Lupus anticoagulant aptt & drvvt screening panel W Reflex

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4 file:///c:/users/cholck/appdata/local/temp/relma_2_49_user_ Page 1 of Lupus anticoagulant aptt & drvvt screening panel W Reflex PANEL HIERARCHY LOINC# LOINC Name R/O/C CardinalityEx. UCUM Un Lupus anticoagulant aptt & drvvt screening panel W Reflex drvvt (LA screen) R-a s drvvt actual/ normal (normalized LA screen) R-a % drvvt with 1:1 PNP (LA mix) Rflx-a s drvvt with 1:1 PNP actual/ normal (normalized LA mix) Rflx-a % drvvt W excess phospholipid (LA confirm) Rflx-a s drvvt W excess phospholipid actual/ normal (normalized LA confirm) Rflx-a % drvvt/ drvvt W excess phospholipid (screen to confirm ratio) O drvvt W excess phospholipid percent correction O % aptt.lupus sensitive (LA screen) R-a s aptt.lupus sensitive actual/ normal (normalized LA screen) R-a aptt.lupus sensitive with 1:1 PNP (LA mix) Rflx-a s aptt.lupus sensitive with 1:1 PNP actual/ Normal (normalized LA mix) Rflx-a % aptt.lupus sensitive W excess phospholipid (LA confirm) Rflx-a s aptt.lupus sensitive W excess phospholipid actual/ Normal (normalized LA Rflx-a % confirm) aptt.lupus sensitive/ aptt.lupus sensitive W excess phospholipid (screen to O {Ratio} confirm ratio) aptt.lupus sensitive W excess phospholipid percent correction O % Lupus anticoagulant two screening tests W Reflex [interpretation] R Lupus anticoagulant two screening tests W Reflex panel - Pt PPP - Coag The development of this panel for detecting Lupus Anticoagulant (LA) was shaped by the 2009 International Society of Thrombosis and Haemostasis (ISTH) and 2014 Clinical and Laboratory Standards Institute (CLSI) guidelines for lupus anticoagulant testing. They both recommend using two separate coagulation tests and identify drvvt and appt as the two best choices. This appt & drvvt panel is most closely aligned with the ISTH guidelines. The testing cascade starts with the use of the two above-named tests to screen for or verify a clotting abnormality, and if either is abnormal, reflexing to the same test with 1:1 pooled plasma (to exclude clotting factor deficiencies) and again with excess phospholipid (PL). Correction of the coagulopathy with excess phospholipid confirms the likelihood of LA. Neither published guidance nor laboratories agree on the order in which the two kinds of reflex tests should be done, and this panel does not take a position on that subject. Some laboratories report the absolute values of the test and some the normalized ratios. So LOINC includes both as alternatives. Only one or the other of the alternatives must be included in the panel report. A summary interpretation is required by both guidelines. BASIC ATTRIBUTES Class/Type: PANEL.COAG/Lab Created On: 2014/09/11 Last Updated: 2014/12/03 Order vs. Obs.: Order Status: Active Copyright 2014 Regenstrief Institute, Inc. All Rights Reserved. To the extent included herein, the LOINC table and LOINC codes are copyright , Regenstrief Institute, Inc. and the Logical Observation Identifiers Names and Codes (LOINC) Committee. Generated from LOINC version 2.49.

