Model for disseminated intravascular coagulation: bacterial sepsis in rhesus monkeys

DIC is a hemorrhagic syndrome frequently encountered as a complication in severe gram-negative bacterial sepsis. An animal model for sepsis-associated DIC was developed in order to permit study of the appearance and development of this syndrome in relation to the entire disease process. Rhesus monkeys (4 to 6 kg) were infected by intravenous injection of 10(9) Salmonella typhimurium organisms and studied for a period of 7 to 10 days following infection. Ten of 23 infected monkeys developed petechial rash characteristic of DIC, which appeared on days 1 to 2 infection and lasted 4 to 5 days. In the group of monkeys developing rash, activation of coagulation was suggested by an 80% decrease in platelet count and 20% to 30% increases in PT and APTT. Fibrinolytic system activation was indicated by the appearance of FDP. Kinin system activation was evidenced by decreases in both prekallikrein nad kininogen. Changes in laboratory tests suggestive of subclinical DIC were also noted in infected monkeys which did not develop a rash. Pathologic evidence of DIC was obtained through observation of numerous fibrin thrombi in the kidneys of the only monkey which died in the course of infection. Occurrence of DIC in association with this experimental infection in rhesus monkeys was established on the basis of clinical, laboratory, and pathologic criteria. Expression of the syndrome on days 1 to 2 following infection correlated with the period of increasing bacteremia.