Jacques Schrenzel - Academia.edu (original) (raw)
Papers by Jacques Schrenzel
Revue médicale suisse, 2014
Carbapenemase-producing enterobacteria (CPE) spread all over the world during the last years, cau... more Carbapenemase-producing enterobacteria (CPE) spread all over the world during the last years, causing serious infections with increasing frequency. Very few new drugs active against CPE are expected to be clinically available. Studies summarized in this review show that there is yet room to improve our therapeutic approaches, in the treatment of infections due to CPE.
Intensive Care Medicine Experimental, Jun 23, 2023
PubMed, Oct 10, 2018
In the last decade, the epidemiology of meningococcal infections in Switzerland and Europe has ch... more In the last decade, the epidemiology of meningococcal infections in Switzerland and Europe has changed. The prevalence of Y and W serogroups augmented, with more atypical clinical manifestations such as pharyngitis, pneumonia and arthritis. A hypervirulent clonal serogroup W strain of Neisseria meningitidis has emerged in Europe and Switzerland, with a noticeable potential for epidemics as evidenced by its clonality. In this context, vaccinal recommendations for risk groups have and will continue to evolve towards the use of novel conjugated vaccines.
European Journal of Clinical Microbiology & Infectious Diseases, May 24, 2020
Capnocytophaga canis is an uncommon cause of septic shock. Only three cases have been previously ... more Capnocytophaga canis is an uncommon cause of septic shock. Only three cases have been previously reported in the literature. In this article, we describe the case of a 70-year-old male admitted to the intensive care unit for septic shock of unknown origin. On day 2, one anaerobic bottle out of the two sets taken at admission turned positive with Gram-negative bacilli. The pathogen was identified by 16S rRNA gene as C. canis. The strain was characterized and compared with other clinical isolates of Capnocytophaga spp.
Frontiers in Microbiology, Nov 24, 2020
Swiss NGS-Based S. aureus Proficiency Test information, was similar across pipelines for closely ... more Swiss NGS-Based S. aureus Proficiency Test information, was similar across pipelines for closely related strains when restricting SNP calls to a common core genome defined by S. aureus cgMLST schema. The lessons learned from this pilot study will serve the implementation of larger-scale RT, as a mean to have regular external quality assessments for laboratories performing WGS analyses in a clinical setting.
Revue médicale suisse, 2014
Pneumonia is an importance cause of mortality and morbidity in adults. Two types of pneumonia are... more Pneumonia is an importance cause of mortality and morbidity in adults. Two types of pneumonia are defined: community-acquired and nosocomial pneumonia with their corresponding etiology such as pneumococci or Haemophilus influenzae and Pseudomonas or enterobacteriaceae, respectively. However, the reality is more complex with aspiration pneumonia, pneumonia in immunocompromised patient, and pneumonia in ventilated patients. Culture in the case of nosocomial pneumonia is especially important to obtain the antibiotic susceptibility of the infectious agent and to adjust therapy. Moreover for immunocompromised patients, the differential diagnosis is much wider looking for viruses, filamentous fungi and Pneumocystis can be very informative, using new molecular assays.
HAL (Le Centre pour la Communication Scientifique Directe), Jan 12, 2016
International audienc
Revue médicale suisse, 2014
Due to overuse, we are about to reach the end of the antibiotic era. Each of us is responsible to... more Due to overuse, we are about to reach the end of the antibiotic era. Each of us is responsible to limit their usage to a minimum. Respiratory infections are the first cause of antibiotic prescriptions. The use of new simple tests available at the bedside can be very useful in this context. The development of sophisticated molecular diagnostic tools, such as "multiorganism" panels, may revolutionize our approach to respiratory infections. The key will be to interpret the results correctly, with due consideration of the statement, "Treat patients, not lab results".
