Non hepatic hyperammonaemia: a case series

<h3></h3> Hyperammonaemia is a reversible cause of encephalopathy and can mimic of several neurological conditions. The diagnosis may be delayed, particularly if liver function tests are normal. We present a case series of adult non-hepatic hyperammonaemia patients highlighting the importance of testing ammonia levels in patients with cryptogenic neurological disease and the consideration of multiple causes including iatrogenic elevation secondary to sodium valproate, gastrointestinal and urinary causes of hyperammonaemia. None had a urea cycle disorder, as such there is little evidence on how best to manage these patients. We summarise the treatments used in these cases and the patient’s outcome.