Síndrome Neurológico Paraneoplásico: Enfermedad de neurona motora inferior, reporte de un caso

Abstract

A case of lower motor neuron disease is described, probably of paraneoplastic origin associated with follicular B cell lymphoma. Lower motor neuron disease is not one of the most common paraneoplastic neurological syndromes but is strongly associated with lymphomas. In this case the clinical findings of motor neuron disease started with generalized fasciculations, muscle atrophy with weakness in upper limbs and split hand deformity, also mild dysphonia. All this symptoms and findings could be consistent with primary motor neuron disease. There was no relationship with polyneuropathy because the nerve conductions did not show any alteration in sensory action potentials or blockages in motor nerve conduction. However, electromyography did clearly show a neuropathic pattern with marked denervation activity in the four spinal segments. Extension studies were carried out to exclude other conditions and thus establish primary motor neuron disease; nevertheless, multiple mediastinal nodes were reported on a chest tomography scan and hypermetabolic nodes were documented on the PET-Scan which clarified a baseline diagnosis. The patient received chemotherapy with stabilization of lower motor neuron syndrome.