How well do you know the European guideline on CIDP diagnosis and treatment?

European Academy of Neurology/Peripheral Nerve Society guideline on diagnosis and treatment of chronic inflammatory demyelinating polyradiculoneuropathy

• The guideline was revised to update the 2010 consensus guideline on chronic inflammatory demyelinating polyradiculoneuropathy (CIDP).

• The revision was based on the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology and formulated evidence-based recommendations and consensus-based Good Practice Points for clinical practice.

• The diagnosis of CIDP relies on a combination of clinical, electrophysiological, and laboratory features with exclusions to eliminate other disorders that may mimic CIDP.

• Good Practice Points were formulated for supportive criteria and investigations to be considered to diagnose CIDP.

• The levels of diagnostic certainty were reduced from three to only two because the diagnostic accuracy of criteria for probable and definite CIDP did not significantly differ.

• Typical CIDP and CIDP variants were distinguished, and the previous term "atypical CIDP" was replaced by "CIDP variants" because these are well-characterized entities.

• The principal treatment recommendations were intravenous immunoglobulin (IVIg) or corticosteroids as initial treatment in typical CIDP and CIDP variants, plasma exchange if IVIg and corticosteroids are ineffective, and IVIg as first-line treatment in motor CIDP (Good Practice Point).

• For maintenance treatment, IVIg, subcutaneous immunoglobulin, or corticosteroids are recommended, and if the maintenance dose of any of these is high, consider either combination treatments or adding an immunosuppressant or immunomodulatory drug (Good Practice Point).

• If pain is present, consider drugs against neuropathic pain and multidisciplinary management (Good Practice Point).

• The evidence from randomized clinical therapeutic trials has significantly increased since 2010 and allows evidence-based recommendations about treatments according to GRADE.

• The guideline revision attempts to improve specificity of the criteria.

• The evidence from randomized clinical therapeutic trials has significantly increased since 2010 and allows evidence-based recommendations about treatments according to GRADE.Guideline on Diagnosis and Treatment of Chronic Inflammatory Demyelinating Polyradiculoneuropathy

• The guideline was developed by a task force using a GRADE Evidence-to-Decision framework.

• Strong recommendations were made when the majority of informed people would choose the recommended course of action, weak recommendations were made when a substantial number would not.

• The clinical criteria for CIDP were refined into "typical CIDP" and "CIDP variants".

• CIDP variants are well-characterized entities that share the common features of demyelination and response to immune therapy, but differ in clinical and electrodiagnostic phenotype.

• The diagnostic workflow and differential diagnosis may differ between typical CIDP and CIDP variants.

• Electrodiagnosis is strongly recommended to support the clinical diagnosis of typical CIDP and CIDP variants.

• The levels of electrodiagnostic certainty were reduced from three to two (CIDP and possible CIDP) because of empirical evidence showing no significant difference in sensitivity and specificity.

• There is no gold standard for the diagnosis of CIDP, and the label "definite CIDP" was avoided.

• Motor and sensory conduction studies are required to define the diagnostic categories of typical CIDP and CIDP variants.

• Disorders not classified as CIDP include chronic immune sensory polyradiculopathy (CISP) and autoimmune nodopathies.

• CISP may be immune-mediated and respond to immune treatment, but there is not enough evidence to determine if it is demyelinating or related to sensory CIDP.

• Antibodies against nodal-paranodal cell-adhesion molecules have been discovered in a small subset of patients fulfilling CIDP criteria.Electrodiagnostic Criteria and Good Practice Points for Chronic Inflammatory Demyelinating Polyradiculoneuropathy (CIDP)

• Electrodiagnostic criteria for CIDP have been established using a frequency filter bandpass of 2 Hz to 10 kHz for all parameters.

• To apply motor nerve conduction criteria, the median, ulnar, peroneal, and tibial nerves on one side are tested.

• Sensory conduction abnormalities must be present in at least two nerves for the diagnosis of CIDP.

• Motor conduction criteria fulfillment is required in at least two nerves to confirm the clinical diagnosis of distal CIDP.

• Extensiveness of motor nerve conduction studies depends on the nerve affected and may require collision techniques to avoid ulnar nerve components in the median nerve CMAP.

• Sensory CIDP with normal motor nerve conduction studies needs to fulfill sensory nerve conduction criteria.

• Multifocal CIDP requires motor conduction criteria fulfillment in at least two nerves in total in more than one limb.

• Focal CIDP requires motor conduction criteria fulfillment in at least two nerves in one limb.

• Motor CIDP must fulfill motor conduction criteria in at least two nerves and sensory conduction must be normal in all of at least four nerves.

