What are the clinical features of Chronic Inflammatory Demyelinating Polyneuropathy (CIDP)?

Clinical Features of Chronic Inflammatory Demyelinating Polyneuropathy (CIDP)

CIDP is characterized by progressive weakness and sensory loss that develops over more than 2 months, distinguishing it from acute conditions like Guillain-Barré syndrome which progresses over days to weeks. 1, 2

Core Clinical Features

• Progressive, symmetric proximal and distal muscle weakness is the hallmark presentation, often affecting patients' ability to walk and perform activities of daily living independently 3
• Sensory dysfunction including paresthesias and sensory loss 4
• Reduced or absent tendon reflexes 4
• Symptoms typically progress over at least 8 weeks, with a relapsing-remitting or steadily progressive course 4, 2
• Motor symptoms often predominate over sensory symptoms in typical CIDP 5

Diagnostic Findings

• Cerebrospinal fluid analysis typically shows cytoalbuminologic dissociation (elevated protein with normal cell count) 1
• Electrophysiological studies demonstrate evidence of demyelination, which is crucial for diagnosis 1, 3
• MRI of the brachial or lumbosacral plexus may show focal or diffuse peripheral nerve abnormalities 1
• Nerve biopsy may be useful in evaluating atypical forms of CIDP 1

CIDP Variants

• Typical CIDP: Symmetric proximal and distal weakness with motor-predominant manifestations 5
• Multifocal Acquired Demyelinating Sensory and Motor Neuropathy (MADSAM or Lewis-Sumner Syndrome): Characterized by asymmetric involvement with preserved reflexes in areas not affected by weakness 1, 6
• Distal Acquired Demyelinating Symmetric Neuropathy: Predominantly distal symmetric presentation 6

Associated Symptoms

• Cranial nerve involvement may occur 4
• Autonomic symptoms are possible but less common than in Guillain-Barré syndrome 2
• Ataxia and neuropathic pain can be present 4
• Dysphagia may occur in some cases 7

Distinguishing Features from Guillain-Barré Syndrome

• CIDP progresses over more than 2 months, while GBS progresses over days to 4 weeks 1, 2
• CIDP is less likely to have autonomic nervous system involvement, facial weakness, or preceding infectious illness compared to GBS 2
• CIDP rarely requires mechanical ventilation compared to GBS 2
• Treatment-related fluctuations (TRF) can occur in both conditions, but deterioration after 9 weeks from onset or three or more deteriorations suggests CIDP rather than GBS-TRF 2

Immunopathogenesis

• Typical CIDP shows demyelination predominantly affecting distal nerve terminals and nerve roots where the blood-nerve barrier is deficient, suggesting antibody-mediated demyelination 5
• MADSAM variant shows multifocal demyelination in nerve trunks, likely involving cellular immunity in the breakdown of the blood-nerve barrier 5
• Some patients harbor antibodies against nodal proteins such as neurofascin and contactin-1 6

Demographic Features

• Unlike many autoimmune diseases, CIDP generally affects older individuals 4
• Male predominance is observed 4

Pitfalls in Diagnosis

• Misdiagnosis is common due to lack of a specific biomarker 3
• Interpreting electrodiagnostic testing and cerebrospinal fluid findings must be done in light of the clinical phenotype 3
• Other conditions to consider in differential diagnosis include diabetic polyradiculoneuropathy, leptomeningeal metastases, infectious causes, systemic inflammatory disorders, and peripheral neuropathies associated with metabolic disorders, toxins, or nutritional deficiencies 1

Understanding these clinical features is essential for early recognition and appropriate management of CIDP, which can significantly impact patient outcomes and quality of life.