Neurologic manifestations associated with cryoglobulinemia: A single center experience

Limited information is available describing the spectrum of neurological complications of cryoglobulinemia.

Single center retrospective review of patients with neurologic symptoms and elevated serum cryoglobulins, with their potential association being classified as definite, possible, or unlikely using defined criteria.

Among 492 patients, 131 (87 classified as definite and 44 as possible) had neurologic symptoms associated with cryoglobulinemia. Common comorbidities included hepatitis C (N = 43), monoclonal gammopathy of undetermined significance (N = 20), Sjogren's syndrome (N = 17), membranoproliferative glomerulonephritis (N = 17), and systemic lupus erythematosus (N = 10). Features supporting an association between cryoglobulinemia and neurological symptoms were the presence of purpura (p < .001), positive rheumatoid factor (p = .001) and low C4 (p = .002). Common peripheral neurological diagnoses were symmetric polyneuropathy (N = 84), small fiber neuropathy (N = 25), and mononeuritis multiplex (N = 16). Central neurological manifestations were infrequent and included seizures (N = 3), posterior reversible encephalopathy syndrome (N = 2), intracerebral hemorrhage (N = 1), vasculitis (N = 1), rapidly progressive dementia (N = 1), lymphoma (N = 1), and myelitis/meningitis (N = 1). Treatments utilized included corticosteroids (N = 74), rituximab (N = 42), cyclophosphamide (N = 27), methotrexate, azathioprine, or mycophenolate mofetil (N = 28), anti-viral therapy (N = 20), plasmapheresis (N = 16), and intravenous immunoglobulin (N = 20). Neurologic symptoms associated with cryoglobulinemia remained stable or improved in 86% of patients.

This study describes a wide spectrum of patients with neurologic symptoms attributed to cryoglobulinemia and provides a framework to approach this challenging diagnosis.