CDC External Quality Assessment/ Proficiency Testing: An experience in 43+ countries

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1 CDC External Quality Assessment/ Proficiency Testing: An experience in 43+ countries Shon Nguyen, B.S, MPH Viral Load and Early Infant Diagnosis Team International Laboratory Branch Division of Global HIV/AIDS CGH/Centers for Disease Control and Prevention

2 Content Overview Quality Assurance Proficiency Testing Program CDC PT program for EID CDC PT program for HIV-1 VL

3 Quality Assurance Activities Quality Assurance (QA) Safety Quality Control (QC) External Quality Assessment (EQA) Record Keeping Other Site Visits Re-testing Proficiency Testing (PT)

4 External Quality Assessment Activities Site Visits Retesting Proficiency Testing A team of supervisors assesses site and provides feedback report for improvement Random selection of clinical samples collected by testing sites and sent to NRL for verification Testing of blinded samples at regular interval by all participants Supervisory Visit All Pos and 10% Neg 5 Samples 2 or 3x/yr

5 Proficiency Testing Process Provider Participants Prepare samples Examine samples Analyze results Report results Prepare report Evaluate

6 Proficiency Testing Benefits Provide early warning for systematic problem Increase confidence in the quality of a laboratory s performance Quality evaluation and improvement of the testing process Demonstrate employee competency As a quality indicator for stakeholders at various levels To monitor trends in results

7 Proficiency Testing Sample Types Sample Type Liquid (Serum/plasma) Dried blood spot (DBS) Dried tube specimen (DTS) Characteristics for PT Requires cold chain transport Risks of spills Expensive Biohazard Transported at room temperature Inexpensive HIV-1 Qual testing for Early Infant Diagnosis (EID) Transported at room temperature Inexpensive HIV-1 RNA Viral Load testing [polymerase chain reaction (PCR) based assays]

8 CDC PT Programs for EID AND VL Voluntary programs Offered free of charge Laboratories actively performing EID/VL testing Each laboratory may enroll more than one testing platform Two or three testing cycles per year

9 Countries participating in CDC PT Programs

10 CDC PT Programs for EID

11 EID PT Panel Package Each PT package consists of 1 sheet of PT Panel (duplicate set of 5 DBS) 1 sheet of Positive Control (10 DBS) 1 sheet of Negative Control (10 DBS) Instructions and Process checklist form

12 EID PT Participants Number of participants CADU NHLS CDC Countries I Number of countries Test Cycle

13 EID PT Participants Number of participants CADU NHLS CDC Countries I Number of countries Test Cycle CDC NHLS CADU PT Countries Laboratories Countries Laboratories Countries Laboratories Event I

14 Improved Performance of Laboratories participated in EID PT Program Garcia et al JCM 2014

15 CDC PT Programs for VL

16 VL PT Panel Package Each PT package consists of Two identical sets of 5 DTS member PT panel One tube of 13 ml of PBS Instructions and processing checklist form

17 VL PT Results Analysis Testing results are compared intra-platform Grading of results is completed if 6 or more results are reported for a given test platform Results grading: limits of acceptability = mean +/- 3 SD Results summary report included both graded and nongraded results All participants receive results report but not all participants receive a graded result

18 Participants and Countries in CDC VL PT Program Countries Participants Number Test Cycle

19 VL PT Participants and Results Number of participants Number of participants unreported results Number of participants reported results % of reported participants with a passing score % of participants with a passing score Test Cycle

20 Improve Performance of Laboratories Participated in CDC VL PT Mean Proficiency Score R² = n= n Number of Cycles Participated

21 Findings Majority of participants score 100% HIV-1 VL PT program using virus stock for DTS provides an excellent quality assurance tool Participants Challenges in Meeting Result TAT (30 days) Ø No reagents Ø Expired kits Ø Instrument in need of repair Ø Long delay in clearing customs

22 Future Directions Ø Improve results TAT and thereby increase results reporting and grading Ø Analysis of PT data to evaluate the HIV programs and provide country guidance Ø Website for CDC PT programs (ept) Ø Evaluate DBS for HIV-1 VL PT for POCT Ø Transfer PT technology to the field

23 Acknowledgements CDC-HQ/ILB John N. Nkengasong, PhD Guoqing Zhang, PhD Rachel S. Beard, PhD Karidia Diallo, PhD Katrina Sleeman, PhD Mackenzie Hurlston, MSPH Stephen Jadczak, BS Artur Ramos, PhD Joy Chang, PhD Chunfu Yang, PhD Vedapuri Shanmugam, PhD Dennis Ellenberger, PhD Carole Moore, MLS John Nahabedian, BS Debrah Boeras, PhD Albert Garcia, MPH Shambavi Subarao, PhD Chin-Yin Ou, PhD Christopher Rasberry, MS Field participants Academic Affairs, Research and Quality Assurance, National Health Laboratory Service (NHLS) South Africa Bacteriology and Virology laboratory, University Cheikh Anta Diop, (CADU) Dakar, Senegal All PT participants who contributed their data included in this report

24 THANK YOU QUESTIONS

25 1. whole blood spiked with known number of 8E5 cells 2. Deliver 100 µl per spot 3. Dry overnight at room temperature 5. Perform validation according to the assay protocol 4. Store in a bag with desiccants and humidity indicator card

26 DTS Preparation and Validation 1. Working solution: add virus stock and green dye to PBS 2. Deliver 20 µl into each tube 3. Dry overnight at room temperature 4. Cap and store at 2-8 o C or -15 o C or colder For validation: Add 1.1 ml of PBS Perform testing immediately or store at 2-8ºC for 24 hrs or -15ºC or colder for up to 1 week Vortex 10 sec

27 DTS Testing 5 DTS specimens One vial of PBS HIV-1 DTS VL PT VL2012-B1 HIV-1 DTS VL PT VL2012-B1 HIV-1 DTS VL PT VL2012-B1 HIV-1 DTS VL PT VL2012-B1 HIV-1 DTS VL PT VL2012-B1 PBS buffer (1x) Open one tube at a time, add 1.1 ml of PBS, Cap tube, vortex 10 sec. Perform testing immediately or store 2-8 o C for 24 hrs or -15 o C or colder for up to one week