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