5 Page 1 of Lupus anticoagulant aptt & drvvt & PT screening panel W Reflex PANEL HIERARCHY LOINC# LOINC Name R/O/C CardinalityEx. UCUM Un Lupus anticoagulant aptt & drvvt & PT screening panel W Reflex drvvt (LA screen) R-a s drvvt actual/ normal (normalized LA screen) R-a % drvvt with 1:1 PNP (LA mix) Rflx-a s drvvt with 1:1 PNP actual/ normal (normalized LA mix) Rflx-a % drvvt W excess phospholipid (LA confirm) Rflx-a s drvvt W excess phospholipid actual/ normal (normalized LA confirm) Rflx-a % drvvt W excess phospholipid percent correction O % drvvt/ drvvt W excess phospholipid (screen to confirm ratio) O aptt.lupus sensitive (LA screen) R-a s aptt.lupus sensitive actual/ normal (normalized LA screen) R-a aptt.lupus sensitive with 1:1 PNP (LA mix) Rflx-a s aptt.lupus sensitive with 1:1 PNP actual/ Normal (normalized LA mix) Rflx-a % aptt.lupus sensitive W excess phospholipid (LA confirm) Rflx-a s aptt.lupus sensitive W excess phospholipid actual/ Normal (normalized LA Rflx-a % confirm) aptt.lupus sensitive/ aptt.lupus sensitive W excess phospholipid (screen to O {Ratio} confirm ratio) aptt.lupus sensitive W excess phospholipid percent correction O % Prothrombin time (PT) R-a s Prothrombin time (PT) actual/ Normal R-a % Thrombin time Rflx-a s Thrombin time actual/ Normal Rflx-a % Reptilase time Rflx-a s Reptilase time actual/ Normal Rflx-a % Lupus anticoagulant three screening tests W Reflex [interpretation] R Lupus anticoagulant three screening tests W Reflex panel - Pt PPP - Coag The lupus anticoagulant three screen panel is based primarily on the 2009 International Society of Thrombosis and Haemostasis (ISTH) and 2014 Clinical and Laboratory Standards Institute (CLSI) guidelines for detecting the presence of lupus anticoagulants (LA), with some modifications based on information from major laboratories that use three screening tests (PT, aptt and drvvt) as the first step in LA testing. The ISTH guidelines recommend using drvvt as the first screening test and aptt-la as the second screening test, followed by reflex to mixing studies with 1:1 Pooled Normal Plasma and confirmatory testing with excess phospholipid (PL) if either of the screening tests are positive. The CLSI guidelines permit use of other screening tests in addition to aptt and drvvt, and also recommend changing the order of the tests to screening following by confirmatory and then mixing. Some major laboratories reflex to thrombin time (TT) and reptilase assays if any of the three screening tests have an abnormal result, so both of those tests are included in the panel. Both ISTH and CLSI recommend reporting quantitative results as the ratio of the patient result to the control result for each of the screening, mixing and confirmatory tests that are performed. However, they use different parameters for the control: ISTH recommends calculating the control based on pooled normal plasma (PNP), while CLSI recommends using the mean of the reference interval provided by the assay manufacturer. Many labs report either the actual patient result or the actual patient result and the actual/normal ratio, so we have included both options in the panel. In addition to the quantitative results, both guidelines recommend reporting a qualitative interpretation. Selected information about each LOINC that is part of this panel drvvt (LA screen)

6 Page 2 of 9 Coagulation dilute Russell viper venom induced Time Pt PPP Qn Coag Dilute Russell viper venom time (drvvt) is used most commonly as one of the screening tests to diagnose lupus anticoagulants (LA), which are phospholipid autoantibodies associated with excess clot formation, excess bleeding, and repeated miscarriages. The coagulant in the venom directly activates factor X, which turns prothrombin into thrombin in the presence of factor V and phospholipid. If phospholipid antibodies are present, this reaction will be inhibited, which will prolong the drvvt and suggests the presence of LA. [PMID: ] Both of the alternatives for reporting this measure -- actual patient time and actual/normal ratio -- are included in this panel. Reporting at least one of the two is required, but not both drvvt actual/ normal (normalized LA screen) Coagulation dilute Russell viper venom induced actual/normal RelTime Pt PPP Qn Coag Dilute Russell viper venom time (drvvt) is used most commonly as one of the screening tests to diagnose lupus anticoagulants (LA), which are phospholipid autoantibodies associated with excess clot formation, excess bleeding, and repeated miscarriages. The coagulant in the venom directly activates factor X, which turns prothrombin into thrombin in the presence of factor V and phospholipid. If phospholipid antibodies are present, this reaction will be inhibited, which will prolong the drvvt and suggests the presence of LA. [PMID: ] Both of the alternatives for reporting this measure -- actual patient time and actual/normal ratio -- are included in this panel. Reporting at least one of the two is required, but not both drvvt with 1:1 PNP (LA mix) DRVVT with 1:1 Pooled Normal Plasma Time Pt PPP Qn Coag Dilute Russell viper venom time (drvvt) is one of the tests used to detect the presence of lupus anticoagulants (LA), which are autoantibodies associated with excess clot formation, excess bleeding, and repeated miscarriages. The coagulant in the venom directly activates factor X, which turns prothrombin into thrombin in the presence of factor V and phospholipid. If phospholipid antibodies are present, this reaction will be inhibited, which will prolong the screening drvvt and suggests the presence of LA. A positive screening drvvt result may be followed by a drvvt mixing study using pooled normal plasma (PNP) from healthy donors as a source of coagulation factors. If the drvvt normalizes in the mixing study, a clotting factor deficiency is presumed to be the cause of the clotting abnormality.