Diagnostic and Therapeutic Challenges in Limited GPA With Nasal Synechiae: A Case Report and Literature Review

Usually linked with anti-neutrophil cytoplasmic antibodies (ANCA), granulomatosis with polyangiitis (GPA) is an uncommon systemic necrotizing vasculitis. Although GPA sometimes shows multiorgan involvement, the confined phenotype-mostly affecting the upper respiratory tract-can provide major diagnostic and therapeutic difficulties. Though nonsystemic, limited GPA might resemble chronic rhinosinusitis and is at risk for progression or consequences.

Following COVID-19 immunization and past COVID-19 infection, we describe a case of a 23 year-old girl presenting with persistent nasal obstruction, headache, severe facial pain, crustation, nose bleeding, and anosmia for 1.5 years. Examination revealed bilateral nasal ulceration and crusting; evaluation also indicated mucosal thickening and positive c-ANCA with high proteinase 3 titers. Without granulomatous characteristics, histopathology revealed persistent inflammation and inflammatory nasal polyps. The patient was first managed with methotrexate; therapy was upgraded to rituximab (RTX) due to ongoing symptoms. After RTX induction, the patient achieved clinical remission, with resolution of nasal symptoms and normalization of inflammatory markers. She stayed in remission at the follow-up.

This case highlights the diagnostic complexity and therapeutic challenges associated with limited GPA, particularly when ear, nose, and throat symptoms predominate without systemic involvement. Key to reaching remission is early rheumatologic referral, interdisciplinary treatment, and rapid escalation to biologic therapy. RTX is a good and well-tolerated choice in refractory restricted GPA; yet more studies are warranted.