After testing, the residual … In LabCorp’s liquid chromatography‐tandem mass spectrometry (LC/MS-MS) assay, ADAMTS13 activity is determined by measuring the cleavage of a synthetic polypeptide substrate (referred to as vWF73) added to plasma samples. If ADAMTS13 activity is less than 30%, then reflex testing for an inhibitor and antibody will be performed. Recommendations when to order or not order the test. 85335-ADAMTS13 inhibitor screen assay (if appropriate) 85335-ADAMTS13 Bethesda titer (if appropriate) LOINC Code Information. 85335 – ADAMTS13 inhibitor screen assay (if appropriate) 85335 – ADAMTS13 Bethesda titer (if appropriate) Test Includes: Testing begins with ADAMTS13 activity assay to evaluate the percent activity. ADAMTS13 autoantibodies are not present in congenital TTP (Upshaw-Schulman syndrome). If specific inhibition is … Testing begins with ADAMTS13 activity assay to evaluate the percent activity. George JN: How I treat patients with thrombotic thrombocytopenic purpura: 2010. ADAMTS13 activity and inhibitor Adriana Doldan-Silvero,1 Carlos Acevedo-Gadea,2 Clandine Habib,1 Jonathan Freeman,1 and Vandita Johari1* Thrombotic thrombocytopenic purpura (TTP) is often associated with acquired or congenital deficiency of ... ADAMTS13 testing is most helpful as an indicator for risk of relapse of all forms of TTP and in the diagnosis of inher-ited TTP. If the ADAMTS13 activity assay is less than 30%, an inhibitor screen will be performed to look for specific ADAMTS13 inhibition. ARUP Consult® assists with test selection and interpretation. © 2021 ARUP Laboratories. All Rights Reserved. Recent plasma exchange or transfusion may falsely normalize ADAMTS13 levels, thus potentially masking the diagnosis of TTP. Therefore, clinical correlation is recommended. Blood 2008 Jul 1;112(1):11-18, 2. If specific inhibition is apparent, the titer of the inhibitor will be determined. Report Includes. Specimens. If the ADAMTS13 activity assay is less than 30%, an inhibitor screen will be performed to look for specific ADAMTS13 inhibition. ADAMTS13 Bethesda assays detect antibodies that neutralize function, which are present in approximately two-thirds of TTP cases. Results. 1. Shaded areas show normal ranges, and the vertical bars indicate values of mean±SD. Method. If specific inhibition is apparent, the titer of the inhibitor will be determined. Blood 2010 Nov 18;116(20):4060-4069, 3. If inhibitor result is = 0.7 Inhibitor Units, the antibody assay (1299) is performed. If specific inhibition is apparent, the titer of the inhibitor will be determined. Introduction: Quantitation of ADAMTS13 activity, functional inhibitors, and autoantibodies is crucial in diagnosis and management of thrombotic thrombocytopenic purpura. Testing begins with ADAMTS13 activity assay to evaluate the percent activity. Testing begins with ADAMTS13 activity assay to evaluate the percent activity. 7 days. Correlation with clinical information, ADAMTS13 activity, and other relevant laboratory testing is suggested. If specific inhibition is apparent, the titer of the inhibitor will be determined. Utility of ADAMTS13 Testing in Assessing Risk of Relapse of Acquired TTP ADAMTS13 Activity at Time of Initial Diagnosis It has not been cleared or approved by the US Food and Drug Administration. ADAMTS13 Inhibitor Bethesda Titer: No: No: Testing Algorithm Delineates situations when tests are added to the initial order. Interferences of ADAMTS13 activity assay include high levels of endogenous von Willebrand factor, hyperlipidemia, hemolysis with plasma free hemoglobin greater than 2 g/L, hyperbilirubinemia (bilirubin concentration >100 micromolar), and cleavage by other protease. ^lt;10%) ADAMTS-13 activity. If specific inhibition is apparent, the titer of the inhibitor will be determined. Not all patients with a clinical diagnosis of idiopathic thrombotic thrombocytopenic purpura (TTP) have a severe ADAMTS13 deficiency. Assisting with the diagnosis of