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With the increase in antimicrobial resistance, fast reporting of antimicrobial susceptibility testing (AST) results is becoming increasingly important. EUCAST developed a method for rapid AST (RAST) directly from the broth of positive blood cultures (BC). Inhibition zones are read after 4, 6, and 8 h, with specific breakpoints per time point. We evaluated the RAST method based on EUCAST disk diffusion methodology with inoculation of BC broth using WASPLab® (inclusive Colibrí™ and Radian®). Forty-nine non-duplicate strains were tested: Escherichia coli n = 17, Klebsiella pneumoniae n = 7, Pseudomonas aeruginosa n = 4, Acinetobacter baumannii n = 2, Staphylococcus aureus n = 10, Enterococcus faecalis n = 6, and Enterococcus faecium n = 3. Results were compared to direct AST and standardized AST. Good categorical agreement was obtained at all time points for all groups, except P. aeruginosa. RAST cut-offs for extended-spectrum β-lactamase (ESBL)-producing Enterobacterales enabled the detection of all included ESBL isolates (n = 5) at all time points, except for 1 E. coli ESBL after 4 h. RAST cut-offs for carbapenemase-producing Enterobacterales enabled the detection of only one carbapenemase after 6 h. However, all carbapenemases (n = 3) were correctly detected after 8 h. Two methicillin-resistant S. aureus were included; both were correctly categorized as cefoxitin-resistant at 6 and 8 h. At 4 h, there was insufficient growth for inhibition zone interpretation. EUCAST RAST is a fast supplementary tool for direct AST of positive BC. WASPLab® provides a significant advantage as pictures are made automatically implicating that we are not strictly bound to the time points for inhibition zone interpretation.

The microbiome of the reproductive tract has been associated with (sub)fertility and it has been suggested that dysbiosis reduces success rates and pregnancy outcomes. The endometrial microbiome is of particular interest given the potential impact on the embryo implantation. To date, all endometrial microbiome studies have applied a metagenomics approach. A sequencing-based technique, however, has its limitations, more specifically in adequately exploring low-biomass settings, such as intra-uterine/endometrial samples. In this proof-of-concept study, we demonstrate the applicability of culturomics, a high-throughput culturing approach, to investigate the endometrial microbiome. Ten subfertile women undergoing diagnostic hysteroscopy and endometrial biopsy, as part of their routine work-up at Brussels IVF, were included after their informed consent. Biopsies were used to culture microbiota for up to 30 days in multiple aerobic and anaerobic conditions. Subsequent WASPLab®-assisted culturomics enabled a standardized methodology. Matrix-assisted laser desorption/ionization–time of flight mass spectrometry (MALDI-TOF MS) or 16S rRNA sequencing was applied to identify all of bacterial and fungal isolates. Eighty-three bacterial and two fungal species were identified. The detected species were in concordance with previously published metagenomics-based endometrial microbiota analyses as 77 (91%) of them belonged to previously described genera. Nevertheless, highlighting the added value of culturomics to identify most isolates at the species level, 53 (62.4%) of the identified species were described in the endometrial microbiota for the first time. This study shows the applicability and added value of WASPLab®-assisted culturomics to investigate the low biomass endometrial microbiome at a species level.

Background: Healthcare-associated SARS-CoV-2 infections need to be explored further. Our study is an analysis of hospital-acquired infections (HAIs) and ambulatory healthcare workers (aHCWs) with SARS-CoV-2 across the pandemic in a Belgian university hospital. Methods: We compared HAIs with community-associated infections (CAIs) to identify the factors associated with having an HAI. We then performed a genomic cluster analysis of HAIs and aHCWs. We used this alongside the European Centre for Disease Control (ECDC) case source classifications of an HAI. Results: Between March 2020 and March 2022, 269 patients had an HAI. A lower BMI, a worse frailty index, lower C-reactive protein (CRP), and a higher thrombocyte count as well as death and length of stay were significantly associated with having an HAI. Using those variables to predict HAIs versus CAIs, we obtained a positive predictive value (PPV) of 83.6% and a negative predictive value (NPV) of 82.2%; the area under the ROC was 0.89. Genomic cluster analyses and representations on epicurves and minimal spanning trees delivered further insights into HAI dynamics across different pandemic waves. The genomic data were also compared with the clinical ECDC definitions for HAIs; we found that 90.0% of the ‘definite’, 87.8% of the ‘probable’, and 70.3% of the ‘indeterminate’ HAIs belonged to one of the twenty-two COVID-19 genomic clusters we identified. Conclusions: We propose a novel prediction model for HAIs. In addition, we show that the management of nosocomial outbreaks will benefit from genome sequencing analyses.

