Dystonic Storm

Also known as Status Dystonicus is a rare life-threatening movement disorder emergency, characterized by marked exacerbations of dystonia that requires immediate intervention and ICU admission. It usually appears after weeks or months in the patients who have already been diagnosed with Dystonia and initial stabilization measures include intubation, mechanical ventilation, fluid resuscitation, antibiotics, nasogastric or parenteral nutrition, and antipyretics.

Introduction

  • Also known as Status Dystonicus
  • A rare life-threatening movement disorder emergency, characterized by marked exacerbations of dystonia that requires immediate intervention and ICU admission

Clinical Features

  • It usually occurs in patients with severe or poorly controlled dystonia.
  • In addition to the development of increasingly frequent and severe episodes of generalized dystonia, signs, and symptoms of Dystonic Storm are included in Table 1.

Signs and Symptoms of Dystonic Storm

  • Fever
  • Tachypnea
  • Sweating
  • Dysarthria
  • Respiratory failure
  • Tachycardia
  • Hypertension
  • Autonomic instability
  • Dysphagia
  • Pain

Lab Findings

Leukocytosis
High C-reactive protein
Elevated serum CK
Myoglobinemia

Differential Diagnosis

  • There are several conditions which present with fever, elevated serum CK, with or without muscle rigidity and thus resembling Dystonic Storm.
  • As compared to other conditions, dystonic storm is usually present in the pediatric population and develops quickly over hours to several days. Triggers may or may not be present.

Table 3: Differential Diagnosis of Dystonic Storm

Differential Diagnosis of Dystonic Storm
Entity
Time course
Movement disorder phenomenology
Other Neuro Signs
Altered Mental Status
Autonomic instability
Hours-Days
Dystonia +/− chorea
-
-
+
Hours-Days
Chorea
-
-
-
Acute
Dystonia
Oculogyria
-
+/-
Days-Weeks
Parkinsonism
-
+
+
Hours-Days
Myoclonus
-
+
+
Hours-Days
Parkinsonism
-
+
+
Acute
-
Psychosis
+
+/-
Acute
Myoclonus
Psychosis
+
+
Days-Weeks
Myoclonus
Psychosis
+
+
 

Triggers and Clinical Course Triggers

Triggers

  • Dystonic Storm is usually triggered, however, one-third of events are unprovoked.
  • The main triggers are infection and change in medication (Table 4)
  • Less common triggers are trauma, surgical procedures, anaesthesia, ‘metabolic disorder’ decompensation, stress, pain, gastro-oesophageal reflux disease, constipation, and puberty-related deterioration in Cerebral Palsy.
🤦‍♀️
Triggers of Dystonic Storm -Medication Change
ITB withdrawal
Reduction/withdrawal of other dystonia medications
Initiation of D-penicillamine or Zinc in Wilson Disease
Introduction of Clonazepam
Zolpidem discontinuation in Parkinson’s disease

Clinical Course of Dystonic Storm

  • Dystonic Storm usually appears after weeks or months in the patients who have already been diagnosed with Dystonia
  • In some patients, a prodrome of status dystonicus may be present where dystonia is worse than baseline but has not become as severe as in true storm (Figure 1)
  • The true storm usually lasts 2-4 weeks with slow recovery
  • The mortality is 10% even with treatment
  • Some patients are prone to relapses and patients with a history of Dystonic Storm should be monitored for recurrence

Figure 1: Typical Clinical Course of Dystonic Storm Patient

 
notion image
Source: Termsarasab, Pichet, and Steven J. Frucht. “Dystonic Storm: A Practical Clinical and Video Review.” Journal of clinical movement disorders 4 (2017): 10. Web. https://clinicalmovementdisorders.biomedcentral.com/articles/10.1186/s40734-017-0057-z

Management

  • Management must be initiated immediately
  • Patients should be admitted to ICU
  • The initial stabilization measures include intubation, mechanical ventilation, fluid resuscitation, antibiotics, nasogastric or parenteral nutrition and antipyretics

