Alteración de la marcha en un paciente post-trasplante hepático

posttransplant lymphoproliferative disorder (ptld) represents a relatively frequent complication in solid organ or stem cell transplantation recipients. this entity encompasses a wide spectrum of lesions, those that exhibit early benign histological changes and those characterized by malignant behavior, showing diverse response to current therapeutic options. even though these lesions can grow in multiple sites, central nervous system (cns) localization has been described in up to 22% of cases and as primary lesions in 12%; usually pltd in cns is correlated with poor prognosis. standard diagnostic and therapeutic strategies have not been clearly defined, mainly because of blood-brain barrier function. as a consequence, high dose methotrexate has been used in a similar way as in primary central nervous system lymphoma cases; additionally, new strategies such as intravenous rituximab have been reported. we describe the case of a 76 year-old liver transplant recipient who presents with gait disturbance due to a brain tumor lesion. stereotactic biopsy was performed and cns ptld was diagnosed. after initial immunosuppression reduction and five cycles of high dose of rituximab plus methotrexate therapy, a very good partial response was achieved.