BackgroundWorldwide, healthcare-associated SARS-CoV-2 infections are a major problem: they are associated with increased morbidity, mortality, and hospitalization costs. In-depth studies across the pandemic are crucial to understand and prevent transmission in hospital settings. The principal aims of this study were to characterise patients and validate ECDC definitions of healthcare-associated COVID-19 infections.MethodsWe set up a retrospective observational study spanning the first three waves of the COVID-19 pandemic in a Belgian university hospital: it describes the characteristics of COVID-19 patients admitted, with either healthcare- or community-associated infections. We performed a cluster analysis through epidemiological and viral genome analyses of the healthcare-associated infections, in order to validate the ECDC definitions of healthcare-associated COVID-19 infections.ResultsBetween week 10 of 2020 and week 22 of 2021, 168 patients were hospitalized with healthcare-associated COVID-19. The following factors were found more often in symptomatic healthcare- than in community-associated hospitalized patients: older age, increased frailty, smoking habits, and comorbidities. The genome-based cluster analyses showed that different viral lineages predominated in different timeframes. We observed a good correlation of epidemiological data with genome sequencing results in at least 12 different outbreaks in our hospital, thus validating the ECDC definitions. ConclusionsThis in-depth characterization sheds new light on the problem of healthcare-associated COVID-19 infections, in particular on patients’ characteristics, epidemiology, and cluster dynamics. Even though epidemiological evaluation of nosocomial infections is vital, management of nosocomial outbreaks can undoubtedly benefit from genome sequencing analyses to reinforce their strategy.

In Western Europe, the incidence of both respiratory and cutaneous diphtheria, caused by toxin-producing Corynebacterium diphtheriae, Corynebacterium ulcerans or Corynebacterium pseudotuberculosis, has been low over the past few decades thanks to the use of an effective vaccine and a high level of vaccination coverage. However, the disease has still not been eradicated and continues to occur in all of Europe. In order to prevent sequelae or a fatal outcome, diphtheria antitoxin (DAT) should be administered to suspected diphtheria patients as soon as possible, but economic factors and issues concerning regulations have led to poor availability of DAT in many countries. The European Centre for Disease Prevention and Control and World Health Organization have called for European Union-wide solutions to this DAT-shortage. In order to illustrate the importance of these efforts and underline the need for continued diphtheria surveillance, we present data on all registered cases of toxigenic and non-toxigenic C. diphtheriae, C. ulcerans and C. pseudotuberculosis in Belgium during the past decade, up to and including 2017.

Background/aimsSARS-CoV-2 is highly contagious. More evidence concerning extrapulmonary transmission routes such as the eyes is urgently needed. Although the humoral immune response is important in the viral containment, the local response in tears has not yet been studied. The aim of our study was twofold: to assess the prevalence of both SARS-CoV-2 RNA and antibodies in tear fluid.MethodsIn a first series, nasopharyngeal sampling and tear sampling by Schirmer test strips were performed in 26 acutely ill patients with COVID-19 to assess the presence of SARS-CoV-2 RNA by reverse transcription PCR. In a second series, IgG and IgA responses to SARS-CoV-2 spike protein in serum and tear fluid of convalescent individuals (n=22) were compared with control individuals (n=15) by ELISA.ResultsSARS-CoV-2 RNA was detected in tears of 7/26 (26.9%) patients with COVID-19. None of them had ocular symptoms. Convalescent individuals displayed a significant higher ratio of IgG (pConclusionsOur results demonstrate the presence of SARS-CoV-2 RNA and a local IgG and IgA immune response in tear fluid. These data confirm the possibility of SARS-CoV-2 transmission through tear fluid and the importance of the eye as a first defence against SARS-CoV-2, indicating the potential of tears as a non-invasive surrogate for serum in monitoring the host immune response.

