Evaluation of the knowledge on alveolar echinococcosis among general practitioners in the province of Liege : impact of a formative intervention

editorial reviewedL’échinococcose alvéolaire est une zoonose autochtone provoquée par le développement tissulaire de la larve d’un petit ténia, Echinoccocus multilocularis. Mal- gré une faible incidence en Belgique, avec une moyenne de 10 cas recensés par an, cette parasitose pose un réel problème de santé publique car elle reste souvent difficile à diagnostiquer et potentiellement mortelle en l’absence de traitement. Les médecins généralistes sont en première ligne, mais ils ne connaissent pas toujours suffisamment la maladie, ce qui retarde le diagnostic et compromet le pronostic. La présente étude visait à évaluer les connaissances à propos de l’échinococcose alvéolaire des médecins généralistes de la province de Liège via un questionnaire approprié et à accroître leur niveau de connaissance via une intervention formative sous forme de capsule vidéo. Nous avons réalisé une étude à visée expérimentale randomisée contrôlée qui a montré que les médecins généralistes de la province de Liège ont des connaissances partielles sur la symptomatologie, les outils de diagnostic et le traitement. L’intervention formative réa- lisée a permis d’augmenter leur niveau de connaissances à propos de cette maladie.Alveolar echinococcosis is an indigenouszoo- nosis caused by the growth of the larval stage of a small tapeworm, Echinococcus multilocularis. Despite a low inci- dence in Belgium, with about 10 cases on average recorded per year, this parasitosis poses a real public health pro- blem because it often remains difficult to diagnose and is potentially fatal in the absence of treatment. General prac- titioners are on the frontline, but they do not always know enough about the disease, which causes a delay in the diagnosis and impacts the prognosis. The present study aims to assess the level of knowledge of alveolar echino- coccosis among general practitioners in the province of Liège via a questionnaire, on the one hand, and to increase their level of knowledge via a formative intervention using a video capsule, on the other hand. We have performed a randomized controlled experimental study, which showed that general practitioners in the province of Liège have limited knowledge on alveolar echinococcosis. This mainly concerns symptomatology, diagnostic tools and treatment. The formative intervention carried out allowed increasing their level of knowledge about this disease

Evaluation of Whole-Genome Sequencing combined with a bioinformatics tool for the complete characterization of Streptococcus agalactiae infection

peer reviewedBackground: Our aim was to evaluate the Whole-Genome Sequencing (WGS), as a new tool, in order to implement the method within the activities of the Belgian National Reference Centre Streptococcus agalactiae (NRC). The analysis of the bacterial genome by WGS could replace some current standard methods used at the NRC, unifying laboratory workflow, diminishing workload, enhancing molecular surveillance. Methods: To determine the reliability of the WGS, the results were compared with those obtained by the standard methods used by the NRC (multiplex PCRs and MLST). The raw sequence data from WGS were analyzed with the bioinformatics tool "WGS-typer" (Hedera22, Liège, Belgium), specially designed for the NRC needs. 37 strains isolated from vaginal colonization, or invasive infections in adults and infants were selected for their varied characteristics from the NRC collection. Capsular serotype, pili proteins genes, macrolides/lincosamides/streptogramins (MLS) resistance genes and sequence types were determined by both approaches. Results: Regarding capsular serotype and pili protein genes, the results reported by conventional PCR methods were perfectly confirmed by the WGS (100% concordance). However, for MLS resistance genes and sequence types, the comparison highlights one and three discrepancies respectively. A new sequence type 1655 was listed in the PUBMLST database thanks to this research. Conclusion: WGS is a promising approach that can compete with the conventional methods currently used in laboratories. Indeed, this technology allows, at lower costs and workload, a complete characterization of the GBS and a huge concordance between WGS and conventional methods has been observed

Evaluation of a commercial IgG monotest assay: a new automated chemiluminescent immunoassay for the serodiagnosis of cystic echinococcosis