Swiss medical forum =, Nov 14, 2018
* Die Mitglieder des Steuerungsausschusses von anresis.ch sowie die mit anresis.ch verbundenen La... more * Die Mitglieder des Steuerungsausschusses von anresis.ch sowie die mit anresis.ch verbundenen Laboratorien sind am Schluss des Artikels aufgeführt. Die Mortalität und Morbidität infolge Infektionen mit multiresistenten Keimen steigen an und beschränken sich nicht mehr nur auf gefährdete Bevölkerungs gruppen. Daneben stellt insbesondere auch die Kolonisation asymptomatischer Patienten mit multiresistenten Keimen ein relevantes Problem dar. Antibiotikaresistenzen nehmen weltweit zu Gemäss dem «European Centre for Disease Prevention and Control» (ECDC) starben allein in den Ländern der Europäischen Union 2007 zirka 25 000 Menschen an Infektionen mit resistenten Bakterien [1], und gemäss Hochrechnungen werden bis 2050 mit jährlich zehn Millionen Todesfällen mehr Personen an multiresis tenten 1 Erregern (inkl. der multiresistenten Tuberku lose) als an Karzinomen versterben [2]. Neben der erhöhten Mortalität führen Infektionen mit multiresistenten Erregern zu höheren Kosten auf grund längerer Hospitalisationsdauer, aufwendiger Isolationsmassnahmen und komplexerer antibioti scher Therapien mit Einsatz mehrerer Antibiotika und/oder teurerer Reserveantibiotika. Letztere kön nen zudem durch vermehrte Nebenwirkungen wiede rum Mortalität und Morbidität negativ beeinflussen. Besonders gefährdete Bevölkerungsgruppen sind Kin der, ältere Menschen, Personen mit Grundkrankheiten und hospitalisierte Patienten generell. Eine Auswei tung auf den ambulanten Bereich und die gesamte Be völkerung zeichnet sich jedoch ab. Die Infektionen stellen aber nur einen Teil des Pro blems dar. Noch häufiger ist die Kolonisation asym ptomatischer Patienten mit mulitresistenten Erregern. Diese sind insofern von Bedeutung, als sie einerseits zu einer Erkrankung der betreffenden Person führen und andererseits auch unbemerkt auf andere Perso nen übertragen werden können.
Microbiology resource announcements, Jan 31, 2019
Here we report the whole-genome sequences of 15 clinical Streptococcus suis strains isolated from... more Here we report the whole-genome sequences of 15 clinical Streptococcus suis strains isolated from pigs in Switzerland. Although they originated from the same host and geographic origin, the strains showed a large amount of diversity. S treptococcus suis is a Gram-positive, facultative, anaerobic bacterium that is mainly found in the nasal mucosa and the tonsils of healthy pigs. Under predisposing circumstances, like inadequate sanitation or reduced immunity, S. suis can cause various diseases such as meningitis, septicemia, arthritis, pneumonia, and endocarditis (1). Besides being an important pig pathogen causing major economic losses, S. suis is considered a relevant zoonotic agent, especially in China and Southeast Asia (1-3). Currently, there are 29 described S. suis serotypes. Worldwide, serotype 2 is the most common reported serotype to cause infections in pigs, followed by serotypes 9 and 3 (1). In humans, the most frequently identified serotypes are serotype 2, followed by serotype 14 (1). We have sequenced 15 clinical S. suis strains (Table 1). The strains were originally isolated between 2006 and 2018 by streaking pig samples onto Columbia agar with sheep blood (Thermo Fisher Diagnostics AG, Pratteln, Switzerland). The plates were incubated at 37°C for 48 hours under aerobic conditions. Strains were identified by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) (Biotyper Compass Explorer software v.4.1.60, Bruker Daltonics, Bremen, Germany) and serotyped by multiplex PCR according to Kerdsin et al. (4). Genomic DNA was extracted using a DNA blood and tissue kit (Qiagen, Hombrechtikon, Switzerland) and prepared for sequencing with a Nextera DNA Flex sample preparation kit (Illumina, San Diego, CA, USA) on an Illumina MiniSeq sequencer with 150-bp paired-end reads. The sequencing resulted in an output of paired-end read sets containing 596,559 to 1,666,705 reads of 150 bp. The quality of the reads was checked using FastQC (https:// www.bioinformatics.babraham.ac.uk/projects/fastqc/). The reads passed all quality steps with the exception of the control step "per-base sequence content." Failure to pass this step, however, is typical for transposon-based libraries (FastQC manual [see https://www.bioinformatics.babraham.ac.uk/projects/fastqc/]) and was ignored. Reads were assembled de novo using Spades 3.12 (5) with activation of the "-careful" option. Raw assemblies were filtered for size larger than 1,000 bp and coverage of more than 25-fold. The final assemblies resulted in 13 genomes with a size between 1,878,848 and 2,135,450 bp and coverages between 50-and 120-fold (Table 1). The genomes consisted of 24 to 64 contigs per strain, and the largest contigs were 129 to 333 kbp. Strains SS1014 and PP464 had large genomes of 2,340,449 and 2,504,491 bp, with coverages of 50-and 39-fold, respectively. The SS1014 and PP464 genomes consisted of 204 and 94 contigs, the largest of which were 76 kb and 174 kb, respectively.