Summary Background Serratia marcescens is notorious for its increasing antimicrobial resistance and potential to cause outbreaks in neonatal intensive care units (NICUs). A promising tool in outbreak investigations is whole-genome sequencing (WGS). Objectives To describe a S. marcescens outbreak (2018–2019) in an NICU and discuss which infection control measures contributed to containment, addressing the potential of WGS. Methods S. marcescens isolates from patients and the environment isolated during the 2018–2019 NICU outbreak were analysed. In comparison, isolates from previous presumed NICU outbreaks and adult blood cultures were included. WGS and whole-genome multi-locus sequence typing analysis were performed. Results Sixty-three S. marcescens isolates were analysed. The 2018–2019 outbreak was divided into three clusters, including four environmental strains (drains, N=3; baby scale, N=1). The strains differed significantly from those of an NICU outbreak in 2014 and adult blood cultures. Besides standard infection control measures, the siphons were replaced and weekly decontamination was performed with acetic acid 10%. Seven acquired-resistance genes and 29 virulence-associated genes were detected. Conclusions It was assumed that both neonates and drains were reservoirs of S. marcescens cross-contamination via the hands of healthcare workers and parents. Initially, standard measures, including hand hygiene, were reinforced. However, definitive containment was achieved only after replacement of the siphons and weekly decontamination with acetic acid. WGS enables faster recognition of an outbreak with accurate mapping of the spread, facilitating the implementation of infection control measures. WGS also provides interesting information about the spread of antibiotic resistance and virulence genes.

A cluster of Legionnaires' disease (LD) with 10 confirmed, three probable and four possible cases occurred in August and September 2016 in Dendermonde, Belgium. The incidence in the district was 7 cases/100 000 population, exceeding the maximum annual incidence in the previous 5 years of 1.5/100 000. Epidemiological, environmental and geographical investigations identified a cooling tower (CT) as the most likely source. The case risk around the tower decreased with increasing distance and was highest within 5 km.Legionella pneumophilaserogroup 1, ST48, was identified in a human respiratory sample but could not be matched with the environmental results. Public health authorities imposed measures to control the contamination of the CT and organised follow-up sampling. We identified obstacles encountered during the cluster investigation and formulated recommendations for improved LD cluster management, including faster coordination of teams through the outbreak control team, improved communication about clinical and environmental sample analysis, more detailed documentation of potential exposures obtained through the case questionnaire and earlier use of a geographical information tool to compare potential sources and for hypothesis generation.

Here, we sought to assess the levels of antibiotic resistance among intestinal Bacteroides and Parabacteroides strains collected between 2014 and 2016 in Europe and also attempted to compare resistance levels between clinical and commensal isolates. Bacteroides and Parabacteroides isolates were recovered from faecal samples via the novel Bacteroides Chromogenic Agar (BCA) method. Antibiotic susceptibilities were determined by agar dilution for ten antibiotics. The values obtained were then statistically evaluated. Altogether 202 Bacteroides/Parabacteroides isolates (of which 24, 11.9%, were B. fragilis) were isolated from the faecal specimens of individuals taken from five European countries. The percentage values of isolates resistant to ampicillin, amoxicillin/clavulanate, cefoxitin, imipenem, clindamycin, moxifloxacin, metronidazole, tetracycline, tigecycline and chloramphenicol were 96.6, 4.5, 14.9, 2.0, 47.3, 11.4, 0, 66.2, 1.5 and 0%, respectively. These values are close to those reported in the previous European clinical Bacteroides antibiotic susceptibility survey except for amoxicillin/clavulanate and clindamycin, where the former was lower and the latter was higher in normal microbiota isolates. To account for these latter findings and to assess temporal effects we compared the data specific for Hungary for the same period (2014-2016), and we found differences in the resistance rates for cefoxitin, moxifloxacin and tetracycline. (C) 2020 Elsevier Ltd. All rights reserved.

