The Clinical Laboratory Working with Physicians to Improve Patient Care

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1 The Clinical Laboratory Working with Physicians to Improve Patient Care Michael A. Pesce, PhD Professor Emeritus Columbia University Medical Center Department of Pathology and Cell Biology

2 Objectives Troponin as a Cardiac Bio-marker Classification of troponin assays Contemporary vs high sensitivity Troponin assays Developing an algorithm for using high sensitivity troponin assays The role of HIV testing in labor and delivery Developing an algorithm in testing and reporting of HIV results in L&D

3 Troponin Characteristics Troponin C (18 kd) Calcium-binding subunit Troponin I (26.5 kd) Actomyosin-ATP-inhibiting subunit Troponin T (39 kd) Tropomyosin-binding subunit Ca 2+ troponin complex TnC TnI TnT actin tropomyosin The troponin complex consists of three different proteins (TnC, TnI, and TnT) that regulate the calcium-mediated contractile process of striated muscle.

4 Tissue Specificity of Troponin Subunits Troponin C is the same in all muscle tissue Troponin I and Troponin T are detected in heart muscle and are cardiac specific Circulating concentrations of ctni and ctnt are very low ctni and ctnt remain elevated for several days The false-positive CKMB results that are due to skeletal muscle involvement should be eliminated with use of the Troponin assays.

5 Specificity of ctnl, CK-MB Mass & Myoglobin In Noninfarct Patients with Chronic Renal Failure or Severe Polytrauma Pathology No. (%) of Specificity & Markers Positive Sera % Severe Polytrauma (24 Sera) CK-MB mass 14(58) 42 Myoglobin ctnl 21(88) 0 (0) Chronic Renal Failure (49 Sera) CK-MB mass 4 (8) 92 Myoglobin 43(88) 12 ctnl 0 (0) 100

6 Classification of Myocardial Infarction Type I MI - Spontaneous myocardial infarction related to ischemia due to a primary coronary event such as plaque erosion and/or rupture, fissuring, or dissection - Type II MI - Myocardial infarction secondary to ischemia due to either increased oxygen demand or decreased supply - Type III MI - Sudden unexpected cardiac death, including cardiac arrest, often with symptoms suggestive of myocardial ischemia - Type IV MI Associated with PCI/stent thrombosis - Type V MI - Associated with CABG

7 Third Universal Definition of Myocardial Infarction To diagnose Type 1 or Type 2 MI, a blood sample must detect a rise or fall Troponin I or T, with at least one value above the 99th percentile with at least one of the following : Symptoms of ischemia New ST-segment or T-wave changes or new left bundle branch block Development of pathologic Q waves Imaging evidence of new loss of viable myocardium or new wall-motion abnormality Finding of an intracoronary thrombus by angiography or autopsy.

8 Importance of Serial Sampling in the Detection of AMI Allows for differentiation of acute versus chronic troponin elevation No agreement on what the frequency of troponin testing should be AHA Guidelines 0, 6,12 hours. Universal Definition of MI 0, 3, 6 hours, European Society of Cardiology 0, 6. 9 hours. JACC vol 61 No European Heart Journal June 2010.

9 Elevations of Troponins without Overt Ischemic Heart Disease Trauma (including contusion, endomyocardial biopsy, cardiac surgery) Congestive heart failure acute and chronic Hypertension Hypotension, often with arrhythmias Postoperative noncardiac surgery patients who seem to do well Renal failure Myocarditis Post PCI patients who appear to be uncomplicated Pulmonary embolism Sepsis Burns, Amyloidosis Acute neurological disease, including CVA Rhabdomyolysis with cardiac injury Source: A. Jaffe, MD

10 Detection Range of Different ctn Assays AM Heart J 2010;160:583 94

11 Comparison of Two Troponin I assays TNI Cutoff,ug/L Siemens Siemens Ultra original >0.04 >0.1 Baseline Sample Sensitivity 74(59-85) 55(40-69) Specificity 84(79-87) 93(89-95) Follow up Sample Sensitivity 94(83-99) 86(73-94) Specificity 81(77-86) 90(87-93) Tn cutoffs > 99% of reference control group and 10% CV at that level

percentile of a normal population but use the Troponin concentration where

12 Interpreting Troponin Results Troponin results greater than the Upper Limit of Normal (ULN) indicates cardiac damage ULN is defined as the 99 th percentile of a normal population but use the Troponin concentration where your lab s assay can reproducibly measure levels with total imprecision of 10% CV

