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Peripheral Neuropathy, Emergency Medicine

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Peripheral Neuropathy, Emergency Medicine

Basics

Description

Etiology

Diagnosis

Signs and Symptoms

Peripheral neuropathy is a general term for peripheral nerve disorders that may affect motor, sensory, or vasomotor nerve fibers and presents with marked muscle weakness, atrophy pain and numbness ‚

Variable, depending on presentation of symptoms; refer to Differential Diagnosis ‚

Absence of reflexes early in course could represent demyelinating neuropathy such as Guillain " “Barre syndrome (acute inflammatory demyelinating syndrome [AIDP]). ‚

Stable respiratory and gait status with outpatient follow-up ‚

Primary care or neurology depending on etiology and severity of symptoms ‚

Failure to diagnose Guillain " “Barre syndrome (AIDP) ‚

  • Sensory nerve dysfunction:NumbnessLocalized tinglingParesthesiasDysesthesiasVibration and position sensations are decreased with large-fiber neuropathyPain and temperature sensation are decreased with small-fiber neuropathyDeep tendon reflexes are decreased secondary to decreased sensation of afferent limb
  • Motor nerve dysfunction:Weakness:Distal > proximalOccasionally fasciculationsMuscle atrophy, diminished tone with long-standing motor nerve involvementLoss of reflexes secondary to slowing of conduction along motor nerve efferent limb
  • Autonomic nerve dysfunction:OrthostasisConstipationUrinary retentionImpotence
  • Numbness
  • Localized tingling
  • Paresthesias
  • Dysesthesias
  • Vibration and position sensations are decreased with large-fiber neuropathy
  • Pain and temperature sensation are decreased with small-fiber neuropathy
  • Deep tendon reflexes are decreased secondary to decreased sensation of afferent limb
  • Weakness:Distal > proximalOccasionally fasciculations
  • Muscle atrophy, diminished tone with long-standing motor nerve involvement
  • Loss of reflexes secondary to slowing of conduction along motor nerve efferent limb
  • Distal > proximal
  • Occasionally fasciculations
  • Orthostasis
  • Constipation
  • Urinary retention
  • Impotence
  • Duration of symptoms
  • Symmetric or asymmetric symptoms
  • Distal or proximal symptoms
  • Motor, sensory, or mixed
  • Thorough head-to-toe physical exam
  • Focus on neurologic exam:Motor weaknessSensory loss typically in stocking-glove distribution
  • Motor weakness
  • Sensory loss typically in stocking-glove distribution

Essential Workup

  • Studies based on acuteness, severity of neuropathy, and most likely diagnosis
  • Neurologic consult early if acute and severe symptoms

Diagnosis Tests & Interpretation

  • Basic metabolic panel
  • CBC
  • Liver function tests
  • Urinalysis
  • Thyrotropin-stimulating hormone
  • HIV or vitamin B12 based on individual presentations
  • Electrocardiogram
  • CXR if indicated
  • Head CT if indicated
  • Electromyographic studies, nerve conduction studies, and nerve biopsy per neurologic consult on admission or outpatient follow-up
  • Lumbar puncture as appropriate for AIDP

