Grundsätzliche und praktische Aspekte zur Hyperammonämie im Kindesalter

Zusammenfassung

Eine Hyperammonämie kann grundsätzlich in jedem Lebensalter auftreten und kann zu jedem Zeitpunkt lebensbedrohlich sein. Im Kindesalter liegt einer Hyperammonämie meist eine angeborene Stoffwechselkrankheit zugrunde.

Klinisches Leitsymptom sind Appetitverlust und Bewusstseinsstörungen. Bei anhaltend hohen Ammoniakkonzentrationen droht die Entwicklung eines Hirnödems mit schlechter Prognose für Heilung oder überleben.

Im Notfall ist die sofortige Einleitung von Diagnostik und Therapie entscheidend. Jede zeitliche Verzögerung kann für den Patienten fatale Folgen haben. Es muss sichergestellt sein, dass die Proben in ein spezialisiertes Labor versandt werden, in dem Diagnostik und Befundübermittlung innerhalb weniger Stunden gewährleistet sind.

Es existieren diätetische und medikamentöse Möglichkeiten, den Stickstoffpool im Organismus zu reduzieren, um die ansonsten unausweichliche Neurotoxizität von Ammoniak zu verhindern. Als ultima ratio sind frühzeitig extrakorporale Verfahren der Gifteliminierung zu erwägen.

Summary

Hyperammonemia can affect patients of every age group and can always result in a life threatening metabolic decompensation. In most pediatric patients, inborn errors of metabolism are the underlying disorder in states of hyperammonemia.

Clinically, patients of all age groups present with loss of appetite and neurological symptoms ranging from mild and unspecific symptoms to coma. If hyperammonemia persists, cerebral edema with a poor prognosis might occur. Therefore, the prompt initiation of both thorough diagnostics and start of therapy is of utmost importance. This should best be guided by pediatric metabolic specialists. All biochemical results should be interpreted and communicated within less than a day.

Therapeutic measures comprise a range of dietetic and medical options and always aim at a protein-anabolic situation in the patient and at a reduction of the surplus nitrogen. Extracorporeal detoxification must be considered in patients with high levels of hyperammonemia.

Schlüsselwörter

Hyperammonämie - Stoffwechselstörung - Notfall

Keywords

Hyperammonemia - errors of metabolism - emergency

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