Basics
Description
- Inability to perform coordinated movements
- Caused by a disorder of the cerebellum or its connections:
- Ipsilateral signs with lateral cerebellar lesions
- Truncal ataxia with midline lesions
Etiology
Usually cerebellar in origin, but may occur with sensory, motor, or vestibular dysfunction:
- Trauma
- Mass lesions
- Vascular disorders
- Infections or postinfectious processes
- Toxins/drugs
- Metabolic/endocrine derangements
- Demyelinating diseases
- Congenital malformations
- Hereditary disorders:
- Inborn errors of metabolism
- Progressive degenerative ataxias
- Nutritional deficiencies
Diagnosis
Signs and Symptoms
- Gait disturbance:
- Ataxia often presents with unsteady gait
- Initial sense of insecurity while walking
- Problems with special skills (bicycling, skiing, climbing)
- Sense of imbalance
- Wide base stance and staggering gait
- Test tandem gait to identify subtle ataxia
- Limb ataxia:
- Incoordination
- Intention tremors
- Clumsiness with writing, picking up objects, buttoning
- Dysmetria: Under- or overshooting on finger-to-nose and heel-to-shin testing
- Dysdiadochokinesis: Difficulty with rapid alternating movements
- Truncal ataxia:
- Head tremors
- Truncal instability
- Titubation: Swaying of the head/trunk while at rest
- Dysarthria and bulbar symptoms:
- Slurred speech
- Staccato, scanning speech
- Choking from incoordination of swallowing
- Visual abnormalities:
- Blurry vision
- Vertigo:
- Distinguish central from peripheral vertigo
- Peripheral vertigo is often severe, triggered by movement, and may be accompanied by ear pain, hearing loss, or tinnitus
- Nystagmus:
- Gaze-evoked nystagmus: Repetitive drifts to the midline followed by fast phase to the eccentric side
- Rebound nystagmus
- Abnormalities of muscle tone and strength:
- Isometrataxia: Difficulty sustaining constant force during hand use:
- Ask patient to hold slight, steady pinching pressure against examiners finger (examiner will feel irregular pressure)
- True muscle weakness or hypotonia uncommon in cerebellar disease
- Sensory ataxia:
- Paresthesias
- Numbness
- Cautious, steppage gait
- Marked worsening of coordination with eyes closed:
- A positive Romberg sign is the classic finding in sensory ataxia
- Loss of position/vibration sense
- Difficulty with fine motor skills
History
- 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
Physical Exam
- 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
Essential Workup
A detailed history and physical exam will help determine which tests are necessary
Diagnosis Tests & Interpretation
Lab
- 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
Imaging
- 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
Diagnostic Procedures/Surgery
- Lumbar puncture:
- Indicated if infection or Guillain-Barr © suspected
Differential Diagnosis
- 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 B1 or B12 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-Barr © 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
- M ©ni ©re 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-Barr © 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
Pre-Hospital
- Acute onset of ataxia may be due to stroke or hemorrhage
- Deterioration in mental status may warrant field endotracheal intubation
Initial Stabilization/Therapy
- ABCs
- IV access
- Supplemental oxygen
- Cardiac monitor
- Fingerstick blood glucose:
- Administer dextrose if hypoglycemic
- Consider thiamine in alcoholics and malnourished patients
Ed Treatment/Procedures
- Institute fall precautions
- Treatment must be tailored to the patients presentation and underlying pathology
- Cerebellar infarction can lead to significant edema with mass effect and herniation:
- Neurosurgery consultation may be needed for decompressive craniectomy
Medication
- Dextrose: D50W 1 amp (50 mL or 25 g) (peds: D25W 2-4 mL/kg) IV
- Thiamine (vitamin B1): 100 mg IV
Follow-Up
Disposition
Admission Criteria
- 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
Discharge Criteria
- Reversible or mild symptoms
- Normal mental status
- Able to ambulate safely
Followup Recommendations
Follow up with primary care or neurology depending on likely etiology of symptoms
Pearls and Pitfalls
- 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
Additional Reading
- 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.
Codes
ICD9
- 334.2 Primary cerebellar degeneration
- 334.3 Other cerebellar ataxia
- 781.3 Lack of coordination
- 334.0 Friedreichs ataxia
ICD10
- G11.1 Early-onset cerebellar ataxia
- G11.9 Hereditary ataxia, unspecified
- R27.0 Ataxia, unspecified
- R26.0 Ataxic gait
SNOMED
- 20262006 Ataxia (finding)
- 250067008 Truncal ataxia (finding)
- 230227009 Early onset cerebellar ataxia (disorder)
- 10394003 Friedreichs ataxia (disorder)