Optic neuromyelitis syndrome in Brazilian patients

To report the clinical features and outcome of 24 Brazilian patients with optic neuromyelitis syndrome (ONM); discuss the underlying pathological events associated with the ONM syndrome; review the nosological situation of ONM in the group of inflammatory and demyelinating diseases of the central nervous system.

Patients with ONM treated at the Hospital da Lagoa, Rio de Janeiro were studied. Demographic, clinical, magnetic resonance imaging, cerebrospinal fluid, and pathological data were analysed.

The study consisted of 20 women, four men of whom 10 were white and 14 Afro-Brazilians. Clinical course was recurrent in 22 cases and monophasic in two. Neurological manifestations at inclusion were: sensory impairment (66%), bilateral (41.6%) or unilateral blindness (20.8%), paraplegia or quadriplegia (37.5%). The EDSS was moderate/severe in 70.8%. The underlying pathological events were respectively pulmonary tuberculosis and upper respiratory infection in the two monophasic cases; in the 22 recurrent ONM patients: pulmonary tuberculosis (3), neurocysticercosis (1), polyarteritis nodosa (1), antinuclear antibody and rheumatoid factor (1), antiphospholipid antibody primary syndrome (1), diabetes mellitus (1), hypothyroidism (1), and amenorrhea-galactorrhea (4). Normal cerebrospinal fluid was found in 52% and an inflammatory profile in 48%. Only four recurrent ONM white patients had brain and spinal cord magnetic resonance imaging and cerebrospinal fluid findings compatible with the diagnosis of multiple sclerosis. Large lesions were seen in 62% of spinal magnetic resonance images. Six of 12 recurrent ONM Afro-Brazilian died. There were no statistical differences in the demographic data of the two ethnic groups. Afro-Brazilians were significantly more severely impaired and had a higher mortality rate than the white patients.

These cases were classified as follows: two monophasic acute disseminated encephalomyelitis; one recurrent disseminated encephalomyelitis; three recurrent ONM associated with Hughes syndrome, autoantibodies and polyarteritis nodosa; six recurrent ONM with endocrinopathies; and finally, four multiple sclerosis cases. The remaining cases were not associated with any other condition. It would seem clear that ONM is a syndrome rather than a single disease.