Presentation on theme: "CDD Updates on Specimen Collection & Processing"— Presentation transcript:
1CDD Updates on Specimen Collection & Processing Mohammad Al-GhoulJoe LyonsMarian Tully
2Center for Disease Detection Mohammad Al-GhoulCenter for Disease Detection
3Agenda New tests implemented by CDD New HIV testing algorithm 4th generation HIV testHIV-1/HIV-2 Discriminatory assay (Multispot test)CT/GC testing using cobas 4800 systemToxicology testing process and test changesRecent changes with CDD processes and tubes usedTips for optimal sample collectionList of tests availableQ & A
4HIV New Testing Algorithm Advantages of using the fourth generation HIV assayAdvantages of using the HIV-1/HIV-2 Discriminatory assay (Multispot test)Explain the new testing algorithm
54th Generation HIV Assay FDA-approved in June 2010The first diagnostic assay that:Detects HIV antibodies and HIV-1 p24 antigenCan be used on children ≥ 2 yearsA new testing algorithm that replaces WB test with MultispotAbility to Detect HIV Infection Earlier
64th Generation HIV Assay Detects Infection in Acute Phase Acute retroviral symptomsHIV RNAHIV Abs0-11 days,Infection Undetectable:No tests to close the gap4th generation improvement11-22 daysHIV p24 AgTo consider efficacy of current HIV detection methods, we must understand that acute infection or the diagnostic window is defined as the interval from the initial infection to the time that the antibody to HIV is detectable. Viral Load testing by HIV RNA or other NAAT testing method is the most sensitive test method. At the time of infection until about 11 days post-infection, HIV RNA would not be detectable in the patient’s plasma. This window cannot be closed with current technology. On average, about 5 days later (or Day 16), p 24 Ag would be detected in patient serum. After about three weeks, Ab would be detected in patient serum.In summary, while the WB method was more sensitive at the time of implementation of the CDC/APHL testing algorithm in 1989, WB is actually less sensitive than the third and fourth generation HIV assays (with WB blot detection occurring at about 4 weeks). The 4th generation assay improves the diagnostic window and is capable of detecting infection within 5 days after Viral Load by HIV RNA or other NAAT testing.10203040168111622(Days)Viral Load by HIV RNA or other NAAT4th – generation (p24 Ag+Ab Combination) EIAHIV Antibody 3rd gen50% of new HIV infections acquired from persons with Acute HIV Infection (Day 0 – Day 20)
7Advantages of 4th Gen. Assay Detects HIV-1/-2 antibodies and HIV-1 p24 antigen simultaneouslyIdentifies HIV infection 2-20 days earlier than HIV antibody tests aloneDetects acute, as well as latent infections using a time and cost-saving strategy.The p24 antigen is produced during the first few weeks and is detectable 7-9 days earlier than the appearance of HIV antibodies. As a result, the p24 antigen is an ideal marker to aid in early HIV diagnosis.
