Gastrointestinal dysfunction in neurologic disease

Gastrointestinal motor dysfunctions result when extrinsic autonomic nerves are diseased and are unable to modulate the motor functions of the digestive tract, which depend on the enteric nervous system and the automaticity of the smooth muscles. Gut motor dysfunction may result from disorders at all anatomic levels of the extrinsic neural control and degeneration of gut smooth muscle. It illustrates the important modulation of gut motor function by the nervous system. Although much emphasis has been placed on dysphagia and constipation in neurologic disorders, more recent studies have highlighted incontinence, vomiting, and abdominal distention in the symptomatology of such patients. Strategies that evaluate the motor functions of the digestive tract and the extrinsic neural control are available; they aid in selection of rational therapies for these patients, which include physical therapy and biofeedback training (for dysphagia or incontinence), prokinetic agents (for neuropathic forms of gastroparesis, chronic intestinal dysmotility, or slow transit colonic disorders), and nutritional support using the enteral or parenteral route. Electrical or magnetic stimulation of lumbosacral roots provides a novel method to alleviate constipation in paraplegics.