********** Guillain-Barre syndrom...

**********

Guillain-Barre syndrome (GBS) is an surname for a heterogeneous group of immune-mediated peripheral neuropathies. A feature universal in all GBS variants is a rapidly evolving polyradiculoneuropathy preced by means of a triggering event, most frequently an infection. (1) GBS generally manifests as a symmetric motor paralysis with or without sensory and autonomic disturbances.

Population-based scrutinizes attempting to document the annual incidence of GB have been convoyed in various countries worldwide and generally are in agreement upon a rate of 1 to 3 for 100,000 persons annually. (2,3) GB present itselfs in all age groups, although rarely in infants, and the incidence varies. From birth to 30 years, the annual incidence is fairly uniform at 13 to 19 by 100,000. Peaks are noted in late adolescence and young adulthood, as well as in the somewhat advanced in life The first peak likely correlates with increased risk of cytomegalovirus and Campylobacter jejuni infection. The reason for the peak in the somewhat advanced in life is unknown but is postulated to be caused according to failing immune suppressor mechanisms. 2 Another variation in incidence is originate in pregnant and postpartum women According to a Swedish epidemiologic cogitation (4) the incidence appears to be lower during pregnancy with an increase in the month immediately after delivery.

The patient with GB typically existings with weakness accompanied by tingling dysesthesias in the extremities. This weakness is prominent in the proximal muscles; leg are more frequently affected than arms. Paresthesias appear spreading proximally but seldom extending past the wrists and ankles. astute tendon reflexes disappear within the first small in number days of symptom onset.

The progressive phase of the syndrome lasts from a scarcely any days to four weeks. About 73 percent of patients reach a nadir of clinical function at individual week and 98 percent at four weeks. (5) The progressive phase is followed according to a plateau phase of persistent, unchanging symptoms. Improvement will begin within days of the plateau. The time to resolution of symptoms varies among patients.

Cranial might involvement may affect airway maintenance, facial muscles, judgment movements, and swallowing. Patients should be hospitalized for observation. Approximately 30 percent of patients will require ventilatory assistance at a time during the illness. (2) Poor issues primarily are associated with the increasing severity of disease, with a mortality rate as high as 20 percent occurring primarily in patients who require mechanical ventilation. (6)

Pain, another usual feature of GBS, is seen in approximately united half of all patients and is sometimes described as sharp occurring with even the slightest of motions Pain is most severe in the shoulder girdle, back, and posterior thighs. (78) Patients complain of a down-reaching aching pain in the weakened muscles that is similar to the muscular discomfort experienced following exercise. Pain may be accompanied at muscle cramps, and it is chiefly severe at night.

Diagnosis

GB is the principally common type of rapidly evolving, generalized peripheral nervous plan disorder. However, several disorders can be mistaken for GB particularly early in its course (Table 1) (7)

The diagnosis of GB is based upon typical clinical features; electrodiagnostic examination and examination of the cerebrospinal fluid (CSF) can aid in the diagnosis (Table 2) (79) Electrodiagnostic findings suggestive of GB include an absent H retroactive low amplitude or absent sensory self-command action potentials, an abnormal F wave, and other les haunt abnormalities. These findings may allow earlier intervention with specific treatments, if it be not that a definitive diagnosis is usually not possible until the fifth day after the attack of symptoms. (10)

Characteristic CSF findings consist of elevated protein (higher than 055 g by dL [5.5 g per L]) without pleocytosis (abnormal number of enclosed spaces in the CSF). CSF is frequently normal when symptoms have been existing for less than 48 hours, however by the end of undivided week the level of CSF protein is elevated. An increased white posterity cell count in CSF (10 to 100 through [mm.sup.3] [10 to 100 x [10sup6] by L]) in a patient with typical GB symptoms increases the possibility of Lyme disease, neoplasia, human immunodeficiency virus (HIV) infection, sarcoid meningitis, or other diseases. (711)

GB has five distinct subtypes: acute inflammatory demyelinating polyradiculoneuropathy (AIDP), acute motor axonal neuropathy (AMAN), acute motor sensory axonal neuropathy (AMSAN), Miller Fisher syndrome and acute panautonomic neuropathy. The axonal forms are generally conceit to have poorer prognoses, indicating a ne for determining the specific subtype These subtype are distinguished electrodiagnostically and pathologically (Table 3) (212-16)

Antecedent Events

Acute infectious illnesses are well-known antecedent results in two thirds of patients who have GB Cross-reactivity between the pathogen and the force tissue sets up the autoimmune answer Patients commonly report a respiratory tract infection or gastroenteritis that resolv when the neuropathy began. Campylobacteriosis is the greatest in quantity common precipitant in GBS.