Postoperative hyperammonemic encephalopathy due to unexpected constipation in a patient with hyperornithinemia-hyperammonemia-homocitrullinuria syndrome: a case report

Hyperornithinemia-hyperammonemia-homocitrullinuria (HHH) syndrome is a rare autosomal recessive urea cycle disorder associated with a high risk of exacerbation of hyperammonemia during the perioperative period. Here, we describe an adult patient with HHH syndrome who developed hyperammonemic encephalopathy secondary to postoperative constipation.