Solvent/detergent-treated plasma suppresses shear-induced platelet
aggregation and prevents episodes of thrombotic thrombocytopenic purpura
J Moake, M Chintagumpala, N Turner, P McPherson, L Nolasco, C Steuber, P Santiago-Borrero, M Horowitz and J Pehta
Baylor College of Medicine, Houston, TX.
Two children with congenital chronic relapsing thrombotic thrombocytopenic
purpura (TTP) have episodes every 3 weeks. These relapses can be prevented
by the infusion of normal fresh-frozen plasma (FFP) without concurrent
plasmapheresis. We conducted a study to determine whether the exposure of
normal plasma to agents that inactivate human immunodeficiency virus and
other viruses destroys the component necessary for the effective treatment
of this type of TTP that requires only plasma infusion to prevent or
reverse relapses. Clinical responsiveness and von Willebrand factor
(vWF)-mediated fluid shear stress-induced platelet aggregation were
evaluated before and after the infusion of 10 mL/kg FFP or solvent [tri(n-
butyl)phosphate]/detergent (Triton X-100)-treated plasma (S/D plasma).
Platelet aggregation at shear stresses of 90 to 180 dyne/cm2 (similar to
those in the partially occluded microcirculation) imposed for 30 seconds
was excessive using the citrated platelet-rich plasma of both patients, and
was associated with the presence of unusually large vWF forms in patient
platelet-poor plasma. Infusion with either FFP or S/D plasma at 3-week
intervals caused the platelet count to increase to (or above) normal within
1 week (on 12 of 12 occasions); the disappearance or diminution of
unusually large vWF forms within 1 hour (on 6 of 10 occasions studied); and
the reversal within 1 to 4 hours of excessive shear-induced platelet
aggregation (on 8 of 9 occasions studied). We conclude that a component in
normal plasma resistant to S/D treatment is responsible for preventing
thrombocytopenia and TTP episodes, and for controlling excessive
shear-induced aggregation in these patients. Our results suggest that
excessive in vivo platelet aggregation in chronic relapsing TTP and
excessive in vitro vWF-mediated shear-induced aggregation may be similar
phenomena.
Volume 84,
Issue 2,
pp. 490-497,
07/15/1994
Copyright © 1994 by The American Society of Hematology
