Granulomatosis with polyangiitis presenting with predominant neuro-otological involvement in an adolescent male: A diagnostic challenge - A case report.

Granulomatosis with polyangiitis (GPA) is a rare Antineutrophil Cytoplasmic Antibodies (ANCA)-associated vasculitis that typically affects the upper and lower respiratory tract and kidneys. In adolescents, atypical presentations with predominant neuro-otological features may delay diagnosis. We report a 15-year-old boy who presented with progressive bilateral sensorineural hearing loss, facial nerve palsy, multiple lower cranial nerve deficits, dysphagia, and hoarseness, initially suggestive of chronic meningitis. Magnetic resonance imaging showed pachymeningeal enhancement with skull-base involvement. There was no renal or classical sinonasal involvement. Pulmonary infiltrates were initially attributed to aspiration pneumonia, and an infectious etiology was suspected. Prolonged antimicrobial therapy, however, did not result in sustained improvement. Lung biopsy demonstrated necrotizing granulomatous inflammation, and PR3-ANCA positivity confirmed GPA. Immunosuppressive therapy led to marked clinical improvement. Predominant neuro-otological involvement with misleading pulmonary findings can pose a significant diagnostic challenge in adolescent GPA.