[A case of motor neuropathy with pyramidal sign due to prolonged administration of high dose of pancuronium bromide (Myoblock)].
We reported a case of motor neuropathy with pyramidal sign following prolonged administration of a high dose of muscle relaxant, pancuronium bromide (Myoblock). A 40-year-old male was admitted to our hospital with acute episode of pancreatitis. He was treated with artificial ventilation and Myoblock to manage delirious state, disseminated intravascular coagulation and multiple organ failure. Total dose of 823 mg (24 mg/day) of Myoblock was given intravenously over 36 days. After Myoblock was discontinued, he regained his consciousness and marked muscle weakness with atrophy was noted in both limbs, more severe in distal lower limbs, without any noticeable sensory and sphincter disturbances. Motor nerve conduction studies showed normal nerve conduction velocities with markedly decreased amplitude of compound muscle action potentials. Repetitive nerve stimulation studies revealed decrement response after tetanic stimulation, which disappeared later. Needle EMG showed active denervation potentials and marked polyphasic motor unit potentials. Muscle biopsy revealed neurogenic muscle atrophy with fragmented acetylcholine esterase-positive postsynaptic sites. Sural nerve biopsy showed slight to moderate degree of axonal degeneration of myelinated fibers. Clinical, electrophysiological, and pathological studies above indicated that the main affected sites were neuromuscular junctions including the terminal twigs of motor neurones and postsynaptic membrane, and pyramidal tracts, predominant in lower limbs. About one month after the recognition of the muscle weakness, his muscle strength improved gradually, however, spasticity with hyperreflexia and pathologic reflexes of both legs were found, and became more prominent thereafter. Intensive physiotherapy and rehabilitation led improvement to the point that he became able to ambulate with walking-aids about 7 months later, but marked spasticity persisted.(ABSTRACT TRUNCATED AT 250 WORDS)
Miyoshi
T
T
Department of Neurology, Kyushu Rosai Hospital.
Ohnishi
A
A
Yamaguchi
Y
Y
D000208:Acute Disease; D000328:Adult; D006801:Humans; D008297:Male; D016472:Motor Neuron Disease / Q000139:chemically induced* / Q000503:physiopathology; D010195:Pancreatitis / Q000139:chemically induced; D010197:Pancuronium / Q000008:administration & dosage / Q000009:adverse effects*; D011712:Pyramidal Tracts / Q000503:physiopathology*; D013997:Time Factors
D010197:Pancuronium