Groh et al.Orphanet Journalof Rare Diseases2023)18:100Orphanet Journal ofhttps:/dol.org/10.1186s13023-023-02696-4Rare DiseasesPOSITION STATEMENTOpen AccessFrench guidelines for the etiologicalworkup of eosinophilia and the managementof hypereosinophilic syndromesMatthieu Groh33Julien Rohmer36,Nicolas Etienne6,Wadih Abou Chahla36,Antoine Baudet736,Aurelie Chan Hew Wai836,Cecile Chenivesse9.1036,Irena Clisson Rusek11,36,Vincent Cottin1236Matthieu Decamp,Pascal De Groote,Fanny Delahousse,Nicolas DuployezStanislas Faguer,Frederic Gottrand1,Florent Huang20,Thierry Leblanc2,Antoine Magnan3Thierry Martin33 Geoffrey Mortuaire,Antoine Neel3,Luc Paris36,Arnaud Petit7.36Julien Rossigno Nicolas SchleinitzJuliette Soret-DulphyDelphine Staumont-SalleBenjamin Terrier3236,Louis Terriou,Jean-Francois Viallard36,Guillaume Lefevre3.34 andJean-Emmanuel Kahn 1.3536AbstractEosinophilic-related clinical manifestations are protean and the underlying conditions underpinning eosinophilia arehighly diverse.The etiological workup of unexplained eosinophilia/hypereosinophilia can be challenging,and canlead sometimes to extensive,inappropriate,costly and/or invasive investigations.To date,guidelines for the etiologi-cal workup and management of eosinophilia are mainly issued by hematologists,and thus mostly cover the scope ofclonal hypereosinophilic syndromes(HES).Here,thanks to an extensive literature review,and thanks to the joint workof a large panel of experts involving physicians from both adult and pediatric medicine and from various subspe-cialties (as well as a representative of a patients'association representative),we provide recommendations for boththe step-by step diagnostic workup of eosinophilia (whether unexplained or within specific contexts)as well as themanagement and follow-up of the full spectrum of eosinophilic disorders(including clonal,reactive,lymphocytic andidiopathic HES,as well as single-organ diseases).Didactic prescription summaries intended to facilitate the prescrip-tion of eosinophil-targeted drugs are also provided,as are practical diagnostic and therapeutic algorithms.Lastly,thisset of recommendations also includes a summary intended for general practitioners,as well as an overview of thetherapeutic patient education program set up by the French reference center for HES.Further updates will be manda-tory as new validated information emerges.Keywords Hypereosinophilia,Hypereosinophilic syndromes,Recommendation,ManagementCorrespondenceMatthieu Grohmgroh@hopital-foch.comFull list of author infor mation is available at the end of the articleBMCThe Author(s)2023.Open AccessThis artidle is licensed undera Creative Commons Attribution 40 Intemnational License,whichpermits use,sharing adaptation,distribution and repoducton in any medium orfomat as long as you give appropriatecedit to theofiginal author(s)and the source,provide a link to theCeative Commons licence,and indicate if changes wee made.The images orother third party materalin this artide ar