[pmid: ] Depending on the lab algorithm, this test may be a reflex from the screening and/or confirm drvvt. Both of the alternatives for reporting this measure-- actual patient time and actual/normal ratio -- are included in the panel drvvt with 1:1 PNP actual/ normal (normalized LA mix) DRVVT with 1:1 Pooled Normal Plasma actual/normal RelTime Pt PPP Qn Coag Dilute Russell viper venom time (drvvt) is one of the tests used to detect the presence of lupus anticoagulants (LA), which are autoantibodies associated with excess clot formation, excess bleeding, and repeated miscarriages. The coagulant in the venom directly activates factor X, which turns prothrombin into thrombin in the presence of factor V and phospholipid. If phospholipid antibodies are present, this reaction will be inhibited, which will prolong the screening drvvt and suggests the presence of LA. A positive screening drvvt result may be followed by a drvvt mixing study using pooled normal plasma (PNP) from healthy donors as a source of coagulation factors. If the drvvt normalizes in the mixing study, a clotting factor deficiency is presumed to be the cause of the clotting

7 Page 3 of 9 abnormality.[pmid: ] Depending on the lab algorithm, this test may be a reflex from the screening and/or confirm drvvt. Both of the alternatives for reporting this measure-- actual patient time and actual/normal ratio -- are included in the panel drvvt W excess phospholipid (LA confirm) Coagulation dilute Russell viper venom induced.excess phospholipid Time Pt PPP Qn If the coagulation defect corrects with excess phospholipid, it confirms the likely presence of phospholipid antibodies and the LA syndrome. Platelets, bilayer and hexagonal phospholipids are variously used as the source of excess phospholipids and this term covers them all. The use of one term for these variations reduces mapping work for practices that import laboratory results, but laboratories that use hexagonal phospholipids and think it important to distinguish their source can use instead of this term. Dilute Russell viper venom time (drvvt) is a screening laboratory test for detecting the presence of lupus anticoagulants (LA), which are autoantibodies associated with excess clot formation, excess bleeding, and repeated miscarriages. The coagulant in the venom directly activates factor X, which turns prothrombin into thrombin in the presence of factor V and phospholipid. If phospholipid antibodies are present, this reaction will be inhibited, which will prolong the screening drvvt and suggests the presence of LA. A confirmatory drvvt test measures drvvt in the presence of excess phospholipid, which saturates the antibody binding sites and thereby diminishes the inhibitory effect of the LA, resulting in a normalization of the drvvt. The drvvt screen to confirm ratio is calculated as Screen drvvt/confirm drvvt, and the drvvt percent correction is calculated as [(Screen drvvt - Confirm drvvt)/screen drvvt]x100. [PMID: ] Depending on the lab algorithm, this test may reflex from the screening and/or mixing drvvt. Both of the alternatives for reporting this measure-- actual patient time and actual/normal ratio -- are included in the panel drvvt W excess phospholipid actual/ normal (normalized LA confirm) Coagulation dilute Russell viper venom induced.excess phospholipid actual/normal RelTime Pt PPP Qn Coag If the coagulation defect corrects with excess phospholipid, it confirms the likely presence of phospholipid antibodies and the LA syndrome. Platelets, bilayer and hexagonal phospholipids are variously used as the source of excess phospholipids and this term covers them all. The use of one term for these variations reduces mapping work for practices that import laboratory results, but laboratories that use hexagonal phospholipids and think it important to distinguish their source can use instead of this term. Dilute Russell viper venom time (drvvt) is a screening laboratory test for detecting the presence of lupus anticoagulants (LA), which are autoantibodies associated with excess clot formation, excess bleeding, and repeated miscarriages. The coagulant in the venom directly activates factor X, which turns prothrombin into thrombin in the presence of factor V and phospholipid. If phospholipid antibodies are present, this reaction will be inhibited, which will prolong the screening drvvt and suggests the presence of LA. A confirmatory drvvt test measures drvvt in the presence of excess phospholipid, which saturates the antibody binding sites and thereby diminishes the inhibitory effect of the LA, resulting in a normalization of the drvvt. The drvvt screen to confirm ratio is calculated as Screen drvvt/confirm drvvt, and the drvvt percent correction is calculated as [(Screen drvvt - Confirm drvvt)/screen drvvt]x100. [PMID: ] Depending on the lab algorithm, this test may reflex from the screening and/or mixing drvvt. Both of the alternatives for reporting this measure-- actual patient time and actual/normal ratio -- are included in the panel.

