We report a case of a 56-year-old man with a history of splenectomy for idiopathic thrombocytopenic purpura who developed persistent bacteremia in the acute phase of human bartonellosis. This patient did not develop hemolytic anemia. Only after several courses of antibiotic treatment was the infection eradicated. This is an unusual case of overwhelming post-splenectomy infection by Bartonella bacilliformis, which provides clinical evidence that the spleen is a critical effector organ of clearance of this infection as well as the effector organ of bartonellosis-associated hemolytic anemia.