Plasma-derived antithrombin III (ATIII) prevents the lethal effects of Escherichia coli infusion in baboons, but the mechanisms behind this effect are not clear. In the present study, we evaluated the effects of recombinant human ATIII (rhATIII) on the clinical course and the inflammatory cytokine and coagulation responses in baboons challenged with lethal dose of E coli. Animals in the treatment group (n = 5) received high doses of rhATIII starting 1 hour before an E colichallenge. Those in the control group were administered saline. Survival was significantly improved in the treatment group (P = .002). Both groups had similar hemodynamic responses to E coli challenge but different coagulation and inflammatory responses. The rhATIII group had an accelerated increase of thrombin-ATIII complexes and significantly less fibrinogen consumption compared to controls. In addition, the rhATIII group had much less severe thrombotic pathology on autopsy and virtually no fibrinolytic response to E coli challenge. Furthermore, the rhATIII group had a significantly attenuated inflammatory response as evidenced by marked reduction of the release of various cytokines. We conclude that the early administration of high doses of rhATIII improves the outcome in baboons lethally challenged with E coli, probably due to the combined anticoagulation and anti-inflammatory effects of this therapy.

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There is considerable controversy regarding the effect of Prednisone on the hemostatic mechanism of normal people versus patients with bleeding diatheses. We administered Prednisone 15 mg TID to patients with a positive history of a bleeding disorder, and evaluated the bleeding time and other in-vitrc tests of platelet function prior to and between the 5th and 7th day after Prednisone.Eleven patients were admitted into this study over a one year period. All patients had a history of excessive bruising, epistaxis, bleeding after dental extractions, and gastrointestinal or other bleeding in various combinations. Two out of the eleven had template bleeding times of greater than 15 minutes both before and after the Prednisone. These two patients were subsequently proven to have von Willebrand’s disease by the washed platelet ristocetin assay. In the remaining 9 patients, the pre-Prednisone bleeding time was 9.3 ±3.7 minutes (x ± 1 S.D.) whereas the post-Prednisone bleeding time was 5.8 ±3.6 minutes (x ±1 S.D.). These results were significant(td=3.83;df:7;p=0.007).Platelet aggregation in response to exogenous ADP (1 μM, 3 μM) Sigma bovine tendon collagen (1.8 mg/ml F) and epinephrine (5.5 × 104M), platelet retention in a glass bead column or platelet factor 3 availability did not improve or worsen after Prednisone therapy. The mean platelet count of 328,000±94,000 (x ±1 S.D.) was significantly (p=0.05) higher than the mean pre-Prednisone platelet count of 268,000±77,000 (x ±1 S.D.).In conclusion, we have shown that large doses of Prednisone appear to shorten the bleeding time in patients with significant defects in the primary hemostatic mechanism. However the bleeding time improvement is not evident in patients with von Willebrand’s disease.