Diverting the Diagnosis: A Case Report of Hemodialysis Masking the Etiology of Hyperammonemia

This case illustrates the challenges of determining the etiology of hyperammonemia in patients treated with hemodialysis due to the dialysis clearance of ammonia. Portosystemic shunts cause hyperammonemia by bypassing the liver's ammonia-detoxification pathways, and their effects may be paradoxically exacerbated immediately after dialysis due to dialysis-related hemodynamic changes. We emphasize the importance of investigating hyperammonemia as a cause of altered level of consciousness among patients being treated with hemodialysis and considering anatomical shunting in the differential diagnosis.