Fusobacterium nucleatum is anaerobic oral microbiota that might be associated with cancer. We reported 22 consecutive cases of patients (mean age of 63.8 years (range 34–89), 59.1% male) with F . nucleatum bacteremia that were admitted to a university hospital over a 10-year period. In 17 (77.2%) of these patients, F . nucleatum was the sole possible pathogen. Seven of the 22 patients (31.8%) had active cancer: esophagus carcinoma (n = 3), hematologic malignancies (n = 1), gastrointestinal stromal tumor (n = 1), melanoma (n = 1), and breast cancer (n = 1). In six out of seven patients (85.7%), the F . nucleatum was found within six months of the diagnosis of cancer. Four of seven (57.1%), patients with cancer were on chemotherapy. Three of 22 patients (13.4%) died within 1 month of F . nucleatum bacteremia due to cancer. In conclusion, F . nucleatum bacteremia occurs rarely and when it is found, it is often in patients with cancer, especially those with a recent diagnosis.

Background Carbapenemase-producing Enterobacteriaceae (CPE) are emerging pathogens that represent a major public health threat. In the University Hospital of Brussels, the incidence of new patients with CPE rose from 1 case in 2010 to 35 cases in 2015. Between January and August 2015, five patients became infected/colonized with CPE during their stay in the same room in the intensive care unit (ICU). Since the time period between those patients was relatively short and the strains belonged to different species with different antibiograms and mechanisms of resistance, the hypothesis was that the environment could be a possible source of transmission. Methods and results Environmental samples suggested that a contaminated sink was the source of the outbreak. Besides other strains, Citrobacter freundii type OXA-48 was frequently isolated from patients and sinks. To investigate the phylogenetic relationschip between those strains, pulsed-field gel electrophoresis was performed. The strains isolated from patients and the sink in the implicated room were highly related and pointed to sink-to-patient transmission. In total, 7 of 8 sinks in the isolation rooms of the ICU were found to be CPE contaminated. To control the outbreak, the sinks and their plumbings were replaced by new ones with another structure, they were flushed every morning with a glucoprotamin solution and routines regarding sink practices were improved leading to discontinuation of the outbreak. Conclusions This outbreak highlights that hospital sink drains can accumulate strains with resistance genes and become a potential source of CPE.

The performance of matrix-assisted laser desorption–ionization time of flight mass spectrometry (MALDI-TOF MS) for species identification of Prevotella was evaluated and compared with 16S rRNA gene sequencing. Using a Bruker database, 62.7% of the 102 clinical isolates were identified to the species level and 73.5% to the genus level. Extension of the commercial database improved these figures to, respectively, 83.3% and 89.2%. MALDI-TOF MS identification of Prevotella is reliable but needs a more extensive database.

In order to identify current trends in anaerobic bacteraemia, a 10-year retrospective study was performed in the University Hospital Brussel, Belgium. All clinically relevant bacteraemia detected from 2004 until 2013 were included. Medical records were reviewed in an attempt to define clinical parameters that might be associated with the occurrence of anaerobic bacteraemia. 437 of the isolated organisms causing anaerobic bacteraemia were thawed, subcultured and reanalyzed using matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF). There were an average of 33 cases of anaerobic bacteraemia per year during 2004–2008 compared to an average of 27 cases per year during 2009–2013 (P = 0.017), corresponding to a decrease by 19% between the first and the latter period. Also, the total number of cases of anaerobic bacteraemia per 100,000 patient days decreased from 17.3 in the period from 2004 to 2008 to 13.7 in the period 2009 to 2013 (P = 0.023). Additionally, the mean incidence of anaerobic bacteraemia decreased during the study period (1.27/1000 patients in 2004 vs. 0.94/1000 patients in 2013; P = 0.008). In contrast, the proportion of isolated anaerobic bacteraemia compared to the number of all bacteraemia remained stable at 5%. Bacteroides spp. and Parabacteroides spp. accounted for 47.1% of the anaerobes, followed by 14.4% Clostridium spp., 12.6% non-spore-forming Gram-positive rods, 10.5% anaerobic cocci, 8.2% Prevotella spp. and other Gram-negative rods and 7.1% Fusobacterium spp. The lower gastrointestinal tract (47%) and wound infections (10%) were the two most frequent sources for bacteraemia, with the origin remaining unknown in 62 cases (21%). The overall mortality rate was 14%. Further studies focusing on the antimicrobial susceptibility and demographic background of patients are needed to further objectify the currently observed trends.

