Published Oct 17, 2009
jess41378
25 Posts
If someone can give me insight as to the difference between polyneuritis and CIDP (chronic inflammatory demyelinating polyneuritis). I have patients with these disorders but not sure the difference.
exw18
1 Post
just found this great article.
http://emedicine.medscape.com/article/1169959-overview
acute inflammatory demyelinating polyradiculoneuropathy
author: tarakad s ramachandran, mbbs, frcp©, facp, professor of neurology, clinical professor of medicine, clinical professor of family medicine, clinical professor of neurosurgery, state university of new york upstate medical university; chair, department of neurology, crouse irving memorial hospital
coauthor(s): richard a sater, md, phd, consulting staff, high point neurological associates
[color=#004276]contributor information and disclosures
updated: jan 15, 2009
introduction
background
acute inflammatory demyelinating polyneuropathy (aidp) is an autoimmune process that is characterized by progressive areflexic weakness and mild sensory changes. sensory symptoms often precede motor weakness. about 20% of patients end up with respiratory failure. many variants exist. in the west, the most common presentation is a subacute ascending paralysis. this is associated with distal paresthesias and loss of deep tendon reflexes. progression is often maximal by the end of 4 weeks, then the condition usually plateaus before slowly improving. in 1859, landry described 10 cases characterized by ascending paralysis and sensory changes. during world war i, guillain, barré, and strohl described a series of patients with a similar presentation and decreased or absent deep tendon reflexes. they also described albuminocytologic dissociation in the cerebrospinal fluid (csf), ie, increased csf protein in the absence of increased wbcs. this allowed them to differentiate aidp from poliomyelitis, the most common acute paralytic syndrome of that era. (aidp often is referred to as [color=#004276]guillain-barré syndrome [gbs]).
myelin breakdown and axonal degeneration were observed in nerve biopsies from patients with aidp by haymaker and kernohan in 1949.[url=http://javascript:showcontent('active','references')][color=#004276]1 [/url]an allergic etiology was suggested by krucke in 1955 after he observed lymphocytic infiltrates within biopsy specimens.[url=http://javascript:showcontent('active','references')][color=#004276]2 [/url]an autoimmune process was supported by waksman and adams when they created the experimental allergic neuritis model by injecting peripheral nerve tissue into rodents.[url=http://javascript:showcontent('active','references')][color=#004276]3 [/url]
pathophysiology
acute inflammatory demyelinating polyneuropathy is believed to be caused by an immunologic attack that is directed against myelin components. this results in a demyelinating polyneuropathy. both cellular and humoral immune mechanisms appear to play a role. early inflammatory lesions consist of a lymphocytic infiltrate that is adjacent to segmental demyelination. macrophages are more prominent several days later. the peripheral nerve changes consist of varying degrees of perivascular edema, accumulations of mononuclear cells, and paranodal and less commonly, segmental demyelination. they are often multifocal with some predilection for the nerve roots, sites of entrapment, and distal ends. in the axonal variant of guillain-barré syndrome, axonal degeneration often predominates. severe guillain-barré syndrome is often associated with axonal degeneration as well, which results in wallerian degeneration. axonal degeneration occurs either as a primarily axonal process or as a bystander-type axonal degeneration, associated with demyelination. rarely, the pathologic process extends into the central nervous system.
as the regeneration occurs, nerve sprouting and increased scarring often results.
with electron microscopy, macrophages are observed stripping off the myelin sheath. humoral molecules such as antimyelin antibodies and complement likely contribute to the process by directing macrophages to schwann cells by opsonization. indeed, complement and antibodies have been found to coat the myelin sheath. the changes are observed in nerve roots, peripheral nerves, and cranial nerves. in acute motor axonal neuropathy (aman, an aidp variant), deposited complement is found at the nodes of ranvier, while myelin often is left undamaged.
damage to the myelin sheath leads to segmental demyelination. this results in decreased nerve conduction velocity and, at times, conduction block. in this current review, aidp refers to the more common demyelinating form unless otherwise specified.
frequency
united states
acute inflammatory demyelinating polyneuropathy is the most common acquired demyelinating polyneuropathy. the incidence is 0.6-1.7 cases per 100,000 per year. no significant seasonal variation has been noted.
