Progressive motor quadriparesis with wasting: a diagnostic conundrum

Area of Science:

• Neurology
• Clinical Electrophysiology

Background:

• Pure motor quadriparesis with bulbar involvement and lower motor neuron signs presents a diagnostic challenge.
• Differentiating motor neuron disease from its mimics requires careful clinical and electrophysiological assessment.

Observation:

• A man in his early 30s presented with a 9-month history of slowly progressive, asymmetrical pure motor quadriparesis and bulbar symptoms.
• The patient exhibited diffuse lower motor neuron involvement without upper motor neuron signs and experienced significant weight loss.

Findings:

• Clinical and electrophysiological evaluation ultimately diagnosed Lambert-Eaton myasthenic syndrome, a rare neuromuscular junction disorder.
• The case highlights the importance of recognizing atypical presentations that mimic motor neuron disease.

Implications:

• Accurate diagnosis of rare neuromuscular disorders like Lambert-Eaton myasthenic syndrome is crucial for appropriate management.
• Understanding the diagnostic nuances of pure motor quadriparesis aids in differentiating it from more common neurological conditions.