Ordering Recommendation

Assist in diagnosing acquired (idiopathic) or inherited thrombotic thrombocytopenic purpura (TTP).

New York DOH Approval Status

This test is New York state approved.

Specimen Required

Patient Preparation

Lt. blue (sodium citrate). Refer to Specimen Handling at aruplab.com for hemostasis/thrombosis specimen handling guidelines.

Specimen Preparation

Transfer 1 mL platelet-poor plasma to an ARUP Standard Transport Tube. (Min: 0.5 mL)

Storage/Transport Temperature

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

Unacceptable Conditions

Serum, EDTA plasma, clotted or hemolyzed specimens.


Ambient: 2 hours; Refrigerated: Unacceptable; Frozen: 2 weeks


Chromogenic Assay




1-3 days

Reference Interval

Effective November 17, 2014

Greater than 60 percent

Interpretive Data

ADAMTS13 levels of less than 10 percent may be associated with either inherited (Upshaw-Schulman Syndrome) or acquired thrombotic thrombocytopenic purpura (TTP).

A variety of medical conditions may result in a mild to moderate deficiency of ADAMTS13 activity. Recent plasma exchange therapy may raise the observed ADAMTS13 activity.

This test was developed and its performance characteristics determined by ARUP Laboratories. It has not been cleared or approved by the US Food and Drug Administration. This test was performed in a CLIA certified laboratory and is intended for clinical purposes.

Compliance Category

Laboratory Developed Test (LDT)


Hotline History


CPT Codes



Component Test Code* Component Chart Name LOINC
0030049 ADAMTS13 Activity 53622-7
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.


  • von Willebrand Factor Cleaving Protease
ADAMTS13 Activity