TRANSITIONAL PROGRESSIVE MULTIPLE-SCLEROSIS - A CLINICAL AND IMAGING STUDY

Objective - To study the prevalence and the natural course of transiti onal progressive multiple sclerosis (TPMS). This clinical form is defi ned by a progressive course beginning many years after an isolated bou t. Methods - 214 consecutive outpatients with definite or probable mul tiple sclerosis were studied. The prevalence of TPMS was established. Patients with TPMS were compared with patients with other progressive forms of multiple sclerosis according to the clinical course. A prospe ctive one year follow up study was performed in a subgroup of patients to compare progression of the disease using clinical indices and MRI. Results - In this clinical population of 214 outpatients with multipl e sclerosis, 55 had secondary progressive multiple sclerosis (SPMS), 3 8 primary progressive multiple sclerosis (PPMS), and 12 TPMS. Retrospe ctive analysis of the clinical data of these patients shows that TPMS is very similar to SPMS at the beginning of the disease (age at onset, time before progression, clinical symptoms at onset, progression inde x). In addition a cohort patients was prospectively followed clinicall y and by MRI for one year. Conclusions - The results did not show any significant differences between the three forms during this follow up. However, all data showed a concordant trend suggesting that at this p rogressive stage, TPMS is closer to PPMS in terms of progression of di sability and new MRI lesions.