Reinhard Zbinden | Zurich University of Applied Sciences (original) (raw)

Papers by Reinhard Zbinden

BMC Infectious Diseases, Dec 1, 2013

Background: Neisseria gonorrhoeae can rapidly develop resistance to antimicrobial agents. Over th... more Background: Neisseria gonorrhoeae can rapidly develop resistance to antimicrobial agents. Over the last years, decreased gonococcal susceptibility to third-generation cephalosporins, especially cefixime, emerged worldwide. Therefore, current international guidelines recommend dual therapy for gonorrhoea with ceftriaxone plus either azithromycin or doxycycline. Gonococcal susceptibility data in Switzerland are sparse. Methods: We investigated the prevalence of antibiotic susceptibility of N. gonorrhoeae in specimens collected between 1990 and 2012 at the University of Zurich, Switzerland. Minimum inhibitory concentrations (MICs) for cefixime, ceftriaxone, ciprofloxacin, and penicillin were determined by Etests. The European Committee on Antimicrobial Susceptibility Testing (EUCAST) breakpoints were used to define reduced susceptibility. Results: A total of 320 isolates were tested. Between 1990 and 2006 all tested samples were susceptible to both cephalosporins. Subsequently, the prevalence of elevated MICs for cefixime increased to 10.4% (2007/2008), 11.5%

Clinical Infectious Diseases, Mar 15, 2002

We investigated an outbreak of Serratia marcescens in the neonatal intensive care unit (NICU) of ... more We investigated an outbreak of Serratia marcescens in the neonatal intensive care unit (NICU) of the University Hospital of Zurich. S. marcescens infection was detected in 4 children transferred from the NICU to the University Children's Hospital (Zurich). All isolates showed identical banding patterns by pulsed-field gel electrophoresis (PFGE). In a prevalence survey, 11 of 20 neonates were found to be colonized. S. marcescens was isolated from bottles of liquid theophylline. Despite replacement of these bottles, S. marcescens colonization was detected in additional patients. Prospective collection of stool and gastric aspirate specimens revealed that colonization occurred in some babies within 24 hours after delivery. These isolates showed a different genotype. Cultures of milk from used milk bottles yielded S. marcescens. These isolates showed a third genotype. The method of reprocessing bottles was changed to thermal disinfection. In follow-up prevalence studies, 0 of 29 neonates were found to be colonized by S. marcescens. In summary, 3 consecutive outbreaks caused by 3 genetically unrelated clones of S. marcescens could be documented. Contaminated milk could be identified as the source of at least the third outbreak.

necrotizing fasciitis due to Streptococcus pneumoniae after renal transplantation

Eye and Vision, 2022

Background Infectious keratitis is a major cause of global blindness. We tested whether standalon... more Background Infectious keratitis is a major cause of global blindness. We tested whether standalone photoactivated chromophore corneal cross-linking (PACK-CXL) may be an effective first-line treatment in early to moderate infectious keratitis, compared with standard antimicrobial treatment. Methods This is a randomized, controlled, multinational phase 3 clinical trial. Participants in five centers in Egypt, India, Iran, Israel, and China, aged ≥ 18 years, with infectious keratitis of presumed bacterial, fungal, or mixed origin, were randomly assigned (1:1) to PACK-CXL, or antimicrobial therapy. Outcomes measures included healing, defined as time to re-epithelialization of the corneal epithelial defect in the absence of inflammatory activity in the anterior chamber and clearance of stromal infiltrates. Treatment success was defined as the complete resolution of signs of infection. Results Between July 21, 2016, and March 4, 2020, participants were randomly assigned to receive PACK-CXL...

Photodiagnosis and Photodynamic Therapy, 2020

Background: Current standard skin antisepsis to prevent surgical site infections are ineffective ... more Background: Current standard skin antisepsis to prevent surgical site infections are ineffective to eradicate all skin-colonizing bacteria. Photodynamic therapy (PDT) has shown bactericidal effects in vitro, but no clinical study with improvements in skin antisepsis has been documented. Methods: We investigated the effect of methyl aminolevulinate (MAL)-PDT versus no PDT for skin antisepsis treatment (povidone-iodine/alcohol) in the groin of 10 healthy participants. Skin swabs were taken at baseline, immediately after PDT, and after skin antisepsis treatment to cultivate bacteria. At day 7 and 21, bacterial cultures were repeated before and after antisepsis treatment without PDT. Skin biopsies were performed to examine the grade of inflammation. Results: Skin-colonizing bacteria were found in all 20 participants at baseline sampling. Immediately after MAL-PDT, skin was sterile in 7 (70%) participants before and in all 10 (100%) participants after skin antisepsis treatment. In contrast, we found skin-colonizing bacteria in 5 (50%) participants of the control group receiving only skin antisepsis. After 7 and 21 days, skin sterility was similar to the baseline. We observed slight perivascular inflammation with lymphocytes and eosinophils without changes in the histomorphology of eccrine or sebaceous glands in skin biopsies. PDT was generally well tolerated except for localized redness. Conclusion: MAL-PDT with skin antisepsis treatment sterilized skin immediately after its use but did not maintain sterility 7-21 days post-treatment. Due to local side effects, further clinical studies with less intensive PDT conditions or other photosensitizers are needed before PDT is integrated into clinical practice.