Background: Cystic echinococcosis (CE) is a zoonotic disease caused by the tapeworm Echinococcus granulosus complex. The geographical distribution is worldwide with variable incidences. In Belgium, only few imported cases are reported each year. Serodiagnosis of CE is performed by using a combination of immunoassays which are mainly based on crude hydatid antigens. The Belgian National Reference Laboratory, has evaluated the CE-IVD Hydatidosis VirClia® IgG chemiluminescent immunoassay and compared it with two other immunoassays. Methods: A total of 79 sera were retrospectively included from 15 patients with CE, 29 with alveolar echinococcosis, 16 with toxocariasis and 19 negative controls. Three immunoassays were compared: the Hydatidosis VirClia® IgG monotest assay which was run on the Virclia® Lotus (Vircell, Spain); the Ridascreen® Echinococcus IgG assay (R-Biopharm, Germany) and the Bordier® Echinococcus granulosus IgG ELISA (Bordier, Switzerland), which were tested on the ETI-Max 3000 immunoassay analyzer (DiaSorin, Italy). The McNemar test is used for statistical analysis. Results: All three methods showed 100% sensitivity. Regarding specificity, the Ridascreen® (78.1%) and VirClia® (76.6%) assays showed comparable performance (p-value: 1), while the Bordier® assay had poor results (54,7%) (p-value: 0,0007). The Bordier® assay showed 76% cross-reactions with E. multilocularis (22/29) and 31% with Toxocara sp. (5/16), while the VirClia® assay showed 51,7% (15/29) and no cross-reaction with Toxocara antigens. For Ridascreen® assay, 34% and 19% cross-reactions were observed for E. multilocularis (10/29) and Toxocara sp. (3/16), respectively. Non-specific reactions in negative controls were only observed with the Ridascreen® (1/19) and Bordier® assays (2/19). The shortest turnaround time was observed with Virclia® Lotus: 1 hour versus 3 hours for two other assays. Conclusions: All assays showed very high sensitivity. However, regarding specificity, the VirClia® performs better than the Bordier® and similarly to the Ridascreen® assay. Besides, the ready-to-use monotest format offers many advantages such as a quicker methodology and a reduced workflow. Therefore, the VirClia® assay is an efficient screening method for the detection of CE but should always be combined with an immunoblot assay to assess the specificity

Genetic diversity of Echinococcus multilocularis specimens isolated from Belgian patients with alveolar echinococcosis using EmsB microsatellites analysis.

The genetic diversity of Echinococcus multilocularis (E. multilocularis) specimens isolated from patients with alveolar echinococcosis (AE), is a major field of investigation to correlate with sources of infection, clinical manifestations and prognosis of the disease. Molecular markers able to distinguish samples are commonly used worldwide, including the EmsB microsatellite. Here, we report the use of the EmsB microsatellite polymorphism data mining for the retrospective typing of Belgian specimens of E. multilocularis infecting humans. A total of 18 samples from 16 AE patients treated between 2006 and 2021 were analyzed through the EmsB polymorphism. Classification of specimens was performed through a dendrogram construction in order to compare the similarity among Belgian samples, some human referenced specimens on the EWET database (EmsB Website for the Echinococcus Typing) and previously published EmsB profiles from red foxes circulating in/near Belgium. According to a comparison with human European specimens previously genotyped in profiles, the 18 Belgian ones were classified into three EmsB profiles. Four specimens could not be assigned to an already known profile but some are near to EWET referenced samples. This study also highlights that some specimens share the same EmsB profile with profiles characterized in red foxes from north Belgium, the Netherlands, Luxembourg and French department near to the Belgian border. Furthermore, Belgian specimens present a genetic diversity and include one profile that don't share similarities with the ones referenced in the EWET database. However, at this geographical scale, there is no clear correlation between EmsB profiles and geographical location. Further studies including additional clinical samples and isolates from foxes and rodents of south Belgium are necessary to better understand the spatial and temporal circumstances of human infections but also a potential correlation between EmsB profiles and parasite virulence

