Rationale: EGPA is a rare inflammatory disease associated with a high burden of disease and mortality. We performed a targeted literature review (TLR) to understand the current evidence on disease burden and the steps to diagnosis with EGPA.

Methods: A TLR was designed to search for real-world and randomized controlled studies in EGPA using MEDLINE and EMBASE for articles published before 11/23/20. Articles were screened according to PICOTS criteria (population, intervention, comparator, outcomes, timeframe, and study type). Numerical results are presented as range or simple average from the limited number of relevant studies identified.

Results: Of 1,023 references identified, 526 potentially relevant articles were eligible for full-text screening; of these, 33 priority articles were selected for an intensive review Globally, annual incidence is estimated as not above 2.3 cases per million, prevalence as 23 cases per million (US prevalence: 3.2-30.7 cases per million), and overall, 5-year mortality as 5–10%. More than 80% of patients with EGPA have comorbid asthma, sinusitis, or rhinitis. Manifestations occurring in >15% of patients include polyneuropathy, ocular involvement, cardio-cerebrovascular disease, and nasal polyposis. Between 6% and 30% of patients with EGPA overlap with hyper-eosinophilic syndromes, and approximately one-third of patients with EGPA are antineutrophilic cytoplasmic antibody (ANCA) positive. Non-specific presenting features lead to evaluation by multiple specialists and delayed diagnoses (average [range] age of diagnosis: 53 [14-77] years). Up to 71% of incident EGPA patients are hospitalized in the 5 years preceding diagnosis.

Conclusions: Patients with EGPA experience substantial disease burden with multiple comorbidities and challenging routes to diagnosis.