Hoarseness as an Early Manifestation of Granulomatosis with Polyangiitis: A Case Highlighting Diagnostic Challenges.

Granulomatosis with polyangiitis (GPA) is a systemic necrotizing small-vessel vasculitis that commonly involves the upper and lower respiratory tracts and kidneys and is potentially life-threatening. Early manifestations may be subtle and misleading, resulting in delayed diagnosis and treatment. Laryngeal involvement, particularly presenting as isolated dysphonia, remains an underrecognized and easily overlooked feature. We report a 77-year-old man with a history of lymphoma and previous lung cancer in remission who presented with six weeks of progressive hoarseness, shortness of breath, profound weight loss, and constitutional symptoms. On presentation, he was found to have multifocal pulmonary opacities, acute kidney injury with active urinary sediment, and systemic inflammation. The constellation of symptoms and his complex medical history created a diagnostic challenge. A unifying diagnosis emerged only after serologic testing revealed positive cytoplasmic anti-neutrophil cytoplasmic antibodies (C-ANCA) and anti-elevated proteinase-3 (PR3) antibodies. Renal biopsy confirmed pauci-immune crescentic glomerulonephritis consistent with GPA. Prompt initiation of pulse-dose corticosteroids and rituximab resulted in rapid clinical improvement. This case underscores dysphonia, which may represent an early and critical clue to airway involvement, preceding fulminant multisystem disease. Recognition of this presentation is essential, as diagnostic delay may lead to irreversible organ damage, whereas timely immunosuppressive therapy can be rapidly life-saving and organ-preserving.