BMC Infectious Diseases, 2021

Background Aeromonas hydrophila is a gram-negative facultative anaerobic coccobacillus, which is ... more Background Aeromonas hydrophila is a gram-negative facultative anaerobic coccobacillus, which is an environmental opportunistic pathogen. A. hydrophila are involved in several infectious diseases such as gastroenteritis, septicemia and wound infections. However, gastroenteritis caused by Aeromonas spp. are rare and the clinical relevance of Aeromonas species in stool specimens is still under debate. Case presentation Our case concerns a 32-year-old woman who presented at hospital with a worsening watery diarrhea and fever requiring intensive care. A cholera-like illness was diagnosed. The patient had a past history of an anti-Hu syndrome with a myenteric ganglionitis. A molecular multiplex RT-PCR (QIAstat-Dx Gastrointestinal Panel, QIAGEN) covering a broad spectrum of diverse gastrointestinal pathogens performed directly from the stool was negative but the stool culture revealed growth of A. hydrophila. Further investigations of the A. hydrophila strain in cell cultures revealed the...

Clinical Infectious Diseases, 2020

Background Aspergillus spp. of section Usti (A. ustus) represent a rare cause of invasive aspergi... more Background Aspergillus spp. of section Usti (A. ustus) represent a rare cause of invasive aspergillosis (IA). This multicenter study describes the epidemiology and outcome of A. ustus infections. Methods Patients with A. ustus isolated from any clinical specimen were retrospectively identified in 22 hospitals from 8 countries. When available, isolates were sent for species identification (BenA/CaM sequencing) and antifungal susceptibility testing. Additional cases were identified by review of the literature. Cases were classified as proven/probable IA or no infection, according to standard international criteria. Results Clinical report forms were obtained for 90 patients, of whom 27 had proven/probable IA. An additional 45 cases were identified from literature review for a total of 72 cases of proven/probable IA. Hematopoietic cell and solid-organ transplant recipients accounted for 47% and 33% cases, respectively. Only 8% patients were neutropenic at time of diagnosis. Ongoing ant...

Journal of Clinical Microbiology, 1991

In a prospective survey, all transplant patients at the hospital of the University of Zurich were... more In a prospective survey, all transplant patients at the hospital of the University of Zurich were screened for cytomegalovirus (CMV) infection. CMV infections were detected in a total of 40 of 104 transplant recipients; 31 could be diagnosed by CMV immunoglobulin M serology, 27 could be diagnosed by viremia, 11 could be diagnosed by antigenemia, and 13 could be diagnosed by the start of virus secretion. Combined application of serology and the detection of viremia showed the highest sensitivity (39 of 40 cases). Of the patients with severe clinical symptoms, six of seven had primary CMV infections caused by a positive transplant. Therefore, it is strongly indicated that patients with known risk factors should be regularly surveyed by a combination of methods.

Clinical Infectious Diseases, 2018

Background. An increase in the incidence of hip periprosthetic joint infections caused by Cutibac... more Background. An increase in the incidence of hip periprosthetic joint infections caused by Cutibacterium avidum has recently been detected after hip arthroplasty with an anterior surgical approach. We raised the question of whether skin colonization with C. avidum differs between the anterior and the lateral thigh as areas of surgical incision fields. Methods. Between February and June 2017, we analyzed skin scrapings from the groin and the anterior and lateral thigh in patients undergoing a primary hip arthroplasty. We anaerobically cultured plated swab samples for Cutibacterium spp. for ≥7 days. Univariate logistic regression analysis was used to explore associations between body mass index (BMI) and colonization rate at different sites. Results. Twenty-one of 65 patients (32.3%) were colonized with C. avidum at any site, mainly at the groin (n = 16; 24.6%), which was significantly higher at the anterior (n = 5; 7.7%; P = .009) or lateral (n = 6; 9.2%; P = .02) thigh. Patients colonized with C. avidum did not differ from noncolonized patients in age or sex, but their BMIs were significantly higher (30.1 vs 25.6 kg/m 2 , respectively; P = .02). Furthermore, increased BMI was associated with colonization at the groin (odds ratio per unit BMI increase, 1.15; 95% confidence interval; 1.03-1.29; P = .01). Conclusions. The groin, rather than the anterior thigh, showed colonization for C. avidum in obese patients. Further studies are needed to evaluate current skin disinfection and draping protocols for hip arthroplasty, particularly in obese patients.

Journal of Clinical Medicine, 2019

Helicobacter pylori is a major human pathogen that causes a wide range of gastrointestinal pathol... more Helicobacter pylori is a major human pathogen that causes a wide range of gastrointestinal pathology. Progression of H. pylori induced gastritis to more severe disease has been found to highly correlate with the array of virulence factors expressed by the pathogen. The objective of this study was twofold: first, to characterize the genetic diversity of H. pylori strains isolated from 41 non-atrophic gastritis patients in Switzerland, an issue that has not been investigated to date. And second, to assess the prevalence and sequence variation of H. pylori virulence factors (cagA, vacA, iceA and dupA) and genes encoding outer membrane proteins (OMPs; babA, babB, sabA, sabB, hopZ, hopQ and oipA) by whole genome sequencing (WGS) using an Illumina MiSeq platform. WGS identified high genetic diversity in the analyzed H. pylori strains. Most H. pylori isolates were assigned to hpEurope (95.0%, 39/41), and the remaining ones (5.0%, 2/41) to hpEastAsia, subpopulation hspEAsia. Analysis of vir...