8 Page 4 of drvvt W excess phospholipid percent correction DRVVT percent correction PctDiff Pt PPP Qn Coag The drvvt percent correction formula is based on the 2009 International Society on Thrombosis and Haemostasis lupus anticoagulant testing guidelines. [PMID: ] Dilute Russell viper venom time (drvvt) is a screening laboratory test for detecting the presence of lupus anticoagulants (LA), which are autoantibodies associated with excess clot formation, excess bleeding, and repeated miscarriages. The coagulant in the venom directly activates factor X, which turns prothrombin into thrombin in the presence of factor V and phospholipid. If phospholipid antibodies are present, this reaction will be inhibited, which will prolong the screening drvvt and suggests the presence of LA. A confirmatory drvvt test measures drvvt in the presence of excess phospholipid, which saturates the antibody binding sites and thereby diminishes the inhibitory effect of the LA, resulting in a normalization of the drvvt. The drvvt screen to confirm ratio is calculated as Screen drvvt/confirm drvvt, and the drvvt percent correction is calculated as [(Screen drvvt - Confirm drvvt)/screen drvvt]x100. [PMID: ] drvvt/ drvvt W excess phospholipid (screen to confirm ratio) Coagulation dilute Russell viper venom induced/coagulation dilute Russell viper venom induced.excess phospholipid Ratio Pt PPP Qn Coag Dilute Russell Viper Venom Time Confirmation reported as a Ratio as part of the Lupus Anticoagulant Panel. In the confirmatory assay, a second drvvt is performed using a reagent with additional phospholipids capable of neutralizing the LA. A ratio of the clotting times is calculated from the drvvt screening test divided by the drvvt confirmatory test. If a LA is present, the drvvt confirmatory test will correct to normal. The drvvt confirmatory reagent also contains a neutralizing agent for heparin in concentrations up to 1 unit/ml. Although patients on Coumadin or patients with deficiencies of factor II, V, and X may show prolonged times, the final ratio will be normal unless a LA is present. The drvvt confirmatory assay should be run only if the drvvt screening assay is elevated above the normal reference interval. In thei case, the confirmatory test is done and a ratio is calculated. If the ratio is greater than the upper limit of the established normal reference interval, the LA is present. If the ratio is less than or equal to the upper limit, the LA is absent. The drvvt screen to confirm ratio formula is based on the 2009 International Society on Thrombosis and Haemostasis lupus anticoagulant testing guidelines. [PMID: ] Dilute Russell viper venom time (drvvt) is used most commonly as one of the screening tests to diagnose lupus anticoagulants (LA), which are phospholipid autoantibodies associated with excess clot formation, excess bleeding, and repeated miscarriages. The coagulant in the venom directly activates factor X, which turns prothrombin into thrombin in the presence of factor V and phospholipid. If phospholipid antibodies are present, this reaction will be inhibited, which will prolong the drvvt and suggests the presence of LA. [PMID: ] aptt.lupus sensitive (LA screen) Coagulation surface induced.lupus sensitive Time Pt PPP Qn Coag Activated partial thromboplastic time.lupus sensitive (aptt-la), also called sensitive aptt, is a screening laboratory test often used as the first step in a testing cascade to detect the presence of lupus anticoagulants (LA), which are autoantibodies associated with excess clot formation, excess bleeding, and repeated miscarriages. Sensitive aptt has less phospholipid relative to the standard aptt reagent, which makes the test more sensitive to the presence of phospholipid antibodies. [PMID: ] The amount of phospholipid included in the aptt-la reagent is diminshed relative to the standard aptt reagent. Source: LOINC partner 1

9 Page 5 of 9 Both of the alternatives for reporting this measure -- actual patient time and actual/normal ratio -- are included in this panel. Reporting at least one of the two is required, but not both aptt.lupus sensitive actual/ normal (normalized LA screen) Coagulation surface induced.lupus sensitive actual/normal RelTime Pt PPP Qn Activated partial thromboplastic time.lupus sensitive (aptt-la), also called sensitive aptt, is a screening laboratory test often used as the first step in a testing cascade to detect the presence of lupus anticoagulants (LA), which are autoantibodies associated with excess clot formation, excess bleeding, and repeated miscarriages. Sensitive aptt has less phospholipid relative to the standard aptt reagent, which makes the test more sensitive to the presence of phospholipid antibodies. [PMID: ] The amount of phospholipid included in the aptt-la reagent is diminshed relative to the standard aptt reagent. Source: LOINC partner 1 Both of the alternatives for reporting this measure -- actual patient time and actual/normal ratio -- are included in this panel. Reporting at least one of the two is required, but not both aptt.lupus sensitive with 1:1 PNP (LA mix) Coagulation surface induced.lupus sensitive with 1:1 Pooled Normal Plasma Time Pt PPP Qn Coag A mixing study measures the aptt-la for a 1:1 mixture of the patient's sample with pooled normal plasma (PNP) from healthy donors as a source of coagulation factors. If the aptt normalizes in the mixing study, a clotting factor deficiency is presumed to be the cause of the clotting abnormality. [PMID: ] Depending on the lab algorithm, this test may be a reflex from the screening and/or confirm aptt. Both of the alternatives for reporting this measure-- actual patient time and actual/normal ratio -- are included in the panel aptt.lupus sensitive with 1:1 PNP actual/ Normal (normalized LA mix) Coagulation surface induced.lupus sensitive with 1:1 Pooled Normal Plasma actual/normal RelTime Pt PPP Qn Coag A mixing study measures the aptt-la for a 1:1 mixture of the patient's sample with pooled normal plasma (PNP) from healthy donors as a source of coagulation factors. If the aptt normalizes in the mixing study, a clotting factor deficiency is presumed to be the cause of the clotting abnormality. [PMID: ] Depending on the lab algorithm, this test may be a reflex from the screening and/or confirm aptt. Both of the alternatives for reporting this measure-- actual patient time and actual/normal ratio -- are included in the panel aptt.lupus sensitive W excess phospholipid (LA confirm) Coagulation surface induced.lupus sensitive.excess phospholipid Time Pt PPP Qn Coag

10 Page 6 of 9 If the coagulation defect corrects with excess phospholipid, it confirms the likely presence of phospholipid antibodies and the LA syndrome. Platelets, bilayer and hexagonal phospholipids are variously used as the source of excess phospholipids and this term covers them all. The use of one term for these variations reduces mapping work for practices that import laboratory results, but laboratories that use platelets or hexagonal phospholipids and think it important to distinguish their source can use or , respectively, instead of this term. Activated partial thromboplastic time with excess phospholipid is a confirmatory lab test for lupus anticoagulants (LA), which are phospholipid autoantibodies associated with excess clot formation, excess bleeding, and repeated miscarriages.confirmatory testing measures aptt in the presence of excess phospholipid, which saturates the antibody binding sites and thereby diminishes the inhibitory effect of the LA, resulting in a normalization of the aptt. The aptt screen to confirm ratio is calculated as Screen aptt/confirm aptt, and the aptt percent correction is calculated as [(Screen aptt - Confirm aptt)/screen aptt]x100. [PMID: ] Depending on the lab algorithm, this test may reflex from the screening and/or mixing aptt. Both of the alternatives for reporting this measure-- actual patient time and actual/normal ratio -- are included in the panel aptt.lupus sensitive W excess phospholipid actual/ Normal (normalized LA confirm) Coagulation surface induced.lupus sensitive.excess phospholipid actual/normal RelTime Pt PPP Qn Coag If the coagulation defect corrects with excess phospholipid, it confirms the likely presence of phospholipid antibodies and the LA syndrome. Platelets, bilayer and hexagonal phospholipids are variously used as the source of excess phospholipids and this term covers them all. The use of one term for these variations reduces mapping work for practices that import laboratory results, but laboratories that use hexagonal phospholipids and think it important to distinguish their source can use instead of this term. Activated partial thromboplastic time with excess phospholipid is a confirmatory lab test for lupus anticoagulants (LA), which are phospholipid autoantibodies associated with excess clot formation, excess bleeding, and repeated miscarriages.confirmatory testing measures aptt in the presence of excess phospholipid, which saturates the antibody binding sites and thereby diminishes the inhibitory effect of the LA, resulting in a normalization of the aptt. The aptt screen to confirm ratio is calculated as Screen aptt/confirm aptt, and the aptt percent correction is calculated as [(Screen aptt - Confirm aptt)/screen aptt]x100. [PMID: ] Depending on the lab algorithm, this test may reflex from the screening and/or mixing aptt. Both of the alternatives for reporting