A patient with a stage IV high-grade non-Hodgkin's lymphoma who developed a fatal hemophagocytic syndrome is presented: When the patient had achieved complete remission and receiving fludarabine and chlorambucil/prednisone, she developed miliary tuberculosis, the CD4+ T-cell count then being 50/microL; the hemophagocytic syndrome ensuing at this point was fatal. Speculations about the predisposing factors that could have led to this complication are discussed focusing on the severe cellular immunosuppression which developed probably related to the use of fludafabine: it could be useful in the future to use anti-tuberculous prophylaxis in selected patients treated with this purine nucleoside analog.