congenital or acquired thrombotic thrombocytopenic purpura. The IgG antibody prevents this cleavage and leads to TTP. If the ADAMTS13 activity assay is less than 30%, an inhibitor screen will be performed to look for specific ADAMTS13 inhibition. Testing begins with ADAMTS13 activity assay to evaluate the percent activity. Clotted or hemolyzed specimens. If specific inhibition is apparent, the titer of the inhibitor will be determined. Testing begins with ADAMTS13 activity assay to evaluate the percent activity. Assist in distinguishing between inherited and acquired forms of thrombotic thrombocytopenic purpura (TTP). CRITICAL FROZEN. Authors Adriana Doldan-Silvero 1 , Carlos Acevedo-Gadea, Clandine Habib, Jonathan Freeman, Vandita Johari. ADAMTS-13 Inhibitor. The presence of ADAMTS13 inhibition (positive inhibitor screen) with a measurable antibody titer is most consistent with an acquired TTP. Are you an ARUP Client? Testing begins with ADAMTS13 activity assay to evaluate the percent activity. This test has not yet been approved by the U.S. Food and Drug Administration (FDA) or Health Canada, thus is considered a research test. Less than 10% ADAMTS13 activity is highly indicative of thrombotic thrombocytopenic purpura (TTP) in an appropriate clinical setting. Suggests clinical disorders or settings where the test may be helpful. ADAMTS13 (a disintegrin and metalloproteinase with thrombospondin type 1 motif, 13) is a metalloprotease responsible for cleavage of ultra-large von Willebrand factor (VWF) multimers. Additional Test Information. Therefore, TTP remains a clinical diagnosis. Autoantibodies that neutralize ADAMTS13 function are found in approximately two-thirds of idiopathic cases and can be identified and titered by the ADAMTS13 inhibitor test. Testing begins with ADAMTS13 activity assay to evaluate the percent activity. ADAMTS13 Activity with Reflex to Inhibitor - ADAMTS-13 is a zinc metalloprotease that cleaves ultra large vWF multimers. Indicates test has been approved by the New York State Department of Health. May include related or preferred tests. Ambient: 2 hours; Refrigerated: Unacceptable; Frozen: 2 weeks (No freeze/thaw cycles.). If specific inhibition is May include disease information, patient result explanation, recommendations, details of testing, associated diseases, explanation of possible patient results. Name Units Reference Range Conversion Factor; ADAMTS-13 Activity: U/mL: Normal: >0.40; Decreased: 0.10 - 0.40; Very Low: <0.10; Thrombotic Thrombocytopenic Purpura (TTP) is generally associated with a severe deficiency (i.e. If result is = 30%, the inhibitor assay (1297) is performed. If the ADAMTS13 activity assay is less than 30%, an inhibitor screen will be performed to look for specific ADAMTS13 inhibition. Light Blue (Sodium Citrate). If the ADAMTS13 activity assay is less than 30%, an inhibitor screen will be performed to look for specific ADAMTS13 inhibition. The ADAMTS13 activity is measured by a fluorescence resonance energy transfer (FRET)-based assay using a 73 amino-acid peptide (FRETS-VWF73) of von Willebrand factor (VWF) as substrate. It has not been cleared or approved by the US Food and Drug Administration. Serum or EDTA plasma. Non-neutralizing antibodies are not detected in the inhibitor test but can be detected by ELISA (ADAMTS13 antibody test). Testing begins with ADAMTS13 activity assay to evaluate the percent activity. TTP. ADAMTS13 cleaves the ultra-high-molecular-weight multimers of von Willebrand factor (VWF) at the peptide bond Tyr1605-Met1606 to disrupt VWF-induced platelet aggregation. Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test. Severely deficient activity of the protease can trigger an acute episode of thrombotic thrombocytopenic purpura (TTP). Interface / Setup. If suspicion for TTP remains after a negative result, ADAMTS13 Antibody (3000182) is recommended. Test Name: ADAMTS13 Inhibitor: Alternative Name(s) VWF-cleaving Protease Inhibitor: Draw Kits Available? Citrated Plasma (light blue top) Although the diagnosis of TTP may be confirmed with ADAMTS13 activity and inhibition studies, the decision to initiate plasma exchange should not be delayed pending results of this assay. 