When interpreting the serological results, the history of the sample has to be taken into account. ARUP Consult® assists with test selection and interpretation. ADAMTS13 deficiency causes an acute haemolytic condition called Thrombotic Thrombocytopenic Purpura (TTP). • FRET (n = 18)or ELISA (n = 9). 24 Plasma ADAMTS13 activity begins to decrease at 12 to 16 gestational weeks. 0000016784 00000 n Expected turnaround time for a result, beginning when ARUP has received the specimen. 0000019898 00000 n 0000001926 00000 n 0000048225 00000 n 0000056202 00000 n Other names that describe the test. Lt. blue (sodium citrate). In congenital TTP, mutations in the ADAMTS13 gene prevent normal production and/or secretion of the enzyme. 0000015650 00000 n 0000015675 00000 n Normal ADAMTS13 activity (>=68%) and negative ADAMTS13 inhibitor (<=0.4 IU): No laboratory evidence of TTP. Incremental Recovery (IR) of ADAMTS13 Activity and ADAMTS13 Antigen [ Time Frame: Pre-dose, 15 minutes, 1, 3, 9, 24, 72, 120, 168, 216, 288, and 744 hours post dose ] IR will be estimated for ADAMTS13 activity and ADAMTS13 antigen (ADAMTS13Ag) following SHP655 or placebo infusion in both part A and part B participants. Some measurements of ADAMTS13 In this low range there may be residual ADAMTS13 activity, depending on the underlying mutations. • For estimates of ADAMTS13 antigen the combination of all results gave an ADAMTS13 activity by a method based on VWF-multimer electrophoresis, but this was superseded by a VWF-CBA assay. Usually USS patients have a severely deficient ADAMTS13 activity of <10% of the normal. The codes reflect our interpretation of CPT coding requirements based upon AMA guidelines published annually. 0000062643 00000 n In congenital TTP, also known as Upshaw-Schulman syndrome, mutations cause deficiency of ADAMTS13 which generally affects synthesis or secretion of the enzyme rather than causing production of dysfunctional molecules. Statistical analysis 0000004528 00000 n In acquired TTP, an IgG inhibitory antibody prevents the normal action of ADAMTS13. ADAMTS13 (a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13)—also known as von Willebrand factor-cleaving protease (VWFCP)—is a zinc-containing metalloprotease enzyme that cleaves von Willebrand factor (vWf), a large protein involved in blood clotting. 4. All were females (age range: 43 to 73, mean = 61.7 years) and had taken quinine for leg cramps. The VWF collagen binding method (VWF-CBA) was The ADAMTS13 enzyme cuts von Willebrand factor into smaller pieces to regulate its interaction with platelets. 0000035400 00000 n 1. To maximize the clinical utility of this test, Machaon Diagnostics is offering ADAMTS13 activity and inhibitor testing on a daily basis with clinical consultation. Primary (idiopathic or autoantibody-mediated), associated with severely decreased ADAMTS13 and the presence of ultra-large von Willebrand factor multimers Secondary (23 to 67 percent of cases), arising from a variety of conditions, including autoimmune disorders, solid organ or hematopoietic cell transplant, malignancy, drugs and pregnancy.. h�b```f``�g`e`�c`@ ���;�Y�R^G50` /]eހ�2�E�~�cQ�t��.���.g*�m���e0�e�p��[�Ӥ0��AD@�PVZZ�li �n�����Vb�I>�-�8��T�x�g[��P��� ߅�#�&4��xf�b��̙"���6���Hq|��P�s�%�f�u :$B� endstream endobj 26 0 obj <>>> endobj 27 0 obj <>/ExtGState<>/Font<>/ProcSet[/PDF/Text]/Properties<>>>>>/Rotate 0/TrimBox[0.0 0.0 612.0 792.0]/Type/Page>> endobj 28 0 obj [/ICCBased 57 0 R] endobj 29 0 obj <> endobj 30 0 obj <>stream Assist in diagnosing acquired (idiopathic) or inherited thrombotic thrombocytopenic purpura (TTP). Special Instructions Library of PDFs including pertinent information and forms related to the test. 0000001891 00000 n ADAMTS13 activity decreased progressively as from the period of 12-16 weeks up to the end of early puerperium (mean 52%, range 22-89, p < 0.0001), to increase slightly thereafter. The plasma half-life of administered ADAMTS13 in USS patients is around 2–4 days, whereas the protective effects seems to last longer. Normal plasma ADAMTS13 antigen levels span a concentration of 740-1420 ng/ml (median 1080 ng/ml) resulting in an ADAMTS13 activity to antigen ratio of 0.48 to 1.68 U/mug. The normal range for anti-ADAMTS-13 IgG was compared between the 5 different labs. 0000010438 00000 n CRITICAL FROZEN. By processing von Willebrand factor in this way, the enzyme prevents it from triggering the formation of blood clots in normal circulation. 0000025303 00000 n However, we detected reduced ADAMTS13 activity in a patient with Shiga toxin-producing Escherichia coli-associated HUS caused by non-IgG anti-ADMTS13 autoantibodies. Repeat ADAMTS13 testing while in clinical remission revealed a persistently low but improved ADAMTS13 activity of 15% of normal and persistence of a low-level inhibitor of 0.6 BU. Normal range/expected value(s) for a specific disease state. The American Medical Association Current Procedural Terminology (CPT) codes published in ARUP's Laboratory Test Directory are provided for informational purposes only. For questions regarding the Interface Map, please contact interface.support@aruplab.com. All samples had normal/high ADAMTS13 activity (Median activity for SDP = 94.0%, CSP = 80.5%, FFP = 122.0%) and plasminogen levels. In four patients the levels were > or = 18 times the upper limit of normal. Previous studies demonstrated that maternal plasma levels of ADAMTS13 activity decrease progressively to 23% of normal in the third trimester. 