Carbapenem resistance in Bacteroides fragilis is associated with cfiA -encoded class B metallo-beta-lactamase. cfiA -negative and cfiA -positive isolates belong to genotypically distinct groups. Of a total of 248 B. fragilis isolates included in this study, 214 were susceptible, 10 were intermediate, and 24 were resistant to meropenem. We show that matrix-assisted laser desorption ionization–time of flight mass spectrometry is able to differentiate between cfiA -negative and cfiA -positive isolates and predict carbapenem resistance in a routine laboratory setting.

Recently new resin-based BacT/Alert FAN Plus bottles containing antibiotic-binding polymeric beads, were introduced as an improvement of the charcoal-based FAN bottles for the recovery of bacteria and fungi. To assess the performance of the novel anaerobic FN plus bottles in the detection of anaerobic organisms, we compared the detection rate and the time to detection (TTD) in spiked resin-based FN Plus bottles and charcoal-based FN bottles. The bottles were experimentally seeded with reference strains or clinical strains collected from positive blood cultures. Five reference strains and fifty-five clinically significant anaerobic isolates were investigated, of which 91% (61/67) showed growth in both types of bottles within an incubation time of 5 days. A significant prolonged median TTD of 45 h for anaerobic microorganisms was observed in the resin-based bottles versus 29 h in the charcoal-based bottles (P

Background Fusobacterium spp. from clinical specimens are increasingly reported. We sought to describe the epidemiology, the microbiological, and the clinical characteristics of head and neck infections caused by Fusobacterium necrophorum and other Fusobacterium spp. Materials and methods Retrospective cohort study between October 1st, 2004 and September 30th, 2014 performed in an academic hospital. Electronic patient charts and the laboratory information system were reviewed for demographic and microbiological data. The number and percentages of specific diagnosis and treatment among patients with positive Fusobacterium spp. culture were calculated. The incidence was calculated based on the number of specimens investigated each year. Results Included were 230 cultures of 230 patients (median age of 28 years, 61.7% men). F. necrophorum was often found in young patients with high C-reactive protein (CRP) and high number of leukocytes in blood. Other Fusobacterium spp. were often found in middle aged patients with relatively high CRP and slightly increased leukocytes. Three major causes of the isolation of F. necrophorum and other Fusobacterium spp. were acute tonsillitis (n = 18, incidence of 0.2%), peritonsillar abscess (n = 39, 0.5%) and acute otitis (n = 45, 0.1%). While F. necrophorum was found in majority (37/57) of patients with acute tonsillitis or peritonsillar abscess, Fusobacterium spp. other than F. necrophorum were found in the majority (35/45) of patients with acute otitis. Isolated fusobacteria were susceptible to beta-lactam antibiotics, clindamycin and metronidazole. The outcomes of patients with Fusobacterium spp. were good. Conclusion F. necrophorum and other Fusobacterium spp. are rare cause of head and neck infections. The infections are well treated by combination of antibiotics and surgery.