Pediatric Infectious Disease Journal, Apr 1, 2014
To evaluate the intrafamilial oropharyngeal transmission of Kingella kingae, we conducted a prosp... more To evaluate the intrafamilial oropharyngeal transmission of Kingella kingae, we conducted a prospective study among pairs of siblings. We found that 55% of children who suffered from osteoarticular infections due to K. kingae, and 40% of asymptomatic carriers of K. kingae had siblings with positive oropharyngeal carriage.
Fems Microbiology Reviews, Dec 12, 2016
This review discusses the role of generation of reactive oxygen species by the phagocyte NADPH ox... more This review discusses the role of generation of reactive oxygen species by the phagocyte NADPH oxidase NOX2 in host-pathogen interaction with a specific focus on S. aureus infections.
Photodiagnosis and Photodynamic Therapy, May 1, 2013
In dentistry, residual infection remains a major cause of failure after endodontic treatment; man... more In dentistry, residual infection remains a major cause of failure after endodontic treatment; many of these infections involve Enterococcus faecalis. In the current study, we explored the possibility that blue light activated photosensitizers could be used, in principle, to inactivate this microbe as an adjunct disinfection strategy for endodontic therapy. Three blue light absorbing photosensitizers, eosin-Y, rose bengal, and curcumin, were tested on E. faecalis grown in planktonic suspensions or biofilms. Photosensitizers were incubated for 30 min with bacteria then exposed to blue light (450-500 nm) for 240 s. Sodium hypochlorite (3%) was used as a control. After 48 h, the viability of E. faecalis was estimated by measuring colonyforming units post-exposure vs. untreated controls (CFU/mL). Blue light irradiation alone did not alter E. faecalis viability. For planktonic cultures, blue light activated eosin-Y (5 M), rose bengal (1 M), or curcumin (5 M) significantly (p < 0.05) reduced E. faecalis viability compared to exposure to the unirradiated photochemicals. For biofilm cultures, concentrations of lightactivated eosin-Y, rose bengal, and curcumin of 100, 10, and 10 M respectively, completely suppressed E. faecalis viability (p < 0.05). Although the current results are limited to an in vitro model, they support further exploration of blue light activated antimicrobials as an adjunct therapy in endodontic treatment.
Revue médicale suisse, 2014
Revue Médicale Suissewww.revmed.ch-12 novembre 2014 Revue Médicale Suissewww.revmed.ch-12 novembr... more Revue Médicale Suissewww.revmed.ch-12 novembre 2014 Revue Médicale Suissewww.revmed.ch-12 novembre 2014 2155 brought to you by CO metadata, citation and similar papers at core.ac.uk provided by Serveur académique lausa * à lire ** à lire absolument
Microbial genomics, May 12, 2023
The Swiss Pathogen Surveillance Platform (SPSP) is a shared secure surveillance platform between ... more The Swiss Pathogen Surveillance Platform (SPSP) is a shared secure surveillance platform between human and veterinary medicine, to also include environmental and foodborne isolates. It enables rapid and detailed transmission monitoring and outbreak surveillance of pathogens using whole genome sequencing data and associated metadata. It features controlled data access, complex dynamic queries, dedicated dashboards and automated data sharing with international repositories, providing actionable results for public health and the vision to improve societal well-being and health.
