PO:35:226 | Red flags raising suspicion of Eosinophilic Granulomatosis with Polyangiitis (EGPA): results from the European EGPAware Delphi study

Gabriele Brembilla¹, Bernhard Hellmich^2|3, Apostolos Bossios^4|5, Chistian Domingo-Ribas^6|7, Giacomo Emmi⁸, Cristina Ponte^9|10, Maria Roser Solans-Laque¹¹, Íñigo Jesus Rúa-Figueroa¹², Augusto Vaglio¹³, Dimitrios Vassilopoulos¹⁴, Konstantina Kallinikou¹⁵, Benjamin Terrier¹⁶ | ¹GSK Verona, Italy; ²Medius Klinik Kirchheim Kirchheim unter Teck Germany; ³Teaching Hospital of the University of Tübingen Tübingen Germany; ⁴Karolinska University Hospital Stockholm, Sweden; ⁵Karolinska Institutet Solna, Sweden; ⁶Parc Taulí University Hospital. Parc Taulí Research and Innovation Institute I3PT-CERCA Barcelona Spain; ⁷Department of Medicine, Universitat Autònoma de Barcelona ^UAB Barcelona Spain; ⁸University of Trieste, UNITS, Trieste, Italy; ⁹Santa Maria Hospital Lisbon, Portugal; ¹⁰Lisbon Academic Medical Center Lisbon, Portugal; ¹¹Vall d'Hebron University Hospital Barcelona Spain; ¹²Gran Canaria Doctor Negrín Hospital Las Palmas de Gran Canaria Spain; ¹³University of Florence Florence, Italy; ¹⁴National and Kapodistrian University of Athens School of Medicine Athens, Greece; ¹⁵GSK Athens, Greece; ¹⁶Cochin Hospital Paris, France

Purpose of the work. Diagnosing EGPA is challenging due to its rarity, multisystem involvement, and unspecific symptoms like asthma, often delaying diagnosis and treatment, increasing the risk of organ damage. EGPAware is the first multidisciplinary Delphi study to seek consensus among European experts to develop a checklist of red flags for early EGPA recognition.

Methods. EGPAware is led by a panel of European EGPA experts (4 rheumatologists, 2 internal medicine specialists, 2 pulmonologists, a nephrologist and an immunologist). The Delphi questionnaire covered panellists’ profile, current clinical management and red flags for EGPA suspicion in adult patients with asthma and blood eosinophilia (>1000 cells/mcL or >500 cells/mcL, if previously treated with any medication that may have altered the blood eosinophil count). The committee defined profiling questions and proposed red flags. Consensus was determined with =/>70% agreement. In round two, statements with <70% consensus were revisited, and the 10 most pertinent signs based on clinical relevance and frequency of observation were ranked (based on panellists’ experience). Data was analysed with descriptive statistics.

Results. 53 EGPA-treating physicians from 15 countries completed the two Delphi survey rounds. The panel included rheumatologists (35.8%), pulmonologists (30.2%), internal medicine physicians (11.3%), immunologists (9.4%), nephrologists (5.7%), allergologists (5.7%) and a dermatologist (1.9%). Half had over 15 years of experience managing EGPA, all using a multidisciplinary approach. Consensus was reached on 25 out of 47 red flags for EGPA suspicion, including mononeuritis multiplex (98.1%), lung infiltrate/nodule(s) (92.5%), alveolar haemorrhage (79.2%), retinal vasculitis (73.6%) and episcleritis/scleritis (71.7%). General signs like constitutional symptoms (weight loss, fever, fatigue etc.) (79.2%) and digital ischaemia (73.6%) also achieved consensus. Alveolar haemorrhage and digital ischemia reached consensus despite their rarity, while frequent non-specific findings like proteinuria did not. Proteinuria (67.9%) and elevated creatinine with or without active urine sediment (66.0%) failed consensus despite glomerulonephritis achieving high consensus (89.4%). Cardiomegaly (60.4%), chronic diarrhoea (18.9%) and venous thrombosis (54.7%) also failed to reach consensus. However, in the context of asthma and blood eosinophilia, these signs could warn of other conditions. The most important red flags ranked by clinical relevance included mononeuritis multiplex, lung infiltrates/nodules, vasculitis on biopsy and MPO-ANCA positivity (Table 1), while the most frequently observed red flags were lung infiltrates/nodules, nasal polyposis and mononeuritis multiplex (combined prioritisation in Figure 1).

Conclusions. EGPAware is the first European study to provide a checklist of red flags, developed with inputs from a multidisciplinary panel, for identifying potential EGPA cases, improving referral and treatment timelines. The study reveals variability in how physicians prioritise red flags, emphasising the need for unified training and a multidisciplinary approach to EGPA management.