Journal of Clinical Medicine, 2019

Helicobacter pylori is a major human pathogen. Diagnosis of H. pylori infection and determination... more Helicobacter pylori is a major human pathogen. Diagnosis of H. pylori infection and determination of its antibiotic susceptibility still mainly rely on culture and phenotypic drug susceptibility testing (DST) that is time-consuming and laborious. Whole genome sequencing (WGS) has recently emerged in medical microbiology as a diagnostic tool for reliable drug resistance prediction in bacterial pathogens. The aim of this study was to compare phenotypic DST results with the predictions based on the presence of genetic determinants identified in the H. pylori genome using WGS. Phenotypic resistance to clarithromycin, metronidazole, tetracycline, levofloxacin, and rifampicin was determined in 140 clinical H. pylori isolates by E-Test®, and the occurrence of certain single nucleotide polymorphisms (SNPs) in target genes was determined by WGS. Overall, there was a high congruence of >99% between phenotypic DST results for clarithromycin, levofloxacin, and rifampicin and SNPs identified ...

PLOS ONE, 2018

Irrigation water is a major source of fresh produce contamination with undesired microorganisms i... more Irrigation water is a major source of fresh produce contamination with undesired microorganisms including antibiotic-resistant bacteria (ARB), and contaminated fresh produce can transfer ARB to the consumer especially when consumed raw. Nevertheless, no legal guidelines exist so far regulating quality of irrigation water with respect to ARB. We therefore examined irrigation water from major vegetable growing areas for occurrence of antibioticresistant indicator bacteria Escherichia coli and Enterococcus spp., including extendedspectrum β-lactamase (ESBL)-producing E. coli and vancomycin-resistant Enterococcus spp. Occurrence of ARB strains was compared to total numbers of the respective species. We categorized water samples according to total numbers and found that categories with higher total E. coli or Enterococcus spp. numbers generally had an increased proportion of respective ARB-positive samples. We further detected high prevalence of ESBL-producing E. coli with eight positive samples of thirty-six (22%), while two presumptive vancomycinresistant Enterococcus spp. were vancomycin-susceptible in confirmatory tests. In disk diffusion assays all ESBL-producing E. coli were multidrug-resistant (n = 21) and wholegenome sequencing of selected strains revealed a multitude of transmissible resistance genes (ARG), with bla CTX-M-1 (4 of 11) and bla CTX-M-15 (3 of 11) as the most frequent ESBL genes. Overall, the increased occurrence of indicator ARB with increased total indicator bacteria suggests that the latter might be a suitable estimate for presence of respective ARB strains. Finally, the high prevalence of ESBL-producing E. coli with transmissible ARG emphasizes the need to establish legal critical values and monitoring guidelines for ARB in irrigation water.

Journal of Clinical Microbiology, 2018

ABSTRACTAggregatibacterspecies are commensal bacteria of human mucosal surfaces that are sometime... more ABSTRACTAggregatibacterspecies are commensal bacteria of human mucosal surfaces that are sometimes involved in serious invasive infections. During the investigation of strains cultured from various clinical specimens, we encountered a coherent group of 10 isolates that could not be allocated to any validly named species by phenotype, mass spectrometry, or partial 16S rRNA gene sequencing. Whole-genome sequencing revealed a phylogenetic cluster related to but separate fromAggregatibacter aphrophilus. The meanin silicoDNA hybridization value for strains of the new cluster versusA. aphrophiluswas 56% (range, 53.7 to 58.0%), whereas the average nucleotide identity was 94.4% (range, 93.9 to 94.8%). The new cluster exhibited aggregative properties typical of the genusAggregatibacter. Key phenotypic tests for discrimination of the new cluster from validly namedAggregatibacterspecies are alanine-phenylalanine-proline arylamidase,N-acetylglucosamine, and β-galactosidase. The nameAggregatibac...

The Journal of infection, 2018

Breakthrough candidemia (BTC) on fluconazole was associated with non-susceptible Candida spp. and... more Breakthrough candidemia (BTC) on fluconazole was associated with non-susceptible Candida spp. and increased mortality. This nationwide FUNGINOS study analyzed clinical and mycological BTC characteristics. A 3-year prospective study was conducted in 567 consecutive candidemias. Species identification and antifungal susceptibility testing (CLSI) were performed in the FUNGINOS reference laboratory. Data were analyzed according to STROBE criteria. 43/576 (8%) BTC occurred: 37/43 (86%) on fluconazole (28 prophylaxis, median 200 mg/day). 21% BTC vs. 23% non-BTC presented severe sepsis/septic shock. Overall mortality was 34% vs. 32%. BTC was associated with gastrointestinal mucositis (multivariate OR 5.25, 95%CI 2.23-12.40, p < 0.001) and graft-versus-host-disease (6.25, 1.00-38.87, p = 0.05), immunosuppression (2.42, 1.03-5.68, p = 0.043), and parenteral nutrition (2.87, 1.44-5.71, p = 0.003). Non-albicans Candida were isolated in 58% BTC vs. 35% non-BTC (p = 0.005). 63% of 16 BTC occu...

