongoing classical/WHO TD). Results TD was recorded for 37% versus 65% of subjects when using classical versus WHO definitions, respectively; the proportions of the various pathogens proved similar. The strictest criterion for the No TD control group (no WHO TD during travel) yielded pathogens among 61% and the least strict (no ongoing classical TD) among 73% of the travellers; the differences were greatest for enteroaggregative Escherichia coli and Campylobacter. Conclusions Definition of TD and control group design substantially impact on TD study results. The WHO definition yields more cases, but the pathogen selection is similar by both definitions. Design of the No TD control group was found critical: only those remaining asymptomatic throughout the journey should be included.Peer reviewe

A simple magnetoencephalographic auditory paradigm may aid in confirming left-hemispheric language dominance in epilepsy patients

Objective The intracarotid amobarbital procedure (IAP) is the current "gold standard" in the preoperative assessment of language lateralization in epilepsy surgery candidates. It is, however, invasive and has several limitations. Here we tested a simple noninvasive language lateralization test performed with magnetoencephalography (MEG). Methods We recorded auditory MEG responses to pairs of vowels and pure tones in 16 epilepsy surgery candidates who had undergone IAP. For each individual, we selected the pair of planar gradiometer sensors with the strongest N100m response to vowels in each hemisphere and -from the vector sum of signals of this gradiometer pair-calculated the vowel/tone amplitude ratio in the left (L) and right (R) hemisphere and, subsequently, the laterality index: LI = (L-R)/(L+R). In addition to the analysis using a single sensor pair, an alternative analysis was performed using averaged responses over 18 temporal sensor pairs in both hemispheres. Results The laterality index did not correlate significantly with the lateralization data obtained from the IAP. However, an MEG pattern of stronger responses to vowels than tones in the left hemisphere and stronger responses to tones than vowels in the right hemisphere was associated with left-hemispheric language dominance in the IAP in all the six patients who showed this pattern. This results in a specificity of 100% and a sensitivity of 67% of this MEG pattern in predicting left-hemispheric language dominance (p = 0.01, Fisher's exact test). In the analysis using averaged responses over temporal channels, one additional patient who was left-dominant in IAP showed this particular MEG pattern, increasing the sensitivity to 78% (p = 0.003). Significance This simple MEG paradigm shows promise in feasibly and noninvasively confirming left-hemispheric language dominance in epilepsy surgery candidates. It may aid in reducing the need for the IAP, if the results are confirmed in larger patient samples.Peer reviewe

Evaluation of High-Throughput PCR and Microarray-Based Assay in Conjunction with Automated DNA Extraction Instruments for Diagnosis of Sepsis

BACKGROUND: High incidence of septic patients increases the pressure of faster and more reliable bacterial identification methods to adapt patient management towards focused and effective treatment options. The aim of this study was to assess two automated DNA extraction solutions with the PCR and microarray-based assay to enable rapid and reliable detection and speciation of causative agents in the diagnosis of sepsis. METHODOLOGY/PRINCIPAL FINDINGS: We evaluated two automated DNA instruments NucliSENS® easyMAG® and NorDiag Arrow for the preparation of blood culture samples. A set of 91 samples flagged as positive during incubation was analyzed prospectively with the high-throughput generation of Prove-it™ Sepsis assay designed to identify over 60 gram-negative and gram-positive bacterial species as well as methicillin resistance marker from a blood culture. Bacterial findings were accurately reported from 77 blood culture samples, whereas 14 samples were reported as negative, containing bacteria not belonging to the pathogen panel of the assay. No difference was observed between the performance of NorDiag Arrow or NucliSENS® easyMAG® with regard to the result reporting of Prove-it™ Sepsis. In addition, we also assessed the quality and quantity of DNA extracted from the clinical Escherichia coli isolate with DNA extraction instruments. We observed only minor differences between the two instruments. CONCLUSIONS: Use of automated and standardized sample preparation methods together with rapid, multiplex pathogen detection offers a strategy to speed up reliably the diagnostics of septic patients. Both tested DNA extraction devices were shown to be feasible for blood culture samples and the Prove-it™ Sepsis assay, providing an accurate identification of pathogen within 4.5 hours when the detected pathogen was in the repertoire of the test

Despite antibiotic treatment of travellers' diarrhoea pathogens are found in stools from half of travellers at return