Reptile-associated salmonellosis in humans is an increasing public health issue. This study aimed at characterizing Salmonella isolates from captive lizards and to compare them to human isolates. Salmonella was isolated from 25 of 33 cloacal and 47 of 79 faecal samples from captive lizards (75.8 and 59.5%, respectively). The strains belonged to 44 serotypes of subspecies I (27 serotypes), II (9), IIIb (3) and IV (5). Two strains, one of serotype Enteritidis and one of serotype Amsterdam, were resistant to nitrofurantoin. Invasion assays in Caco-2 cells were performed with 40 saurian isolates of subspecies I, 15 isolates of subspecies II, 4 strains of subspecies IIIb, 6 subspecies IV isolates and 17 human isolates of corresponding serotypes of subspecies I. Saurian isolates belonging to subspecies I invaded the Caco-2 cells to a higher extent than those from the other subspecies. The human isolates invaded the Caco-2 cells to a lesser degree compared to their saurian counterparts. In the same strains, the presence of virulence genes agfA, shdA, spvR, pefA and sopE was determined using PCR. Whereas agfA was detected in all strains, pefA was only detected in one saurian and in the human serotype Enteritidis strains. The spvR gene was detected in the same serotype Enteritidis strains and in 33% of the subspecies IV strains. The shdA gene was present in all the human isolates and in 86% of subspecies I saurian isolates. SopE was found in 17% of the human isolates, in 24% of the saurian subspecies I strains and in all of the subspecies IV strains.

No abstract available

L'ertapeneme est un nouveau carbapeneme a usage parenteral avec une demi-vie serique prolongee. Son spectre d'activite est similaire a celui de l'imipeneme et du meropeneme a l'egard des bacteries a Gram positif, des enterobacteries, et des bacilles a Gram negatif fastidieux mais son activite est moindre sur Pseudomonas aeruginosa et Acinetobacter spp. Plusieurs etudes americaines mais seulement une etude europeenne ont montre que l'ertapeneme a une excellente activite sur les anaerobies. Les objectifs de cette etude etaient de tester l'activite de l'ertapeneme vis-a-vis d'anaerobies isoles de facon prospective des tractus respiratoires bas et haut, et de comparer leur susceptibilite a celle d'isolats anaerobies provenant d'autres sites. Cinquante-trois (53) isolats du tractus respiratoire ainsi que 50 isolats d'autres sites corporels ont ete testes a l'aide d'E-tests pour 6 antibiotiques. Pour les isolats respiratoires et ceux d'autres sites les CMI 90 (mg/L) etaient respectivement > 32 et > 32 pour la penicilline, 0,38 et 0,75 pour l'association amoxicilline-clavulanate, 48 et > 256 pour la ceftriaxone, 0,12 et 0,75 pour l'ertapeneme, 12 et > 256 pour la clindamycine et 2 et 12 pour la moxifloxacine. La sensibilite superieure des isolats respiratoires etait principalement due a la distribution differente des especes isolees: seulement 3 isolats respiratoires mais 22 autres isolats appartenaient au groupe de Bacteroides fragilis. Cette etude confirme l'excellente activite de l'ertapeneme vis-a-vis des anaerobies du tractus respiratoire.

Corynebacterium diphtheriae and Corynebacterium ulcerans are rarely isolated from clinical samples in Belgium. A case of toxigenic C. ulcerans in a woman is described, which confirms that this pathogen is still present. During investigation of the patient's cats, only a non-toxigenic toxin-bearing C. diphtheriae strain was detected.

Sequence-based typing (SBT) is a discriminatory method widely used to genotype Legionella pneumophila strains. A total of 86 clinical L. pneumophila serogroup 1 (sg1) isolates, collected between January 2000 and December 2010 in the two Belgian National Reference Centres for Legionella pneumophila, were genotyped using the internationally standardised SBT protocol of the European Working Group for Legionella Infections (EWGLI). The isolates could be classified into 31 different sequence types (ST, index of diversity: 0.879). The obtained STs were submitted to the EWGLI SBT-database for L. pneumophila. In our study, ST47 (27.9%) and ST1 (19.8%) were the most frequently detected STs. The detected profiles were a combination of both frequently isolated and unique STs, and of both worldwide distributed and more local strains. Two STs, ST880 and ST881, were new to the EWGLI database. In conclusion, we characterised L. pneumophila sg1 isolates with the SBT method, and created a Belgian profile database that will be useful for future epidemiological studies.

