Phenytoin-induced chronic liver enzyme elevation and hepatic fibrosis: A case report

Liver fibrosis results from chronic damage to the liver. Advanced liver fibrosis results in cirrhosis, liver failure, and portal hypertension and may even require liver transplantation. A liver biopsy is considered the "gold standard" method for the assessment of liver fibrosis; however, ultrasonography can also detect changes in the hepatic parenchyma due to fibrosis. Although reports in the literature describe phenytoin-induced hepatic injury, often this rare occurrence is usually accompanied by a hypersensitivity reaction.

Our patient is a 50-year-old female with history of schizoaffective disorder, bipolar type, who had been admitted to a state psychiatric facility. She has a history of seizure disorder, which had been well controlled with phenytoin since 2011. Mild-to-moderate elevations in her liver enzymes were noted during therapy but normalized once phenytoin was discontinued. An ultrasound of the patient's liver in January 2016 showed changes of fatty infiltration and fibrosis.

This case differs from other cases reported in the literature that describe phenytoin-induced hepatic injury. The majority of these cases are accompanied by immune-allergic features. To our knowledge, there have been no reported cases in the literature of prolonged liver enzyme elevation resulting in phenytoin-induced hepatic fibrosis.