0000001338 00000 n The mature ADAMTS13 transcript has a size of 4.7 kb, giving rise to a precursor protein of 1427 amino acid residues [11–13]. 0000016236 00000 n Synonyms. The presence of ADAMTS13 inhibition (positive inhibitor screen) with a measurable antibody 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. All Rights Reserved. This test was performed in a CLIA certified laboratory and is intended for clinical purposes. For ADAMTS-13 INH, the median in these different populations varied between 6 and 9 U/ml which is well below the previously defined borderline value of 12 – 15 U/ml in this assay. ADAMTS13 [the 13th member of ADintegrin-like And Metalloprotease with ThromboSpondin type 13 motifs] is a metalloprotease which limits platelet aggregation and microthrombi formation in the microcirculation by cleaving Von Willebrand Factor [VWF] between Tyrosine 1605-Methionine 1606 [Tyr1605-Met1606] to generate a series of small molecular weight multimers. Separate specimens must be submitted when multiple tests are ordered. TTP is characterized by ADAMTS13 levels below 5-10% while aHUS is most often characterized by ADAMTS13 levels above 10%. vWF mutants with normal plasma or partially purified AD-AMTS13 reveals that the type 2A vWF mutants are cleaved by ADAMTS13 under static conditions.9 It is conceivable that in normal individuals, vWF is cleaved by ADAMTS13 only when it is exposed to high levels of shear stress in the arterioles or capillaries, whereas in patients with type 2A, 6-14 ADAMTS13 has also been referred to as von Willebrand factor-cleaving protease. Effective November 17, 2014 ... associated diseases, explanation of possible patient results. 0000017351 00000 n Five of the patients had D-Dimers levels measured, all were elevated. Congenital or acquired deficiency of ADAMTS13 is characterized by the presence in plasma of unusually large vWF factor multimers, which are more platelet-adhesive than the smaller multimers found in normal plasma. 0000017211 00000 n 0000013419 00000 n 0000001437 00000 n 0000035125 00000 n 0000015786 00000 n (Min: 0.5 mL). Assist in distinguishing between inherited and acquired forms of thrombotic thrombocytopenic purpura (TTP). Are you an ARUP Client? 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. In contrast to other ADAMTS proteases, ADAMTS13 is secreted into the circulation as an active enzyme [35] with a plasma half-life of approximately 2–3 days [62]. 0000006368 00000 n ADAMTS13 (a disintegrin and metalloprotease with thrombospondin 1 repeats) cleaves von Willebrand factor (vWF) between a tyrosine-1605 and methionine-1606 under circulatory conditions of high-shear stress. Mildly decreased ADAMTS13 activity (30-67%) and negative ADAMTS13 inhibitor (<=0.4 IU): Unlikely idiopathic TTP by laboratory findings and suggestive of TTP secondary to other clinical conditions. 0000013916 00000 n May include related or preferred tests. Results showed that the ADAMTS13 activity in newly diagnosed patients with AML before induction therapy was obviously lower than that in normal controls (63.3 ± 25.5) % versus (105.1 ± 37.7)(p < 0.01), while the VWF: Ag level was higher than that in normal controls (226.6 ± 127.0) % … In acquired TTP, inhibitory IgG class antibodies interfere with normal ADAMTS13 enzyme activity. Refer to Specimen Handling at aruplab.com for hemostasis/thrombosis specimen handling guidelines. 0000023125 00000 n 0000002039 00000 n It has not been cleared or approved by the US Food and Drug Administration. Reference Range: ADAMTS13 Activity Assay >or = 70% ADAMTS13 Inhibitor Screen Negative ADAMTS13 Bethesda Titer <0.4 BU <10% adamts13 activity is highly indicative of thrombotic thrombocytopenic purpura (TTP) in an appropriate clinical setting. ADAMTS13 levels of less than 10 percent may be associated with either inherited (Upshaw-Schulman Syndrome) or acquired thrombotic thrombocytopenic purpura (TTP). 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. [], and the detection limit of this assay was 3% of the normal control in our laboratory []. A prospective cross-sectional study of 270 normal pregnant and post-delivery women was carried out. 0000014772 00000 n The ADAMTS13 activity assay is an in vitro assay using a synthetic substrate peptide in a static liquid environment. Not all patients with a clinical diagnosis of idiopathic thrombotic thrombocytopenic purpura (TTP) have a severe ADAMTS13 deficiency. Recent plasma exchange therapy may raise the observed ADAMTS13 activity.This test was developed and its performance characteristics determined by ARUP Laboratories. The measured ADAMTS13 activity may not reflect the true in vivo biological ADAMTS13 activity. May also include abnormal ranges. Indicates test has been approved by the New York State Department of Health. 0000012702 00000 n TTP can be distinguished from other causes of MAHA by the finding of severely deficient ADAMTS13, typically <10% of normal. May include disease information, patient result explanation, recommendations, details of testing, associated diseases, explanation of possible patient results. Transfer 1 mL platelet-poor plasma to an ARUP Standard Transport Tube.