Catastrophic subarachnoid hemorrhage in eosinophilic granulomatosis with polyangiitis without asthma

Eosinophilic granulomatosis with polyangiitis (EGPA) is characterized by eosinophilic vasculitis. Patients rarely present without asthma. Cases developing subarachnoid hemorrhage from central nervous system vasculitis are rarely reported. We report a 48-year-old woman with rapidly evolving and progressive multi-system eosinophilic vasculitis in the absence of asthma. Tissue eosinophilia was apparent in a breast lump biopsy. Prior otitis media and prominent lymphoid tissue in the postnasal spaces hinted at otolaryngological disease. She had rapid disease progression with mononeuritis multiplex and eventually succumbed to complications of intracranial hemorrhage secondary to central nervous system vasculitis. This case demonstrates the diagnostic dilemma and treatment considerations in EGPA without asthma. It also raises the question if a reliable biomarker can aid diagnosis in atypical presentations of disease.

Eosinophilic granulomatosis with polyangiitis (Churg-Strauss): state of the art

Eosinophilic granulomatosis with polyangiitis (Churg-Strauss, EGPA) is a systemic small-vessel vasculitis associated with asthma and eosinophilia. Histology of EGPA shows tissue eosinophilia, necrotizing vasculitis, and eosinophil-rich granulomatous inflammation. EGPA commonly presents with upper airway tract and lung involvement, peripheral neuropathy, cardiac and skin lesions. Antineutrophil cytoplasmic antibodies (ANCA) are positive in ~40% of the cases and more often in patients with clinical manifestations due to small-vessel vasculitis. The pathogenesis of EGPA is multifactorial: the disease can be triggered by exposure to allergens or drugs, but a genetic background has also been recognized, particularly an association with HLA-DRB4. Th2 responses are prominent, with up-regulation of IL-4, IL-13, and IL-5; however, Th1 and Th17 responses are not negligible. Eosinophils are activated, have a prolonged lifespan and probably cause tissue damage by releasing their granule proteins; their tissue recruitment can be regulated by chemokines such as eotaxin-3 and CCL17. Humoral immunity is also dysregulated, as demonstrated by prominent IgG4 and IgE responses. EGPA promptly responds to glucocorticoid therapy, although combinations of glucocorticoids and immunosuppressants (e.g., cyclophosphamide, azathioprine) are eventually required in most cases. Newer therapeutic options include the anti-IL5 antibody mepolizumab, whose efficacy has been described in small clinical trials, and the B-cell-depleting agent rituximab, reported in several case series.