Eosinophilic Granulomatosis with Polyangiitis
Overview
Plain-Language Overview
Eosinophilic Granulomatosis with Polyangiitis is a rare disease that affects the blood vessels and causes inflammation throughout the body. It mainly involves the lungs, skin, and nerves, leading to symptoms like asthma, rash, and numbness or weakness. The condition is marked by an increase in a type of white blood cell called eosinophils, which can damage tissues. This disease can cause serious problems by blocking blood flow or damaging organs. It often starts with asthma and allergies before progressing to more severe symptoms. Early recognition is important because it can affect many parts of the body and requires medical evaluation.
Clinical Definition
Eosinophilic Granulomatosis with Polyangiitis (EGPA) is a systemic necrotizing vasculitis characterized by eosinophil-rich granulomatous inflammation and vasculitis affecting small- to medium-sized vessels. It is associated with hypereosinophilia and often presents in patients with a history of adult-onset asthma and allergic rhinitis. The pathogenesis involves immune dysregulation leading to eosinophil activation and vascular inflammation, causing tissue damage and ischemia. EGPA is classified among the ANCA-associated vasculitides, with about 40% of patients testing positive for p-ANCA (MPO-ANCA). Major clinical features include pulmonary infiltrates, peripheral neuropathy, and skin lesions. The disease progresses through phases: prodromal allergic, eosinophilic, and vasculitic, reflecting its complex immunopathology and multisystem involvement.