Background: Among visitors to the (sub)tropics, 20-50% contract travellers' diarrhoea (TD) and 5-30% take antibiotics. While shortening the duration of illness, antimicrobials predispose to acquisition of multi-drug resistant bacteria. Therefore, liberal use is no longer advocated. Although antibiotics kill pathogens, no data support the view that they could prevent post-infectious sequelae. We investigated how antibiotic use for TD abroad impacts the pathogen findings at return. Materials and methods: We revisited 456 travellers' clinical data and stool pathogens examined by qPCR for Salmonella, Yersinia, Campylobacter, Shigella, Vibrio cholerae and enteroaggregative (EAEC), enteropathogenic (EPEC), enterotoxigenic (ETEC), enterohaemorrhagic (EHEC) and enteroinvasive (EIEC) Escherichia coli. Results: Among travellers with TD, antibiotic users had pathogen-positive samples less frequently than non-users (50% versus 83%). The difference was significant for EPEC (23% versus 47%) and EAEC (27% versus 54%), but not ETEC (17% versus 26%) or the other pathogens. Shigella/EIEC was found more often among antibiotic users than non-users (4% versus 1%). Conclusion: Despite antibiotic treatment of TD, half of the users still had stool pathogens at return, reflecting either antibiotic resistance of pathogens or recolonisation/reinfection while abroad. Treatment of TD with antibiotics during travel should not be interpreted to indicate eradication of pathogens.Peer reviewe

A prospective study of travellers' diarrhoea : analysis of pathogen findings by destination in various (sub)tropical regions

Objectives: Eighty million travellers visiting (sub)tropical regions contract travellers' diarrhoea (TD) each year, yet prospective data comparing the prevalence of TD pathogens in various geographical regions are scarce. Our recent study using modern molecular methods found enteropathogenic (EPEC) and enteroaggregative (EAEC) Escherichia coli to be the most frequent pathogens, followed by enterotoxigenic E. coli (ETEC) and Campylobacter. We revisited our data to compare the findings by geographical region. Methods: A total of 459 prospectively recruited travellers provided stool samples and completed questionnaires before and after visiting destinations in various geographical regions. A multiplex quantitative real-time PCR assay was used to analyse Salmonella, Yersinia, Campylobacter jejuni/Campylobacter coli, Shigella, Vibrio cholerae, EPEC, EAEC, ETEC, enterohaemorrhagic E. coli and enteroinvasive E. coli. Results: TD was contracted by 69% (316/459) of the subjects; EPEC and EAEC outnumbered ETEC and Campylobacter in all regions. Multiple pathogens were detected in 42% (133/316) of the samples. The proportions of all pathogens varied by region. The greatest differences were seen for Campylobacter: while relatively frequent in South Asia (n = 11; 20% of the 55 with TD during travel) and Southeast Asia (15/84, 15%), it was less common in East and West Africa (5/71, 7% and 1/57, 2%) and absent in South America and the Caribbean (0/40). Conclusions: EPEC and EAEC outnumbered ETEC and Campylobacter everywhere, yet the proportions of pathogen findings varied by region, with ETEC and Campylobacter rates showing the greatest differences. The high frequency of multibacterial findings in many regions indicates a need for further investigation of the clinical role of each pathogen. (C) 2017 The Authors. Published by Elsevier Ltd on behalf of European Society of Clinical Microbiology and Infectious Diseases.Peer reviewe

Interictal magnetoencephalography in parietal lobe epilepsy – comparison of equivalent current dipole and beamformer (SAMepi) analysis

Objective To evaluate a novel analysis method (SAMepi) in the localization of interictal epileptiform magnetoencephalographic (MEG) activity in parietal lobe epilepsy (PLE) patients in comparison with equivalent current dipole (ECD) analysis. Methods We analyzed the preoperative interictal MEG of 17 operated PLE patients utilizing visual analysis and: (1) ECD with a spherical conductor model; (2) ECD with a boundary element method (BEM) conductor model; and (3) SAMepi - a kurtosis beamformer method. Localization results were compared between the three methods, to the location of the resection and to the clinical outcome. Results Fourteen patients had an epileptiform finding in the visual analysis; SAMepi detected spikes in 11 of them. A unifocal finding in both the ECD and in the SAMepi analysis was associated with a better chance of seizure-freedom (p=0.02). There was no significant difference in the distances from the unifocal MEG localizations to the nearest border of the resection between the different analysis methods. Conclusions Localizations of unifocal interictal spikes detected by SAMepi did not significantly differ from the conventional ECD localizations. Significance SAMepi - a novel semiautomatic analysis method - is useful in localizing interictal epileptiform MEG activity in the presurgical evaluation of parietal lobe epilepsy patients.Peer reviewe