Diagnostic Microbiology and Infectious Disease, 2017

The following work is licensed under a Creative Commons: Attribution-NonCommercial-NoDerivatives ... more The following work is licensed under a Creative Commons: Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) License.

Intensive care medicine, Jun 7, 2017

Journal of Clinical Microbiology, 2016

Diagnosis of Propionibacterium acnes bone and joint infection is challenging due to the long cult... more Diagnosis of Propionibacterium acnes bone and joint infection is challenging due to the long cultivation time of up to 14 days. We retrospectively studied whether reducing the cultivation time to 7 days allows accurate diagnosis without losing sensitivity. We identified patients with at least one positive P. acnes sample between 2005 and 2015 and grouped them into “infection” and “no infection.” An infection was defined when at least two samples from the same case were positive. Clinical and microbiological data, including time to positivity for different cultivation methods, were recorded. We found 70 cases of proven P. acnes infection with a significant faster median time to positivity of 6 days (range, 2 to 11 days) compared to 9 days in 47 cases with P. acnes identified as a contamination ( P < 0.0001). In 15 of 70 (21.4%) patients with an infection, tissue samples were positive after day 7 and in 6 patients (8.6%) after day 10 when a blind subculture of the thioglycolate bro...

Clinical Microbiology and Infection, 1996

Objective: The susceptibilities t o penicillin, tetracycline, erythromycin, gentamicin, vancomyci... more Objective: The susceptibilities t o penicillin, tetracycline, erythromycin, gentamicin, vancomycin and teicoplanin of 58 strains of Corynebacterium jeikeium were assessed by disk diffusion and agar dilution reference methods. Methods: Zone sizes and minimal inhibitory concentrations (MIC) by agar dilution were interpreted using the ranges in the NCCLS tables for organisms other than Haemophilus, Neisseria gonorrhoeae, and Streptococcus pneumoniae. Results: By agar dilution, 14%, 88%, 17% and 26% of the 58 isolates were susceptible t o penicillin, tetracycline, erythromycin, and gentamicin, respectively. Using the breakpoints for Listeria monocytogenes, all strains showed concordant results for penicillin by disk diffusion. Discrepancies in the interpretative categories by disk diffusion were found in four cases (two very major and two minor) for tetracycline, in nine (two very major, two major, and five minor) for erythromycin, and in 1 case (very major) for gentamicin. All 58 strains were susceptible t o vancornycin and teicoplanin by agar dilution and disk diffusion. The overall agreement of interpretative disk diffusion for all six antibiotics was 95.9%. In addition, all strains were susceptible to both glycopeptides by E-test. However, for vancomycin the MIC results in 58.6% were two log2 dilutions and in 1.7% more than two log2 dilutions higher by E-test than by agar dilution, whereas for teicoplanin agreement within one log2 dilution was 100%. Conclusions: Further evaluation of methodologies of disk diffusion is required t o obtain a better agreement for erythromycin and tetracycline. The criteria of the NCCLS for interpretation of disk diffusion are adequate for susceptibility testing of C. jeikeium to penicillin, gentamicin, vancomycin and teicoplanin.

Neonatology, 2014

Background: The use of probiotics as prophylaxis for necrotizing enterocolitis (NEC) in preterm i... more Background: The use of probiotics as prophylaxis for necrotizing enterocolitis (NEC) in preterm infants is being increasingly practised. Objective: We report, for the first time, a case series of 3 preterm, very-low-birth-weight (VLBW) infants who developed bacteremia with Bifidobacterium longum on probiotic therapy with Infloran® containing viable B. longum. Methods: We retrospectively reviewed data of 3 infants (of gestational age <30 weeks and birth weight <1,230 g). They were admitted to the neonatal intensive care unit. Clinical data were retrieved from their medical records. Results: In infants 1 and 2, B. longum was isolated from the blood cultures when they were on probiotic therapy with Infloran or shortly after, respectively, and was interpreted as transient bacteremia. The clinical presentation of these infants did not require antibiotic treatment after the isolation of B. longum. Infant 3 developed an NEC despite probiotic therapy with Infloran and the blood cultur...

Head & neck, Jan 18, 2014

The goal of this study was to evaluate prospectively the presence and impact of the gastric carci... more The goal of this study was to evaluate prospectively the presence and impact of the gastric carcinogen Helicobacter pylori in the upper aerodigestive tract. Previous studies suggested it could represent a risk factor for head and neck squamous cell carcinoma. Serology, rapid urease test, and quantitative polymerase chain reaction (qPCR) for H. pylori were performed in head and neck cancer patients (N=56) and cancer-free controls (N=90). Comparison between groups was done using logistic regression analysis. Rates of positive serology and rapid urease test did not differ between the two groups in logistic regression analysis (P=0.677 and P=0.633, respectively). Birth in a developing country and age above 50 years old were predictors of positive serology (P<0.001 and P=0.040, respectively). Using qPCR, no biopsy showed presence of H.pylori. This study challenges the concept that H. pylori may be a risk factor for head and neck squamous cell carcinoma. This article is protected by co...

