Pulmonary leukostasis in fatal human pneumococcal bacteremia without pneumonia.

An asplenic man developed fulminant pneumococcal bacteremia without pneumonia. He died of irreversible shock within 24 h. Autopsy revealed extensive pulmonary vascular leukostasis. This condition has been described in laboratory animals after intravascular challenge with endotoxin, gram-negative bacilli, and gram-positive organisms including pneumococci. This case illustrates that death in pneumococcal disease can occur in the absence of pneumonia and may be attributable to cardiovascular collapse. We present a proposed mechanism based on activation of complement and release of vasoactive mediators.