8Western Blot Vs. Multispot HIV-1 Positive: Preliminary positive for HIV-1 AbHIV-1 Negative: No Ab detected for HIV-1Indeterminate: Repeat testing or collect another specimen and send for NAAT testingHIV-1 Positive: Preliminary Positive for HIV-1 Antibodies and HIV-1 P24 AgHIV-2 Positive: Preliminary positive for HIV-2 antibodiesIndeterminate: Collect another specimen and send for NAAT testingHIV Positive (Undifferentiated) Additional testing recommended
9Limitations of Current Algorithm Antibody tests do not detect infection in ~10% of infected persons at highest risk of transmissionCannot detect acute infections and misclassifies approximately 60% of HIV-2 infections as HIV-1, based on HIV-1 WB results.Three day turnaround time for confirmationbecause infected persons may not learn their test results and become lost to follow upDetection of Acute HIV Infection in Two Evaluations of a New HIV Diagnostic Testing Algorithm — United States, 2011–2013, CDC, MMWR June 21, 2013 / 62(24);
10Characteristics of an Ideal HIV Diagnostic Algorithm Detects HIV acute and latent infectionsDifferentiates HIV-1 from HIV-2Eliminates indeterminate results due to cross reactivity of HIV-2 Ab with HIV-1 WBReduces the diagnostic windowFaster turnaround times
11New HIV Diagnostic Algorithm A1: 4th generation HIV-1/2 immunoassayA1+A1(-)Negative for HIV-1 and HIV-2 antibodies and p24 AgRepeat in duplicateA2: HIV-1/HIV-2 differentiation immunoassay (Multispot)HIV-1 +HIV-1 antibodies detected Initiate careHIV-1&2 (-)HIV-2 +HIV-2 antibodies detected Initiate careRNARNA Acute HIV-1 infection Initiate careRNA (-) Negative for HIV-1Proposed in March 2010CDC APHL HIV Diagnostic conference
12Conclusion Earlier detection of infection Differentiation between HIV-1 and HIV-2Faster turnaround times for reports
13Agenda New tests implemented by CDD New HIV testing algorithm 4th generation HIV testHIV-1/HIV-2 Discriminatory assay (Multispot test)CT/GC testing using cobas 4800 systemToxicology testing process and test changesRecent changes with CDD processes and tubes usedTips for optimal sample collectionTest ListQ & A
14CT/GC Testing: New Methodology The cobas 4800 system recently approved by the FDA to test for HPV and CT/GCIncreased Sensitivity/SpecificityProvides inhibitory control
15CDC Screening Recommendations CT/NG Specimen Types Vaginal swabs: preferred specimen type for testing using NAATUrine: preferred specimen type for testing males using NAATSexually Transmitted Diseases Treatment Guidelines, 2010; CDC, December 17, 2010
16Testing for CT/GC by the Following Vaginal Swab (Clinical Setting)Collector Stability (RT 365 days)UrineCollector Stability (RT 365 day)PreservCyt (ThinPrep)Collector Stability (RT 21 days)Coming Soon:Endocervical SwabCT/GC results are reported within 24 hours of specimen receipt
17Vaginal Swab Rejection Criteria 10%5%2.5%No BloodReject cobas® vaginal swab specimens for CT/NG testing if the whole blood concentration is >10.0% (dark red or brown coloration).
18Urine Rejection Criteria 0.35%0.175%0.083%No BloodReject cobas® Urine specimens for CT/NG testing if whole blood concentration is >0.35%.
19PreservCyt (ThinPrep) Rejection Criteria 1.5%0.75%0.037%No BloodCompare PreserveCyt® specimens to the images above.Reject specimens for CT/GC testing if whole blood concentration is >1.5%.
20Agenda New tests implemented by CDD New HIV testing algorithm 4th generation HIV testHIV-1/HIV-2 Discriminatory assay (Multispot test)CT/GC testing using cobas 4800 systemToxicology testing process and test changesRecent changes with CDD processes and tubes usedTips for optimal sample collectionTest ListQ & A
21Reliability and Validity of Urine Toxicology Specimen More than 70% of lab errors are due to specimen collection issues
22Urine Drug Testing Limitation Urine drug testing only indicates prior useNot useful for determining:Time since last useExtent/frequency of useAdditional use since last positive testCurrent impairment
23Testing Methods Screening: Enzyme Immunoassay (EIA) Confirmation: Gas Chromatography/Mass Spectrometry (GC/MS)“Gold-Standard” for Drug TestingNO BIOLOGICAL FALSE POSITIVES
24Test Menu and Turnaround Times Job Corps Toxicology PanelAMP/Meth-AMP Panel (72h)Cannabinoids (48h)Cocaine (48h)Opiates (72h)PCP (48h)NEWToxicology orders now have their own accession numbers.Discuss theNegative screening results are released the same day the specimen is received at CDD
25Spice/K2K2 or Spice is a mixture of herbs, spices or shredded plant material that is typically sprayed with a synthetic compound chemically similar to THCAt least 41 states and Puerto Rico have legislatively banned synthetic cannabinoids
26John W. Huffman, PhD "People who use it are idiots.” JWH-018JWH-133"People who use it are idiots.”"You don't know what it's going to do to you."
