EpistemisMultiple mononeuropathy
Specialty: Neurology.
Why it occurs
- Systemic vasculitis of medium or small vessels (Polyarteritis nodosa, Granulomatosis with polyangiitis, rheumatoid vasculitis, Churg-Strauss) with multifocal ischemia of the vasa nervorum
- Diabetes mellitus (asymmetric ischemic neuropathy)
- Multifocal motor neuropathy with conduction blocks (autoimmune demyelinating disease mimicking ALS)
- Hereditary or acquired amyloid neuropathy
- Mixed cryoglobulinemia associated with hepatitis C infection
- Sarcoidosis or leprosy (direct infiltration of multiple nerve trunks)
Initial workup
Electromyogram and nerve conduction velocities to confirm the pattern of asymmetric multifocal mononeuropathy (axonal vs demyelinating); targeted nerve and muscle biopsy (typically of the sural or superficial peroneal nerve) to document necrotizing vasculitis of the vasa nervorum; complete analytical profile (ANA, ANCA, rheumatoid factor, cryoglobulins, HBV, HCV and HIV serology).
red flags
Quickly appearing and intensely painful motor weakness in one foot (foot drop due to involvement of the external popliteal sciatic) followed a few days later by weakness in the contralateral hand (hand drop due to involvement of the radial), associated with fever, weight loss, palpable purpura on the skin or hematuria, indicative of acute necrotizing systemic vasculitis (rheumatological and neurological emergency).
Standard management
- Methylprednisolone (intravenous boluses of 500-1000 mg daily for 3 days followed by oral prednisone) combined with intravenous Cyclophosphamide or Rituximab if autoimmune vasculitic etiology is confirmed
- Intravenous immunoglobulin — if Multifocal Motor Neuropathy with conduction blocks is confirmed
- Gabapentin or Pregabalin for associated severe neuropathic pain.
Educational guidance for study. It is NOT a prescription recommendation. The actual choice depends on the cause, the patient, and current guidelines.
- Area
- Neurology
- Listed causes
- 6
- Treatment options
- 3