23 The amino acid sequence of vWF73 corresponds to amino acid residues 1596 through 1668 of mature von Willebrand Factor (vWF) and, thereby, possesses the … Provides information to assist in interpretation of the test results, Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances, Recommendations for in-depth reading of a clinical nature, Library of PDFs including pertinent information and forms related to the test, Customized Instructions & Shipping Guides, Coagulation Guidelines for Specimen Handling and Processing. Test Location. Affiliation 1 Department of Pathology, Baystate ... and it is therefore not recommended as an initial test for diagnosis (Copelovitch and Kaplan, Pediatr Nephrol, in press). Click here for your pricing. Sample Requirements. Additional information related to the test. Inhibitor testing is performed (at additional charge) if the ADAMTS13 activity is ≤30%. Other names that describe the test. For now, it … May also include abnormal ranges. Reflex ADAMTS-13 Inhibitor testing will be performed only if ADAMTS-13 Activity is <0.10 U/mL. Thrombotic thrombocytopenic purpura (TTP), a rare (estimated incidence of 3.7 cases per million) and potentially fatal thrombotic microangiopathy (TMA) syndrome, is characterized by a pentad of symptoms: thrombocytopenia, microangiopathic hemolytic anemia (intravascular hemolysis and presence of peripheral blood schistocytes), neurological symptoms, fever, and renal dysfunction. ADAMTS13 Evaluation is a reflexive testing algorithm for evaluation of TTP. Refer to Specimen Handling at aruplab.com for hemostasis/thrombosis specimen handling guidelines. ON,CA. This includes reflex and additional tests. ADAMTS13 autoantibodies are not present in congenital TTP (Upshaw-Schulman syndrome). The American Medical Association Current Procedural Terminology (CPT) codes published in ARUP's Laboratory Test Directory are provided for informational purposes only. Expected turnaround time for a result, beginning when ARUP has received the specimen. If the ADAMTS13 activity assay is less than 30%, an inhibitor screen will be performed to look for specific ADAMTS13 inhibition. Acquired TTP may be considered to be primary or idiopathic (the most frequent type), or associated with distinctive clinical conditions (secondary TTP) such as medications, hematopoietic stem cell or solid organ transplantation, sepsis, and malignancy. Flourescence Resonance Transfer Assay (FRET) Test Information. Testing begins with ADAMTS13 activity assay. ADAMTS13 activity and inhibitor Am J Hematol. Conversely, patients with other non-TTP conditions may have a severe ADAMTS13 deficiency (< or =10%). If specific inhibition is apparent, the titer of the inhibitor will be determined. This test was performed in a CLIA certified laboratory and is intended for clinical purposes. The inhibitor screen and titer assay are performed by using mixing studies that are similar to the Bethesda assay. If the ADAMTS13 activity assay is less than 30%, an inhibitor screen will be performed to look for specific ADAMTS13 inhibition. All Rights Reserved. Testing Algorithm. Abstract. Mitogen’s ADAMTS-13 Activity and Autoantibodies / Inhibitors assay is a dual autoimmune and enzyme activity diagnostic test that is useful in the diagnosis of hemolytic/uremic syndrome (HUS), atypical hemolytic uremic syndrome (aHUS), and thrombotic thrombocytopenia purpura (TTP). Background information for test. The patient’s sample is heat-inactivated and mixed with an equal volume of pooled normal plasma (PNP) before testing. What prompts reflex to ADAMTS13 inhibitor testing? Sadler JE: Von Willebrand factor, ADAMTS13, and thrombotic thrombocytopenic purpura. The large majority of patients initially present