13 Contemporary Cardiac Troponin Assays Table 1. Analytical characteristics of contemporary sensitive cardiac troponin assays. Cardiac troponin concentration at: Amino acid residues of epitopes 99th Percentile, 10% CV recognized by capture (C) and Company/platform/assay LoD,a (CV)b concentration, L detection (D) MAbs Abbott ARCHITECT (14%) C: 87 91, 24 40; D: Beckman Access AccuTnI (14%) 0.06 C: 41 49; D: biomé rieux Vidas Ultra (27.7%) 0.11 C: 41 49, 22 29; D: 87 91, MAb 7B9 Ortho Vitros ECi ES (10%) C: 24 40, 41 49; D: Response RAMP 0.03 <0.01 (18.5% at 0.05) 0.21 C: 85 92; D: Roche Elecsys TnT Gen < C: ; D: Roche Elecsys TnI (10%) 0.30 C: 87 91, ; D: 23 29, Siemens Centaur Ultra (8.8%) 0.03 C: 41 49, 87 91; D: Siemens Dimension RxL (20%) 0.14 C: 27 32; D: Siemens Immulite (NA) 0.42 C: 87 91; D: Siemens Stratus CS (10%) 0.06 C: 27 32; D: Siemens Vista (10%) 0.04 C: 27 32; D: Tosoh AIA 0.06 <0.06 (NA) 0.09 C: 41 49; D: a LoD, limit of detection; NA, not available; Gen 4, fourthgeneration assay. b CV at 99th percentile. Clin Chem 58: (2012)

14 Definition of hs troponin assays The CV should be less than or equal to 10% at the 99 percentile. The assay should measure troponin levels in at least 50% of a healthy population Sex specific cutoffs should be established Values should be reported in ng/l

15 Normal Range

16 hs Troponin Assays Table 2. Analytical characteristics of hs cardiac troponin assays. Cardiac troponin concentration at: Amino acid residues of epitopes Company/ 99th Percentile, 10% CV recognized by capture (C) and platform/assay LoD,a ng/l ng/l (CV)b concentration, ng/l detection (D) MAbs hs-ctni Abbott ARCHITECTd (5.6%) 3.0 C: 24 40; D: Beckman Accessc (10%) 8.6 C: 41 49; D: Nanosphere MTPc (9.5%) 0.5 C: ; D: MAb PA1010 Singulex Erennac (9.0%) 0.88 C: 41 49; D: Siemens Vistac (5.0%) 3 C: 30 35; D: 41 56, hs-ctnt Roche Elecsysd (8%) 13 C: ; D: a LoD, limit of detection; MTP, microtiter plate. b CV at the 99th percentile. c Under development and not available for commercial use. d Available for use worldwide but not cleared by the US Food and Drug Administration for use in the US. Clin Chem 58: 1, (2012()

17 High Sensitivity Cardiac Troponin T 1 hr Protocol Patients presenting to the ED with symptoms suggestive of acute myocardial infarction (such as acute chest pain and angina pectoris) with an onset or maximum discomfort or pain within the previous 6 hours were included in this study. There was 1282 patients, average age 62 years, 184 diagnosed with an AMI. There were 805 men and 477 women. Diagnosis for each patient was performed by several cardiologists. Annals of Emergency Medicine 2015

18 Criteria for Using hs Troponin T using an 1 hr algorithm

19 Performance of the 1 hr hs troponin T assay

20 Issues to be Decided Before Using High Sensitivity Troponin Assays Report cutoff values for AMI using the 99 percentile not the value at 10% CV Report troponin values in ng/ L Establish reference range for men and women Validate the assay

21 Issues to be Decided Before Using High Sensitivity Troponin Assays Develop an algorithm for using hs troponin assays to detect acute AMI Input by Cardiologists, Internists, ED, Pathologists and Laboratory Scientists Define time intervals for drawing blood Define Troponin levels that will rule in or rule out AMI Define AMI using absolute differences between the Troponin levels taken between the 0 and 1 or 2hr interval

22 Issues to be Decided Before Using High Sensitivity Troponin Assays Define critical troponin value and how it should be reported Define the criteria for differentiating AMI from cardiac damage from noncardiac causes Establish TNT for reporting result

23 Rapid HIV Testing in Clinical Practice: Labor and Delivery - According to the CDC: Mother-to-child transmission of HIV can occur during pregnancy, during labor and delivery, and post-partum, with breastfeeding as the only important mode of postnatal transmission. The majority of the mother-to-child transmission cases, approximately 60-70%, occur during labor and delivery approximately 40% of the mothers of the HIV infected infants did not know that they were HIV positive.

