Rosen & Barkin's 5-Minute Emergency Medicine Consult (84 page)

• A careful history is essential since gait changes may be caused by pain, weakness, lightheadedness, vertigo, or incoordination
  
• Onset:
  
  • Hours–days: Acute
    
  • Weeks–months: Subacute
    
  • Months–years: Chronic
    
• Symmetric or focal symptoms
  
• Presence of fever, mental status changes, weakness, sensory loss, or urinary incontinence
  
• Recent viral illness or immunizations
  
• History of trauma or toxic ingestion
  
• Family history of movement disorder
  

• Perform a complete physical exam, including neurological and gait testing
  
• Assess for signs or symptoms of acute, life-threatening disorders such as hemorrhage, stroke, or CNS infection:
  
  • Altered mental status
    
  • Headache
    
  • Focal neurological deficits
    
  • Elevated intracranial pressure:
    
    • Bradycardia, HTN, abnormal respiratory pattern
      
    • Papilledema
      
    • Bulging fontanelles
      
  • Fever
    
  • Meningismus
    
  • Nystagmus
    
  • Nausea/vomiting
    
  • Examine ears and perform provocative testing for nystagmus (Dix–Hallpike)
    
• Note the presence of intoxication or toxidromes in patients with suspected ingestion
  

A detailed history and physical exam will help determine which tests are necessary

• Blood glucose level
  
• Serum electrolytes
  
• Toxicology screen:
  
  • Standard panels may not include the drugs of interest in the ataxic patient
    
• Thyroid function testing
  
• Target additional testing to likely exposures, such as anticonvulsants
  

• CT:
  
  • Head CT can identify mass, hemorrhage, subacute infarct, or hydrocephalus
    
  • Consider CT with and without IV contrast if mass suspected
    
  • CT angiography can be performed to evaluate for vascular disease
    
• MRI:
  
  • Excellent study to evaluate for acute ischemia, mass, demyelinating lesions, and vascular abnormalities
    
  • Superior for imaging the posterior fossa
    
  • MR angiography of head/neck may be indicated if vascular abnormality is suspected
    
• EKG:
  
  • Not indicated as part of ataxia workup, but may be useful in evaluation of nonspecific dizziness
    

• Lumbar puncture:
  
  • Indicated if infection or Guillain–Barré suspected
    

• Acute symmetric ataxia:
  
  • Head trauma
    
  • Drug use/toxic ingestion:
    
    • Alcohol
      
    • Lithium
      
    • Phenytoin
      
    • Barbiturates
      
    • Carbamazepine
      
    • Phenobarbital
      
    • Valproic acid
      
    • Benzodiazepines
      
    • Diphenhydramine
      
    • Dextromethorphan
      
  • Acute viral cerebellitis
    
  • Meningitis/encephalitis
    
  • Hydrocephalus
    
  • Postinfectious syndrome
    
  • Hypoglycemia
    
  • Hyponatremia
    
  • Severe heat stroke
    
• Acute focal ataxia:
  
  • Posterior circulation infarction
    
  • Anterior cerebral artery syndrome
    
  • Vertebrobasilar insufficiency (VBI)
    
  • Cerebellar hemorrhage
    
  • Subdural hematoma
    
  • Cerebellar abscess
    
  • Acute disseminated encephalomyelitis
    
  • Complicated migraine
    
  • Atypical seizure
    
• Subacute symmetric ataxia:
  
  • Drug use/toxic ingestion:
    
    • Mercury
      
    • Lead
      
    • Hydrocarbons
      
    • Glue sniffing
      
    • Cytotoxic chemotherapy
      
    • Organophosphates
      
  • Vitamin B
    ₁
    or B
    ₁₂
    deficiency
    
  • Paraneoplastic syndromes:
    
    • Breast/ovarian cancer
      
    • Hodgkin lymphoma
      
    • Neuroblastoma
      
  • Lyme disease
    
  • Toxoplasmosis
    
  • Creutzfeldt–Jakob disease
    
• Subacute focal ataxia:
  
  • Cerebellar glioma
    
  • Metastatic tumors
    
  • Lymphoma
    
  • Multiple sclerosis
    
  • Guillain–Barré syndrome
    
  • AIDS-related progressive multifocal leukoencephalopathy
    
  • Syringomyelia
    
  • Cervical spondylosis
    
• Chronic ataxia:
  
  • Alcohol-related cerebellar degeneration
    
  • Stable gliosis
    
  • Inherited disorders:
    