international
frequency is not well documented. of 2 predominant guillain-barré syndrome subtypes, a demyelinating subtype (aidp) predominates in the united states and europe, and axonal subtype (aman) is the predominant form in china. previous clinical studies suggested that aman also occurs in mexican children.[url=http://javascript:showcontent('active','references')][color=#004276]4 [/url]similar outbreaks have been reported in mexico, spain, and jordan.
mortality/morbidity
in 3 recent large studies, mortality rate ranged from 2-6%.
race
acute inflammatory demyelinating polyneuropathy occurs in all races and in all regions of the world.
sex
the male-to-female ratio is 1.1-1.7:1.
age
patients have ranged in age from 2 months to 95 years.
clinical
history
[*]sensory symptoms
[*]autonomic dysfunction
[*]pain
[*]aidp may vary early in the course. more than 95% of patients eventually have the classic symptoms; other patients may have one of the characterized variants.
physical
a detailed physical examination can help support the diagnosis of acute inflammatory demyelinating polyneuropathy and/or exclude disorders in the differential diagnosis.
[*]deep tendon reflexes
[*]findings that are inconsistent with a diagnosis of aidp
[*]diagnostic criteria for guillain-barré syndrome include the presence of progressive weakness and areflexia, relative symmetry, mild sensory involvement, cranial nerve involvement, at least partial recovery, autonomic dysfunction, and absence of fever. cerebrospinal fluid features that strongly support the diagnosis are an increase in protein beyond the first week, cell count
[*]in 1986, ropper described 3 patients who experienced acute progression of oropharyngeal, neck, and shoulder weakness. clinically, they had facial palsy, blepharoptosis, absence of sensory disturbance, and preserved tendon jerk in the legs. based on elevated csf protein levels and electrophysiological findings (a denervation pattern and decreased conduction velocity in peripheral nerves), he speculated that these patients had a guillain-barré syndrome variant, which he called pharyngeal-cervical-brachial weakness (pcb).[url=http://javascript:showcontent('active','references')][color=#004276]5 [/url]
since then, pcb is considered a rare variant of guillain-barré syndrome. nagashima et al identified the clinical profiles of pcb. they feel that the clinical overlapping, frequent campylobacter jejuni infection, and common antiganglioside antibodies present in pcb, guillain-barré syndrome, fisher syndrome, and bickerstaff brainstem encephalitis provide conclusive evidence that pcb and these conditions form a continuous spectrum.[url=http://javascript:showcontent('active','references')][color=#004276]6 [/url]
causes
acute inflammatory demyelinating polyneuropathy is thought to be caused by a dysregulated immune response against myelin. this response may be triggered by several illnesses and conditions. two thirds of patients with aidp recall an antecedent upper respiratory or gastrointestinal infection or syndrome from 1-6 weeks prior to the onset of weakness.
[*]bacterial
[*]other: rare cases of aidp in individuals infected with toxoplasma, malaria, or filaria have been reported.
[*]vaccination
[*]malignancies and systemic illnesses
[*]pregnancy: most cases occur during the last trimester or during the first 2 weeks of the postpartum period.
[*]bone marrow transplantation
[*]surgery: most patients also had an infection or blood transfusion.