BMC Infectious Diseases, Dec 1, 2013

Background: Neisseria gonorrhoeae can rapidly develop resistance to antimicrobial agents. Over th... more Background: Neisseria gonorrhoeae can rapidly develop resistance to antimicrobial agents. Over the last years, decreased gonococcal susceptibility to third-generation cephalosporins, especially cefixime, emerged worldwide. Therefore, current international guidelines recommend dual therapy for gonorrhoea with ceftriaxone plus either azithromycin or doxycycline. Gonococcal susceptibility data in Switzerland are sparse. Methods: We investigated the prevalence of antibiotic susceptibility of N. gonorrhoeae in specimens collected between 1990 and 2012 at the University of Zurich, Switzerland. Minimum inhibitory concentrations (MICs) for cefixime, ceftriaxone, ciprofloxacin, and penicillin were determined by Etests. The European Committee on Antimicrobial Susceptibility Testing (EUCAST) breakpoints were used to define reduced susceptibility. Results: A total of 320 isolates were tested. Between 1990 and 2006 all tested samples were susceptible to both cephalosporins. Subsequently, the prevalence of elevated MICs for cefixime increased to 10.4% (2007/2008), 11.5%

Clinical Infectious Diseases, Mar 15, 2002

We investigated an outbreak of Serratia marcescens in the neonatal intensive care unit (NICU) of ... more We investigated an outbreak of Serratia marcescens in the neonatal intensive care unit (NICU) of the University Hospital of Zurich. S. marcescens infection was detected in 4 children transferred from the NICU to the University Children's Hospital (Zurich). All isolates showed identical banding patterns by pulsed-field gel electrophoresis (PFGE). In a prevalence survey, 11 of 20 neonates were found to be colonized. S. marcescens was isolated from bottles of liquid theophylline. Despite replacement of these bottles, S. marcescens colonization was detected in additional patients. Prospective collection of stool and gastric aspirate specimens revealed that colonization occurred in some babies within 24 hours after delivery. These isolates showed a different genotype. Cultures of milk from used milk bottles yielded S. marcescens. These isolates showed a third genotype. The method of reprocessing bottles was changed to thermal disinfection. In follow-up prevalence studies, 0 of 29 neonates were found to be colonized by S. marcescens. In summary, 3 consecutive outbreaks caused by 3 genetically unrelated clones of S. marcescens could be documented. Contaminated milk could be identified as the source of at least the third outbreak.

necrotizing fasciitis due to Streptococcus pneumoniae after renal transplantation

Eye and Vision, 2022

Background Infectious keratitis is a major cause of global blindness. We tested whether standalon... more Background Infectious keratitis is a major cause of global blindness. We tested whether standalone photoactivated chromophore corneal cross-linking (PACK-CXL) may be an effective first-line treatment in early to moderate infectious keratitis, compared with standard antimicrobial treatment. Methods This is a randomized, controlled, multinational phase 3 clinical trial. Participants in five centers in Egypt, India, Iran, Israel, and China, aged ≥ 18 years, with infectious keratitis of presumed bacterial, fungal, or mixed origin, were randomly assigned (1:1) to PACK-CXL, or antimicrobial therapy. Outcomes measures included healing, defined as time to re-epithelialization of the corneal epithelial defect in the absence of inflammatory activity in the anterior chamber and clearance of stromal infiltrates. Treatment success was defined as the complete resolution of signs of infection. Results Between July 21, 2016, and March 4, 2020, participants were randomly assigned to receive PACK-CXL...

Photodiagnosis and Photodynamic Therapy, 2020

Background: Current standard skin antisepsis to prevent surgical site infections are ineffective ... more Background: Current standard skin antisepsis to prevent surgical site infections are ineffective to eradicate all skin-colonizing bacteria. Photodynamic therapy (PDT) has shown bactericidal effects in vitro, but no clinical study with improvements in skin antisepsis has been documented. Methods: We investigated the effect of methyl aminolevulinate (MAL)-PDT versus no PDT for skin antisepsis treatment (povidone-iodine/alcohol) in the groin of 10 healthy participants. Skin swabs were taken at baseline, immediately after PDT, and after skin antisepsis treatment to cultivate bacteria. At day 7 and 21, bacterial cultures were repeated before and after antisepsis treatment without PDT. Skin biopsies were performed to examine the grade of inflammation. Results: Skin-colonizing bacteria were found in all 20 participants at baseline sampling. Immediately after MAL-PDT, skin was sterile in 7 (70%) participants before and in all 10 (100%) participants after skin antisepsis treatment. In contrast, we found skin-colonizing bacteria in 5 (50%) participants of the control group receiving only skin antisepsis. After 7 and 21 days, skin sterility was similar to the baseline. We observed slight perivascular inflammation with lymphocytes and eosinophils without changes in the histomorphology of eccrine or sebaceous glands in skin biopsies. PDT was generally well tolerated except for localized redness. Conclusion: MAL-PDT with skin antisepsis treatment sterilized skin immediately after its use but did not maintain sterility 7-21 days post-treatment. Due to local side effects, further clinical studies with less intensive PDT conditions or other photosensitizers are needed before PDT is integrated into clinical practice.