Wastewater Surveillance Detected Carbapenemase Enzymes in Clinically Relevant Gram-Negative Bacteria in Helsinki, Finland; 2011-2012

Antimicrobial resistance profiling of pathogens helps to identify the emergence of rare or new resistance threats and prioritize possible actions to be taken against them. The analysis of wastewater (WW) can reveal the circulation of antimicrobial-resistant bacteria (ARB) and antimicrobial resistance genes (ARG) among the catchment communities. Here, we analyzed WW influent samples to determine the prevalence of carbapenemase genes-carrying Gram-negative bacteria (Carba-GNB) in Helsinki, Finland. This study set important historical reference points from the very early stage of the carbapenemase era, during the period 2011-2012. A total of 405 bacterial isolates grown on CHROMagarKPC (n = 195) and CHROMagarESBL (n = 210) from WW influent samples were collected between October 2011 and August 2012 and were analyzed. The bacterial DNA from the isolates was extracted, and the prevalence of carbapenemases genes bla(KPC), bla(NDM), bla(GES), bla(OXA-48), bla(IMP), bla(IMI), and bla(VIM) were screened with multiplexed PCR. All carbapenemase-positive isolates were identified taxonomically to species or genus level with matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). The nucleic acid extraction was successful for 399 isolates, of which 59 (14.8%) were found to carry carbapenemase genes. A total of 89.8% of the carbapenemase positive isolates (53 out of 59) were obtained from CHROMagarKPC plates and only 10.2% (six out of 59) were obtained from CHROMagar ESBL plates. Among the Carba-GNB isolates, 86.4% were bla(GES) (51 out of 59), 10.2% were bla(KPC) (six out of 59), and 3.4% were bla(VIM) (two out of 59). The most common carba-gene, bla(GES), was carried by 10 different bacterial species, including Aeromonas spp., Enterobacter spp., and Kluyvera spp.; the bla(KPC) gene was carried by Escherichia coli, Klebsiella pneumoniae, and Kluyvera cryocescens; and the bla(VIM) gene was carried by Aeromonas hydrophila/caviae and Citrobacter amalonaticus. This study emphasizes that wastewater surveillance (WWS) can be an additional tool for monitoring antimicrobial resistance (AMR) at the population level.Peer reviewe

Increased Risk for ESBL-Producing Bacteria from Co-administration of Loperamide and Antimicrobial Drugs for Travelers' Diarrhea

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Multiplex PCR detection of Cryptosporidium sp, Giardia lamblia and Entamoeba histolytica directly from dried stool samples from Guinea-Bissauan children with diarrhoea

Background: In developing countries, diarrhoea is the most common cause of death for children under five years of age, with Giardia lamblia, Cryptosporidium and Entamoeba histolytica as the most frequent pathogenic parasites. Traditional microscopy for stool parasites has poor sensitivity and specificity, while new molecular methods may provide more accurate diagnostics. In poor regions with sample storage hampered by uncertain electricity supply, research would benefit from a method capable of analysing dried stools. Methods: A real-time multiplex PCR method with internal inhibition control was developed for detecting Giardia lamblia, Cryptosporidium hominis/parvum and Entamoeba histolytica directly from stool specimens. Applicability to dried samples was checked by comparing with fresh ones in a small test material. Finally, the assay was applied to dried specimens collected from Guinea-Bissauan children with diarrhoea. Results: The PCR's analytical sensitivity limit was 0.1 ng/ml for G. lamblia DNA, 0.01 ng/ml for E. histolytica DNA and 0.1 ng/ml for Cryptosporidium sp. In the test material, the assay performed similarly with fresh and dried stools. Of the 52 Guinea-Bissauan samples, local microscopy revealed a parasite in 15%, while PCR detected 62% positive for at least one parasite: 44% of the dried samples had Giardia, 23% Cryptosporidium and 0% E. histolytica. Conclusions: Our new multiplex real-time PCR for protozoa presents a sensitive method applicable to dried samples. As proof of concept, it worked well on stools collected from Guinea-Bissauan children with diarrhoea. It provides an epidemiological tool for analysing dried specimens from regions poor in resources.Peer reviewe