LUPUS ANTICOAGULANT LABORATORY CODE NUMBER: 900

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1 ECAT FOUNDATION EXERCISE 21-3 INTERNATIONAL EXTERNAL QUALITY ASSESSMENT Page 1 of 12 LUPUS ANTICOAGULANT LABORATORY CODE NUMBER: 9 Test plasma : 1.57 Type of plasma : Lupus Inhibitor Plasma Low (Technoclone, lot no. 2U1B) Former used in exercise : - Number of participants : 433 Number of responders : 391 Participation rate : 9% General remarks 1. To make the calculation of ratios possible we entered the maximum measured value into the database when results were reported as >[value]. 2. This weakly positive Lupus Anticoagulant sample was positively tested in the drvvt test of Technoclone (LA ratio: 1.45). 3. Twenty-eight participants did not gave a final conclusion (!). Please do not forget to fill in the final conclusion in future surveys. Negative classification This weakly positive lupus sample was negatively classified by 41 participants (~1%)!!! Screening tests About 14% of the screening tests was classified as normal, mainly caused by the APTT group (~7% of all normal classifications). The following reagents gave a high percentage normal classification: Patromtin SL (Siemens, n=29) [28%], Actin FSL (Siemens, n=46) [75%], Platelin L (Tritiny Biotech, n=5) [1%], Platelin LS (Trinity Biotech, n=9) [44%], HemosIL SynthASil (I.L., n=13) [46%]. On the other hand, the following reagents gave a high percentage of prolonged classification: APTT SP (I.L., n=37) [81%], PTT LA (Stago, n=73) [97%], APTT STA / PTT Automate (Stago, n=34) [82%]. Mixing tests About 47% (n=222) of all mixing tests (n=472) was classified as normal. For the APTT assay group this was ~44% and for the DRVTT assay group ~53%. Together these account for 191 of the 222 tests with normal classification. From the most frequently used APTT reagents the rate of normal classification is: Patromtin SL (Siemens, n=11) [82%], Actin FSL (Siemens, n=26) [92%], STA APTT / PTT Automate (Stago, n=24) [42%], Platelin LS (Trinity Biotech, n=7) [57%], APTT SP (I.L., n=22) [5%], HemosIL SynthASil (I.L., n=9) [1%]. From the PTT LA users (Stago, n=69) 68% classified the mixing study as prolonged, 2% as borderline and 12% as normal. From the most frequently used DRVVT reagents the rate of normal classification is: LA screen (Siemens, n=8) [53%], LA screen (Life Diagnostics, n=25) [44%], LAC screen (I.L., n=19) [53%], LA Check (Precision Biologic, n=12) [75%], DRVVT screen (Stago, n=23) [39%]. For the KCT assay group (n=31) the percentage of normal classification was ~39%. For the diluted APTT (n=18) and PT group (n=17) this was 5% and ~47%, respectively. Confirmation test In the confirmation test the number of negative classification was 14 (~ 2%). For the APTT assay group this was 23% and for the DRVTT assay group ~18%. From the most frequently used APTT reagents the rate of normal classification is: HemosIL SynthAFax (I.L., n=1) [3%], Actin FS (Siemens, n=21) [33%], Staclot LA (Stago, n=42) [19%]. From the most frequently used DRVVT reagents the rate of normal classification is: DVVconfirm (American Diagnostica, n=27) [37%], LA confirm (Siemens, n=125) [12%], LA confirm (Life Diagnostics, n=32) [16%], LAC confirm (I.L., n=7) [21%], LA Sure (Precision Biologic, n=17) [29%], DRVVT confirm (Stago, n=34) [9%]. In addition, about 21% of the participants in the DRVVT assay group gave a borderline classification. In general there is no clear test combination pattern which is responsible for the negative classification of this sample. This survey shows again that it is difficult to diagnose a weak positive lupus anticoagulant sample. Critical local evaluation of the test panels used is necessary for further improvement.

