Magnetic resonance spectroscopy allows the assessment of several metabolites in brain tissue. In patients with hepatic encephalopathy, this technique shows a rise in glutamine and a decrease in myoinositol in brain tissue. However, the role of magnetic resonance spectroscopy in the diagnosis of hepatic encephalopathy is not known. We report the case of a patient with a relapsing confusional syndrome who underwent magnetic resonance spectroscopy. Previously, hepatic encephalopathy was ruled out because of the negative results of a transjugular liver biopsy and normal hepatic venous pressure gradient. The results of magnetic resonance were characteristic of hepatic encephalopathy. Abdominal computed tomography demonstrated large portosystemic shunts associated with cirrhosis of the liver. This case shows that magnetic resonance spectroscopy is an useful technique for the diagnosis of hepatic encephalopathy in selected cases, such as those without clinical signs of cirrhosis and/or large portosystemic shunts.