ADAMTS13 Activity with Reflex to Inhibitor : 14532

CRITICAL FROZEN. Separate specimens must be submitted when multiple tests are ordered.

ADAMST or 14532

VWF CLEAVING PROTEASE, vWF-CP, von Willebrand Factor, vWF Protease Activity

If ADAMTS13 Activity is less than or equal to 0.30 IU/mL , ADAMTS13 Inhibitor will be performed at an additional charge (CPT code: 85335). 

Lt. blue (3.2% sodium citrate).

Centrifuge light blue-top tube 15 minutes at approx. 1500 g within 60 minutes of collection. Using a plastic pipette, remove plasma, taking care to avoid the WBC/platelet buffy layer and place into a plastic vial. Centrifuge a second time and transfer platelet-poor plasma into standard plastic transport tube. Freeze immediately 1 mL plasma (Min. 0.5 mL).

Frozen.

Ambient: Unacceptable; Refrigerated: Unacceptable; Frozen: 21 days

Gross Hemolysis,  Grossly Lipemic, Grossly Icteric

Sunday - Thursday

2-4 days (From receipt at performing laboratory)

This test was performed using a kit that has not been cleared or approved by the FDA. The analytical performance characteristics of this test have been determined by Quest Diagnostics. This test should not be used for diagnosis without confirmation by other medically established means.

ADAMTS13 Activity 0.68-1.63 IU/mL 

ADAMTS-13 is a zinc metalloprotease that cleaves ultra large vWF multimers. Studies have shown that low levels of ADAMTS-13 activity are associated with thrombotic thrombocytopenic purpura (TTP), a life-threatening hematological condition characterized by a low platelet count, microvascular thrombi, red cell fragmentation, and renal complications. Congenital TTP is a rare inherited disease caused by mutations within the ADAMTS-13 gene, which result in the production of non-functional protein. The acquired form of TTP is an autoimmune-like disorder caused by the development of autoantibodies to ADAMTS-13 that inhibits enzyme activity.