Use of supercritical CO2 for the sterilization of liposomes: Study of the influence of sterilization conditions on the chemical and physical stability of phospholipids and liposomes.

peer reviewedThe effects of four potential supercritical carbon dioxide (ScCO2) sterilization conditions on the chemical stability of 9 phospholipids and on the physicochemical characteristics of liposomes consisting of stable phospholipids, as well as their sterilization efficiency were evaluated. These conditions were : C1 (ScCO2/70 °C/150 bar/240 min), C2 (ScCO2/0.25 % water/ 0.15% H2O2/ 0.5% acetic anhydride/38° C/85 bar/45 min), C3 (ScCO2/0.08 % peracetic acid/35° C/104 bar/180 min) and C4 (ScCO2/200 ppm H2O2/40 °C/270 bar/90 min). The results showed for phospholipids, a significant increase in hydrolysis products of 3.77 to 14.50 % and an increase in oxidation index of 6.10 to 430.50 % with unsaturated phospholipids for all tested conditions while with saturated phospholipids, no significant degradation was observed. Concerning the liposome formulation, no change in dispersion color and no phospholipid degradation were observed. However, a decrease in liposome size from 126.90 nm to 111.80 nm, 96.27 nm, 99.60 nm and 109.13 nm and an increase in the PdI from 0.208 to 0.271, 0.233, 0.285, and 0.298 were found with conditions C1, C2, C3 and C4 respectively. For the sterilization efficiency, conditions C1, C2 and C3 achieved the required sterility assurance level (SAL) of 10-6 for liposomes

C32 Développement d’un procédé de production et de stérilisation de liposomes en une seule étape en utilisant le dioxyde de carbone supercritique

Introduction : les liposomes sont des vecteurs ciblés de médicaments présentant aujourd’hui un grand intérêt pharmaceutique et thérapeutique et généralement administrés par voie parentérale. Cependant, leur fabrication industrielle ainsi que leur stérilisation demeurent un défi. Le dioxyde de carbone supercritique (CO2Sc) constitue aujourd’hui une méthode alternative de production des liposomes et présente également des propriétés stérilisantes. Le but de ce travail est de développer un procédé innovant de production et de stérilisation des liposomes en une seule étape en utilisant le ScCO2. Méthodologie : la capacité de 4 conditions ScCO2 à atteindre le niveau d’assurance de stérilité (SAL) de 10-6 exigé pour des liposomes a d’abord été évaluée en utilisant les spores de Bacillus Atropheus comme indicateur microbiologique de référence, en vue de sélectionner des conditions opératoires de procédé : C1 (70° C/150 bar/240 min), C1A (80° C/240 bar/30 min), C1B (80° C/150 bar/60 min), C1C (80° C/240 bar/60 min). Les conditions sélectionnées ont ensuite été utilisées pour la production de deux formulations de liposomes : F1 (HEPC/DC-CHOL/CHOL/DSPE-PEG2000 50,05/29,40/0,60/19,95 % m/m) et F2 (HSPC/CHOL/DSPE-PEG2000 65/30/5 % m/m). Les liposomes obtenus ont enfin fait l’objet d’une caractérisation physicochimique et microbiologique.   Résultats : les résultats ont montré l’atteinte du SAL requis pour les liposomes avec les conditions C1, C1B et C1C, lesquelles ont été utilisées pour les essais de production/stérilisation des deux formulations. Concernant les liposomes résultants, les résultats ont montré l’atteinte du SAL requis avec les 2 formulations pour toutes les 3 conditions. Par ailleurs des liposomes de caractéristiques appropriées pour une administration parentérale (taille <200 nm, PdI ≤ 0,3) ont été obtenus avec la formulation F2 pour toutes les 3 conditions. Conclusion : Le ScCO2 pourrait être utilisé pour la production et la stérilisation de liposomes dans un procédé en une seule étape

