TY - JOUR T1 - Childhood-onset severe hypereosinophilic asthma: efficacy of benralizumab JF - ERJ Open Research JO - erjor DO - 10.1183/23120541.00339-2020 VL - 6 IS - 4 SP - 00339-2020 AU - Jocelyne Just AU - Melisande Bourgoin AU - Flore Amat AU - Nathalie Cottel AU - Nathalie Lambert AU - Stephanie Wanin Y1 - 2020/10/01 UR - http://openres.ersjournals.com/content/6/4/00339-2020.abstract N2 - Hypereosinophilic syndrome (HES) is a group of rare chronic disorders that are defined by an absolute blood eosinophil count (BEC) of at least 1.500×109 cells·L−1 on at least two occasions [1] with absence of secondary causes of eosinophilia (including parasitic infections, malignancy as myeloproliferative variants) and end-organ eosinophilic infiltration with associated damage [2]. In 2006, a working group modified the definition of HES to include other previously distinct disease entities associated with eosinophilia, such as eosinophilic granulomatosis with polyangiitis (EGPA, formerly known as Churg–Strauss syndrome) and chronic eosinophilic pneumonia [3]. EGPA typically occurs in middle-aged adults with asthma, and childhood-onset is rare with a prevalence of 10–13 patients per million people [4, 5]. We report here a series of six children with childhood-onset asthma with oral corticosteroid (OCS) dependence associated with hypereosinophilic asthma with a long-term follow-up and the marked efficacy of benralizumab. The study was declared to the French Data Protection Authority (CNIL) according to the reference methodology MR004. All of the included patients or their parents received an information note and were given the opportunity to oppose the use of their personal data, but no refusals were received.Severe hypereosinophilic asthma in children is extremely rare. This letter adds to the existing literature by providing long-term follow-up, and is the first report of the marked efficacy of benralizumab after failure of other biologic treatments. https://bit.ly/2G7Tc2k ER -