What causes drop attacks (sudden loss of muscle tone) in pediatric patients?

From the Guidelines

Drop attacks in pediatric patients are often caused by underlying neurological or cardiac conditions, such as epilepsy, particularly benign epilepsy with centrotemporal spikes, or cardiogenic syncope due to prolonged QT interval 1.

Common Causes

• Epilepsy: Atonic seizures can cause drop attacks in children 1
• Cardiogenic syncope: Due to prolonged QT interval, can cause drop attacks in pediatric patients 1
• Reflex syncope: Represents the vast majority of the etiology of syncope in pediatric patients, but in rare cases, syncope is the manifestation of life-threatening cardiac arrhythmia or structural abnormalities 1

Diagnostic Evaluation

A comprehensive diagnostic evaluation is necessary to determine the underlying cause of drop attacks in pediatric patients, including:

• Detailed medical history: To identify potential triggers and underlying conditions 1
• Physical examination: To identify any signs of underlying conditions 1
• Family history: To identify any genetic predispositions to cardiac conditions 1
• 12-lead ECG: To identify any cardiac abnormalities 1

Other Potential Causes

In some cases, drop attacks may also be triggered by:

• Orthostatic hypotension: A drop in blood pressure upon standing, which can cause dizziness and fainting 1
• Dehydration: Can cause dizziness and fainting, particularly in pediatric patients 1
• Anemia: Can cause dizziness and fainting due to a lack of red blood cells or hemoglobin 1 It is essential to conduct a thorough diagnostic evaluation to determine the underlying cause of drop attacks in pediatric patients and provide appropriate treatment and management 1.

From the FDA Drug Label

The primary measures of effectiveness were the percent reduction in drop attacks and a parental global rating of seizure severity The FDA drug label does not answer the question.

From the Research

Causes of Drop Attacks in Pediatric Patients

• Drop attacks in children can be caused by various factors, including:
  • Severe epilepsies, as seen in symptomatic epilepsy of early childhood 2
  • Movement disorders, such as benign hereditary chorea (BHC) caused by TITF1 gene mutations 3
  • Cataplexy, which can occur in isolation without narcolepsy 4
  • Psychiatric disorders

Specific Conditions Associated with Drop Attacks

• Benign hereditary chorea (BHC): characterized by mild neuromotor delay and sudden falls, often associated with subtle choreiform movements 3
• Symptomatic epilepsy of early childhood: drop attacks can be caused by epileptic spasms, atonic seizures, or myoclonic-atonic seizures 2
• Isolated cataplexy: a rare condition that can cause drop attacks without associated narcolepsy 4

Diagnostic Considerations

• A thorough clinical and laboratory investigation is necessary to determine the underlying cause of drop attacks in pediatric patients 3, 5
• The presence of neuromotor delay, choreiform movements, or other specific symptoms can help guide the diagnosis 3, 2
• In some cases, drop attacks may be caused by underlying cardiac or vestibular disorders, which require further investigation 5, 6