Alveolar echinococcosis is increasing in Southern Belgium: a report of the Belgian National Reference Laboratory for Echinococcosis (BNRLE) and clinical experience of ECHINO- Liege

peer reviewedIntroduction Alveolar echinococcosis (AE) is endemic in Southern Belgium where up to 50% of the red foxes might be infected and spread Echinococcus eggs in the environment. In humans, the primary target organ of AE is the liver, in which AE grows as a parasitic tumor and might later develop in other organs as a malignancy and be lethal. In response to the increasing number of AE cases, a multidisciplinary group (ECHINO-Liege) was created in CHU Liege to improve AE management and to discuss the AE cases. In addition, on the top of a retrospective AE registry, ECHINO-Liege is prospectively building a database (ECHINO-Base) and a biobank (ECHINO-Bank) of AE patients managed in CHU Liege, after EC approval and informed consent. Finally, since 2021, the Belgian National Reference Laboratory for Echinococcosis (BNRLE) is based in the department of Clinical Microbiology of CHU Liege. Aim The aim of this study was to report the actual epidemiological and clinical situation on AE in Belgium, using the BNRLE data and the clinical experience of ECHINO-Liege. Methods All Belgian clinical laboratories were asked to fill epidemiological forms on AE cases detected in 2021 and 2022. All cases confirmed by serology (immunoblot) and/or PCR and/or histology (proved cases) or without microbiological confirmation (probable and possible cases) were included. These cases were added to the retrospective series already published in 2018 and to the cases discussed during the regular meetings of ECHINO-Liege. Results AE was newly diagnosed and reported to BNRLE in 16 patients in the time-period of 2 years, added to the 36 patients previously registered (total: 52 patients, 29M/23F) (mean age: 60y, 19-89). Most patients were born and lived in Wallonia or the Brussels area. All cases but 2 are considered contracted in Belgium (1 in France and 1 in Luxembourg). 31 patients underwent liver resection and 1 liver transplantation. Conclusions AE appears to be spreading in Southern Belgium. The authorities should be aware of this public health issue. The radiologists and gastroenterologists should be informed of this diagnosis possibility in case of liver tumor. A national multicentric survey will be soon initiated as a collaboration between the different hospitals in the whole country

Belgian laboratory surveillance of human alveolar and cystic echinococcosis in 2021

peer reviewedBackground: Alveolar echinococcosis (AE) and cystic echinococcosis (CE), caused respectively by Echinococcus multilocularis and Echinococcus granulosus complex, are severe parasitic zoonoses which are potentially fatal for humans. While echinococcosis ranked among rare diseases in Belgium, an increasing incidence has been observed over the last two decades, in particular for AE. In order to describe the Belgian epidemiology, the National Reference Laboratory for echinococcosis (BNRLE) conducted a surveillance of AE and CE cases diagnosed in Belgium in 2021. Methods: All Belgian clinical laboratories were asked to fill an epidemiological form including AE and CE cases detected in 2021. All cases diagnosed by serology and/or PCR (confirmed cases) or without microbiological confirmation (probable and possible cases) were included. Results: In 2021, 17 new cases were detected throughout Belgium, including 7 AE and 10 CE. Three patients were not Belgian residents (2 AE from Luxembourg, 1 CE from the Netherlands). Among the 7 AE cases, sex ratio (male:female) was 3:4, the median age was 65 years, and the place of residence was restricted to Wallonia. CE cases were not restricted to a specific region. Unlike the alveolar form, CE occurred in a younger population (median age 43 years) and the sex ratio was 8:2. All CE cases were imported from endemic areas such as Turkey (4/10), Morocco (3/10), Bulgaria (1/10), Romania (1/10) and Middle Eastern countries (1/10). All cases were confirmed by serology and/or PCR except 4 CE cases for which the diagnostic methods were not specified. Conclusions: Because few laboratories perform diagnostic tests and few institutions are experienced in the clinical management, echinococcosis is probably underestimated in Belgium. Therefore, it is necessary to raise awareness among clinicians about the existence of these diseases in the country and to inform the population about the risk factors