    • Spinocerebellar ataxias
      
    • Friedreich ataxia
      
    • Ataxia telangiectasia
      
    • Niemann–Pick disease
      
  • Hypothyroidism
    
  • Vitamin E deficiency
    
  • Tabes dorsalis
    
  • Congenital malformation:
    
    • Arnold—Chiari
      
    • Dandy–Walker
      
• Disease states that cause peripheral vertigo can mimic the gait findings in ataxia:
  
  • Benign paroxysmal positional vertigo
    
  • Acute labyrinthitis
    
  • Méniére disease
    

• May present with a refusal to walk
  
• Acute ataxia in children is usually a benign, self-limited process:
  
  • 60% of cases caused by acute cerebellar ataxia or drug ingestion
    
• Acute cerebellar ataxia:
  
  • Postinfectious cerebellar demyelination
    
  • Usually occurs in children 2–5 yr old
    
  • Onset 1–3 wk after triggering illness
    
  • Over 1/4 of cases occur after varicella, but linked to many viral infections and immunizations
    
  • Normal mental status
    
  • No fever, focal deficits, or seizures
    
  • Mild cases may be managed at home, but require injury prevention counseling
    
  • Most children recover completely within 3 mo without intervention
    
• Drug/toxic ingestions:
  
  • Expect mental status changes
    
  • Assess access to medications and order appropriate toxicological testing
    
• Guillain–Barré syndrome:
  
  • 15% present with sensory ataxia
    
  • Miller-Fisher variant: Clinical triad of ataxia, areflexia, and ophthalmoplegia
    
• Neoplasm:
  
  • More than 50% of childhood brain tumors occur in the brainstem or cerebellum
    
  • Opsoclonus-myoclonus-ataxia syndrome:
    
    • Paraneoplastic autoimmune syndrome affecting cerebellum
      
    • Over 50% due to neuroblastoma
      
• Stroke:
  
  • Rare in children, but can occur in patients with sickle cell disease or hypercoagulable states
    

• Gait disorders in the elderly are often multifactorial
  
• Underlying cognitive deficits may make it difficult to distinguish presyncope, weakness, vertigo, and incoordination
  
• Posterior circulation cerebrovascular syndromes, like VBI and stroke, are more common in the elderly and may present with vague symptoms, like dizziness
  
• Evaluate for signs of orthostasis or extrapyramidal disorders, like Parkinsonism
  

TREATMENT

• ABCs
  
• IV access
  
• Supplemental oxygen
  
• Cardiac monitor
  
• Fingerstick blood glucose:
  
  • Administer dextrose if hypoglycemic
    
  • Consider thiamine in alcoholics and malnourished patients
    

• Institute fall precautions
  
• Treatment must be tailored to the patient’s presentation and underlying pathology
  
• Cerebellar infarction can lead to significant edema with mass effect and herniation:
  
  • Neurosurgery consultation may be needed for decompressive craniectomy
    

• Dextrose: D
  ₅₀
  W 1 amp (50 mL or 25 g) (peds: D
  ₂₅
  W 2–4 mL/kg) IV
  
• Thiamine (vitamin B
  ₁
  ): 100 mg IV
  

FOLLOW-UP

• Acute and subacute ataxia, particularly if a benign etiology cannot be established
  
• Patients who cannot ambulate safely
  
• Admit patients with cerebellar hemorrhage or mass effect to the ICU
  

• Reversible or mild symptoms
  
• Normal mental status
  
• Able to ambulate safely
  

Follow up with primary care or neurology depending on likely etiology of symptoms

• Failure to distinguish true ataxia from other causes of gait instability
  
• Failure to note trauma in intoxicated patients
  
• Failure to realize the limitations of CT scan in evaluating the posterior fossa
  
• Failure to recognize the risk of herniation in cerebellar lesions, including stroke
  

• Friday JH. Ataxia. In: Fleisher GR, Ludwig S, Henretig FM, et al., eds.
  Textbook of Pediatric Emergency Medicine.
  5th ed. Philadelphia, PA: Lippincott Williams & Wilkins; 2006:189–192.
  
• Manto M, Marmalino D. Cerebellar ataxias.
  Curr Opin Neurol.
  2009;22:419–429.
  
• Mariotti C, Fancellu R, Di Donato S. An overview of the patient with ataxia.
  J Neurol.
  2005;252:511–518.
  
• Savitz SI, Caplan LR. Vertebrobasilar disease.
  N Engl J Med
  . 2005;352(25):2618–2626.
  

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