Clinical course of optic neuritis in patients with relapsing neuromyelitis optica.

OBJECTIVE To describe the clinical characteristics, course, and prognosis of optic neuritis in recurrent neuromyelitis optica. METHODS We analyzed 60 patients diagnosed using 1999 Mayo Clinic criteria who were seen between 1985 and 2004 at Hospital da Lagoa (Rio de Janeiro, Brazil). RESULTS Optic neuritis was the initial feature in 53.3% of patients, most with unilateral disease. Recurrent optic neuritis before myelitis occurred in 18.3%. The visual impairment was severe at nadir of the visual index event in 78.3%, with a high remission rate. In the median disease duration of 8 years (range, 0.5-30 years), 380 relapses (118 optic neuritis, 223 myelitis, 39 optic neuritis and myelitis) occurred. At the last follow-up, 53.3% of patients had bilateral visual impairment and 63.3% were blind in at least 1 eye. A high mortality rate (23.3%) was due to cervical myelitis. Mortality rates were significantly higher among Afro Brazilian patients (58.3%). CONCLUSIONS Optic neuritis in patients with recurrent neuromyelitis optica has a severe and acute onset, with predominantly unilateral lesions followed by improvement of clinical symptoms. In the long-term, the disease leads to severe bilateral visual impairment. Mortality rates are higher among patients of Afro Brazilian descent.