2 ECAT FOUNDATION EXERCISE 21-3 INTERNATIONAL EXTERNAL QUALITY ASSESSMENT Page 2 of 12 Overview of methods used for lupus anticoagulant testing Screen Mix Confirm Code Description No. No. No. 2 American Diagnostica DVVconfirm American Diagnostica DVVtest American Diagnostica ActiClot dpt AMAX Accuclot drvvt screen AMAX Accuclot drvvt confirm 1 14 BDH Kaolin light 18 Biodata Corporation Platelet extract reagent 1 12 Biopep: LA check 13 Biopep: LA sure 1 96 Dialab APTT-SMA 1 23 Diagen BeA 1 37 Diagen Dia PTT 24 Diagen KPS 112 Diagen Micronised Silica APTT Diagen RVV 119 Diagnostic Lupotek KCT reagent 87 Enzyme Research R2 Diagnostics Haemachrom KCT Haematex SACT reagent Helena BioSciences DRVVT confirm 75 Helena Biosciences DRVVT screen 78 Helena/Ortho Synth. A Fax 89 Hemoliance SynthaFax 79 Hemoliance Synthasil APTT 1 91 Hemoliance Thrombosil 69 Homemade Kaolin Homemade Platelet Lysate Hyphen Biomed Cephen 1LS 1 3 I.L. APTT Lyophilized Silica I.L. APTT SP I.L. HemosIL Recombiplastin I.L. HemosIL Recombiplastin 2G 1 88 I.L. HemosIL SynthASil I.L. HemosIL SynthAFax I.L. LAC confirm I.L. LAC screen I.L. MixCon I.L. PT-Fibrinogen Recombinant 14 I.L. SCT screen I.L. SCT confirm Immuno Dapttin 2 33 Immuno Lupus Anticoagulant Test 12 Kaogen KaoTime Kaolup Confirm Kaolup Screen Kordia LAC kit (Unicorn) 36 Kordia RVV-X C1(rabbit cefaline) 25 Life Diagnostic Gradilin 26 Life Diagnostic Kaoclot Life Diagnostic LA confirm Life Diagnostic LA screen Manchester Diagnostics DRVVT reagents 4 Nycomed Cephotest 41 Nycomed Nycoplastin 1 5 Ortho Recombiplastin 51 Ortho Synthasil

3 ECAT FOUNDATION EXERCISE 21-3 INTERNATIONAL EXTERNAL QUALITY ASSESSMENT Page 3 of 12 Screen Mix Confirm Code Description No. No. No. 8 Precision Biologic LA check Precision Biologic LA sure Precision Biologic Platelet Lysate 7 77 R 2 Diagnostics DRVVT confirm 1 11 R 2 Diagnostics DRVVT screen R 2 Diagnostics LupoTek KCT Renam APTT 74 Renam drvvt confirm 1 73 Renam drvvt screen 71 Renam Erilyrd-Kaolin 72 Renam Renamplastin 19 Siemens Actin Siemens Actin FS Siemens Actin FSL Siemens Innovin Siemens LA1 screen Siemens LA2 confirmation Siemens Pathromtin SL Siemens Thromboplastin C+ 85 Siemens Thromborel R 8 Siemens Thromborel S 7 Siemens ProC Global 1 93 Stago / Roche Cephascreen 2 66 Stago / Roche CKPrest / APTT Kaolin Stago / Roche DRVVT confirm Stago / Roche DRVVT screen Stago / Roche Neoplastin CI Stago / Roche Neoplastin R 67 Stago / Roche Neoplastin Cl Stago / Roche PTT Automate / STA APTT Stago / Roche PTT LA Stago / Roche SPA5 58 Stago / Roche Staclot LA Technoclone Lupus Anticoagulant Test Technoclone LA Screen Technoclone LA Confirm 8 83 Trinity Biotech Accuclot DRVVT confirm 82 Trinity Biotech Accuclot DRVVT screen Trinity Biotech Amax Alexin 13 Trinity Biotech Amax Alexin HS 52 Trinity Biotech APTT 46 Trinity Biotech Automated APTT Trinity Biotech Bioclot LA 1 Trinity Biotech Hemolab Silimat 84 Trinity Biotech Kaolin Trinity Biotech Platelin L Trinity Biotech Platelin LS Trinity Biotech RVV 44 Trinity Biotech Simplastin Trinity Biotech Simplastin HTF 118 Trinity Biotech TriniClot APTT-HS Trinity Biotech TriniClot APTT-S 48 Trinity Biotech Viperquik LA-check 47 Trinity Biotech Viperquik LA-Test 65 Unicorn DRVVT Unichrom LA-DRVVT 116 Vital Diagnostics Vitaclot Unknown