Differential Diagnosis

  • Focal:EntrapmentCommon sites of compression:Carpal, ulnar tunnelTarsal tunnelPeronealMyxedemaRheumatoid arthritisAmyloidosisAcromegalyTraumaIschemic lesionsDiabetes mellitus (DM)VasculitisLeprosySarcoidosisNeoplastic infiltration or compression
  • Multifocal (mononeuropathy multiplex):DMVasculitis:Polyarteritis nodosaSystemic lupus erythematosusSj ƒ ¶gren syndromeSarcoidosisLeprosyMalignancy relatedHIV/AIDSHereditary predisposition to pressure palsies
  • Symmetric:Endocrine:Most common is DMHypothyroidismMedications:IsoniazidLithiumMetronidazolePhenytoinCimetidineHydralazineAmitriptylineAmiodaroneNutritional diseases:AlcoholismB12/folate deficiencyThiamineCritical illness neuropathyHypophosphatemiaGuillain " “Barre syndrome (AIDP)Toxic neuropathy:Carbon monoxideAcrylamideCarbon disulfideEthylene oxideOrganophosphate estersLead
  • Myelopathy mimicking peripheral neuropathy
  • Back pain
  • Saddle anesthesia
  • Lower extremity weakness
  • Entrapment
  • Common sites of compression:Carpal, ulnar tunnelTarsal tunnelPeroneal
  • Myxedema
  • Rheumatoid arthritis
  • Amyloidosis
  • Acromegaly
  • Trauma
  • Ischemic lesions
  • Diabetes mellitus (DM)
  • Vasculitis
  • Leprosy
  • Sarcoidosis
  • Neoplastic infiltration or compression
  • Carpal, ulnar tunnel
  • Tarsal tunnel
  • Peroneal
  • DM
  • Vasculitis:Polyarteritis nodosaSystemic lupus erythematosusSj ƒ ¶gren syndrome
  • Sarcoidosis
  • Leprosy
  • Malignancy related
  • HIV/AIDS
  • Hereditary predisposition to pressure palsies
  • Polyarteritis nodosa
  • Systemic lupus erythematosus
  • Sj ƒ ¶gren syndrome
  • Endocrine:Most common is DMHypothyroidism
  • Medications:IsoniazidLithiumMetronidazolePhenytoinCimetidineHydralazineAmitriptylineAmiodarone
  • Nutritional diseases:AlcoholismB12/folate deficiencyThiamine
  • Critical illness neuropathy
  • Hypophosphatemia
  • Guillain " “Barre syndrome (AIDP)
  • Toxic neuropathy:Carbon monoxideAcrylamideCarbon disulfideEthylene oxideOrganophosphate estersLead
  • Most common is DM
  • Hypothyroidism
  • Isoniazid
  • Lithium
  • Metronidazole
  • Phenytoin
  • Cimetidine
  • Hydralazine
  • Amitriptyline
  • Amiodarone
  • Alcoholism
  • B12/folate deficiency
  • Thiamine
  • Carbon monoxide
  • Acrylamide
  • Carbon disulfide
  • Ethylene oxide
  • Organophosphate esters
  • Lead

Treatment

Pre-Hospital

  • Pain control as needed
  • Airway protection as indicated

Initial Stabilization/Therapy

Ed Treatment/Procedures

  • Variable depending on acuity of symptoms
  • Discontinuation offending toxin or agent
  • Treatment underlying systemic disease

Medication

  • Variable depending on underlying diagnosis
  • Opioid analgesics
  • Gabapentin 300 mg PO daily then BID on day 2, then TID on day 3 up to 1,800 mg/d div. TID
  • Carbamazepine 100 mg PO BID for trigeminal neuralgia
  • IV immunoglobulin for Guillain " “Barre syndrome (AIDP)

Follow-Up

Disposition

  • Respiratory distress or acute gait disturbance
  • Intractable pain

Followup Recommendations

Pearls and Pitfalls

Additional Reading

  • Azhary ‚ H, Farooq ‚ MU, Bhanushali ‚ M, et al. Peripheral neuropathy: Differential diagnosis and management. Am Fam Physician. 2010;81:887 " “892.
  • Gilron ‚ I, Watson ‚ CP, Cahill ‚ CM, et al. Neuropathic pain: A practical guide for the clinician. CMAJ. 2006;175:265 " “275.
  • Marx ‚ JA, Hockberger ‚ RS, Walls ‚ RM, et al. Rosens Emergency Medicine: Concepts and Clinical Practice. 7th ed. St. Louis, MO: Mosby; 2009.
  • Pascuzzi ‚ RM. Peripheral neuropathy. Med Clin North Am. 2009;93:317 " “342.

Codes

ICD9

  • 356.9 Unspecified hereditary and idiopathic peripheral neuropathy
  • 782.0 Disturbance of skin sensation

ICD10

  • G62.9 Polyneuropathy, unspecified
  • R20.0 Anesthesia of skin
  • R20.2 Paresthesia of skin

SNOMED

  • 302226006 peripheral nerve disease (disorder)
  • 44077006 Numbness (finding)
  • 91019004 Paresthesia (finding)
  • 62507009 Pins and needles (finding)