We retrospectively analyzed clinical data and autopsy findings of patients (n = 107), who died in our medical ICU. Data included age, sex, medical history, reason for last admission, diagnosis, APACHE II-score, TISS-score and SOFA-score, transfusion requirements, complications, relevant laboratory findings as well as the cause of death. Bone marrow samples obtained at autopsy were histochemically stained with hematoxylin-eosin and prussian blue reaction. Immunohistochemistry with monoclonal antibodies against CD68, CD61 and myeloperoxidase (all DAKO, Hamburg/ Germany) was done to identify and quantify the hemopoietic cell lines mainly affected by the HHH. The hemophagocytic activity was graded from mild to severe HHH according to Suster et al. . Cases showing moderate to severe hemophagocytic activity were classified as having HHH. Statistical analysis was performed using chi-square-test, correlational and logistic regression analysis.