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.