Epidemiological and clinical characteristics of patients in the alveolar echinococcosis registry, France, 1982 to 2021.

BACKGROUNDEchinococcus multilocularis is a parasite causing alveolar echinococcosis (AE), a severe disease affecting primarily the liver. Surveillance of this non-notifiable disease in France is performed by the National Reference Center for Echinococcoses (NRC-E).AIMWe aimed to analyse changes in epidemiological, clinical and survival data of patients with AE over time.METHODSWe described and analysed data from 906 AE patients reported to the NRC-E over three periods: 1982-1999, 2000-2010 and 2011-2021, using regression methods and survival analysis methods.RESULTSAt diagnosis, the median age of the patients was 60.0 years, most (770; 85.0%) resided in an endemic region and 483 (53.3%) in a rural area. The percentage of asymptomatic patients increased significantly from 19.1% (48/251) in 1982-1999 to 56.2% (209/372) in 2011-2021 (p < 0.001). The number of patients with weakened immune systems increased significantly in 2000-2021 (p < 0.001). Most (761/836; 91.0%) patients were treated with antiparasitic drugs and 402 (44.4%) underwent surgery. The number of surgical interventions decreased significantly during the study period (p = 0.007). Palliative surgery decreased, curative hepatic resection became more commonly performed (p < 0.001). Multivariate analysis showed a lower risk of death in the first 10-year follow-up in patients diagnosed after 2000 and those receiving benzimidazoles (sub-distribution hazard ratio (SHR) = 0.43; 95% confidence interval (CI): 0.28-0.66; p < 0.001).CONCLUSIONInternational recommendations for treating all patients with benzimidazoles and favouring curative hepatic resection, whenever possible, were generally followed and associated with better survival. We recommend national and European-wide registries to ensure effective surveillance of AE.