Reptile-associated salmonellosis in humans is an increasing public health issue. This study aimed at characterizing Salmonella isolates from captive lizards and to compare them to human isolates. Salmonella was isolated from 25 of 33 cloacal and 47 of 79 faecal samples from captive lizards (75.8 and 59.5%, respectively). The strains belonged to 44 serotypes of subspecies I (27 serotypes), II (9), IIIb (3) and IV (5). Two strains, one of serotype Enteritidis and one of serotype Amsterdam, were resistant to nitrofurantoin. Invasion assays in Caco-2 cells were performed with 40 saurian isolates of subspecies I, 15 isolates of subspecies II, 4 strains of subspecies IIIb, 6 subspecies IV isolates and 17 human isolates of corresponding serotypes of subspecies I. Saurian isolates belonging to subspecies I invaded the Caco-2 cells to a higher extent than those from the other subspecies. The human isolates invaded the Caco-2 cells to a lesser degree compared to their saurian counterparts. In the same strains, the presence of virulence genes agfA, shdA, spvR, pefA and sopE was determined using PCR. Whereas agfA was detected in all strains, pefA was only detected in one saurian and in the human serotype Enteritidis strains. The spvR gene was detected in the same serotype Enteritidis strains and in 33% of the subspecies IV strains. The shdA gene was present in all the human isolates and in 86% of subspecies I saurian isolates. SopE was found in 17% of the human isolates, in 24% of the saurian subspecies I strains and in all of the subspecies IV strains.

Infantile Refsum's disease is characterized by high levels of phytanic acid and the absence of normal hepatic peroxisomes. We investigated the in vivo influence of phytol, a precursor of phytanic acid, on peroxisomes by both biochemical and morphological methods. Enhanced supply of phytol in the diet of adult mice causes proliferation of hepatic peroxisomes. The peroxisomal β-oxidizing capacity as well as exchanges of acyl moieties between peroxisomes and mitochondria are raised around 5- and 2- fold, respectively. In parallel a 1.5-fold increase of total catalase and mitochondrial butyryl-CoA dehydrogenase activities occurs, whereas peroxisomal urate oxidase and glycolate oxidase remain normally active. Serum triglyceride levels are decreased after 3 wk of phytol feeding; serum cholesterol levels remain unaffected. Phytol feeding also induces peroxisome proliferation in duodenal epithelium, in myocardium and in skin sebaceous glands, but not in kidney.

The Vitek 2 Anaerobe and Corynebacterium Identification Card (ANC) was recently evaluated in a multicentre study. In the present work, this system was compared with the BBL Crystal Anaerobe and RapID ANA II panels. These kits were tested using 196 strains of anaerobes that had been previously identified by gas-liquid chromatography. Identification to the species or to the genus level was 75.0%, 81.1% and 70.9% for Crystal, RapID and Vitek, respectively. Vitek ANC failed to provide any identification in 20.4% of the strains, but it had fewer misidentifications than RapID. The confidence factors provided on the results report of each kit were not always correlated with a lower risk of major errors, with the exception of Vitek 2 in which a confidence factor higher than 0.86 excluded the risk of misidentification in more than 87% of isolates. The lower rate of identification by the Vitek and Crystal panels is mostly due the lower ability of these systems to identify the Clostridia. Overall, the three panels are comparable but need improvement to a better accuracy.

With the increase in antimicrobial resistance, fast reporting of antimicrobial susceptibility testing (AST) results is becoming increasingly important. EUCAST developed a method for rapid AST (RAST) directly from the broth of positive blood cultures (BC). Inhibition zones are read after 4, 6, and 8 h, with specific breakpoints per time point. We evaluated the RAST method based on EUCAST disk diffusion methodology with inoculation of BC broth using WASPLab

