Granulomatosis with polyangiitis complicated with refractory optic neuritis and maxillary osteomyelitis

We report a case of a 61-year-old man with granulomatosis with polyangiitis (GPA) complicated with refractory optic neuritis and maxillary osteomyelitis. He had been treated with prednisolone (PSL) as cryptogenic organizing pneumonia in the respiratory department for 2 years. Afterward, he complained tenderness of paranasal sinuses and rapidly progressive visual loss of the left eye. Although both MPO-ANCA and PR3-ANCA were negative, he was diagnosed as GPA based on the American College of Rheumatology 1990 criteria. Ophthalmologic and oral examination revealed left optic neuritis and destructive maxillary bone. Magnetic resonance imaging (MRI) showed the optic neuritis and inflammation around the optic nerve. This finding suggested that the direct spread of inflammation from paranasal sinuses caused the optic neuritis. In a short time, increasing a dose of PSL and administration of intravenous cyclophosphamide were initiated. Antibiotics were also administered to treat sinusitis. Although his visual acuity of the left eye deteriorated to no light perception temporarily, it finally improved after treatment and findings of MRI were also improved. In contrast, destruction of maxilla bone had been progressing. This is a rare case of GPA complicated with optic neuritis due to sinusitis and maxillary osteomyelitis.