BMC Infectious Diseases, 2021

Background Aeromonas hydrophila is a gram-negative facultative anaerobic coccobacillus, which is ... more Background Aeromonas hydrophila is a gram-negative facultative anaerobic coccobacillus, which is an environmental opportunistic pathogen. A. hydrophila are involved in several infectious diseases such as gastroenteritis, septicemia and wound infections. However, gastroenteritis caused by Aeromonas spp. are rare and the clinical relevance of Aeromonas species in stool specimens is still under debate. Case presentation Our case concerns a 32-year-old woman who presented at hospital with a worsening watery diarrhea and fever requiring intensive care. A cholera-like illness was diagnosed. The patient had a past history of an anti-Hu syndrome with a myenteric ganglionitis. A molecular multiplex RT-PCR (QIAstat-Dx Gastrointestinal Panel, QIAGEN) covering a broad spectrum of diverse gastrointestinal pathogens performed directly from the stool was negative but the stool culture revealed growth of A. hydrophila. Further investigations of the A. hydrophila strain in cell cultures revealed the...

Clinical Infectious Diseases, 2020

Background Aspergillus spp. of section Usti (A. ustus) represent a rare cause of invasive aspergi... more Background Aspergillus spp. of section Usti (A. ustus) represent a rare cause of invasive aspergillosis (IA). This multicenter study describes the epidemiology and outcome of A. ustus infections. Methods Patients with A. ustus isolated from any clinical specimen were retrospectively identified in 22 hospitals from 8 countries. When available, isolates were sent for species identification (BenA/CaM sequencing) and antifungal susceptibility testing. Additional cases were identified by review of the literature. Cases were classified as proven/probable IA or no infection, according to standard international criteria. Results Clinical report forms were obtained for 90 patients, of whom 27 had proven/probable IA. An additional 45 cases were identified from literature review for a total of 72 cases of proven/probable IA. Hematopoietic cell and solid-organ transplant recipients accounted for 47% and 33% cases, respectively. Only 8% patients were neutropenic at time of diagnosis. Ongoing ant...

Journal of Clinical Microbiology, 1991

In a prospective survey, all transplant patients at the hospital of the University of Zurich were... more In a prospective survey, all transplant patients at the hospital of the University of Zurich were screened for cytomegalovirus (CMV) infection. CMV infections were detected in a total of 40 of 104 transplant recipients; 31 could be diagnosed by CMV immunoglobulin M serology, 27 could be diagnosed by viremia, 11 could be diagnosed by antigenemia, and 13 could be diagnosed by the start of virus secretion. Combined application of serology and the detection of viremia showed the highest sensitivity (39 of 40 cases). Of the patients with severe clinical symptoms, six of seven had primary CMV infections caused by a positive transplant. Therefore, it is strongly indicated that patients with known risk factors should be regularly surveyed by a combination of methods.

Clinical Infectious Diseases, 2018

Background. An increase in the incidence of hip periprosthetic joint infections caused by Cutibac... more Background. An increase in the incidence of hip periprosthetic joint infections caused by Cutibacterium avidum has recently been detected after hip arthroplasty with an anterior surgical approach. We raised the question of whether skin colonization with C. avidum differs between the anterior and the lateral thigh as areas of surgical incision fields. Methods. Between February and June 2017, we analyzed skin scrapings from the groin and the anterior and lateral thigh in patients undergoing a primary hip arthroplasty. We anaerobically cultured plated swab samples for Cutibacterium spp. for ≥7 days. Univariate logistic regression analysis was used to explore associations between body mass index (BMI) and colonization rate at different sites. Results. Twenty-one of 65 patients (32.3%) were colonized with C. avidum at any site, mainly at the groin (n = 16; 24.6%), which was significantly higher at the anterior (n = 5; 7.7%; P = .009) or lateral (n = 6; 9.2%; P = .02) thigh. Patients colonized with C. avidum did not differ from noncolonized patients in age or sex, but their BMIs were significantly higher (30.1 vs 25.6 kg/m 2 , respectively; P = .02). Furthermore, increased BMI was associated with colonization at the groin (odds ratio per unit BMI increase, 1.15; 95% confidence interval; 1.03-1.29; P = .01). Conclusions. The groin, rather than the anterior thigh, showed colonization for C. avidum in obese patients. Further studies are needed to evaluate current skin disinfection and draping protocols for hip arthroplasty, particularly in obese patients.

Journal of Clinical Medicine, 2019

Helicobacter pylori is a major human pathogen that causes a wide range of gastrointestinal pathol... more Helicobacter pylori is a major human pathogen that causes a wide range of gastrointestinal pathology. Progression of H. pylori induced gastritis to more severe disease has been found to highly correlate with the array of virulence factors expressed by the pathogen. The objective of this study was twofold: first, to characterize the genetic diversity of H. pylori strains isolated from 41 non-atrophic gastritis patients in Switzerland, an issue that has not been investigated to date. And second, to assess the prevalence and sequence variation of H. pylori virulence factors (cagA, vacA, iceA and dupA) and genes encoding outer membrane proteins (OMPs; babA, babB, sabA, sabB, hopZ, hopQ and oipA) by whole genome sequencing (WGS) using an Illumina MiSeq platform. WGS identified high genetic diversity in the analyzed H. pylori strains. Most H. pylori isolates were assigned to hpEurope (95.0%, 39/41), and the remaining ones (5.0%, 2/41) to hpEastAsia, subpopulation hspEAsia. Analysis of vir...