British Journal of Surgery, May 1, 2021
Objective Our objective was to describe the aetiologies of acute colitis and to identify patients... more Objective Our objective was to describe the aetiologies of acute colitis and to identify patients who require diagnostic endoscopy. Methods Patients with symptoms of gastrointestinal infection and colonic inflammation on computed tomography were prospectively included. Those immunosuppressed, with history of colorectal cancer or inflammatory bowel disease (IBD) were excluded. Stools were screened with BD-Max and BioFire FilmArray GI panel. Faecal calprotectin was determined. Patients with negative BD-Max underwent colonoscopy. The study was registered into clinicaltrials.gov (NCT02709213). Results One hundred and seventy-nine patients were included. BD-Max was positive in 93 patients (52%) and FilmArray in 108 patients (60.3%). Patients with infectious colitis (n = 103, 57.5%) were positive for Campylobacter spp (n = 57, 55.3%), Escherichia coli spp (n = 8, 7.8%), Clostridium difficile (n = 23, 22.3%), Salmonella spp (n = 9, 8.7%), viruses (n = 7, 6.8%), Shigella spp (n = 6, 5.8%), Entamoeba histolytica (n = 2, 1.9%) and others (n = 4, 3.9%). Eighty-six patients underwent colonoscopy, which was compatible with ischemic colitis in 18 patients (10.1%) and IBD in 4 patients (2.2%). Among patients with negative FilmArray, a faecal calprotectin >625μg/g allowed identifying patients with IBD with an area under ROC curve of 85.1%. Introduction of a diagnostic management algorithm including FilmArray and faecal calprotectin could allow decreasing unnecessary colonoscopies from 82 to 29 (corresponding to a decrease of 64.6%). Conclusion Computed tomography-proven colitis was mostly of infectious aetiology. Diagnostic management of patients with acute colitis should include broad molecular testing of the stools and, in patients with a calprotectin concentration >625μg/g, colonoscopy to exclude IBD.
British Journal of Surgery, May 1, 2021
Objective There is growing evidence supporting that the gut microbiota is a major driver of human... more Objective There is growing evidence supporting that the gut microbiota is a major driver of human health and disease. While gut microbiota transfer (GMT) is commonly used as an approach to restore "eubiosis", there is a surprising lack of data on whether the transferred microbiota efficiently and durably repopulate the gut of the transplanted subject. Moreover, little is known on the effects of GMT on non-alcoholic fatty liver disease (NAFLD). Methods Chronic dysbiosis and NAFLD-like liver injury were induced by feeding C57Bl/6j mice for 16 weeks with a high-fat diet. For GMT, dysbiotic mice underwent preliminary gut cleansing, followed by oral gavage with a suspension of fresh fecal matter procured from a pool of lean mice (1 dose, or 10 doses). We next characterized microbiota composition and we measured the relative abundance of specific pathobionts in recipient mice, using high-throughput shotgun analysis in a dynamic manner, over time. All experiments took place in a specific germ-free environment. Results After 4 months on a high-fat diet, mice displayed fatty liver infiltration with moderate parenchymal inflammatory changes. Dysbiosis was evidenced by a reduced bacterial diversity, as well as a dramatically increased abundance of Firmicutes, and lower Verrucomicrobia and Actinobacteria. Gut microbiota transfer was associated with a transitory reduction in NAFLD-induced hepatocellular injury. While dysbiotic mice displayed a shift in their microbiota composition towards that of lean donors after GMT, this effect rapidly faded after one week, and mice recovered their initial, dysbiotic microbiota. Conclusion The current study indicates that, when used in mice with chronically established dysbiosis, GMT is merely associated with transitory changes in gut microbiota composition, as well as significant but moderate reduction in hepatocellular injury.
Swiss medical forum =, Nov 14, 2018
Forum médical suisse =, Nov 14, 2018
Une détermination rapide et fiable des résistances aux antibiotiques est indispensable pour la mi... more Une détermination rapide et fiable des résistances aux antibiotiques est indispensable pour la mise en place d'un traitement efficace et ciblé. La surveillance de la situation des résistances livre des informations essentielles pour la détermination du traitement empirique et aide à prendre des mesures destinées à éviter une plus large propagation des bactéries résistantes aux antibiotiques.