Management in first 24 hours

  • Goal during the first 24 hours
    • Identify and treat triggers such as infection or medications
    • Evaluate if the patient requires Globus Pallidus Interna (GPi) Deep Brain Stimulation or ITB therapy (Figure 2)

Management in 2-4 weeks

  • The usual list of medical treatment for the next 2-4 weeks is listed in table 5
  • The anti-dystonic drugs are used in combination
    • Most successful combination include an anticholinergic (trihexyphenidyl), a dopamine blocker (haloperidol or pimozide), and tetrabenazine

Table 5: Management in next 2-4 weeks

Management in next 2-4 weeks
Dystonic Specific treatment
Supportive Treatment
Ist line: IV midazolam
2nd Line: Propofol
3rd Line: Non-depolarizing neuromuscular blockers or Barbiturates
Source: Termsarasab, Pichet, and Steven J. Frucht. “Dystonic Storm: A Practical Clinical and Video Review.” Journal of clinical movement disorders 4 (2017): 10. Web. https://clinicalmovementdisorders.biomedcentral.com/articles/10.1186/s40734-017-0057-z

Supportive Treatment

  • Includes airway protection, sedation and pain control
  • Anesthetic agents such as IV midazolam is generally chosen as a first choice i.e. because of its muscle relaxant effect, rapid onset of action, and short half-life
  • For refractory symptoms, propofol is considered as a second line
  • Third line agents are pancuronium and barbiturates which are non-depolarizing paralytic agents.
  • To prevent dependence or tolerance, attempts to reduce sedative and anesthetics drugs should be made

Invasive therapies

Intrathecal baclofen

  • ITB has been used in some patients with refractory status dystonicus
  • The risks of using ITB are over-dosage, withdrawal syndrome and migration or breakage of catheter

Deep brain stimulation

  • In majority of patients DBS has been an effective treatment
  • The anatomical site of choice is globus pallidus interna (bilaterally)
  • The effects are usually evident within days or weeks
  • It is however challenging to operate on patients with status dystonicus due to higher rate of hardware and other complications present in these patients
 

Pallidotomy and thalamotomy

  • Pallidotomy is rarely used unless DBS is not available

Figure 2: Management in first 24 hours

notion image
Source: Termsarasab, Pichet, and Steven J. Frucht. “Dystonic Storm: A Practical Clinical and Video Review.” Journal of clinical movement disorders 4 (2017): 10. Web. https://clinicalmovementdisorders.biomedcentral.com/articles/10.1186/s40734-017-0057-z

Complications

  • Respiratory compromise/failure, rhabdomyolysis and acute renal failure due to severe generalized muscle spasms
  • Secondary complications include dysphagia, thrombosis, injuries, fractures and sepsis

Further Reading

Termsarasab, P., & Frucht, S. J. (2017). Dystonic storm: a practical clinical and video review. Journal of Clinical Movement Disorders, 4, 10. https://doi.org/10.1186/s40734-017-0057-z

References

  • Termsarasab, P., & Frucht, S. J. (2017). Dystonic storm: A practical clinical and video review. Journal of Clinical Movement Disorders, 4(1). https://doi.org/10.1186/s40734-017-0057-z
  • Allen, N. M., Lin, J.-P., Lynch, T., & King, M. D. (2013). Status dystonicus: A practice guide. Developmental Medicine & Child Neurology, 56(2), 105–112. https://doi.org/10.1111/dmcn.12339
  • R, H. (2021). Intermittent cerebral ischemia as a cause of dystonic storms in hypermobile Ehlers-Danlos syndrome with upper cervical instability, and Prolotherapy as successful treatment: 4 case series. Clinical and Medical Case Reports, 7(07).
  • Mayo Foundation for Medical Education and Research. (2020, April 25). Dystonia. Mayo Clinic.https://www.mayoclinic.org/diseases-conditions/dystonia/symptoms-causes/syc-20350480.