Trombosis venosa portal e hiperplasia nodular regenerativa hepática; posible efecto adverso asociado a bevacizumab y oxaliplatino / Portal vein thrombosis and nodular regenerative hyperplasia associated with the use of bevacizumab and oxaliplatin. Report of one case

Nodular regenerative hyperplasia (NRH) consists in diffuse transformation of the hepatic parenchyma into small regenerative nodules without fibrosis, secondary to vascular occlusion and flow alterations. This gives a nodular appearance to theliver, as there is atrophy and compensatory hypertrophy of hepatocytes. We reporta 69-year-old male who suffered of colon cancer and was treated with Oxaliplatin (OX) and Bevacizumab (B). During treatment with B the patient presented a partial thrombosis of the portal vein, that one year later became permeable. Esophageal varices were found in an upper digestive endoscopy. Hepatic tests were normal. Aliver biopsy was performed and informed nodular regenerative hyperplasia. Thus, the different factors that could explain this pathology are analyzed. B, a monoclonal antibody against vascular endothelial growth factor, reduces the anti-apoptotic, anti-inflammatory and survival effects produced by this factor, affecting the vascular protection of the endothelial cell. On the other hand, OX activates metalloproteinasesand depletes sinusoidal glutathione producing sinusoidal lesions. Thus, (OX) would be associated with sinusoidal obstruction and NRH sporadically. It is important to discuss the possible etiologic factors that can cause NRH reviewing the hepatotoxic effects caused by both drugs.

Hiperplasia nodular regenerativa del hígado secundaria a uso de azatioprina por trasplante renal previo, tratado con trasplante combinado hepático y renal / Combined hepatic and renal transplant after nodular regenerative hyperplasia of the liver secondary to azathioprine in renal transplant patient

Nodular regenerative hyperplasia is an uncommon condition, characterized by the presence of regenerative nodules with minimal or absence of fibrosis, which can lead to non-cirrhotic portal hypertension. There are numerous diseases, conditions and drugs that can cause it. Thiopurines, a group of immunosuppressors used in transplanted patients, has been linked to this entity. We report a case of a renal transplant woman, who has been on chronic therapy with azathioprine and that develops portal hypertension and end-stage renal disease, undergoing combined hepatic and renal transplant. Histological examination of the explanted liver was compatible with nodular regenerative hyperplasia. How azathioprine causes this entity is unknown, but endothelial vascular damage in a dose-dependent manner is postulated as the main mechanism. To our knowledge, this is the first case report of a renal transplant patient who develops nodular regenerative hyperplasia of the liver in association with azathioprine, and undergoes combined hepatic and renal transplant, with a favorable outcome 5 years post procedure.

La hiperplasia nodular regenerativa es una entidad infrecuente, que se caracteriza por la presencia de nódulos hepáticos con ausencia o mínima fibrosis y que puede llevar a hipertensión portal de origen no cirrótico. Existen diversas enfermedades, condiciones y medicamentos que la causan, destacando entre estos últimos las tiopurinas, inmunosupresores utilizados habitualmente en trasplantados. Se presenta el caso de una paciente trasplantada renal usuaria crónica de azatioprina, que desarrolla hipertensión portal además de deterioro de la función renal, requiriendo de un doble trasplante hepático y renal, destacando en la biopsia del explante hallazgos histológicos compatibles con hiperplasia nodular regenerativa. Los mecanismos de daño por azatioprina en esta entidad son desconocidos, pero se postula al daño endotelial dosis-dependiente como principal causa. La revisión de la literatura demuestra que este caso corresponde al primero de hiperplasia nodular regenerativa secundaria a azatioprina en trasplantado renal, que requiere de doble trasplante hepático y renal con evolución favorable hasta 5 años post trasplante.

Drug induced hepatic focal nodular hyperplasia.

Focal nodular hyperplasia, an uncommon benign hepatic tumor, has been reported following ingestion of various drugs and chemical agents. The authors report a case of a young girl who developed such lesion following ingestion of anti-tuberculosis drugs for the treatment of her abdominal tuberculosis.