Revue médicale suisse, 2014
Carbapenemase-producing enterobacteria (CPE) spread all over the world during the last years, cau... more Carbapenemase-producing enterobacteria (CPE) spread all over the world during the last years, causing serious infections with increasing frequency. Very few new drugs active against CPE are expected to be clinically available. Studies summarized in this review show that there is yet room to improve our therapeutic approaches, in the treatment of infections due to CPE.
Intensive Care Medicine Experimental, Jun 23, 2023
PubMed, Oct 10, 2018
In the last decade, the epidemiology of meningococcal infections in Switzerland and Europe has ch... more In the last decade, the epidemiology of meningococcal infections in Switzerland and Europe has changed. The prevalence of Y and W serogroups augmented, with more atypical clinical manifestations such as pharyngitis, pneumonia and arthritis. A hypervirulent clonal serogroup W strain of Neisseria meningitidis has emerged in Europe and Switzerland, with a noticeable potential for epidemics as evidenced by its clonality. In this context, vaccinal recommendations for risk groups have and will continue to evolve towards the use of novel conjugated vaccines.
European Journal of Clinical Microbiology & Infectious Diseases, May 24, 2020
Capnocytophaga canis is an uncommon cause of septic shock. Only three cases have been previously ... more Capnocytophaga canis is an uncommon cause of septic shock. Only three cases have been previously reported in the literature. In this article, we describe the case of a 70-year-old male admitted to the intensive care unit for septic shock of unknown origin. On day 2, one anaerobic bottle out of the two sets taken at admission turned positive with Gram-negative bacilli. The pathogen was identified by 16S rRNA gene as C. canis. The strain was characterized and compared with other clinical isolates of Capnocytophaga spp.
Frontiers in Microbiology, Nov 24, 2020
Swiss NGS-Based S. aureus Proficiency Test information, was similar across pipelines for closely ... more Swiss NGS-Based S. aureus Proficiency Test information, was similar across pipelines for closely related strains when restricting SNP calls to a common core genome defined by S. aureus cgMLST schema. The lessons learned from this pilot study will serve the implementation of larger-scale RT, as a mean to have regular external quality assessments for laboratories performing WGS analyses in a clinical setting.
Revue médicale suisse, 2014
Pneumonia is an importance cause of mortality and morbidity in adults. Two types of pneumonia are... more Pneumonia is an importance cause of mortality and morbidity in adults. Two types of pneumonia are defined: community-acquired and nosocomial pneumonia with their corresponding etiology such as pneumococci or Haemophilus influenzae and Pseudomonas or enterobacteriaceae, respectively. However, the reality is more complex with aspiration pneumonia, pneumonia in immunocompromised patient, and pneumonia in ventilated patients. Culture in the case of nosocomial pneumonia is especially important to obtain the antibiotic susceptibility of the infectious agent and to adjust therapy. Moreover for immunocompromised patients, the differential diagnosis is much wider looking for viruses, filamentous fungi and Pneumocystis can be very informative, using new molecular assays.
HAL (Le Centre pour la Communication Scientifique Directe), Jan 12, 2016
International audienc
Revue médicale suisse, 2014
Due to overuse, we are about to reach the end of the antibiotic era. Each of us is responsible to... more Due to overuse, we are about to reach the end of the antibiotic era. Each of us is responsible to limit their usage to a minimum. Respiratory infections are the first cause of antibiotic prescriptions. The use of new simple tests available at the bedside can be very useful in this context. The development of sophisticated molecular diagnostic tools, such as "multiorganism" panels, may revolutionize our approach to respiratory infections. The key will be to interpret the results correctly, with due consideration of the statement, "Treat patients, not lab results".