• Sensory CIDP must fulfill sensory conduction criteria and motor conduction must be normal in all of at least four nerves.

• An objective response to treatment with immunomodulatory agents supports the clinical diagnosis of CIDP if clinical, electrodiagnostic, and other supportive criteria only allow for a diagnosis of possible CIDP.

• Ultrasound is a low-cost, widely available, non-invasive procedure with moderate diagnostic accuracy and may be used to support the diagnosis of CIDP.Diagnosis and Treatment of Chronic Inflammatory Demyelinating Polyradiculoneuropathy (CIDP)

• CIDP may respond to treatment, but careful consideration is needed to avoid overdiagnosis.

• MRI can aid in the diagnosis of CIDP by showing nerve root enlargement and/or increased signal intensity.

• Ultrasound can be used to diagnose CIDP in patients fulfilling diagnostic criteria for possible CIDP.

• There is currently no evidence to support MRI in pediatric patients.

• CSF protein is often increased in CIDP patients, but specificity for CIDP is uncertain.

• CSF analysis should be considered to exclude other diagnoses or to support the diagnosis of CIDP.

• Nerve biopsy should not be performed as a routine procedure to diagnose CIDP but may be considered in specific circumstances.

• Testing for nodal and paranodal antibodies is advised in CIDP patients with certain features.

• Monoclonal gammopathy testing is strongly advised in adult patients with a clinical suspicion of CIDP.

• SFLC testing may detect abnormalities not otherwise detected.

• Conditions under which MRI may be considered in patients fulfilling only possible electrodiagnostic criteria include unavailability of ultrasound or when ultrasound results are non-contributory.

• The independent diagnostic value of CSF testing remains unproven.

Revised electrodiagnostic criteria for chronic inflammatory demyelinating polyneuropathy (CIDP)

• The Task Force (TF) recommends electrodiagnosis (nerve conduction studies) to support the clinical diagnosis of typical CIDP and CIDP variants.
• The levels of electrodiagnostic certainty have been reduced from three to two (CIDP and possible CIDP).
• The TF requires not only motor but also sensory conduction studies to define the diagnostic categories of typical CIDP and CIDP variants.
• To confirm the clinical diagnosis of typical CIDP, at least two motor nerves must have abnormalities which fulfil the motor conduction criteria.
• In patients suspected of having typical CIDP who do not fulfil minimal electrodiagnostic criteria, the diagnosis of possible typical CIDP may be made if there is objective improvement following treatment with IVIg, corticosteroids, or plasma exchange and if at least one additional supportive criterion is fulfilled.
• Motor conduction criteria fulfilment is required in at least two upper limb nerves to confirm the clinical diagnosis of distal CIDP.
• Motor conduction criteria fulfilment is required in at least two nerves in total in more than one limb to confirm the clinical diagnosis of multifocal CIDP and in at least two nerves in one limb for the diagnosis of focal CIDP.
• Motor CIDP must fulfil motor conduction criteria in at least two nerves and sensory conduction must be normal in all of at least four nerves to confirm the clinical diagnosis of motor CIDP.
• Sensory CIDP must fulfil sensory conduction criteria and motor conduction must be normal in all of at least four nerves to confirm the clinical diagnosis of sensory CIDP.
• Supportive criteria, such as response to treatment, imaging, cerebrospinal fluid, or nerve biopsy, may support the diagnosis of CIDP in patients who fulfil clinical criteria but whose electrodiagnostic criteria only allow for possible CIDP.
• Sensory nerve conduction studies have been removed as general supportive criteria, except for diagnosing patients with sensory CIDP without motor nerve conduction abnormalities.
• The recommendation of the TF for electrodiagnostic testing in patients with clinically suspected CIDP is based on the very good diagnostic accuracy of 2010 EFNS/PNS electrodiagnostic criteria.

Revised electrodiagnostic criteria for chronic inflammatory demyelinating polyneuropathy (CIDP)

