Hyperammonemic
encephalopathy is rarely caused by a
urinary diversion. We herein experienced a case of rectal
carcinoma with rectovesical and ileal fistulae that developed hyperammonemic
encephalopathy. A 72-year-old man suffered from a
fever,
diarrhea, pneumaturia, and fecaluria beginning in April 2013 and was referred to our hospital in May 2013. He developed a
loss of consciousness and whole body cramping on the first hospital day. The laboratory data indicated an inflammatory reaction and
hyperammonemia with a highly elevated serum
ammonia (NH3) level of 703 μg/dl. The patient was diagnosed to have rectal
carcinoma with rectovesical and ileal fistulae according to computed tomography (CT) and a water-soluble contrast
enema. We administered a
solution of
branched chain amino acids (BCAA) and
antibiotics. Furthermore, we repeatedly irrigated bladder through the
urethral catheter. The patient's symptoms recovered, and the serum
ammonia levels on the second and third hospital day were decreased to 210 and 135 μg/dl, respectively. However, the symptoms of
infection and
confusion were suspected to repeat; we elected to perform surgical treatment. An ileal disconnection with ileocecal bypass and sigmoidostomy were effective for preventing hyperammonemic
encephalopathy.