Swiss medical forum =, Nov 14, 2018
* Die Mitglieder des Steuerungsausschusses von anresis.ch sowie die mit anresis.ch verbundenen La... more * Die Mitglieder des Steuerungsausschusses von anresis.ch sowie die mit anresis.ch verbundenen Laboratorien sind am Schluss des Artikels aufgeführt. Die Mortalität und Morbidität infolge Infektionen mit multiresistenten Keimen steigen an und beschränken sich nicht mehr nur auf gefährdete Bevölkerungs gruppen. Daneben stellt insbesondere auch die Kolonisation asymptomatischer Patienten mit multiresistenten Keimen ein relevantes Problem dar. Antibiotikaresistenzen nehmen weltweit zu Gemäss dem «European Centre for Disease Prevention and Control» (ECDC) starben allein in den Ländern der Europäischen Union 2007 zirka 25 000 Menschen an Infektionen mit resistenten Bakterien [1], und gemäss Hochrechnungen werden bis 2050 mit jährlich zehn Millionen Todesfällen mehr Personen an multiresis tenten 1 Erregern (inkl. der multiresistenten Tuberku lose) als an Karzinomen versterben [2]. Neben der erhöhten Mortalität führen Infektionen mit multiresistenten Erregern zu höheren Kosten auf grund längerer Hospitalisationsdauer, aufwendiger Isolationsmassnahmen und komplexerer antibioti scher Therapien mit Einsatz mehrerer Antibiotika und/oder teurerer Reserveantibiotika. Letztere kön nen zudem durch vermehrte Nebenwirkungen wiede rum Mortalität und Morbidität negativ beeinflussen. Besonders gefährdete Bevölkerungsgruppen sind Kin der, ältere Menschen, Personen mit Grundkrankheiten und hospitalisierte Patienten generell. Eine Auswei tung auf den ambulanten Bereich und die gesamte Be völkerung zeichnet sich jedoch ab. Die Infektionen stellen aber nur einen Teil des Pro blems dar. Noch häufiger ist die Kolonisation asym ptomatischer Patienten mit mulitresistenten Erregern. Diese sind insofern von Bedeutung, als sie einerseits zu einer Erkrankung der betreffenden Person führen und andererseits auch unbemerkt auf andere Perso nen übertragen werden können.
Microbiology resource announcements, Jan 31, 2019
Here we report the whole-genome sequences of 15 clinical Streptococcus suis strains isolated from... more Here we report the whole-genome sequences of 15 clinical Streptococcus suis strains isolated from pigs in Switzerland. Although they originated from the same host and geographic origin, the strains showed a large amount of diversity. S treptococcus suis is a Gram-positive, facultative, anaerobic bacterium that is mainly found in the nasal mucosa and the tonsils of healthy pigs. Under predisposing circumstances, like inadequate sanitation or reduced immunity, S. suis can cause various diseases such as meningitis, septicemia, arthritis, pneumonia, and endocarditis (1). Besides being an important pig pathogen causing major economic losses, S. suis is considered a relevant zoonotic agent, especially in China and Southeast Asia (1-3). Currently, there are 29 described S. suis serotypes. Worldwide, serotype 2 is the most common reported serotype to cause infections in pigs, followed by serotypes 9 and 3 (1). In humans, the most frequently identified serotypes are serotype 2, followed by serotype 14 (1). We have sequenced 15 clinical S. suis strains (Table 1). The strains were originally isolated between 2006 and 2018 by streaking pig samples onto Columbia agar with sheep blood (Thermo Fisher Diagnostics AG, Pratteln, Switzerland). The plates were incubated at 37°C for 48 hours under aerobic conditions. Strains were identified by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) (Biotyper Compass Explorer software v.4.1.60, Bruker Daltonics, Bremen, Germany) and serotyped by multiplex PCR according to Kerdsin et al. (4). Genomic DNA was extracted using a DNA blood and tissue kit (Qiagen, Hombrechtikon, Switzerland) and prepared for sequencing with a Nextera DNA Flex sample preparation kit (Illumina, San Diego, CA, USA) on an Illumina MiniSeq sequencer with 150-bp paired-end reads. The sequencing resulted in an output of paired-end read sets containing 596,559 to 1,666,705 reads of 150 bp. The quality of the reads was checked using FastQC (https:// www.bioinformatics.babraham.ac.uk/projects/fastqc/). The reads passed all quality steps with the exception of the control step "per-base sequence content." Failure to pass this step, however, is typical for transposon-based libraries (FastQC manual [see https://www.bioinformatics.babraham.ac.uk/projects/fastqc/]) and was ignored. Reads were assembled de novo using Spades 3.12 (5) with activation of the "-careful" option. Raw assemblies were filtered for size larger than 1,000 bp and coverage of more than 25-fold. The final assemblies resulted in 13 genomes with a size between 1,878,848 and 2,135,450 bp and coverages between 50-and 120-fold (Table 1). The genomes consisted of 24 to 64 contigs per strain, and the largest contigs were 129 to 333 kbp. Strains SS1014 and PP464 had large genomes of 2,340,449 and 2,504,491 bp, with coverages of 50-and 39-fold, respectively. The SS1014 and PP464 genomes consisted of 204 and 94 contigs, the largest of which were 76 kb and 174 kb, respectively.
