Clinical signs and symptoms of hyperammonemia are mainly neurological in origin. Yet symptoms are generally nonspecific and may suggest several diagnostic pathways. Given the potential risk of brain injury or death due to hyperammonemia, it’s critical to suspect and test for the condition—especially with any unexplained alteration in consciousness or encephalopathy.1
Be aware of the signs and symptoms of hyperammonemia. Learn about caregivers’ and patients’ experiences that underscore the importance of suspecting and testing for hyperammonemia.
HYPERAMMONEMIA SYMPTOMS VIDEO
Although there is some overlap, hyperammonemia symptoms can differ depending on the patient's age:
Learn more about recognizing hyperammonemia symptoms and triggers.
The underlying causes of hyperammonemia can be diverse. Some of the more common causes include2:
Hepatocyte destruction and reduced urea cycle enzyme function
E.g., inhibition of the urea cycle by valproic acid
Release of ammonia from red blood cells
Increased ammonia generation due to microbial catabolism of hemoglobin
Regardless of the cause, hyperammonemia can be toxic to the central nervous system. Awareness is the first step to preventing possible
irreversible brain damage or death.
Hyperammonemia can be caused by many diseases and disorders. In patients who have an underlying metabolic disorder, medical events or other stressors can trigger a hyperammonemic crisis. This can occur in patients with milder disorders who have been functioning relatively normally—sometimes for decades.5
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11. N-acetylglutamate synthetase deficiency. National Organization for Rare Disorders. 2016. Available at: https://rarediseases.org/rare-diseases/n-acetylglutamate-synthetase-deficiency. Accessed September 11, 2017.
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