Recommendations for the Diagnosis and Therapeutic Management of Hyperammonaemia in Paediatric and Adult Patients

Area of Science:

• Metabolic disorders
• Clinical medicine
• Nephrology

Background:

• Hyperammonaemia is a serious metabolic derangement potentially causing severe neurological damage and death.
• It is rare in children, often linked to inborn errors of metabolism, but common in adults due to diverse causes like liver disease, infections, and dehydration.
• In older patients, hyperammonaemia is frequently overlooked or underestimated.

Purpose of the Study:

• To provide an updated clinical protocol for managing hyperammonaemia across all age groups.
• To assist clinicians, particularly those with limited experience, in normalizing ammonia levels.
• To emphasize timely interventions and monitoring for effective treatment.

Main Methods:

• Review of recent publications by a panel of experts.
• Emphasis on frequent monitoring of ammonia levels to assess treatment response.
• Integration of nutritional measures, including protein restriction and adequate caloric intake.
• Guidelines for initiating pharmacological therapies and extrarenal clearance measures, such as hemodialysis.

Main Results:

• Proposes specific ammonia level thresholds for initiating hemodialysis: >200–350 µmol/L in children up to 18 months and >150–200 µmol/L in older individuals.
• Highlights the importance of avoiding delays in treatment, especially regarding dialysis.
• Stresses the need for adequate caloric intake alongside protein restriction in nutritional management.

Conclusions:

• Effective management of hyperammonaemia requires a comprehensive approach including monitoring, nutrition, and timely pharmacological and extrarenal clearance therapies.
• Early and decisive intervention, particularly with hemodialysis at defined ammonia levels, is crucial for preventing severe neurological complications.
• This protocol serves as a guide for clinicians to manage hyperammonaemia effectively in patients of all ages.