Title: Chronic Inflammatory Polyradiculoneuropathy (CIDP)
1Chronic Inflammatory Polyradiculoneuropathy (CIDP)
2Outline
- General
- Clinical Manifestations
- Diagnosis
- Treatment and prognosis
3CIDP
- Acquired, immune-mediated polyradiculoneuropathy
- Heterogeneous disorder with a wide range of
clinical expression ranging from subacute to a
progressive or relapsing-remitting course - Diagnosis is based on clinical symptoms and
signs, electrodiagnostic studies, CSF
examination, and other laboratory tests
4CIDP Clinical Manifestations
- Demyelination
- May be detected on nerve conduction studies or
nerve biopsy - Multifocal demyelination is a diagnostic hallmark
of CIDP, but distribution of demyelinative
lesions varies among patients - Weakness
- Characteristically, involves both proximal and
distal muscles - Typically symmetric, but can begin asymmetrically
- Sensory symptoms are common but motor symptoms
usually predominate - Autonomic system dysfunction can occur
5CIDP Clinical Manifestations
- Slow progressive course is seen in approximately
2/3 of cases - Children usually have a more precipitous onset of
symptoms - Relapsing course with partial or complete
recovery between recurrences is seen in
approximately 1/3 of cases - Periods of worsening and improvement usually last
weeks or months - Patients with a younger age of onset are said to
have a higher frequency of relapsing course
6CIDP Incidence
- In one study, prevalence was estimated to range
from 1-7.7 per 100,000 - These are likely underestimates, since the
criteria to select cases were strict - CIDP accounted for 13 of patients seen in one
neuromuscular center - Incidence increases with increasing age
- Children are rarely affected
7CIDP Pathophysiology
- In one study, CIDP occurred within a few weeks
after an infectious event in 16 of the patients - Because of the insidious onset, documenting
precipitating illnesses or events is very
difficult - Both respiratory and gastrointestinal infections
have been cited, but no causative organism has
been identified - With Guillain-Barre syndome, the most common
preceding infection is Campylobacter
Bouchard et al. NEUROLOGY 199952498503
8CIDP Regional Variants
- The classical phenotype that suggests CIDP is the
presence of proximal and distal weakness, with
large fiber sensory loss and areflexia - Few patients present with classic symtpoms
- Some authors have suggested subclassifications
based on the clinical phenotype in order to aid
in diagnosis and treatment - Currently these subclasses are not thought to be
distinct diseases
9CIDP Regional Variants
- Lewis-Sumner syndrome
- Distal acquired demyelinating sensory neuropathy
and sensory CIDP - Multifocal demyelinating neuropathy with
persistent conduction block - Distal CIDP
- Sensory CIDP
- ANTI-MAG (Myelin Associated Glycoprotein)
Neuropathy - CIDP with Hypertrophic nerves
- Subacute demyelinating polyneuropathy
- Chronic Inflammatory demyelinating neuropathies
10CIDP Associated Conditions
- Most frequently CIDP is an idiopathic illness
- Has been known to occur with several conditions
- In these cases, the associated condition is
included in the main diagnosis to separate those
cases from the idiopathic variety - Example CIDP with HIV infection
11CIDP Associated Conditions
- HIV infection
- Mild lymphocytic pleocytosis and increased gamma
globulin level in the CSF are seen frequently - Hodgkin lymphoma
- Associated neuropathy is not caused by direct
infiltration of the peripheral nerves but is a
consequence of the autoimmune cascade that occurs
with this disease, but the mechanism is not
completely clear - Paraproteinemias and/or plasma cell dyscrasias
12CIDP Associated Conditions
- CIDP is seen with monoclonal gammopathies (eg
MGUS), most frequently gammopathy of
immunoglobulin M (IgM) - Evidence suggests that CIDP with IgM MGUS has
specific clinical and electrophysiologic
characteristics - Usually predominance of distal weakness with
sensory symptoms greater than motor - Multiple sclerosis
- Reports describe CNS white matter changes in
patients with CIDP - Whether a true association exists between CIDP
and multiple sclerosis remains unclear
13CIDP Associated Conditions
- Systemic lupus erythematosus
- Chronic active hepatitis (B or C)
- CIDP associated with hepatitis should be
