Hyperammonemic encephalopathy in a pediatric patient with Salmonella enteritis and after Roux-en-Y surgery

Wu, Yen-Hsien; Chen, I-Chen; Lin, Jao-Yu; Dai, Zen-Kong

At 1 year 3 months of age, she was brought to our emergency department for fever, severe diarrhea, and abdominal distension. On arrival, her consciousness was clear. Her body temperature was 40 C, heart rate was 132 beats per minute, and blood pressure was 111/37 mm Hg. Her white blood cell count was 14 000/μL, and the C-reactive protein level was 221 mg/L. Her liver function tests (albu- The specific mechanism underlying hyperammonemia after Rouxen-Y surgery remains unknown; however, some possible mechanisms have been identified. First, partial ornithine transcarbamylase deficiency after Roux-en-Y gastric bypass surgery has been proposed, which leads to impairment of the urea cycle, which in turn results in serum ammonia accumulation. Second, changes in the intestinal flora, which lead to increased ammonia production after the surgery, have also been proposed. Third, a catabolic state accelerating protein breakdown may also contribute to hyperammonemia. 1 In our case, hyperammonemia occurred 9 months after the Roux-en-Y surgery;