The paper describes the case of a 28-year-old patient without a spleen in whom high fever, vomiting, abdominal cramps, palpable purpura and peripheral cyanosis suddenly developed. Upon admission, he was in septic shock with multi-organ failure. He needed intubation, artificial ventilation and hemodynamic support. Blood culture samples grew gram-negative rods after four days of incubation, which were later identified as Capnocytophaga canimorsus. In continuation, the differential diagnosis in patients without a spleen who suddenly develop a septic shock is discussed. The importance of taking an exact exposure history to find the correct diagnosis is emphasized, including possible contacts with domestic animals.