with thrombocytopenia and peripheral blood evidence of microangiopathy, and in the absence of any other potential explanation for such findings, satisfy criteria for early initiation of plasma exchange, which is critical for patient survival. Non-neutralizing autoantibodies that result in increased ADAMTS13 clearance, but do not inhibit function, are found in approximately one-third of idiopathic TTP cases. Correlation with clinical information, ADAMTS13 activity, and other relevant laboratory testing is suggested.This test was developed and its performance characteristics determined by ARUP Laboratories. The codes reflect our interpretation of CPT coding requirements based upon AMA guidelines published annually. It may also be used to monitor the response to therapy for Acute TTP Read More Activity is always performed. We compared and optimized commercial assay kits and validated a testing panel. Quantitative Enzyme-Linked Immunosorbent Assay. Describes reference intervals and additional information for interpretation of test results. The presence of ADAMTS13 inhibition (positive inhibitor screen) with a measurable antibody titer is most consistent with an acquired TTP. Normal range/expected value(s) for a specific disease state. We found that a commercial ADAMTS13 (Technoclone Technozym) antibody assay is falsely negative in a substantial proportion of patients with autoimmune TTP, the majority of which likely had a low titer inhibitor, below the threshold of test detection. Separate specimens must be submitted when multiple tests are ordered. 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. TTP may rarely be congenital (Upshaw-Shulman syndrome), but far more commonly is acquired. Testing Algorithm. This includes reflex and additional tests. If specific inhibition is apparent, the titer of the inhibitor will be determined. Testing begins with ADAMTS13 activity assay to evaluate the percent activity. This test was performed in a CLIA … If the ADAMTS13 activity assay is less than 30%, an inhibitor screen will be performed to look for specific ADAMTS13 inhibition. The isolation and characterization of an IgG autoantibody frequently found in patients with idiopathic TTP, clarified the basis of this entity and led to the isolation and characterization of a metalloprotease called ADAMTS13 (a disintegrin and metalloprotease with thrombospondin type 1 motif 13 repeats), which is the target for the IgG autoantibody, leading to a functional deficiency of ADAMTS13. If specific inhibition is apparent, the titer of the inhibitor will be determined. Intervals are Mayo-derived, unless otherwise designated. If specific inhibition is apparent, the titer of the inhibitor will be determined. von Willebrand factor-cleaving protease (VWFCP); ADAMTS13; ADAMTS 13. Testing begins with ADAMTS13 activity assay to evaluate the percent activity. Not recommended as initial test for identification of autoantibodies to ADAMTS13, since the ADAMTS13 antibody test is less specific for acquired TTP than ADAMTS13 Inhibitor ( 3000228 ). If the ADAMTS13 activity assay is less than 30%, an inhibitor screen will be performed to look for specific ADAMTS13 inhibition. Delineates situations when tests are added to the initial order. The use of and ELISA ADAMTS13 IgG inhibitor assay may distinguish between congenital and acquired deficiencies. If the ADAMTS13 activity assay is less than 30%, an inhibitor screen will be performed to look for specific ADAMTS13 inhibition. Synonyms. Commercially … These conditions include hemolytic uremic syndrome, hematopoietic stem cell and solid organ transplantation, liver disease, disseminated intravascular coagulation, sepsis, pregnancy, and certain medication. Testing begins with ADAMTS13 activity assay to evaluate the percent activity. 2008 Oct;83(10):811-4. doi: 10.1002/ajh.21257. Indications. von Willebrand Factor Cleaving Protease Inhibitor. 