Acquired bleeding disorders
Acute phase reaction

Authors: Kendall Crookston, M.D., Ph.D., Lizabeth Rosenbaum and Julie Gober-Wilcox, M.D. (see Authors page)

Revised: 2 March 2016, last major update September 2010

Copyright: (c) 2002-2016,, Inc.

PubMed Search: Acute phase reaction [title] coagulation
Cite this page: Acute phase reaction. website. Accessed July 18th, 2018.
Definition / general
  • Many serum proteins become elevated due to illness, injury, inflammation or stress
    • Also pregnancy
  • Elevated levels return to normal after condition resolves
  • Also called positive acute phase proteins
  • In response to injury, neutrophils and macrophages secrete IL-1, IL-6, IL-8 and TNF-a into the bloodstream
  • Production of other proteins is reduced ("negative" acute phase reactants)
  • Associated with increase in fibrinogen, factor VIII, vWF (up to 3x normal levels) and PAI-1 (up to 50x)
  • Associated with decrease in PTT, decrease in protein S (due to binding to increased C4b)