Pathogenic Mechanisms Associated With Different Clinical Courses of Multiple Sclerosis

In the majority of patients multiple sclerosis starts with a relapsing remitting disease (RRMS), which may at later times transform into secondary progressive disease (SPMS). In a minority of patients the relapsing remitting disease is skipped and the patients show progression from the onset (primary progressive MS, PPMS). Evidence obtained so far indicate major differences between RRMS and progressive MS, but no essential differences between SPMS and PPMS, with the exception of a lower incidence in the global load of focal white matter lesions and in particular in the presence of classical active plaques. We suggest that in MS patients two types of inflammation occur, which develop in parallel but partially…