A 60-year-old female was admitted because of intermittent
fever,
arthralgia,
itching of whole body, pretibial
edema,
urinary incontinence,
pain of both legs and gait disturbance, after an
insect bite. On admission, she had
fever of 38 degrees C, and nuchal
pain and stiffness. Neurological examination revealed spasticity of lower legs and increased deep tendon reflexes of all extremities.
Hyperesthesia and
hyperalgesia were noted on C2-4 and L5-S5 areas. Leukocyte count was 10,100/mm3 and CRP was 2+. CSF showed no
pleocytosis (3/mm3, lymphocyte), but total
protein (50 mg/dl) and
IgG (10.5 mg/dl) were increased. On T2-weighted images of brain MRI, multiple small high signal areas were shown. The symptom improved markedly by
prednisolone, but 3 months later left lateral gaze
palsy appeared abruptly. A demyelinating lesion of the pons to the medulla oblongata including the left paramedian pontine reticular formation was suspected, and a
corticosteroid pulse
therapy was very effective. Serum titer of anti-Borrelia burgdorferi-
IgG antibody by indirect immunoperoxidase method was 400 x at first and 1600 x after 3 months. Neuroborreliosis was diagnosed, but high doses of intravenous
penicillin were not effective, and an immune-mediated demyelinating mechanism was probably thought to play a role in the pathogenesis of neuroborreliosis.