[A case of anti-Hu antibody- and anti-GluR epsilon2 antibody-positive paraneoplastic neurological syndrome presenting with limbic encephalitis and peripheral neuropathy].

We report a case of paraneoplastic neurological syndrome with anti-neuronal antibodies, namely anti-Hu and anti-GluR epsilon 2 antibodies in sera. A 72-year-old male had a transient history of eye movement disorder and sensory neuropathy, which improved spontaneously. Two years later, he was admitted to another hospital because of gait disturbance, numbness of the hands and an attack of unconsciousness with generalized convulsion. He was admitted to our hospital with prolonged consciousness disturbance and muscular weakness of all extremities. On admission his consciousness deteriorated slightly without neck stiffness. His cranial nervous system was normal except for incomplete abduction and elevation of both eyes. The patient had severe distal dominant weakness and atrophy in the muscles of all four limbs. Muscle tonus was decreased and hyporeflexia was noted in the four extremities. Plantar response was extensor. Neither sensory disturbance nor ataxia was observed. Cranial MRI showed T2-weighted high intensity lesions in the bilateral mesial temporal lobes, including the hippocampi. A nerve conduction study revealed motor-dominant peripheral neuropathy with prolonged latency; the amplitudes of compound muscle action potentials were severely reduced in all four limbs and those of sensory nerve action potentials were moderately reduced in the right upper and lower extremities. We also found a left hilar lymphadenopathy showing accumulation of FDG on PET, suggesting a possibility of malignancy. Anti-Hu and anti-GluR epsilon 2 antibodies were detected in sera but not in CSF. We diagnosed him with limbic encephalitis and peripheral neuropathy due to paraneoplastic neurological syndrome and treated him with two courses of intravenous immunoglobulin (IVIg) (400 mg/kg, 5 days). The consciousness disturbance, and prolonged distal latency revealed by motor nerve conduction studies improved slightly. Although the roles of anti-neuronal antibodies in paraneoplastic conditions remain unknown, we consider that IVIg may be worth using to treat cases with anti-Hu and anti-GluR epsilon 2 antibodies.

[Overlap case of Fisher syndrome and pharyngeal-cervical-brachial variant of Guillain-Barré syndrome].

A 29-year-old female developed diplopia, nasal voice and gait disturbance after an upper respiratory infection. On admission, she presented with bilateral external ophthalmoplegia, slight bilateral facial nerve palsy, dysarthria, dysphagia, cervical and brachial muscle weakness, ataxia and areflexia. She had serum anti-GT1a, anti-GQ1b and anti-galactocerebroside IgG antibodies. She was diagnosed with an overlap case of Fisher syndrome and pharyngeal-cervical-brachial variant of Guillain-Barré syndrome. Intravenous immunoglobulin therapy was effective for the ophthalmoplegia and ataxia, but did not improve the bilateral facial nerve palsy and brachial muscle weakness. The facial nerve palsy clearly worsened despite improvement in other symptoms, and therefore high-dose intravenous methylprednisolone therapy was added. The distinct response to treatment may be caused by different activity, production, clearance and reactivity to intravenous immunoglobulin of the autoantibodies. The present case suggests that treatment response and patterns of recovery differ according to the causative anti-ganglioside antibodies.