Association of rhinocerebral mucormycosis and granulomatosis with polyangiitis (Wegener's granulomatosis).

Rhinocerebral mucormycosis is a rare but life-threatening fungal infection that predominantly affects immunocompromised individuals. We describe the case of a man in his mid-60s with a history of rheumatoid arthritis, diabetes mellitus and chronic kidney disease who developed invasive mucormycosis in the setting of suspected granulomatosis with polyangiitis (GPA). The patient presented with acute right-sided visual loss, proptosis and ophthalmoplegia. Imaging revealed paranasal sinus involvement and optic nerve compression. The diagnosis was confirmed histopathologically following endoscopic sinus surgery. The clinical course was complicated by altered mental status and respiratory compromise, necessitating intensive care admission. Treatment included systemic antifungal therapy with liposomal amphotericin B and posaconazole, alongside cautious modulation of immunosuppressive therapy under multidisciplinary supervision. This case underscores the diagnostic and therapeutic challenges of coexisting GPA and mucormycosis. It highlights the importance of early recognition, prompt surgical intervention and a coordinated, multidisciplinary approach to optimise outcomes in patients with overlapping autoimmune and opportunistic infectious conditions.