this measure-- actual patient time and actual/normal ratio -- are included in the panel aptt.lupus sensitive/ aptt.lupus sensitive W excess phospholipid (screen to confirm ratio) Coagulation surface induced.lupus sensitive/coagulation surface induced.lupus sensitive.excess phospholipid Ratio Pt PPP Qn Coag The aptt screen to confirm ratio formula is based on the 2009 International Society on Thrombosis and Haemostasis lupus anticoagulant testing guidelines. [PMID: ] Activated partial thromboplastic time.lupus sensitive (aptt-la), also called sensitive aptt, is a screening laboratory test often used as the first step in a testing cascade to detect the presence of lupus anticoagulants (LA), which are autoantibodies associated with excess clot formation, excess bleeding, and repeated miscarriages. Sensitive aptt has less phospholipid relative to the standard aptt reagent, which

11 Page 7 of 9 makes the test more sensitive to the presence of phospholipid antibodies. [PMID: ] The amount of phospholipid included in the aptt-la reagent is diminshed relative to the standard aptt reagent. Source: LOINC partner aptt.lupus sensitive W excess phospholipid percent correction Coagulation surface induced.lupus sensitive percent correction PctDiff Pt PPP Qn Coag The aptt percent correction formula is based on the 2009 International Society on Thrombosis and Haemostasis lupus anticoagulant testing guidelines. [PMID: ] Activated partial thromboplastic time with excess phospholipid is a confirmatory lab test for lupus anticoagulants (LA), which are phospholipid autoantibodies associated with excess clot formation, excess bleeding, and repeated miscarriages.confirmatory testing measures aptt in the presence of excess phospholipid, which saturates the antibody binding sites and thereby diminishes the inhibitory effect of the LA, resulting in a normalization of the aptt. The aptt screen to confirm ratio is calculated as Screen aptt/confirm aptt, and the aptt percent correction is calculated as [(Screen aptt - Confirm aptt)/screen aptt]x100. [PMID: ] Prothrombin time (PT) Coagulation tissue factor induced Time Pt PPP Qn Coag The prothrombin time (PT) and its derived measures of prothrombin ratio (PR) and international normalized ratio (INR) are measures of the extrinsic pathway of coagulation. They are used to determine the clotting tendency of blood, in the measure of warfarin dosage, liver damage and vitamin K status. The reference range for prothrombin time is usually around seconds; the normal range for the INR is It is used in conjunction with the activated partial thromboplastin time (aptt) which measures the intrinsic pathway. PT is sometimes used as the third screening test in the lupus anticoagulant testing algorithm and is included in the LOINC LA aptt & drvvt & PT panel. Copyright: Text is available under the Creative Commons Attribution/Share-Alike License. See for details. Source: Wikipedia, URL: Coagulation tissue factor induced (Wikipedia) Both alternatives for reporting this result--actual patient time and actual/normal ratio--are included in the panel. At least one of the two is required. This test may be used as a screening test in the context of LA testing but not in other contexts Prothrombin time (PT) actual/ Normal Coagulation tissue factor induced actual/normal RelTime Pt PPP Qn Coag The prothrombin time (PT) and its derived measures of prothrombin ratio (PR) and international normalized ratio (INR) are measures of the extrinsic pathway of coagulation. They are used to determine the clotting tendency of blood, in the measure of warfarin dosage, liver damage and vitamin K status. The reference range for prothrombin time is usually around seconds; the normal range for the INR is It is used in conjunction with the activated partial thromboplastin time (aptt) which measures the intrinsic pathway. PT is sometimes used as the third screening test in the lupus anticoagulant testing algorithm and is included in the LOINC LA aptt & drvvt & PT panel. Copyright: Text is available under the Creative Commons Attribution/Share-Alike License. See for details. Source: Wikipedia, URL: Coagulation tissue factor induced (Wikipedia)

