Clinical features of familial multiple sclerosis in Spain

Introduction. Multiple sclerosis (MS) is a demyelinating and inflammatory disease of the central nervous system (CNS) with a clear proved genetic susceptibility. The real frequency and clinical features of familial MS is although not well established in Spain. Objective. We studied the clinical and CSF features of familial MS (FMS) patients in comparison with the rest of our patients. Patients and methods. We reviewed 308 definite MS patients looking for patients with other familial members with MS. We analyzed clinical characteristics (age, age at onset, sex, evolution time, evolution course, symptoms at onset, disability measured by EDSS scale) and IgG synthesis measured by Tibbling-link index. Results. We found 23 patients (10 men and 13 women) in 18 independent families with at least other family member diagnosed of definite MS (7.47% of our total MS population). Age and age at onset were no different from non FMS cases. The clinical course was relapsing-remitting in 21 out of 23 FMS cases and secondary progressive in two. No primary progressive cases were found among FMS. At onset the symptom most frequently found in FMS was optic neuritis. Mean EDSS score was lower in FMS cases in comparison with the rest of cases. Link index was increase in 93.7% of patients with FMS. Conclusion. In comparison with non familiar forms FMS patients in Spain, present more often remitting courses, are less disabled, optical neuritis is more frequently seen as onset symptom and IgG synthesis is more often increased.