From the Guidelines
Asterixis in children is a clinical sign characterized by a flapping tremor of the hands, often indicative of metabolic or hepatic encephalopathy 1.
Key Points
- In pediatric patients, asterixis is typically managed by addressing the underlying cause, such as correcting electrolyte imbalances or treating liver disease.
- Medications such as lactulose (1-2 mL/kg/day, divided into 3-4 doses) or rifaximin (10-20 mg/kg/day, divided into 2 doses) may be used to reduce ammonia levels and alleviate symptoms, with treatment duration depending on the underlying condition 1.
- Close monitoring of the child's neurological status and adjustment of medication dosages as needed is crucial to prevent complications.
- Asterixis is not pathognomonic of hepatic encephalopathy, as it can be observed in other diseases, such as uremia 1.
Differential Diagnosis
- The differential diagnosis of asterixis includes metabolic encephalopathy, hydroelectrolytic disorders, and focal brain lesions 1.
- A clinical and paraclinical diagnostic work-up, including blood tests and brain imaging, is essential to exclude a differential or associated diagnosis 1.
- The presence of asterixis is strongly suggestive of metabolic encephalopathy, and its diagnosis should be considered in the context of the child's overall clinical presentation 1.
From the Research
Significance of Asterixis in a Child
Asterixis, also known as flapping tremor, is a subtype of negative myoclonus characterized by brief, arrhythmic lapses of sustained posture due to involuntary pauses in muscle contraction 2. The significance of asterixis in a child can be understood by considering the following points:
- Asterixis is not specific to any pathophysiological process, but it is more commonly reported in hepatic encephalopathy, renal and respiratory failure, cerebrovascular diseases, as well as associated with drugs that could potentially lead to hyperammonemia 2.
- Asterixis is usually asymptomatic and not spontaneously reported by patients, highlighting the importance of actively searching for this sign in the physical exam of encephalopathic patients because it could indicate an underlying toxic or metabolic cause 2.
- The detection of asterixis can be crucial in differentiating between hepatic encephalopathy and other conditions, such as delirium tremens, and can aid in the diagnosis and management of these conditions 3.
- The pathophysiology of asterixis is not fully understood, but studies suggest that it may be associated with cortical activation in the primary motor cortex 4.
- Asterixis has a rich history and its significance as a tool for the evaluation and prognosis of encephalopathies has been suggested 5.
Clinical Implications
The clinical implications of asterixis in a child can be significant, and may include:
- Indication of an underlying neurological or metabolic disorder, such as hepatic encephalopathy or renal failure 6, 2.
- Aid in the diagnosis and differentiation of various encephalopathies, such as hepatic encephalopathy and delirium tremens 3.
- Importance of actively searching for asterixis in the physical exam of encephalopathic patients, as it may not be spontaneously reported by patients 2.
- Potential association with cortical activation in the primary motor cortex, which may have implications for the understanding and management of asterixis 4.