differentiated from cryoglobulinemic vasculitis - The latter causes either symmetric distal
sensorimotor polyneuropathy or mononeuropathy
multiplex but on pathologic examination shows
wallerian degeneration and not the segmental
demyelination seen in CIDP
14CIDP Associated Conditions
- Inflammatory bowel disease
- CIDP has been described in association with Crohn
disease and other inflammatory bowel conditions,
although no direct correlation between the two
afflictions is known - The mechanism of development of CIDP is presumed
to be an autoimmune abnormality that is also
causing the primary problem in inflammatory bowel
disease, although the details are not known
15CIDP Associated Conditions
- Diabetes mellitus
- Increasing evidence supports the suggestion that
some patients with diabetes who have severe
neuropathy or unusually progressive neuropathy
may have CIDP superimposed on their diabetic
disorder - Diabetes may predispose patients to CIDP
- Pregnancy
- Known to worsen CIDP
- Worsening usually occurs in the third trimester
or in the postpartum period
16CIDP Monitoring and Prognosis
- Sometimes difficult to assess the activity of a
chronic neuropathy - Nerve biopsy can be used to detect active nerve
lesions and inflammatory infiltrates - Axonal loss has more long-term prognostic impact
than active demyelination or inflammatory
infiltrates in demyelinating disorders of the
peripheral and central nervous systems
17CIDP Diagnosis
- The diagnosis of CIDP is typically based on the
clinical presentation, absence of other causes of
the neuropathic syndrome, and results of
electrodiagnostic studies - Presence of increased cerebrospinal fluid (CSF)
protein and demyelinating changes on nerve biopsy
are supportive of the diagnosis, but these are
not always present
18CIDP Diagnosis
- Because of the clinical heterogeneity and the
lack of a diagnostic test, various diagnostic
criteria have been proposed - In one series of patients all of whom had
proximal and distal weakness and in whom 95 of
patients had improvement with treatment, only 30
had the classic triad of slow nerve conduction
velocity, elevated CSF protein and demyelination
on nerve biopsy
19American Association of Neurology Criteria
- Developed criteria for the identification of
patients with CIDP for research studies - Pathologic criteria
- Electrophysiologic criteria Require 3
demyelinating range abnormalities (either slow
conduction velocity, prolonged distal motor
latencies or F wave latencies or conduction
block) in 2 nerves - Criteria are not sensitive and may miss more than
50 of patients with CIDP - Specificity approaches 100
- Majority of patients seen in clinical practice
fail to meet all of the criteria
20Laboratory Studies CSF
- Protein level is increased significantly in 80
of patients - Usually between 50 and 200 mg/dL, but can be
higher - 10 of patients also have mild lymphocytic
pleocytosis (lt50 cells) and increased gamma
globulin (usually associated with HIV infection) - CBC, sedimentation rate, antinuclear antibody,
biochemistry profile, and serum and urine
immunoelectrophoresis are necessary to exclude
important associated systemic disorders
21CIDP EMG
- Critical test to determine whether the disorder
is truly a peripheral neuropathy and whether the
neuropathy is demyelinating - Findings of a demyelinating neuropathy
- Multifocal conduction block or temporal
dispersion of compound muscle action potential - Prolonged distal latencies
- Variable conduction slowing to less than 70 of
normal - Absent or prolonged F wave latencies
- As the disease progresses, patients tend to
develop secondary axonal degeneration
22CIDP Peripheral nerve biopsy
- Indications
- Patients in whom the diagnosis is not completely
clear - Cases where other causes of neuropathy (eg,
hereditary, vasculitic) cannot be excluded - Caes where profound axonal involvement is
observed on EMG - Some experts recommend biopsy for most patients
prior to initiating immunosuppressive therapy
23CIDP Histologic Findings
- Interstitial and perivascular infiltration of the
endoneurium with inflammatory T cells and
macrophages with local edema - Evidence exists of segmental demyelination and
remyelination with occasional onion bulb