Pediatric Infectious Disease Journal, Apr 1, 2014
To evaluate the intrafamilial oropharyngeal transmission of Kingella kingae, we conducted a prosp... more To evaluate the intrafamilial oropharyngeal transmission of Kingella kingae, we conducted a prospective study among pairs of siblings. We found that 55% of children who suffered from osteoarticular infections due to K. kingae, and 40% of asymptomatic carriers of K. kingae had siblings with positive oropharyngeal carriage.
Fems Microbiology Reviews, Dec 12, 2016
This review discusses the role of generation of reactive oxygen species by the phagocyte NADPH ox... more This review discusses the role of generation of reactive oxygen species by the phagocyte NADPH oxidase NOX2 in host-pathogen interaction with a specific focus on S. aureus infections.
Photodiagnosis and Photodynamic Therapy, May 1, 2013
In dentistry, residual infection remains a major cause of failure after endodontic treatment; man... more In dentistry, residual infection remains a major cause of failure after endodontic treatment; many of these infections involve Enterococcus faecalis. In the current study, we explored the possibility that blue light activated photosensitizers could be used, in principle, to inactivate this microbe as an adjunct disinfection strategy for endodontic therapy. Three blue light absorbing photosensitizers, eosin-Y, rose bengal, and curcumin, were tested on E. faecalis grown in planktonic suspensions or biofilms. Photosensitizers were incubated for 30 min with bacteria then exposed to blue light (450-500 nm) for 240 s. Sodium hypochlorite (3%) was used as a control. After 48 h, the viability of E. faecalis was estimated by measuring colonyforming units post-exposure vs. untreated controls (CFU/mL). Blue light irradiation alone did not alter E. faecalis viability. For planktonic cultures, blue light activated eosin-Y (5 M), rose bengal (1 M), or curcumin (5 M) significantly (p < 0.05) reduced E. faecalis viability compared to exposure to the unirradiated photochemicals. For biofilm cultures, concentrations of lightactivated eosin-Y, rose bengal, and curcumin of 100, 10, and 10 M respectively, completely suppressed E. faecalis viability (p < 0.05). Although the current results are limited to an in vitro model, they support further exploration of blue light activated antimicrobials as an adjunct therapy in endodontic treatment.
Revue médicale suisse, 2014
Revue Médicale Suissewww.revmed.ch-12 novembre 2014 Revue Médicale Suissewww.revmed.ch-12 novembr... more Revue Médicale Suissewww.revmed.ch-12 novembre 2014 Revue Médicale Suissewww.revmed.ch-12 novembre 2014 2155 brought to you by CO metadata, citation and similar papers at core.ac.uk provided by Serveur académique lausa * à lire ** à lire absolument
Microbial genomics, May 12, 2023
The Swiss Pathogen Surveillance Platform (SPSP) is a shared secure surveillance platform between ... more The Swiss Pathogen Surveillance Platform (SPSP) is a shared secure surveillance platform between human and veterinary medicine, to also include environmental and foodborne isolates. It enables rapid and detailed transmission monitoring and outbreak surveillance of pathogens using whole genome sequencing data and associated metadata. It features controlled data access, complex dynamic queries, dedicated dashboards and automated data sharing with international repositories, providing actionable results for public health and the vision to improve societal well-being and health.
