A Prominent Elevation of Glial Fibrillary Acidic Protein in the Cerebrospinal Fluid during Relapse in Neuromyelitis Optica

A Prominent Elevation of Glial Fibrillary Acidic Protein in the Cerebrospinal Fluid during Relapse in Neuromyelitis Optica

RINA TAKANO,¹ TATSURO MISU,^1,2 TOSHIYUKI TAKAHASHI,³ MASAHIRO IZUMIYAMA,⁴ KAZUO FUJIHARA^1,2 and YASUTO ITOYAMA¹

¹Department of Neurology, Tohoku University Graduate School of Medicine, Sendai, Japan
²Department of Multiple Sclerosis Therapeutics, Tohoku University Graduate School of Medicine, Sendai, Japan
³Department of Neurology, Yonezawa National Hospital, Yonezawa, Japan
⁴Department of Neurology, Sendai Nakae Hospital, Sendai, Japan

Neuromyelitis optica (NMO) is a neurologic disease characterized by severe optic neuritis, longitudinally extended, transverse myelitis and serum aquaporin-4 (AQP4) antibody. Our recent neuropathological study revealed the extensive loss of AQP4 and glial fibrillary acidic protein (GFAP), an astrocyte-specific protein, in NMO lesions, but not in MS lesions, suggesting that severe astrocytic damage or dysfunction may be related to the pathogenesis of NMO. Here we report a patient of NMO, in which the cerebrospinal fluid (CSF) levels of GFAP were measured both during relapse of myelitis and after high-dose intravenous methylprednisolone (HIMP). The patient was a 34-year old woman with two previous episodes of optic neuritis. She developed myelitis longitudinally extending from C3 to T12 with contrast enhancement, and was AQP4 antibody-positive. In the acute phase, the GFAP level in the cerebrospinal fluid (CSF) was prominently elevated (18,966.7 ng/ml) as compared with controls (0.6 ± 0.33 ng/ml). However, following HIMP, the clinical and MRI findings improved, and the CSF-GFAP level was near-normal (2.1 ng/ml). The CSF of myelin basic protein was also elevated in relapse (1,016.0 pg/ml), and became lower but still remained high (158.7 pg/ml) after HIMP compared with controls (3.36 ± 3.83 pg/ml). The prominent elevation of the CSF-GFAP level in relapse of NMO, followed by its sharp decline after therapy, suggests severe astrocytic damage with a temporal profile distinct from that of the demyelinating process in NMO. CSF-GFAP may be useful as a biomarker of NMO.

keywords —— glial fibrillary acidic protein (GFAP); neuromyelitis optica; cerebrospinal fluid; myelin basic protein; relapse.

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Tohoku J. Exp. Med., 2008, 215, 55-59

Correspondence: Kazuo Fujihara, M.D., Department of Multiple Sclerosis Therapeutics, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai 980-8574, Japan.

e-mail: fujikazu@em.neurol.med.tohoku.ac.jp