Etiologies and Outcomes of Granulomatosis With Polyangiitis-Associated Optic Neuropathy: A Case Series and Review of the Literature.

Background: Granulomatosis with polyangiitis (GPA), formerly known as Wegener granulomatosis, is a rare autoimmune disease characterized by inflammation of small- to medium-sized blood vessels (vasculitis). We described the 3 causes of GPA-associated optic neuropathy (compressive, inflammatory, or ischemic) and analyzed initial and final visual acuities (VAs) in each group, which could potentially help prognosticate visual outcomes depending on the etiology of optic neuropathy.

Methods: This was a retrospective chart review of patients who were diagnosed with GPA-associated optic neuropathy and were seen in the Department of Ophthalmology at Mayo Clinic in Rochester, Minnesota. Only patients who met the 2022 American College of Rheumatology/European Alliance of Associations for Rheumatology GPA classification criteria were included.

Results: A total of 12 patients with GPA-associated optic neuropathy were identified. The etiology of the optic neuropathy was compressive in 6 patients, inflammatory in 4 patients, and ischemic in 3 patients. One patient had compressive optic neuropathy initially, then presented with GPA-related optic neuritis years later. Four patients in the compressive optic neuropathy group had orbital masses requiring orbitotomy for debulking, and the remaining 2 patients had compression from pachymeningitis. Average logarithm of the minimum angle of resolution (logMAR) VA at optic neuropathy onset was 1.50, 1.50, and 0.67 (Snellen equivalent 20/600, 20/600, and 20/100, respectively). At the last follow-up, average logMAR VA was 0.91, 1.73, and 1.10 (Snellen equivalent 20/160, 20/1,000, and 20/250, respectively) for each group.

Conclusion: Visual outcomes were variable, with compressive and inflammatory optic neuropathies showing improvement in 4 eyes and worsening in 3 eyes in total. Patients with ischemic optic neuropathy from GPA were either stable or worsened over the course of the disease.