27Spice Test (Synthetic Cannabinoids) Current test detects three metabolitesJWH-018 M5JWH-018 M6JWH-073 M6
28New Spice Test Screening Confirmation for 16 separate metabolites Detected / Non detectedConfirmation for 16 separate metabolitesAM2201, AM694, JWH 018, JWH 019, JWH 073, JWH 081, JWH 122, JWH 203, JWH210, JWH 250, JWH 398, MAM 2201, RCS-4, 2XUR-144, XLR11
29Agenda New tests implemented by CDD New HIV testing algorithm 4th generation HIV testHIV-1/HIV-2 Discriminatory assay (Multispot test)CT/GC testing using cobas 4800 systemToxicology testing process and test changesRecent changes with CDD processes and tubes usedTips for optimal sample collectionTest ListQ & A
30Center for Disease Detection Joe LyonsCenter for Disease Detection
32Blood Collection Devices 7.5 mL Tiger TopNo Fill Line MarkAdditive – serum clot activator
33Blood Collection Devices 10% AboveFill Mark10% Below4 mL SST and Red TopAdditive – serum clot activator
34Blood Collection Devices 3 mL Purple TopCBC, H/HSample Fill LineAdditive - Ethylenediaminetetraacetic acid (EDTA)10% AboveFill Mark10% Below
35Urine Collection Devices Yellow TopTOX and NY CT/GCSample fill lineNo AdditiveNo fill requirement other than amount necessary to run testFill Mark
36Urine Collection Devices Do Not Exceed this lineRed and Yellow TopSample fill lines (stay within lines)Additive – urine preservativeDo Not fill lower than this line
37Urine Collection Devices cobas® PCR Urine collectorSample fill lines (stay within lines)Additive – PCR mediaA drop DOES NOT make a differenceDo not exceed this lineDo not fill lower than this lineMention that we have seen people using the temperature gauge as a fill line and filling to the small area between the arrow and fill line.
38Swab Collection Device cobas® PCR Female SwabPatient collectedSample fill lines NOT usedAdditive – PCR mediaDiscard extra swabSwab down (bacteria in media)
39The best result begins with the SPECIMEN Women – Vaginal specimenMen – Urine SpecimenDoes not require use of the cleaning swabDiscard one swabInsert one swab approximately 2 inches into the vaginaGently turn the swab for about 30 seconds while rubbing the swab against the wall of the vaginaRemove swab and place into the cobas® PCR media tubeBreak shaft at etch mark and recap tubeNote: Swab must be at bottom of tubePatient should not urinate 1 hour prior to samplingCollect urine at the beginning of the urine stream. This is not a mid- stream collection.Collect first 10 to 50 mL of urine, additional volume may begin to dilute the specimenTransfer appropriate volume of urine to the cobas® PCR media tubeWe have full collection instructions that are available from your account manager.
40Phlebotomy TipsPlace arm in a downward position.
41Phlebotomy TipsUse an insertion angle of 10 to 20 degrees.
42Phlebotomy TipsA frequent cause of no blood flow is that the tip is no longer in the vein lumen.
43Phlebotomy Tips Make a fist, do not pump (pumping increases potassium) Avoid tapping the venipuncture siteWarm the venipuncture siteWait an extra few seconds when it appears blood flow has stoppedEnsure all additive tubes are gently rocked 8-10 times
44Phlebotomy Tips To avoid Hemolysis Do not apply tourniquet too tightly or for too long.Do not shake the sample instead gently rock it 8-10 times.Do not delay separation of cells from serum by centrifugation(>3 hours)Too long or too high centrifugation
45Agenda New tests implemented by CDD New HIV testing algorithm 4th generation HIV testHIV-1/HIV-2 Discriminatory assay (Multispot test)CT/GC testing using cobas 4800 systemToxicology testing process and test changesRecent changes with CDD processes and tubes usedTips for optimal sample collectionTest ListQ & A
46Center for Disease Detection Marian TullyCenter for Disease Detection