• The Task Force (TF) recommends electrodiagnosis (nerve conduction studies) to support the clinical diagnosis of typical CIDP and CIDP variants.
• The levels of electrodiagnostic certainty have been reduced from three to two (CIDP and possible CIDP).
• The TF requires not only motor but also sensory conduction studies to define the diagnostic categories of typical CIDP and CIDP variants.
• To confirm the clinical diagnosis of typical CIDP, at least two motor nerves must have abnormalities which fulfil the motor conduction criteria.
• In patients suspected of having typical CIDP who do not fulfil minimal electrodiagnostic criteria, the diagnosis of possible typical CIDP may be made if there is objective improvement following treatment with IVIg, corticosteroids, or plasma exchange and if at least one additional supportive criterion is fulfilled.
• Motor conduction criteria fulfilment is required in at least two upper limb nerves to confirm the clinical diagnosis of distal CIDP.
• Motor conduction criteria fulfilment is required in at least two nerves in total in more than one limb to confirm the clinical diagnosis of multifocal CIDP and in at least two nerves in one limb for the diagnosis of focal CIDP.
• Motor CIDP must fulfil motor conduction criteria in at least two nerves and sensory conduction must be normal in all of at least four nerves to confirm the clinical diagnosis of motor CIDP.
• Sensory CIDP must fulfil sensory conduction criteria and motor conduction must be normal in all of at least four nerves to confirm the clinical diagnosis of sensory CIDP.
• Supportive criteria, such as response to treatment, imaging, cerebrospinal fluid, or nerve biopsy, may support the diagnosis of CIDP in patients who fulfil clinical criteria but whose electrodiagnostic criteria only allow for possible CIDP.
• Sensory nerve conduction studies have been removed as general supportive criteria, except for diagnosing patients with sensory CIDP without motor nerve conduction abnormalities.
• The recommendation of the TF for electrodiagnostic testing in patients with clinically suspected CIDP is based on the very good diagnostic accuracy of 2010 EFNS/PNS electrodiagnostic criteria.

Good Practice Points for Diagnosis of Chronic Inflammatory Demyelinating Polyneuropathy (CIDP)

• Ultrasound can be used to diagnose CIDP in adult patients who meet diagnostic criteria for possible CIDP, but not for CIDP.
• Nerve enlargement of at least two sites in proximal median nerve segments and/or the brachial plexus is a characteristic feature of CIDP.
• Cross-sectional area median nerve >10 mm2 at forearm, >13 mm2 upper arm, >9 mm2 interscalene (trunks), or >12 mm2 for nerve roots may support the diagnosis of CIDP.
• There is no evidence to support the use of ultrasound in pediatric patients with suspected CIDP.
• MRI should not be used to diagnose CIDP in adult patients, except for those who meet diagnostic criteria for possible CIDP, but not for CIDP.
• Enlargement and/or increased signal intensity of nerve root(s) on T2 weighted MRI sequences may suggest CIDP.
• Quantitative assessment of spinal nerve root sizes or semi-quantitative scoring of abnormalities of the spinal nerve roots and trunks may aid in the diagnosis of CIDP.
• There is no evidence to support the use of MRI in pediatric patients with suspected CIDP.
• CSF analysis should not be performed if diagnostic criteria are already met.
• CSF analysis may be considered to exclude other diagnoses or to support the diagnosis of CIDP in certain circumstances, such as acute or subacute onset or suspected infectious or malignant etiology.
• CSF protein elevation should be interpreted cautiously in the presence of diabetes.
• There is insufficient research to establish rigorous cut-offs for CSF protein levels to support a diagnosis of CIDP, particularly in individuals older than 50 years.

Good Practice Points for Diagnosis of Chronic Inflammatory Demyelinating Polyneuropathy (CIDP)

• Ultrasound can be used to diagnose CIDP in adult patients who meet diagnostic criteria for possible CIDP, but not for CIDP.
• Nerve enlargement of at least two sites in proximal median nerve segments and/or the brachial plexus is a characteristic feature of CIDP.
• Cross-sectional area median nerve >10 mm2 at forearm, >13 mm2 upper arm, >9 mm2 interscalene (trunks), or >12 mm2 for nerve roots may support the diagnosis of CIDP.
• There is no evidence to support the use of ultrasound in pediatric patients with suspected CIDP.
• MRI should not be used to diagnose CIDP in adult patients, except for those who meet diagnostic criteria for possible CIDP, but not for CIDP.
• Enlargement and/or increased signal intensity of nerve root(s) on T2 weighted MRI sequences may suggest CIDP.
• Quantitative assessment of spinal nerve root sizes or semi-quantitative scoring of abnormalities of the spinal nerve roots and trunks may aid in the diagnosis of CIDP.
• There is no evidence to support the use of MRI in pediatric patients with suspected CIDP.
• CSF analysis should not be performed if diagnostic criteria are already met.
• CSF analysis may be considered to exclude other diagnoses or to support the diagnosis of CIDP in certain circumstances, such as acute or subacute onset or suspected infectious or malignant etiology.
• CSF protein elevation should be interpreted cautiously in the presence of diabetes.
• There is insufficient research to establish rigorous cut-offs for CSF protein levels to support a diagnosis of CIDP, particularly in individuals older than 50 years.