[*]other problems to be considered
[*]variants
[*]comparison of clinical features of guillain-barré syndrome with cidp
more on acute inflammatory demyelinating polyradiculoneuropathy
overview: acute inflammatory demyelinating polyradiculoneuropathy differential diagnoses & workup: acute inflammatory demyelinating polyradiculoneuropathytreatment & medication: acute inflammatory demyelinating polyradiculoneuropathyfollow-up: acute inflammatory demyelinating polyradiculoneuropathy
differential diagnoses
[color=#004276]orificenic
[color=#004276]organophosphates
[color=#004276]brainstem gliomas
[color=#004276]periodic paralyses
[color=#004276]brucellosis
[color=#004276]sarcoidosis and neuropathy
[color=#004276]chronic inflammatory demyelinating polyradiculoneuropathy
[color=#004276]spinal cord hemorrhage
[color=#004276]diabetic neuropathy
[color=#004276]spinal epidural abscess
[color=#004276]lambert-eaton myasthenic syndrome
[color=#004276]systemic lupus erythematosus
[color=#004276]leptomeningeal carcinomatosis
[color=#004276]thyroid disease
[color=#004276]lyme disease
[color=#004276]toxic neuropathy
[color=#004276]myasthenia gravis
[color=#004276]organic solvents
other problems to be considered
heavy metal poisoning
period paralyses, usually hypokalemic
poliomyelitis
acute porphyric neuropathy
buckthorn shrub poisoning
botulism
collagen vascular diseases
critical illness polyneuropathy
cytomegalovirus (cmv) infection
diphtheria
ebv virus infection (infectious mononucleosis)
hiv infection
hypophosphatemia
lead poisoning
malingering and conversion reaction
spinal injury
tick paralysis and related disorders
workup
laboratory studies
[*]some patients have oligoclonal banding of the csf.
[*]myelin basic protein also is increased in some patients.
[*]more than 90% of patients have fewer than 10 wbc/µl, with a mean of 3 wbc/µl. if more than 50 wbc/µl are present, an alternative diagnosis should be considered, including hiv, lyme disease, polio, or other infections. patients with hiv-associated aidp often have >50 wbc/µl (mean, 23 wbc/µl).
[*]in non-hiv cases, the cells are overwhelmingly lymphocytes, whereas a nonlymphocytic pleocytosis is seen in patients with hiv.
[*]blood tests have little role in the diagnosis of aidp but may help to exclude other conditions and to serially monitor patients with aidp in the hospital (especially those who are critically ill).
[*]urine tests to exclude heavy metal intoxication may be necessary in some patients.
[*]stool cultures may confirm c jejuni enteritis. patients with this condition may have a more aggressive course and a slightly worse prognosis.
imaging studies
[*]chest radiography in children may reveal a pattern that is consistent with mycoplasmal pneumonia. additionally, chest and abdominal radiography may be necessary in critically ill patients to evaluate for possible pneumonia and ileus.
other tests
[*]needle emg can document the extent of denervation.
[*]findings of other electrophysiologic tests, such as blink reflexes, phrenic nerve conduction, and somatosensory evoked responses, may be abnormal but do not offer any advantages to typical ncs studies.
[*]autonomic tests such as sympathetic skin responses and cardiovagal testing may be indicated in patients with autonomic failure.
[*]pulmonary function tests, useful in determining the timing of intensive care unit (icu) transfers and elective intubation, should be performed in all patients.
[*]electrocardiography (ecg) and cardiac monitoring can be helpful when arrhythmias occur. other possible abnormalities include atrioventricular block, qrs widening, and t-wave abnormalities.
[*]jin et al measured the csf tau protein levels in 26 patients with guillain-barré syndrome. the levels of the poor outcome group (hughes grade at 6 months was between ii and vi, n = 6) were higher than those of the good outcome group (0 or i, n = 20) (p :showcontent('active','references')'>[url=http://javascript:showcontent('active','references')][color=#004276]11 [/url]
procedures
lumbar puncture is performed to obtain csf for analysis (see [color=#004276]lab studies).
histologic findings
nerve biopsy is seldom required to diagnose acute inflammatory demyelinating polyradiculoneuropathy. however, in patients with prolonged clinical courses, histologic examination can help to differentiate cidp from aidp. nerve biopsies in aidp show an inflammatory infiltrate during the first few days. later on, macrophages are seen, sometimes with myelin stripping. axons are usually spared. under electron microscopy, macrophages (which are stripping myelin) are seen beneath the basement membrane and are usually advancing along the minor dense line.
acute inflammatory demyelinating polyradiculoneuropathy: treatment & medication
treatment
medical care
advances in supportive medical care have resulted in improved survival rates in acute inflammatory demyelinating polyneuropathy (aidp).
surgical care
tracheostomy is necessary in many intubated patients. those requiring long-term enteral nutrition typically require a gastrostomy or jejunostomy.
consultations
diet
no special diet is required.
