[A case of "neuralgic amyotrophy" with elevated serum antibody titer against Borrelia burgdorferi].

A 39-year-old man experienced an abrupt onset of right back pain. The pain improved spontaneously, but weakness of the right upper extremity developed. The weakness deteriorated during the next month, and he was admitted to our hospital. Neurological examination disclosed impairment of superficial sensation in his right upper extremity. Blood examination showed no abnormal data. The cerebrospinal fluid was normal. Neuroradiological findings were also negative. Electrophysiological examinations were normal except for needle electromyographic findings of the right upper extremity, which showed neurogenic patterns of moderate degree. Those findings suggest neuralgic amyotrophy. However, examining the serum sample significantly elevated levels of antibody titers against Borrelia burgdorferi were observed, and we suspected that his illness was Lyme disease. He recalled, however, no arthropod bite. Neuralgic amyotrophy is a syndrome which takes a characteristic clinical course. It includes some heterogeneous disorders. On the other hand, Lyme disease, a tick-transmitted spirochetal illness, occurs in stages, with remissions and exacerbations and different clinical manifestations at each stage. The neurological abnormalities include aseptic meningitis, encephalitis, cranial neuritis, motor and sensory radiculitis, and myelitis in various combinations. They can be diagnosed serologically. However, it is possible that elevation levels of the antibody titers mean nonspecific damages of peripheral nerves. Further study is necessary to decide whether cases like ours suffer from so-called Lyme disease or not.