Guillain-Barrés syndrome (GBS), also known as acute infectious polyradiculoneuritis, is an autoimmune disease caused by viral infection or post-infection and other causes. Its main pathological change is widespread inflammatory demyelination of the peripheral nervous system. The main clinical manifestation is symmetric flaccid paralysis of the extremities.
I. Clinical manifestations
The onset of the disease is often preceded by prodromal symptoms of upper respiratory or gastrointestinal tract infection, such as fever and diarrhea.
2.Motor disorders
(1) Limb paralysis: symmetrical lower motor neuron paralysis of the extremities, often starting from the lower extremities and gradually spreading to both upper extremities, or from one side to the other. In very few patients, the paralysis is first limited to both lower limbs. The disease usually progresses to its peak within 1 to 2 weeks and then stabilizes. The paresis is usually more proximal, with hypotonia of the extremities, diminished or absent tendon reflexes, normal abdominal wall and testicular reflexes, and pathological reflex signs due to cone bundle involvement in a few cases. Myasthenia gravis gradually appears 2-3 weeks after the onset of the disease.
(2) Trunk muscle paresis: cervical muscle paresis is unable to raise the head. Respiratory muscle paralysis (20%-30%) may occur in cases of intercostal muscle and diaphragm paralysis, manifested as chest tightness, shortness of breath, low voice (like a cat’s cry), weak cough, inability to lie down, reduced thoracic or abdominal respiratory motion (usually intercostal muscle paralysis earlier than diaphragm) and reduced respiratory sounds, which may lead to coma and death in severe cases due to hypoxia or respiratory complications.
(3) Cerebral nerve palsy: About half of the patients may have cerebral nerve damage, with peripheral paralysis of the linguopharynx, vagus and one or both facial nerves being the most common, followed by the motoneurium, talipes, and adductor nerve. Occasionally, optic disc edema is seen, which may be due to inflammatory changes in the optic nerve itself or cerebral edema; it may also be related to the significant increase in cerebrospinal fluid protein, which blocks the arachnoid villi and affects the absorption of cerebrospinal fluid.
3.Sensory disturbance is often the first symptom, mainly subjective sensory disturbance, mostly starting from numbness and pins and needles sensation at the end of the limbs. The pain is often increased by pulling the nerve roots during examination (e.g., positive Kernig’s sign), and there may be obvious pressure pain in the muscles (especially in the bilateral gastrocnemius). On objective examination, there may be glove or garter-like and/or hyperalgesia in the trigeminal innervation area, or there may be no sensory disturbance. Sensory impairment is much milder than motor impairment, which is one of the characteristics of the disease.
4, autonomic dysfunction The initial or recovery period is often sweaty and smelly, which may be the result of sympathetic nerve stimulation. A few patients may have short-term urinary retention at the beginning, which may be caused by temporary dysfunction of the autonomic nerves innervating the bladder or damage to the spinal nerves innervating the external sphincter. Some patients may develop cardiovascular dysfunction such as unstable blood pressure, tachycardia and abnormal electrocardiogram.
Second, auxiliary examination
Lumbar puncture: Cerebrospinal fluid shows protein cell separation 1 to 2 weeks after the onset of the disease, and is most significant in the 2nd to 8th week, and gradually recovers later. The white blood cell count does not exceed 10×106/L. The cytological classification is dominated by lymphocytes and monocytes, and macrophages can be seen. The protein content was significantly increased. Sugar and chloride were normal.
Electrophysiological examination: motor nerve conduction velocity is significantly slowed, and prolonged or absent F-wave latency is seen in demyelinating GBS. in case of AMAN, motor nerve conduction velocity is normal or mildly slowed. The F-wave latency of sensory fibers is normal or mildly prolonged.
III. Treatment
1. Immunotherapy
Immunoglobulin, plasma exchange or a combination of both, hormone therapy is controversial, B vitamins and promotion of nerve function recovery.
2. Symptomatic treatment
①Strengthen the maintenance of respiratory function and keep the airway unobstructed: for those who may develop respiratory muscle paralysis, if the patient has developed superficial breathing, increased frequency or weak cough and poor sputum evacuation, early tracheotomy and mechanical ventilation are appropriate. At this time, resuscitation treatment in the neurological intensive care unit is required.
② Prevention and treatment of pulmonary complications: regular turning and back patting, regular adequate aspiration, and attention to aseptic operation, prevention of pulmonary infection, and early selection of appropriate antibiotics.
③Prevent electrolyte disorders, and in hospitals with conditions, cardiac and pulmonary function monitoring should be performed in critically ill patients.
④Ensure adequate nutrition, water and rest: adequate rest is very important for the preservation of physical strength and the enhancement of resistance to disease, so appropriate benzodiazepine sedatives can be used for those who are irritable and poorly rested. Fresh whole blood or plasma can be transfused regularly. For those who have difficulty in swallowing, nasal feeding can be used as early as possible to ensure adequate nutrition, water and medication, and to reduce the occurrence of aspiration pneumonia.
3.Recovery treatment
During the recovery period, continue to use B vitamins and drugs to promote the recovery of nerve function, and use physical therapy, body therapy, acupuncture and massage and other rehabilitation measures as appropriate.
IV. Prognosis
Most of the patients have a good prognosis after active treatment. Most of the mild cases improve in 1 to 3 months and recover completely within a few months to 1 year, while some patients may have different degrees of sequelae, such as limb weakness, muscle atrophy and foot drop. Severely ill patients have difficulty recovering from limb paralysis and often die due to respiratory muscle paralysis, medullary paralysis or pulmonary complications. A small number of cases may recur.