In order to assess antimicrobial resistance in nontyphoid human Salmonella in Belgium, the six most important serovars, representing together more than 90% of laboratory confirmed cases, were randomly sampled. From June 2000 until December 2002, a total of 1756 isolates were screened for their antimicrobial resistance profile by the disc diffusion method. S. Hadar strains showed the highest level of antimicrobial resistance. Simultaneous resistance to ampicillin, nalidixic acid, tetracycline and streptomycin was observed in 81.5, 58 and 76.1% of these isolates in 2000, 2001 and 2002, respectively. All S. Hadar isolates resistant to nalidixic acid also displayed decreased susceptibility to ciprofloxacin (MIC50 values of 0.25 microg/mL in 2000-2001 and 0.19 microg/mL in 2002). In 2000, 2001 and 2002, respectively 44.6, 46 and 36.5% of S. Typhimurium isolates were multiresistant (resistant to 4 or more antimicrobial agents). These multiresistant isolates were preferably associated with a few phage types, such as DT104. Complete resistance to ciprofloxacin was detected in three S. Typhimurium isolates and sequencing of the gyrA gene revealed for each isolate two mutations at codons corresponding to Ser-83 and Asp-87. Multiresistance was also common in S. Virchow (7.7%, 15.9% and 29.7%, in 2000, 2001 and 2002, respectively). Resistance to nalidixic acid in S. Virchow isolates increased from 46.2% in 2000 to 80.9% in 2002 and six S. Virchow isolates were detected as cefotaxime resistant. In contrast, the vast majority of S. Enteritidis, S. Brandenburg and S. Derby isolates remained sensitive to almost all antimicrobial agents tested.

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This study compared the performance of three matrix-assisted laser desorption ionization–time of flight mass spectrometry systems: Microflex LT (Bruker Daltonics, Bremen, Germany), Vitek MS RUO (Axima Assurance-Saramis database; bioMérieux, Marcy l'Etoile, France), and Vitek MS IVD (bioMérieux). A total of 1,129 isolates, including 1,003 routine isolates, 73 anaerobes, and 53 bacterial enteropathogens, were tested on the Microflex LT and Axima Assurance devices. The spectra were analyzed using three databases: Biotyper (Bruker Daltonics), Saramis, and Vitek MS (bioMérieux). Among the routine isolates requiring identification to the species level ( n = 986), 92.7% and 93.2% were correctly identified by the Biotyper and Vitek MS databases, respectively. The Vitek MS database is more specific for the identification of Streptococcus viridans . For the anaerobes, the Biotyper database often identified Fusobacterium isolates to only the genus level, which is of low clinical significance, whereas 20% of the Bacteroides species were not identified or were misidentified by the Vitek MS database. For the enteropathogens, the poor discrimination between Escherichia coli and Shigella explains the high proportion of unidentified organisms. In contrast to the Biotyper database, the Vitek MS database properly discriminated all of the Salmonella entrica serovar Typhi isolates ( n = 5). The performance of the Saramis database was globally poorer. In conclusion, for routine procedures, the Microflex LT and Vitek-MS systems are equally good choices in terms of analytical efficiency. Other factors, including price, work flow, and lab activity, will affect the choice of a system.

Multidrug-resistant (MDR) Acinetobacter baumannii are emerging as important nosocomial pathogens. These organisms have a capacity for long-term survival in the hospital environment. The purpose of this study was to describe the course and control of an outbreak with MDR A. baumannii in a Belgian university hospital after transfer of two trauma patients from Greece. Wounds in both patients were colonised with MDR A. baumannii. Over an 11 month period from September 2004 to July 2005, carbapenem-non-susceptible A. baumannii (producing carbapenem-hydrolysing oxacillinase OXA-58) were isolated from 28 patients, despite early implementation of contact precautions. MDR A. baumannii was detected in routine clinical diagnostic samples from 26 patients and in screening specimens from an additional two patients. Twenty patients (71.4%) were colonised or infected during their stay in intensive care. Twenty-four (85.7%) respiratory samples were positive for MDR A. baumannii. Careful review of all procedures related to the respiratory tract did not identify a common route of transmission. Outbreak control required multiple interventions, including contact isolation of colonised and infected patients, monitoring the practice of personnel, screening of asymptomatic patients, use of isolation rooms and enhanced environmental disinfection. Introduction of single-use ventilator circuits was considered but the outbreak was controlled before implementation.