4 ECAT FOUNDATION EXERCISE 21-3 INTERNATIONAL EXTERNAL QUALITY ASSESSMENT Page 4 of 12 Overview ratio ECAT plasma / normal plasma RATIO SCREENING n mean CV Range APTT % APTT SP (IL) % HemosIL SynthASil (IL) % Pathromtin SL (Siemens) % Actin FSL (Siemens) % PTT Automate / STA APTT (Stago) % PTT LA (Stago) % DRVVT % DVVtest (AD) % LAC screen (I.L.) % LA screen (Life Diagnostics) % LA check (Precision Biologic) % LA1 screen (Siemens) % DRVVT Screen (Stago) % KCT % daptt % dpt % Innovin (Siemens) % SCT % Other Remarks: The high CV of the daptt-group and KCT-group in comparison to the other assay groups is remarkable. For the KCT-group this is observed in almost every survey. For the daptt-group this is not the case. RATIO MIXING n mean CV range APTT % APTT SP (IL) % Pathromtin SL (Siemens) % Actin FSL (Siemens) % PTT Automate / STA APTT (Stago) % PTT LA (Stago) % DRVVT % LAC screen (I.L.) % LA screen (Life Diagnostics) % LA1 screen (Siemens) % DRVVT Screen (Stago) % KCT % daptt % dpt % Innovin (Siemens) % SCT Other

5 ECAT FOUNDATION EXERCISE 21-3 INTERNATIONAL EXTERNAL QUALITY ASSESSMENT Page 5 of 12 RATIO CONFIRMATION n mean CV range APTT % Actin FS (Siemens) % PT DRVVT % DVV Confirm (AD) % LAC confirm (I.L.) % LA confirm (Life Diagnostics) % LA Sure (Precision Biologic) % LA2 confirmation (Siemens) % DRVVT Confirm (Stago) % KCT PNP % daptt dpt SCT %

6 > > > ECAT FOUNDATION EXERCISE 21-3 INTERNATIONAL EXTERNAL QUALITY ASSESSMENT Page 6 of 12 LUPUS ANTICOAGULANT (Test plasma 1.57) assay type. other SCT dpt(tti) daptt KCT DRVVT APTT lupus screening APTT DRVVT 6 methods 1 methods other other lupus screening lupus screening SCREENING normal Border line Prolonged your result screening 1 screening 2 screening 3 APTT DRVVT KCT daptt dpt(tti) SCT 17 other For 18 screening tests no classification was given.

7 ECAT FOUNDATION EXERCISE 21-3 INTERNATIONAL EXTERNAL QUALITY ASSESSMENT Page 7 of 12 LUPUS ANTICOAGULANT (Test plasma 1.57) 2 assay type. other 1 SCT dpt(tti) daptt KCT DRVVT APTT lupus mixing MIXING normal Border line Prolonged your result mixing 1 mixing 2 mixing 3 APTT DRVVT KCT daptt dpt(tti) SCT 1 6 other 1 1 For 6 mixing studies no classification was given.

8 > > ECAT FOUNDATION EXERCISE 21-3 INTERNATIONAL EXTERNAL QUALITY ASSESSMENT Page 8 of 12 LUPUS ANTICOAGULANT (Test plasma 1.57) 2 assay type 12 assay type 1. SCT dpt daptt PNP SCT dpt daptt KCT 4 PNP DRVVT PT 2 DRVVT PT APTT APTT lupus confirmation Ratio Screen/Confirm CONFIRMATION Positive Border- Line negative your result confirm 1 confirm 2 confirm 3 APTT PT DRVVT KCT PNP daptt dpt SCT Other 1 RATIO SCREENING/ CONFIRMATION n Mean CV range your result ratio 1 ratio 2 ratio % FINAL CONCLUSION negative Borderline weakly positive positive clearly positive your result

