An unusual case of hyperammonemia in a 83-year-old woman

Hyperammonemia, with confusion and lethargy, developed in a 83-year-old woman during a urinary tract infection by Morganella morganii, a urea-splitting Gram-negative bacillus. In this patient, it is thought to have resulted from the production of excessive amounts of ammonia due to bacterial urease and its subsequent reabsorption into systemic circulation. The patient was treated with specific antibiotic therapy, with resolution of the urinary tract infection, progressive reduction in ammonia blood levels, and a parallel improvement in her consciousness and cognitive status.