Late onset multiple sclerosis

Late onset multiple sclerosis (LOMS) is an unusual entity, poorly characterised and difficult to diagnose.

To study a series of patients with LOMS (presentation of the first symptom of disease after the age of 50 years).

In this retrospective study we review demographic characteristics, first onset symptom, diagnostic delay, disability at the time of diagnosis (EDSS), disease course and findings in SCF, VEP and MRI studies.

We included 18 patients (12 F and 6M) with LOMS (4.8% of the total). The most frequent first symptoms were motors deficits (33%), multisystem deficits (33%) and cerebellum disorder (16%). Clinical course (all the cases with a minimal follow-up of 5 years after the diagnosis): primary progressive-MS (62%), secondary progressive-MS (22%), relapsing-remitting-MS (16%). The initial EDSS score was higher than 4 points in one third of patients and diagnosis delay was over 5 years in two thirds of cases. The cerebral MRI study was abnormal and compatible with MS in all patients and fulfilled the Barkhof criteria in 12 (67% of cases). Oligoclonal IgG bands were positive in the 64% of patients in the CSF study and VEP were abnormal in the 73%. The most frequent wrong diagnoses were cerebrovascular disorders and spondyloarthritic cervical myelopathy.

LOMS course is often primary, progressive and motor and multisystem symptoms are the most frequent. The diagnosis is usually delayed and when it is made patients have a high disability score. The findings of cerebral and spinal MRI, CSF and VEP studies are of high diagnostic yield. Cerebrovascular disorders and spondyloarthritic cervical myelopathy are the most important entities in the differential diagnosis of LOMS.