Tohoku J. Exp. Med., 2011, 223(3)

Therapeutic Efficacy of Interferon β-1b in Japanese Patients with Optic-Spinal Multiple Sclerosis

YUKO SHIMIZU,¹ KAZUO FUJIHARA,² SACHIKO KUBO,¹ TOSHIYUKI TAKAHASHI,³ TATSURO MISU,² ICHIRO NAKASHIMA,² KAZUMASA YOKOYAMA,⁴ YASUTO ITOYAMA⁵ and SHINICHIRO UCHIYAMA¹

¹Department of Neurology, Tokyo Women's Medical University School of Medicine, Tokyo, Japan
²Department of Neurology, Tohoku University School of Medicine, Sendai, Japan
³Department of Neurology, National Yonezawa Hospital, Yonezawa, Japan
⁴Department of Neurology, Juntendo University School of Medicine, Tokyo, Japan
⁵National Center Hospital, National Center of Neurology and Psychiatry, Tokyo, Japan

Optic neuritis and myelitis are manifestations in both multiple sclerosis (MS) and neuromyelitis optica (NMO). But unlike MS, NMO is characterized by severe optic neuritis, longitudinally extensive and transverse myelitis, and the presence of aquaporin-4 antibody. Since patients with optic neuritis and myelitis have often been diagnosed with “optic-spinal MS (OSMS)” in Asia, it was obscure whether “OSMS” is synonymous with NMO or includes both NMO and MS. Interferon β (IFNβ)-1a and -1b are used as the first-line disease-modifying therapy for MS. However, some neurologists have been reluctant to use IFNβ to treat patients with optic-spinal symptoms, because IFNβ therapy is not efficacious in NMO. To evaluate the therapeutic effect of IFNβ in patients with “genuine” OSMS, we retrospectively evaluated Japanese MS patients who fulfilled the following six criteria: 1) Relapsing-remitting MS with optic-spinal presentation alone (no brain symptoms), 2) With or without asymptomatic brain MRI lesions, 3) Oligoclonal IgG band-positive, 4) aquaporin-4 antibody seronegativity, 5) No myelitis extending longitudinally over ≥ 3 vertebral segments, and 6) Duration of IFNβ-1b therapy ≥ 2 years. Among 157 patients with MS, six (four women and two men, age 43.8 ± 8.5 years old) met all the criteria. Their Expanded Disability Status Scale scores were lowered (4.1 ± 2.4 → 3.1 ± 2.8) (P = 0.033) and annualized relapse rate was decreased (0.59 ± 0.34 → 0.13 ± 0.15) (P = 0.027) after IFNβ-1b therapy. These results suggest that IFNβ is therapeutically effective in inhibiting functional worsening and reducing relapse rate in “genuine” OSMS.

keywords —— optic-spinal multiple sclerosis; interferon-beta therapy; neuromyelitis optica; aquaporin-4 antibody; oligoclonal IgG band

© 2011 Tohoku University Medical Press

===============================

Tohoku J. Exp. Med., 2011, 223, 211-214

Correspondence: Yuko Shimizu, M.D., Department of Neurology, Tokyo Women's Medical University School of Medicine, 8-1 Kawada-cho, Shinjuku-ku, Tokyo 162-8666, Japan.

e-mail: yshimizu@nij.twmu.ac.jp