Letters to the Editor
Lyme-Related Relapsing Motor Neuron Disease
to the editor- Motor neuron disease (particularly amyotrophic lateral sclerosis (ALS), is generally considered to be a progressive nonremitting disease. Lyme neuroborreliosis is reported to cause various neurologic syndromes affecting both the central and peripheral nervous systems, including a rare association with amyotrophic lateral sclerosis. (1) Relapsing MND is distinctly uncommon.
A 71-year old woman presented in 1989 with symptoms of Parkinson's disease.
She was treated with levodopa and improved. In May 1990, she presented with fulminant weakness, dyspnea ( labored or difficult breathing), and shaking chills. Testing revealed an erythrocyte sedimentation (ESR) rate of 93 mm/ph negative antinuclear antibody (ANA) , normal cteatine phosphokinase (CPK), polyclonal increase on immunoelectrophoresis , positive Lyme immunoblot for the 41 and 55kda bands, and Lyme enzyme- linked immunosorbent assay (ELISA) wiht IgM 1.63 mpr,a; (<0.8) . Cerebrospinal fluid analysis was normal. Temporal artery biopsy was normal. Nerve conduction studies (NCV) were normal. Electromyography (EGM) revealed diffuse fasiculations, high-amplitude polyphasia, and giant motor unit action potentials with decreaed recruitment pattern consistent with MND.
Muscle biopsy revealed neurogenic atrophy.
The patient was placed on ceftriaxone 2 g. intravenously daily for 3 weeks. The patients's strength improved.
Repeated EMG in October 1990 revealed absent fasiculations, improved insertational activity with continued decreased recruitment pattern. The patient continued to improve, and EMG in August 1990 showed normal motor unit potentials.
In September 1992, the patient presented with diffuse weakness, hyper-reflexia with extensor plantar responses. Cerebrospinal fluid was normal. Western blot for Lyme disease was negative, and B 12 levels were normal. The ESR was elevated. She was placed on ceftriaxone 2 g. daily with rapid improvement. On swithching to oral antibioitcs, she relapsed in November 1992, becoming unable to ambulate across a room. Restitution of intravenous ceftriaxone resulted in marked improvement. On examination in June 1993, patient exhibited hyperreflexia, left clonus with extersor plantar response, but well maintained strength. EMG did not reveal any evidence of active devervation, but polyphasia was still present.
This patient exhibited a fluctuating course of relapse and remission of MND over a 3-year period. Repeat neurophysiologic studies appeared consistent with MND rather than a syndrome mimicking it ( i.e., polyneuropathy and radiculopathy). Evaluation suggested an initial acute presentation of Lyme neuroborreliosis. The mechanism of repeated improvements or exacerbations is unclear. Previous explanations include an intrinsic beneficial effect of third generation cephalosporins.
1. Halperin JJ, Kaplan GP, et al. Immunologic reactivity against Borrelia burgdorferi in patients with motor neuron disease. Arch. Neurol., 47:586-594, 1990. 2. Smith L, Improvement of patient with amyotrophic lateral sclerosis given ceftriaxone. Lancet 339:1417, 1992.
