[A case of neuralgic amyotrophy with antiganglioside antibody]

A 54-year-old-man experienced pain from his left shoulder to his left arm and had difficulty in lifting his arm after a febrile episode. Three weeks after the onset, he was admitted to our hospital. Neurological examination demonstrated weakness and atrophy of the left deltoid muscle. Deep tendon reflexes were normal and no pathological reflexes were elicited. CSF total protein was slightly increased. The occurrence rate of F-waves was decreased in the left upper limb. Magnetic resonance imaging (MRI) study of the cervical cord and brachial plexus with and without Gadolinium infusion showed no abnormalities. Serological study showed that IgM anticytomegalovirus antibody was positive, and that serum IgM anti-GalNAc-GD1a antibody and IgM anti-GM2 antibody were positive. Symptoms were improved after treatment with mecobalamin, 1.5mg/day. This case was considered neuralgic amyotrophy after cytomegalovirus infection. The antiganglioside antibodies may play some role in its pathogenesis.