12 Page 8 of 9 Both alternatives for reporting this result--actual patient time and actual/normal ratio--are included in the panel. At least one of the two is required. This test may be used as a screening test in the context of LA testing but not in other contexts Thrombin time Coagulation thrombin induced Time Pt PPP Qn Coag The thrombin clotting time (TCT), also known as the thrombin time (TT), is a coagulation assay which is usually performed to detect the therapeutic level of the anticoagulant heparin. It can also detect the presence of a fibrinogen abnormality. It is sometimes used in lupus anticoagulant screening, along with reptilase time, as a reflex test if any of the screening test results are out of range in order to detect the presence of heparin, dysfibrogenemia, or hypofibrogenemia. Copyright: Text is available under the Creative Commons Attribution/Share-Alike License. See for details. Source: Wikipedia, URL: Coagulation thrombin induced (Wikipedia) May reflex from PT, aptt or drvvt depending on lab algorithm. Both of the alternatives for reporting this measure-- actual patient time and actual/normal ratio -- are included in the panel Thrombin time actual/ Normal Coagulation thrombin induced actual/normal RelTime Pt PPP Qn Coag The thrombin clotting time (TCT), also known as the thrombin time (TT), is a coagulation assay which is usually performed to detect the therapeutic level of the anticoagulant heparin. It can also detect the presence of a fibrinogen abnormality. It is sometimes used in lupus anticoagulant screening, along with reptilase time, as a reflex test if any of the screening test results are out of range in order to detect the presence of heparin, dysfibrogenemia, or hypofibrogenemia. Copyright: Text is available under the Creative Commons Attribution/Share-Alike License. See for details. Source: Wikipedia, URL: Coagulation thrombin induced (Wikipedia) May reflex from PT, aptt or drvvt depending on lab algorithm. Both of the alternatives for reporting this measure-- actual patient time and actual/normal ratio -- are included in the panel Reptilase time Coagulation reptilase induced Time Pt PPP Qn Coag The Reptilase Clotting Time measures the conversion of fibrinogen to fibrin by snake venom Reptilase (Atroxin). The enzyme is similar to thrombin, but unlike thrombin, is not affected by the presence of heparin. It measures the availability of functional fibrinogen. It is sometimes used in lupus anticoagulant screening, along with thrombin time, as a reflex test if any of the screening test results are out of range in order to detect the presence of non-heparin anticoagulants, dysfibrogenemia, or hypofibrogenemia. Source: Regenstrief Institute Similar to thrombin time except that a snake venom instead of thrombin. Source: Regenstrief Institute May reflex from PT, aptt or drvvt depending on lab algorithm. Both of the alternatives for reporting this measure-- actual patient time and actual/normal ratio -- are included in the panel Reptilase time actual/ Normal Coagulation reptilase induced actual/normal RelTime Pt PPP Qn Coag

13 Page 9 of 9 The Reptilase Clotting Time measures the conversion of fibrinogen to fibrin by snake venom Reptilase (Atroxin). The enzyme is similar to thrombin, but unlike thrombin, is not affected by the presence of heparin. It measures the availability of functional fibrinogen. It is sometimes used in lupus anticoagulant screening, along with thrombin time, as a reflex test if any of the screening test results are out of range in order to detect the presence of non-heparin anticoagulants, dysfibrogenemia, or hypofibrogenemia. Source: Regenstrief Institute Similar to thrombin time except that a snake venom instead of thrombin. Source: Regenstrief Institute May reflex from PT, aptt or drvvt depending on lab algorithm. Both of the alternatives for reporting this measure-- actual patient time and actual/normal ratio -- are included in the panel Lupus anticoagulant three screening tests W Reflex [interpretation] Lupus anticoagulant three screening tests W Reflex Imp Pt PPP Nom Coag The answers included in the example answer list are based on the 2014 CLSI guidelines. If none the assays performed suggest the presence of LA, the overall result would be "LA not detected." If all of the assays performed suggest the presence of LA, the overall result would be "LA detected." If the presence or absence of LA cannot be confirmed without repeat testing, the overall result is "LA indeterminate." The 2009 ISTH guidelines include an alternative answer list with the following answers : 1. Findings compatible with the absence of lupus anticoagulants; 2. Findings compatible with the presence of lupus anticoagulants; and 3. To be tested again in 1 week. EXAMPLE ANSWER LIST (LL3115-4) SEQ# Answer Answer ID 1 Lupus anticoagulant present (3 screening test panel) LA Lupus anticoagulant not detected (3 screening test panel) LA Lupus anticoagulant indeterminate (3 screening test panel) LA Copyright 2014 Regenstrief Institute, Inc. All Rights Reserved. To the extent included herein, the LOINC table and LOINC codes are copyright , Regenstrief Institute, Inc. and the Logical Observation Identifiers Names and Codes (LOINC) Committee. Generated from LOINC version 2.49.