9 ECAT FOUNDATION EXERCISE 21-3 INTERNATIONAL EXTERNAL QUALITY ASSESSMENT Page 9 of 12 ANTICARDIOLIPIN ANTIBODIES Test plasma : 1.57 Type of plasma : Lupus Inhibitor Plasma Low (Technoclone, lot no. 2U1B) Note: Anticardiolipin antibodies were not tested in advance. Former used in exercise : - Number of participants : 433 Responders Number Percentage IgG % IgM % Remarks 1. About 75-8% of the participants reported their results in GPL or MPL units. Only for those category a histogram is reported. 2. Several participants reported a result < [value]. In general the value indicated was included into the statistical evaluations with the exception if the value was 5 or higher. 3. Most of the participants who reported their results in the category Others indicated their results in U/mL. For most of the methods this seems to be the same as GPL or MPL, because the results in both unit categories are comparable. It is highly recommend to report results according to the unit indicated in the kit insert. Overview of methods used for anticardiolipin antibody testing IgG IgM Code Description No. No. 23 Aeskulisa Diagnotic GmbH AIDA 29 Biomed 25 Bio-rad BMD Cardiolisa 3 28 Cambridge Life Sciences Corgenix Reaads Diagnostica Stago Diamedix DiaSorin Inc Euro Diagnostica 219 Euroimmun Genisis Diagnostics Hycor Biomedical IBL 231 Immuno Cocepts RELISA Imtec GmbH INOVA Diagnostics Inc Instrumentation Laboratory IL Acustar Louisville APL Diagnostics Orgentec (Elisa) Orgentec (Alegria) Phadia Pharmacia Diagnostics Varelisa SMC technology 268 The Binding Site Varelisa Vital Diagnostics Homemade Unknown CLASSIFICATION Negative Borderline Low positive Medium positive High positive No conclusion IgG IgM

10 > ECAT FOUNDATION EXERCISE 21-3 INTERNATIONAL EXTERNAL QUALITY ASSESSMENT Page 1 of 12 ANTICARDIOLIPIN ANTIBODIES IgG IgM Anticardiolipin IgG (GPL) Anticardiolipin IgM (MPL) ANTICARDIOLIPIN (IgG) n mean CV range your result Unit: GPL Total Group % Inova % Orgentec (Elisa) % Phadia % Unit: µg/ml Total Group Unit: Other Total Group %.2-28 ANTICARDIOLIPIN (IgM) n mean CV Range your result Unit: MPL Total Group % Inova % Orgentec (Elisa) % Phadia % Unit: µg/ml Total Group Unit: Other Total Group %. 6.9 Remarks: The wide range in reported IgG results in both the GPL and Other unit-group is remarkable. This explains the variation in classification observed.

11 ECAT FOUNDATION EXERCISE 21-3 INTERNATIONAL EXTERNAL QUALITY ASSESSMENT Page 11 of 12 ß2-GLYCOPROTEIN I ANTIBODIES Test plasma : 1.57 Type of plasma : Lupus Inhibitor Plasma Low (Technoclone, lot no. 2U1B) Note: ß2-Glycoprotein I antibodies were not tested in advance. Former used in exercise : - Number of participants : 433 Responders Number Percentage IgG % IgM 98 23% Remarks 1. About 7-75% if the participants reported their results in U. Only for those category a histogram is reported. 2. Several participants reported a result < [value]. In general the value indicated was included into the statistical evaluations with the exception if the value was 5 or higher. 3. Most of the participants who reported their results in the category Others indicated their results in U/mL. For most of the methods this seems to be the same as U, because the results in both unit categories are comparable. It is highly recommend to report results according to the unit indicated in the kit insert. Overview of methods used for ß2-Glycoprotein I antibody testing IgG IgM Code Description No. No. 23 Aeskulisa Diagnotic GmbH AIDA 29 Biomed 25 Bio-rad Corgenix Reaads DiaSorin Inc. 218 Euro Diagnostica Euroimmun Imtec GmbH INOVA Diagnostics Inc Instrumentation Laboratory 236 IL Acustar Orgentec (Elisa) Orgentec (Alegria) Phadia Pharmacia Diagnostics Varelisa SMC Technology 268 The Binding Site Trinity Biotech Varelisa Homemade Unknown 1 5 CLASSIFICATION Negative Borderline Low positive Medium positive High positive No conclusion IgG IgM 96 2

12 > ECAT FOUNDATION EXERCISE 21-3 INTERNATIONAL EXTERNAL QUALITY ASSESSMENT Page 12 of 12 ß2-GLYCOPROTEIN I ANTIBODIES IgG IgM ß2-Glycoprotein I IgG (U) ß2-Glycoprotein I IgM (U) ß2-GLYCOPROTEIN I (IgG) n mean CV range your result Unit: U Total Group %. 14 Inova %. 21. Orgentec (Elisa) % Phadia %. 23. Unit: µg/ml Total Group Unit: Other Total Group % RATIO %.2 9. ß2-GLYCOPROTEIN I (IgM) n mean CV range your result Unit: U Total Group % Inova %. 7.5 Orgentec (Elisa) %.1 5. Phadia % Unit: µg/ml Total Group Unit: Other Total Group % RATIO % Remarks: The wide range in reported IgG results in both the U and Other unit-group is remarkable. This explains the variation in classification observed.