We report a case of fulminant sepsis 10 years after posttraumatic splenectomy. The low-cardiac-output stage of the septic shock with disseminated intravascular coagulation (DIC), which was already marked on admission to the intensive care unit, could not be overcome despite appropriate shock treatment. The pathogenetic spectrum includes more than 70% pneumococci, but any pathogen can trigger an overwhelming postsplenectomy infection (OPSI) syndrome. Pathogenetically, the OPSI syndrome is primarily due to distinctly reduced bacterial clearance from loss of the reticuloendothelial tissue in the spleen. Appropriate treatment of the septic shock is of prime therapeutic importance. In summary, the following recommendations can be made: 1. Nonspecific symptoms of infection in splenectomized patients, such as fever, call for immediate clarification with respect to the onset of a septic process. Immediate admission to a hospital, close monitoring, including blood cultures, and immediate antibiotic therapy are unavoidable. 2. The aim of treatment is to prevent DIC by aggressive therapy of the septic shock with prevention of the low-output stage. 3. Splenectomized patients must be informed of the possibility of a serious, potentially fatal infection and its premonitory symptoms. An emergency passport is appropriate. 4. In view of the few side effects of the vaccine, all splenectomized patients should be immunized against pneumococci. Children under 2 years of age should furthermore receive prophylactic oral penicillin up to the age of 5.