GBS is a clinical syndrome characterized by acute paralysis that occurs is associated with the autoimmune process in which the target is the peripheral nerves, roots, and cranial nerves.
ETIOLOGY
The etiology of GBS is still not yet known certainly. The theory adopted today is an aberration immunobiologic, both primary immune response or immune mediated process. Latent period between infection and symptoms polineuritis gives the notion that the abnormalities are likely caused by an allergic reaction in response to peripheral nerve. In many cases, the infection was not previously found, except sometimes the peripheral nerves and ventral and dorsal spinal cord, there were also disturbances in the spinal cord and medulla oblongata.
Some conditions / diseases that precede and perhaps something to do with the occurrence of GBS, among others:
1. Viral or bacterial infection
GBS often associated with acute non-specific infection. Incidence of GBS cases associated with this infection approximately between 56% - 80%, ie 1 to 4 weeks before neurological symptoms occur such as upper respiratory tract or gastrointestinal infection. Acute infections are associated with GBS:
a. Viruses: CMV, EBV, HIV, varicella-zoster virus, Vaccinia / smallpox, influenza, Measles, Mumps, Rubella, hepatitis, Coxsackie, Echo.
b. Bacteria: Campylobacter, Jejeni, Mycoplasma, Pneumonia, Typhoid, Borrelia B, paratyphoid, Brucellosis, Chlamydia, Legionella, Listeria.
2. Vaccination
3. Surgery, anesthesia
4. Systemic diseases, such as malignancy, systemic lupus erythematosus, thyroiditis, and Addison's disease
5. Pregnancy or the puerperium
6. Endocrine Disorders
CLINICAL MANIFESTATIONS1. Latent periodThe time between infected or prodromal state that preceded it and the onset of neurological symptoms. The length of this latent period ranged from one to 28 days, an average of 9 days. In this latent period there has been no clinical symptoms that arise.
2. Clinical Symptomsa. ParalysisThe main clinical manifestation is the paralysis of the muscles of the lower extremity motor neurone type of muscles of extremities, body and sometimes also the face. In most patients, paralysis of both lower extremities begins later spread asenderen to the body, upper limbs and cranial nerves. Sometimes it can also be subjected to all four limbs simultaneously, and then spread to the body and cranial nerves. Paralysis of these muscles and is followed by a symmetrical or arefleksia hyporefleksia. Usually the degree of paralysis of the muscles of the proximal portion is more severe than the distal, but it can also same, or distal parts more severe thanproximal part.
b. Impaired sensibilityParesthesias are usually more obvious on the distal extremities, the face can also be charged with distribution sircumoral. Objective sensory deficit is usually minimal and often with the pattern of distribution such as socks and gloves. Ekstroseptif sensibility more commonly affected than on proprioceptive sensibility. Muscle pain often encountered after physical activity.
c. Cranial nerveCranial nerve is most commonly affected is N. VII. Paralysis of the facial muscles often begins on one side but then soon became bilateral. All the cranial nerves may be subject except NI and N. VIII. Diplopia can occur as a result of N. N. IV or III exposed. When the N. IX and NX exposed will cause a disruption in the form of difficult swallowing, dysphonia and in severe cases cause respiratory failure due to n. laryngeal paralysis.
d. Impaired autonomic functionImpaired autonomic function is found in 25% of patients with GBS. The disorder is a tachycardia or bradycardia less frequently, red face (facial flushing), fluctuating hypertension or hypotension, loss of sweating or episodic profuse diaphoresis. Urinary retention or urinary incontinence is rarely encountered. Autonomic disorders are rarely settled more than one or two weeks.
e. Respiratory failureRespiratory failure is a major complication that can be fatal if not treated properly. Respiratory failure caused by paralysis of the diaphragm and the paralysis of respiratory muscles, which is found in 10-33 percent of patients.
f. PapilledemaSometimes found papilledema, the cause is not known with certainty. Presumably because the elevation levels of protein in the muscles that cause blockage of fluid arachoidales villi that absorption of cerebrospinal fluid is reduced.
PATHOPHYSIOLOGYMyelinated axons conducts of nerve impulses faster than the unmyelinated axons. Along the way the myelinated fibers interference occurs in the membranes (node Ranvier) where direct contact between the membrane of axons of cells with extracellular fluid. Highly permeable membrane at the node, so that conduction be good. Movement of ions into and out axons can occur rapidly only at the Ranvier nodes, so that impulses along nerve fibers bermielin can jump from one node to another node (conduction salsatori) with sufficiently strong. In GBS, the myelin membranes that surround the axons lost. Myelin membrane is quite susceptible to injury because many agents and conditions, including physical trauma, hypoxemia, toxic chemicals, vascular insufficiency, and immunological reactions. Demyelination is a common response of neural networks against many adverse conditions. Loss of myelin fibers in Guillain - Barre Syndrome makes salsatory conduction unlikely to occur, and the transmission of nerve impulses
canceled. Mechanisms of how infections, vaccinations, trauma, or other factors that precipitate the occurrence of acute demyelination in GBS is still not known with certainty. Many experts conclude that the nerve damage that occurs in this syndrome is through an immunologic mechanism (the process of antibody response against viruses or bacteria) that cause damage to the nervous edge to paralysis evidence that imunopatogenesis is the mechanism that causes peripheral nerve injury in this syndrome are :
1. Obtainment of antibodies or cellular immune response (keen mediated immunity) against infectious agents on peripheral nerve.
2. Presence of auto antibodies against peripheral nervous system
3. Accumulation of antigen antibody complexes acquired from circulation in the blood vessels peripheral nerves causing peripheral nerve demyelination process. Demyelination process of peripheral nerve in GBS is influenced by the response of cellular immunity and humoral immunity triggered by previous events, the most common viral infection.
Due to an infection or certain circumstances will arise that precedes GBS autoantibodies or cellular immunity against the network system peripheral nerves. Meningococcal infections, viral infections, syphilis or trauma to the spinal cord, can lead to adhesion- arachnoid membrane attachment. In tropical countries the cause is an infection of tuberculosis. In certain places the attachment post-infection can ensnare ventral roots (dorsal root as well). Because not all ventral roots exposed, but mostly on the cliquegroups , the root-root of the cervical and lumbosacral diinstrumensia are most commonly affected by the attachment of post-infection. Therefore LMN paralysis most often found in the muscles of the limbs, the muscles around the shoulder and hip joints. Paralysis of the arm with a sensory deficit on both legs or the muscles of the limbs. Pathologically found myelin degeneration with edema that may or without cell infiltration. Infiltration consisting of mononuclear cells. These cells infiltrate mainly composed of small lymphocytes, medium and looks too, macrophages, and polymorphonuclear cells at the beginning of the disease. After that comes the plasma cells and mast cells. Segmental nerve fibers and axonal degeneration. These lesions be limited to the proximal segments and spinal roots or spread along peripheral nerves. Predilection for the spinal roots allegedly due to lack of effective permeability between the blood and nerves in the area.