AbstractPostsplenectomy vulnerability to infection is not limited to age or disease process. Postsplenectomy infection is an emergency problem that requires immediate and accurate treatment because death is potential within a few hours of onset. Although the pathogenesis of overwhelming postsplenectomy sepsis is not completely understood, experimental evidence suggests that loss of mechanical filtration is more important than immunologic deficiences resulting from splenectomy. Certainly, a combination of both may be present. While no single measure seems to completely protect against overwhelming postsplenectomy sepsis, experimental evidence suggests that by reducing or minimizing the amount of spleen removed by newer surgical techniques, and by the addition of pneumococcal vaccine and prophylactic penicillin, the incidence of overwhelming sepsis can be reduced. Further evaluation of splenic function is necessary to assess the role of autotransplantation in the prevention of postsplenectomy sepsis (Fig. 1).