Journal of Clinical Medicine, 2019

Helicobacter pylori is a major human pathogen. Diagnosis of H. pylori infection and determination... more Helicobacter pylori is a major human pathogen. Diagnosis of H. pylori infection and determination of its antibiotic susceptibility still mainly rely on culture and phenotypic drug susceptibility testing (DST) that is time-consuming and laborious. Whole genome sequencing (WGS) has recently emerged in medical microbiology as a diagnostic tool for reliable drug resistance prediction in bacterial pathogens. The aim of this study was to compare phenotypic DST results with the predictions based on the presence of genetic determinants identified in the H. pylori genome using WGS. Phenotypic resistance to clarithromycin, metronidazole, tetracycline, levofloxacin, and rifampicin was determined in 140 clinical H. pylori isolates by E-Test®, and the occurrence of certain single nucleotide polymorphisms (SNPs) in target genes was determined by WGS. Overall, there was a high congruence of >99% between phenotypic DST results for clarithromycin, levofloxacin, and rifampicin and SNPs identified ...

PLOS ONE, 2018

Irrigation water is a major source of fresh produce contamination with undesired microorganisms i... more Irrigation water is a major source of fresh produce contamination with undesired microorganisms including antibiotic-resistant bacteria (ARB), and contaminated fresh produce can transfer ARB to the consumer especially when consumed raw. Nevertheless, no legal guidelines exist so far regulating quality of irrigation water with respect to ARB. We therefore examined irrigation water from major vegetable growing areas for occurrence of antibioticresistant indicator bacteria Escherichia coli and Enterococcus spp., including extendedspectrum β-lactamase (ESBL)-producing E. coli and vancomycin-resistant Enterococcus spp. Occurrence of ARB strains was compared to total numbers of the respective species. We categorized water samples according to total numbers and found that categories with higher total E. coli or Enterococcus spp. numbers generally had an increased proportion of respective ARB-positive samples. We further detected high prevalence of ESBL-producing E. coli with eight positive samples of thirty-six (22%), while two presumptive vancomycinresistant Enterococcus spp. were vancomycin-susceptible in confirmatory tests. In disk diffusion assays all ESBL-producing E. coli were multidrug-resistant (n = 21) and wholegenome sequencing of selected strains revealed a multitude of transmissible resistance genes (ARG), with bla CTX-M-1 (4 of 11) and bla CTX-M-15 (3 of 11) as the most frequent ESBL genes. Overall, the increased occurrence of indicator ARB with increased total indicator bacteria suggests that the latter might be a suitable estimate for presence of respective ARB strains. Finally, the high prevalence of ESBL-producing E. coli with transmissible ARG emphasizes the need to establish legal critical values and monitoring guidelines for ARB in irrigation water.

Journal of Clinical Microbiology, 2018

ABSTRACTAggregatibacterspecies are commensal bacteria of human mucosal surfaces that are sometime... more ABSTRACTAggregatibacterspecies are commensal bacteria of human mucosal surfaces that are sometimes involved in serious invasive infections. During the investigation of strains cultured from various clinical specimens, we encountered a coherent group of 10 isolates that could not be allocated to any validly named species by phenotype, mass spectrometry, or partial 16S rRNA gene sequencing. Whole-genome sequencing revealed a phylogenetic cluster related to but separate fromAggregatibacter aphrophilus. The meanin silicoDNA hybridization value for strains of the new cluster versusA. aphrophiluswas 56% (range, 53.7 to 58.0%), whereas the average nucleotide identity was 94.4% (range, 93.9 to 94.8%). The new cluster exhibited aggregative properties typical of the genusAggregatibacter. Key phenotypic tests for discrimination of the new cluster from validly namedAggregatibacterspecies are alanine-phenylalanine-proline arylamidase,N-acetylglucosamine, and β-galactosidase. The nameAggregatibac...

The Journal of infection, 2018

Breakthrough candidemia (BTC) on fluconazole was associated with non-susceptible Candida spp. and... more Breakthrough candidemia (BTC) on fluconazole was associated with non-susceptible Candida spp. and increased mortality. This nationwide FUNGINOS study analyzed clinical and mycological BTC characteristics. A 3-year prospective study was conducted in 567 consecutive candidemias. Species identification and antifungal susceptibility testing (CLSI) were performed in the FUNGINOS reference laboratory. Data were analyzed according to STROBE criteria. 43/576 (8%) BTC occurred: 37/43 (86%) on fluconazole (28 prophylaxis, median 200 mg/day). 21% BTC vs. 23% non-BTC presented severe sepsis/septic shock. Overall mortality was 34% vs. 32%. BTC was associated with gastrointestinal mucositis (multivariate OR 5.25, 95%CI 2.23-12.40, p < 0.001) and graft-versus-host-disease (6.25, 1.00-38.87, p = 0.05), immunosuppression (2.42, 1.03-5.68, p = 0.043), and parenteral nutrition (2.87, 1.44-5.71, p = 0.003). Non-albicans Candida were isolated in 58% BTC vs. 35% non-BTC (p = 0.005). 63% of 16 BTC occu...

