Hemophagocytic syndrome with severe sepsis caused by Capnocytophaga canimorsus.

Capnocytophaga canimorsus, commonly transmitted by dog bites, can cause severe sepsis, and the mortality rate is very high. We experienced a case of hemophagocytic lymphohistiocytosis (HLH) complicated by severe sepsis caused by C. canimorsus. A 58-year-old man with no remarkable medical history was admitted to another hospital with fever and mild consciousness disorder developed 3 days after being bitten by his dog. The next day, the patient developed disseminated intravascular coagulation and shock and was transferred to our emergency medical center. Blood tests showed hyperferritinemia and cytopenia, and bone marrow aspiration was performed. As a result, we diagnosed severe sepsis and HLH. Once antibiotic and steroid therapy was started, the patient's infection and cytopenia improved. Unfortunately, the patient's fingers and toes required amputation, but his life was saved, and he was discharged from hospital. Because HLH may be hidden in such cases, it may be necessary to measure serum ferritin and perform bone marrow aspiration if hyperferritinemia is suspected.