10-Jan-2020. Low levels of ADAMTS13 are also associated with an increased risk of arterial thrombosis, including myocardial infarction and cerebrovascular disease. If the ADAMTS13 activity assay is less than 30%, an inhibitor screen will be performed to look for specific ADAMTS13 inhibition. N Engl J Med 1978 Jun 15;298(24):1350-1352. Test Version. and ADAMTS13 Testing Dong Chen MD PhD Special Coagulation Laboratory Mayo Clinic-Rochester ... due to ADAMTS13 Inhibitor Boosting Isonishi A, et al. The impact of ADAMTS13 levels and presence of inhibitors on overall survival, ultimate clinical outcome, responsiveness to plasma exchange, and relapse are still controversial. adamts13_evaluation_desc.pdf. HL7 Interface … Testing Algorithm. Since the discovery of ADAMTS13, specific epitopes on its surface have been shown to be the target of inhibitory antibodies. ADAMTS13 inhibitors are measured using the same ELISA method. Transfer 1 mL platelet-poor plasma to an ARUP Standard Transport Tube. Many prospective and retrospective … If the ADAMTS13 activity is 30%, an inhibitor screen will be performed to look for specific ADAMTS13 inhibition. If an interpretive report is provided, the reference value field will state this. If the ADAMTS13 activity assay is less than 30%, an inhibitor screen will be performed to look for specific ADAMTS13 inhibition. If specific inhibition is apparent, the titer of the inhibitor will be determined. Testing Algorithm. … If specific inhibition is … Question 4. ADAMTS13 autoantibody testing also differentiates acquired TTP from rare cases of hereditary TTP caused by ADAMTS13 mutations (Upshaw-Schulman syndrome). Recommended initial test for the identification of autoantibodies to ADAMTS13, since the ADAMS13 inhibitor test is more specific for acquired TTP than the ADAMTS13 antibody test. Method. Cautions Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances If the ADAMTS13 activity assay is less than 30%, an inhibitor screen will be performed to look for specific ADAMTS13 inhibition. © 1995–2021 Mayo Foundation for Medical Education and Research. If the ADAMTS13 activity assay is <30%, an inhibitor screen will be performed to look for specific ADAMTS13 inhibition. Testing Algorithm. For questions regarding the Interface Map, please contact interface.support@aruplab.com. What method is used for the inhibitor assay? This test was developed and its performance characteristics determined by ARUP Laboratories. (Min: 1 mL). Transfusion. TTP may be … Testing begins with ADAMTS13 activity assay to evaluate the percent activity. Testing Schedule: Sun-Sat : Expected TAT: 1-3 days : Notes: Reference Lab: ARUP Test Code: 3000228 Click Here to view information on the ARUP website. Methods: Citrated plasma specimens from healthy volunteers and residual samples submitted for clinical testing were used in the study. Assist in distinguishing between inherited and acquired forms of thrombotic thrombocytopenic purpura (TTP). Upshaw JD: Congenital deficiency of a factor in normal plasma that reverses microangiopathic hemolysis and thrombocytopenia. If specific inhibition is apparent, the titer of the inhibitor will be determined. 2015; 55: 2321-30. Yes: Days Performed: 7 days/week: Methodology: ELISA: Normal Range: Negative: Reflexive Testing: ADAMTS-13 Antibody: Associated Testing: Special Instructions & Forms: Rejection Criteria > 7 days old if stored at 2-25°C; thawed if shipped frozen: Description May include intervals based on age and sex when appropriate. Turnaround Time. The ADAMTS13 activity assay is an in vitro assay using a synthetic substrate peptide in a static liquid environment. Testing begins with ADAMTS13 activity assay to evaluate the percent activity. The measured ADAMTS13 activity may not reflect the true in vivo biological ADAMTS13 activity. The majority of cases of idiopathic thrombotic thrombocytopenic purpura (TTP) are caused by ADAMTS13 autoantibodies. ELISA. ADAMTS 13 Inhibitor (test performed if activity level <30%) Also Known as (Alias) ATS-13 Inhibitor.