formation, particularly in relapsing cases - Some evidence of axonal damage also is observed,
with loss of myelinated nerve fibers - The inflammatory infiltrate with neutrophil
infiltration is observed in only a minority of
patients
24CIDP Histology
- Note the decreased density of nerve fibers
(arrows) - Demyelinated fibers (D)
- Fibers undergoing active macrophagemediated
demyelination (M)
Bouchard, et al. NEUROLOGY 199952498503
25CIDP Therapy
- Prednisone, IVIg and plasmapheresis have all been
demonstrated to be effective in controlled
clinical trials - In one study, response was seen to at least 1 of
these 3 main therapies in 66 of patients - Only 1/3 of patients have a sustained remission
after initial treatment and most require ongoing
treatment - Early treatment is advisable to prevent axonal
loss and motor neuron loss which leads to
functional decline - May be irreversible
26CIDP Therapy
- A positive therapeutic response is measured by
improvement or stabilization of previously
documented progressive weakness, sensory loss, or
ataxia - In responsive patients, treatment is continued
until maximal improvement or stabilization is
achieved, at which point it can be tapered or
discontinued - If there is further deterioration or a relapse,
the therapy can be re-instituted - Patients with chronic progressive disease require
maintenance therapy, although tapering the
treatment can be re-attempted periodically to
determine continued need
27CIDP Therapy
- Prednisone
- First line therapy
- Agents used for refractory patients
- Cyclosporine (Sandimmune, Neoral)
- Cyclophosphamide (Cytoxan)
- Azathioprine (Imuran)
- Mycophenolate (CellCept)
28CIDP Therapy
- Neuropathic pain
- Antiepileptics
- Carbamazepine (Tegretol)
- Gabapentin (Neurontin)
- Tricyclic antidepressants
- Amitriptyline (Elavil)
29CIDP Plasmapheresis
- Several controlled studies confirmed benefit
- Proposed mechanism
- Removal of antibodies and complement components
that are responsible for immune-mediated damage
of peripheral nerves - Has been shown to have similar efficacy as IVIg
in treatment of CIDP
30CIDP Plasmapheresis
- Treatment regimens
- Not standardized due to a lack of controlled
studies - Common regimen
- 3 plasma exchanges per week for first 2 weeks
- Additional treatment is determined by clinical
response
31IV Ig
- Solution composed mostly of heterogenous human
IgG but also small amounts of IgA and IgM - Proposed mechanism of action
- IVIg contains random set of antibodies that would
neutralize immune factors, causing damage to
peripheral nerve in CIDP - Activates complement cascade and provides
multitude of antibodies capable of neutralization
of many microorganisms, toxins, viruses, and
presumably autoantibodies
32IV Ig
- Used in infectious diseases to provide immediate
passive immunity in situations in which time
constraints do not allow development of active
immunity via vaccination - Also used to treat multiple immune-mediated
conditions, such as idiopathic thrombocytopenic
purpura, GBS, and myasthenia gravis
33CIDP IV Ig
- Several studies showed significant benefit in
CIDP - Useful alternative to plasmapheresis
- On average, improvement seen by day 10 and
continues through day 42 - Serum half-life is approximately 21-29 days
- Patients usually require repeated treatments
every few weeks or months to maintain remission
or treat recurrences
34CIDP Prognosis
- The outcome of CIDP is difficult to predict owing
to the variety of clinical patterns and evolution - If left untreated, it can become disabling, with
loss of ability to ambulate, work, or function
independently
35References
- Acquired demyelinating neuropathy. Brain. 119.
257270. - Ad Hoc Subcommittee of the American Academy of
Neurology, AIDS Task Force (1991). Research
criteria for diagnosis of chronic inflammatory
demyelinating polyradiculoneuropathy (CIDP).
Neurology. 41. 617618.
36References
- Bouchard, et al. Clinicopathologic findings and
prognosis of chronic inflammatory demyelinating
polyneuropathy. Neurology. February (1 of 1).
1999. 52. 498-503. - Kuwabara, S, et al. Distribution patterns of
demyelination correlate with clinical profiles in
chronic inflammatory demyelinating
polyneuropathy. Journal of Neurology
Neurosurgery and Psychiatry. 2002. 72. 37-42. - Latov N. Diagnosis of CIDP. Neurology. 59.
S2S6.