Q: Which one disease process in ICU may give prolong ACT (Activated Clotting Time) ?

Answer:  Lupus anticoagulant (LA)

In patients with Lupus anticoagulant, other tests should be considered. ACT becomes unreliable in patients with LA.

In some patients the presence of a lupus anticoagulant has been shown to interfere with and prolong the ACT but in other cases the ACT may be relatively unaffected.