Multiple sclerosis: report on 200 cases from Iran.

Clinical findings of 200 patients in Iran with definite multiple sclerosis (MS) according to Poser et al.'s criteria and positive findings on magnetic resonance imaging (MRI) have been reviewed. The clinical course was relapsing-remitting (RR) for 88%, primary progressive (PP) for 7% and secondary progressive (SP) for 5% of cases. The mean age of onset was 27 +/- 7.4 years for the whole group and 37.1 +/- 8.8 years for PPMS. The gender ratio was 2.5:1 female:male. Involvement of the pyramidal system was the most common mode of presentation. Five per cent of patients had positive family history for the disease, 14% of patients had benign MS and 12% with disease duration longer than five years had an Expanded Disability Status Scale < or = 2. The optico-spinal form was not a common form of presentation in the group.