Plasma exchange for steroid-refractory relapses in multiple sclerosis: an observational, MRI pilot study

Background: Numerous studies have shown that plasma exchange (PE) is effective as second-line treatment of severe exacerbations of multiple sclerosis (MS) or other idiopathic inflammatory demyelinating diseases of the central nervous system that are nonresponsive to steroid therapy.

Objective: The goal of this study was to analyze the effect of PE on clinically active radiologic lesions in steroid-refractory relapses of MS and idiopathic inflammatory demyelinating diseases of the central nervous system.

Methods: This was a prospective, observational pilot study in which the primary end point was the degree of radiologic resolution of active lesions after PE.

Results: A total of 15 patients were included (median age, 36.9 years [age range, 21-67 years]; 60% women). Five (33.3%) of the 15 patients had relapsing-remitting MS, 2 (13.3%) had clinically isolated syndrome that presented with transverse myelitis, 2 (13.3%) had recurrent myelitis, 1 (6.7%) had transverse myelitis, 1 (6.7%) had longitudinally extensive transverse myelitis, 1 (6.7%) had acute disseminated encephalomyelitis, 1 (6.7%) had Baló's concentric sclerosis, and 2 (13.3%) had neuromyelitis optica. Mean increase on the expanded disability status scale scores due to relapses was 4.8 (2.53). After PE, 93.3% showed a marked to moderate clinical improvement, and 46.7% recovered their baseline expanded disability status scale score 3 months post-PE. On the post-PE MRI, 60% showed radiologic resolution (80% mass-effect lesions, 83.3% new-onset disease, and 100% neuromyelitis optica), 20% had partial resolution, and 20% no resolution. A significant relationship was not obtained between degree of resolution of radiologic lesions and the variables: clinical response to PE, new-onset disease, mass-effect lesions, number of PE sessions, and early initiation of PE.

Conclusion: A marked to moderate clinical improvement post-PE accompanied by a lack of radiologic resolution of the active lesion is not indicative of poor prognosis.