Diagnostic Microbiology and Infectious Disease, 2017

The following work is licensed under a Creative Commons: Attribution-NonCommercial-NoDerivatives ... more The following work is licensed under a Creative Commons: Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) License.

Intensive care medicine, Jun 7, 2017

Journal of Clinical Microbiology, 2016

Diagnosis of Propionibacterium acnes bone and joint infection is challenging due to the long cult... more Diagnosis of Propionibacterium acnes bone and joint infection is challenging due to the long cultivation time of up to 14 days. We retrospectively studied whether reducing the cultivation time to 7 days allows accurate diagnosis without losing sensitivity. We identified patients with at least one positive P. acnes sample between 2005 and 2015 and grouped them into “infection” and “no infection.” An infection was defined when at least two samples from the same case were positive. Clinical and microbiological data, including time to positivity for different cultivation methods, were recorded. We found 70 cases of proven P. acnes infection with a significant faster median time to positivity of 6 days (range, 2 to 11 days) compared to 9 days in 47 cases with P. acnes identified as a contamination ( P < 0.0001). In 15 of 70 (21.4%) patients with an infection, tissue samples were positive after day 7 and in 6 patients (8.6%) after day 10 when a blind subculture of the thioglycolate bro...

Clinical Microbiology and Infection, 1996

Objective: The susceptibilities t o penicillin, tetracycline, erythromycin, gentamicin, vancomyci... more Objective: The susceptibilities t o penicillin, tetracycline, erythromycin, gentamicin, vancomycin and teicoplanin of 58 strains of Corynebacterium jeikeium were assessed by disk diffusion and agar dilution reference methods. Methods: Zone sizes and minimal inhibitory concentrations (MIC) by agar dilution were interpreted using the ranges in the NCCLS tables for organisms other than Haemophilus, Neisseria gonorrhoeae, and Streptococcus pneumoniae. Results: By agar dilution, 14%, 88%, 17% and 26% of the 58 isolates were susceptible t o penicillin, tetracycline, erythromycin, and gentamicin, respectively. Using the breakpoints for Listeria monocytogenes, all strains showed concordant results for penicillin by disk diffusion. Discrepancies in the interpretative categories by disk diffusion were found in four cases (two very major and two minor) for tetracycline, in nine (two very major, two major, and five minor) for erythromycin, and in 1 case (very major) for gentamicin. All 58 strains were susceptible t o vancornycin and teicoplanin by agar dilution and disk diffusion. The overall agreement of interpretative disk diffusion for all six antibiotics was 95.9%. In addition, all strains were susceptible to both glycopeptides by E-test. However, for vancomycin the MIC results in 58.6% were two log2 dilutions and in 1.7% more than two log2 dilutions higher by E-test than by agar dilution, whereas for teicoplanin agreement within one log2 dilution was 100%. Conclusions: Further evaluation of methodologies of disk diffusion is required t o obtain a better agreement for erythromycin and tetracycline. The criteria of the NCCLS for interpretation of disk diffusion are adequate for susceptibility testing of C. jeikeium to penicillin, gentamicin, vancomycin and teicoplanin.

Neonatology, 2014

Background: The use of probiotics as prophylaxis for necrotizing enterocolitis (NEC) in preterm i... more Background: The use of probiotics as prophylaxis for necrotizing enterocolitis (NEC) in preterm infants is being increasingly practised. Objective: We report, for the first time, a case series of 3 preterm, very-low-birth-weight (VLBW) infants who developed bacteremia with Bifidobacterium longum on probiotic therapy with Infloran® containing viable B. longum. Methods: We retrospectively reviewed data of 3 infants (of gestational age <30 weeks and birth weight <1,230 g). They were admitted to the neonatal intensive care unit. Clinical data were retrieved from their medical records. Results: In infants 1 and 2, B. longum was isolated from the blood cultures when they were on probiotic therapy with Infloran or shortly after, respectively, and was interpreted as transient bacteremia. The clinical presentation of these infants did not require antibiotic treatment after the isolation of B. longum. Infant 3 developed an NEC despite probiotic therapy with Infloran and the blood cultur...

Head & neck, Jan 18, 2014

The goal of this study was to evaluate prospectively the presence and impact of the gastric carci... more The goal of this study was to evaluate prospectively the presence and impact of the gastric carcinogen Helicobacter pylori in the upper aerodigestive tract. Previous studies suggested it could represent a risk factor for head and neck squamous cell carcinoma. Serology, rapid urease test, and quantitative polymerase chain reaction (qPCR) for H. pylori were performed in head and neck cancer patients (N=56) and cancer-free controls (N=90). Comparison between groups was done using logistic regression analysis. Rates of positive serology and rapid urease test did not differ between the two groups in logistic regression analysis (P=0.677 and P=0.633, respectively). Birth in a developing country and age above 50 years old were predictors of positive serology (P<0.001 and P=0.040, respectively). Using qPCR, no biopsy showed presence of H.pylori. This study challenges the concept that H. pylori may be a risk factor for head and neck squamous cell carcinoma. This article is protected by co...