British Journal of Surgery, May 1, 2021
Objective Our objective was to describe the aetiologies of acute colitis and to identify patients... more Objective Our objective was to describe the aetiologies of acute colitis and to identify patients who require diagnostic endoscopy. Methods Patients with symptoms of gastrointestinal infection and colonic inflammation on computed tomography were prospectively included. Those immunosuppressed, with history of colorectal cancer or inflammatory bowel disease (IBD) were excluded. Stools were screened with BD-Max and BioFire FilmArray GI panel. Faecal calprotectin was determined. Patients with negative BD-Max underwent colonoscopy. The study was registered into clinicaltrials.gov (NCT02709213). Results One hundred and seventy-nine patients were included. BD-Max was positive in 93 patients (52%) and FilmArray in 108 patients (60.3%). Patients with infectious colitis (n = 103, 57.5%) were positive for Campylobacter spp (n = 57, 55.3%), Escherichia coli spp (n = 8, 7.8%), Clostridium difficile (n = 23, 22.3%), Salmonella spp (n = 9, 8.7%), viruses (n = 7, 6.8%), Shigella spp (n = 6, 5.8%), Entamoeba histolytica (n = 2, 1.9%) and others (n = 4, 3.9%). Eighty-six patients underwent colonoscopy, which was compatible with ischemic colitis in 18 patients (10.1%) and IBD in 4 patients (2.2%). Among patients with negative FilmArray, a faecal calprotectin >625μg/g allowed identifying patients with IBD with an area under ROC curve of 85.1%. Introduction of a diagnostic management algorithm including FilmArray and faecal calprotectin could allow decreasing unnecessary colonoscopies from 82 to 29 (corresponding to a decrease of 64.6%). Conclusion Computed tomography-proven colitis was mostly of infectious aetiology. Diagnostic management of patients with acute colitis should include broad molecular testing of the stools and, in patients with a calprotectin concentration >625μg/g, colonoscopy to exclude IBD.
British Journal of Surgery, May 1, 2021
Objective There is growing evidence supporting that the gut microbiota is a major driver of human... more Objective There is growing evidence supporting that the gut microbiota is a major driver of human health and disease. While gut microbiota transfer (GMT) is commonly used as an approach to restore "eubiosis", there is a surprising lack of data on whether the transferred microbiota efficiently and durably repopulate the gut of the transplanted subject. Moreover, little is known on the effects of GMT on non-alcoholic fatty liver disease (NAFLD). Methods Chronic dysbiosis and NAFLD-like liver injury were induced by feeding C57Bl/6j mice for 16 weeks with a high-fat diet. For GMT, dysbiotic mice underwent preliminary gut cleansing, followed by oral gavage with a suspension of fresh fecal matter procured from a pool of lean mice (1 dose, or 10 doses). We next characterized microbiota composition and we measured the relative abundance of specific pathobionts in recipient mice, using high-throughput shotgun analysis in a dynamic manner, over time. All experiments took place in a specific germ-free environment. Results After 4 months on a high-fat diet, mice displayed fatty liver infiltration with moderate parenchymal inflammatory changes. Dysbiosis was evidenced by a reduced bacterial diversity, as well as a dramatically increased abundance of Firmicutes, and lower Verrucomicrobia and Actinobacteria. Gut microbiota transfer was associated with a transitory reduction in NAFLD-induced hepatocellular injury. While dysbiotic mice displayed a shift in their microbiota composition towards that of lean donors after GMT, this effect rapidly faded after one week, and mice recovered their initial, dysbiotic microbiota. Conclusion The current study indicates that, when used in mice with chronically established dysbiosis, GMT is merely associated with transitory changes in gut microbiota composition, as well as significant but moderate reduction in hepatocellular injury.
Swiss medical forum =, Nov 14, 2018
Forum médical suisse =, Nov 14, 2018
Une détermination rapide et fiable des résistances aux antibiotiques est indispensable pour la mi... more Une détermination rapide et fiable des résistances aux antibiotiques est indispensable pour la mise en place d'un traitement efficace et ciblé. La surveillance de la situation des résistances livre des informations essentielles pour la détermination du traitement empirique et aide à prendre des mesures destinées à éviter une plus large propagation des bactéries résistantes aux antibiotiques.