Ordering Recommendation

Reflexive panel to assist in diagnosis of thrombotic thrombocytopenic purpura (TTP) and in distinguishing between inherited and acquired forms of TTP.  

New York DOH Approval Status

This test is New York state approved.

Specimen Required

Patient Preparation

Light Blue (Sodium Citrate). Refer to Specimen Handling at aruplab.com for hemostasis/thrombosis specimen handling guidelines.

Specimen Preparation

Transfer 3 mL platelet-poor plasma to an ARUP Standard Transport Tube. (Min: 2 mL)

Storage/Transport Temperature

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

Unacceptable Conditions

Serum, or EDTA plasma. Clotted or hemolyzed specimens.


Ambient: 2 hours; Refrigerated: Unacceptable; Frozen: 2 weeks (No freeze/thaw cycles.)


Quantitative Enzyme-Linked Immunosorbent Assay




1-8 days

Reference Interval

Test Number
Reference Interval
  ADAMTS13 Activity Greater than 60 percent

Interpretive Data

Refer to report.

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)


If ADAMTS13 Activity is less than or equal to 30 percent, then ADAMTS13 Inhibitor will be added. If ADAMTS13 Inhibitor is less than 0.8 BU, then ADAMTS13 Antibody will be added. Additional charges apply.

Hotline History


CPT Codes

85397, if reflexed, add, 85335, if reflexed, add 83520


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.


ADAMTS13 Reflex Panel