24 CDC Facts The Numbers HIV and AIDS Diagnoses Approximately 8,500 women living with HIV give birth annually. Most (73%) of the estimated 174 childrena in the United States who were diagnosed with HIV in 2014 got HIV through perinatal transmission. Most (88%) of the estimated 104 children in the United States diagnosed with AIDS in 2014 got HIV through perinatal transmission. Living With HIV Of the estimated 1,999 children living with perinatal HIV at the end of 2013, 1,298 (65%) were black/african American, 312 (16%) were Hispanic/Latino,b and 212 (11%) were white. At the end of 2013, an estimated 9,131 adults and adolescents (aged 13 and older) were living with HIV acquired through perinatal transmission. Of these, 60% (5,495) were black/african American, 23% (2,093) were Hispanic/Latino, and 12% (1,118) were white. Deaths An estimated 4,998 children ever diagnosed with AIDS have died since the beginning of the epidemic through the end of 2013 (includes only those under age 13 at time of death).c Almost all of them (91%) got HIV through perinatal transmission

25 Perinatal HIV Transmission 1. Without ARV drugs during pregnancy, risk of transmission from mother to infant is 1 in 4 2. In 1994 the Pediatric AIDS Clinical Trials Group (PACTG) 076found that by giving antiretroviral therapy to HIV infected women perinatally, and to their newborns in the first few weeks of life, the transmission rate of HIV was reduced from 25.5% to 8.3% (N Engl J Med. 1994;331: ).

26 HIV Prevention In the mid 1990 s approximately 1700 children were born infected with HIV. Now the risk of perinatal transmission can now be less than 1%(1 in 100) with: Highly effective ARV therapy (HAART) Elective Cesarean section (C/S) Formula feeding

27 Rapid HIV Testing In 1999, New York State Department of Health mandated that the turnaround time for reporting HIV results from Labor and Delivery be no longer than 48 hours from the drawing of blood from the mother or from the newborn. As a result, the rate of perinatal HIV transmission in New York State decreased from 10.9% in 1997 to 3.9% in 2001.A shorter turnaround time was needed, but was limited by the EIA methodology that was available for measuring HIV. In 2002, the FDA approved a rapid whole blood HIV test. In November 2003, New York State Department of Health mandated that the turnaround time for reporting of HIV results from Labor and Delivery be no longer than 12 hours after the specimen is drawn. The only way that Hospitals could comply with the New York State regulations was to measure HIV with a rapid assay.

28 Issues to be Resolved before Offering HIV testing in Labor and Delivery Should there be POC testing for HIV in Labor and Delivery? Input by pediatricians, infectious disease physicians, obstetricians, nurses, laboratory director How to order the correct HIV test Transporting the specimen to the laboratory

29 Issues to be Resolved before Offering HIV testing in Labor and Delivery Should rapid HIV testing be measured in the main lab? What rapid HIV test should be used? Validate the rapid HIV assay Reporting of HIV results

30 Reporting of HIV Results from L&D All positive HIV results are reported as preliminary positive in our HIS and are called to: Labor and Delivery chief resident Pediatric chief resident Infectious disease attending All preliminary positive HIV results are confirmed Negative HIV results are not called The time that the HIV specimen was drawn, received in the lab and the time that the result is reported is logged into the HIS system

31 Labor and Delivery-HIV Testing at NYPH TNT ranged between 1-25 hours 99% of results were reported within 12 hours after drawing the specimen

32 Conclusion The laboratory staff needs to interact with the medical staff (physicians, nurses, administrators) and use our expertise in laboratory medicine to provide better service to the patient and physicians who are our customers.

Use of Biomarkers for Detection of Acute Myocardial Infarction

Use of Biomarkers for Detection of Acute Myocardial Infarction Allan S. Jaffe, MD.* Consultant - Cardiology & Laboratory Medicine Professor of Medicine Chair, CCLS Division, Department of Laboratory Medicine