activity
keep patients ambulatory if they are able to walk without assistance. most patients who are admitted to the hospital require bedrest.
medication
immunomodulatory therapy with either ivig or plasmapheresis has been demonstrated to result in more rapid recovery of aidp than other treatments or no treatment. recent large studies have demonstrated that the 2 treatments are equal in efficacy. bedridden and critically ill patients also require treatment to prevent complications. the mechanism of action of plasma exchange is not known. suggested mechanisms include the removal of antibody, complement components, immune complexes, lymphokines, and acute-phase reactants. the generally recommended regimen includes every other day plasma exchange, totaling 6 exchanges in 2 weeks, with 3-3.5 l exchanged per treatment. if venous access is not of sufficient quality to ensure rapid blood withdrawal, a central line should be a consideration (in about 20% of cases).
plasmapheresis (pe) is more frequently associated with severe adverse effects requiring cessation of therapy, including a bleeding diathesis. in addition, pe requires special, appropriate equipment and trained personnel. also, younger children may be at risk for bleeding after insertion of wide catheters. transient hypotension, which might occur, is corrected by adjusting the inflow-to-outflow ratio. other common side effects include paresthesias, and rarely hypersensitivity reactions and hypocalcemia.
immunomodulatory agents
aidp is believed to be caused by immune dysregulation resulting from an attack against myelin. therapy directed at the immune system can result in more rapid recovery. ivig is especially proven highly effective in children.
iv immunoglobulin (ivig) or gamma globulin (many manufacturers)
ivig is prepared from serum pooled from many donors by fractionation and purification. most manufacturers include a detergent step to help prevent spread of viruses. mechanism of action is poorly understood. however, it is believed to act by down-regulating antibody and cytokine production and by neutralizing antibodies specific for myelin. also appears to down-regulate pro-inflammatory cytokines, such as il-1 and gamma-ifn. other proposed mechanisms are fc receptor blockade and interference with complement cascade (ie, interfering with opsonization).
adult
0.4 g/kg/d for 5 d has been used most often
alternative regimen is 1-2 g/kg/d for 2 d
pediatric
administer as in adults
follow-up
further inpatient care
based on the severity of symptoms, patients with acute inflammatory demyelinating polyradiculoneuropathy (aidp) may require further inpatient services.
further outpatient care
transfer
complications
critically ill patients are susceptible to the same complications as other intubated patients, including pneumonia, sepsis, skin decubiti, deep venous thrombosis, and urinary tract infections. patients with aidp have some unique complications that may cause significant morbidity, the most common being pain, labile blood pressure, and increased sensitivity to cardiac medications.
prognosis
[*]death occurs in only 2-6% of patients and is usually due to cardiac arrest, ards, pulmonary embolism, severe bronchospasm, pneumonia, or sepsis.
[*]about 10% of patients have a relapse 1-6 weeks after completing immunomodulatory therapy. these patients can be treated with a second course of immunomodulation.
[*]fewer than 1% of patients have aidp 1 or more years after onset of symptoms. in some cases, the recurrence follows immunization. this recurrence differs from cidp.
[*]sporadic cases of recurrent guillain-barré syndrome[url=http://javascript:showcontent('active','references')][color=#004276]13 [/url]and rare cases of recurrent guillain-barré syndrome after a long asymptomatic period[url=http://javascript:showcontent('active','references')][color=#004276]14 [/url]have been reported. some authors consider recurrent guillain-barré syndrome a variant of cidp, while others maintain that they are 2 different entities.martic et al describe a patient who developed guillain-barré syndrome as a child and experienced a full relapse after 19 years with another innocuous episode 10 years later.[url=http://javascript:showcontent('active','references')][color=#004276]15 [/url]
[*]several prognostic factors have been identified.
[*]in spite of therapy with plasma exchange or ivig, the decrease in mortality has often been attributed to improved aggressive supportive treatment than to any drug treatment. this has included close monitoring with the avoidance of hypoxia, pain, and arrhythmogenic stimuli.
patient education
[color=#004276]guillain-barré syndrome foundation international
miscellaneous
medicolegal pitfalls
the main medicolegal pitfalls involve not anticipating progression of symptoms.
special concerns
references