[Nodular regenerative hyperplasia: azathioprine-induced hepatotoxicity in a patient with Crohn's disease]. / Hiperplasia nodular regenerativa: hepatotoxicidad por azatioprina en un paciente con enfermedad de Crohn.

We report the case of a 53-year-old man with Crohn's disease who developed azathioprine-induced nodular regenerative hyperplasia of the liver. The diagnosis was suspected when abnormalities in liver function tests were observed and transabdominal ultrasonography and upper gastrointestinal endoscopy showed signs of portal hypertension. The final diagnosis was established by liver biopsy, showing the characteristic alterations in liver architecture. Outcome was favorable after treatment discontinuation, with complete normalization of liver function tests within a year. The present article describes the incidence and the main clinical characteristics of this adverse effect to thiopurines.