Dados do Trabalho

Título

FREQUENCY OF TYPICAL AND ATYPICAL FORMS OF OPTIC NEURITIS AT ONSET OF DEMYELINATING DISEASES OF THE CENTRAL NERVOUS SYSTEM

Objetivo

To describe the frequency and characteristics of typical and atypical forms of ON at disease presentation in a cohort of patients with DD-CNS.

Método

We selected patients with DD whose initial symptom was ON and classified as typical and atypical if it had or not the characteristics as shown by the Optic Neuritis Treatment Trial studies. We divided atypical ON into groups according to the presence of specific autoantibodies, the association with vaccines, previous infections or acute disseminated encephalomyelitis, or the presence of relapses.

Resultados

We analyzed 271 patients who presented ON at disease onset (101 of them typical and 170 atypical ON). Typical ON comprised idiopathic isolated ON in 13 (4.8%), and ON associated with multiple sclerosis in 88 (32.5%). Final diagnosis of patients with atypical ON included neuromyelitis optic spectrum disorders (NMOSD) in 73/170 (26.9%), with an overall percentage of 42.9%; recurring idiopathic ON in 26/170 (15.3%); MOG-related ON in 2/170 (1.2%); ADEM-related ON in 7/170 (4.1%); systemic autoimmune-related ON in 7/170 (4.1%); chronic relapsing inflammatory optic neuropathy in 2/170 (1.2%); parainfectious ON in 7/170 (4.1%); vaccine related ON in 14/170 (8.2%). Thirty-two (18.8%) patients had atypical ON of unknown etiology.

Conclusões

Multiple sclerosis related ON and NMOSD-ON at disease presentation are the most prevalent forms. Their careful characterization may help to establish the differential diagnosis between them.