Mom Chandara, Msc, NIPH Team

Transcription

1 Mom Chandara, Msc, NIPH Team

2 EXTERNAL QUALITY ASSESSMENTS (EQAS) EQA refers to a system in which laboratory results are scrutinized objectively by an outside agency in order to get a general impression of the standard of laboratory practice and to achieve inter-laboratory comparability. (Sudarshan Kumari, et. al., 1998)

3 EQAS Program in NIPH Laboraory 2005 NRL (Australia) and NIH Thailand cooparation with CDC organized EQAS workshop at NIPHL March 2005 NIPH Laboratory 1 st EQAS panel were distributed to 19 laboratories in provincial referral hospital (Blood bank) under observation of NRL Australia and NIH Thailand NIPH staff attended on Serum Panel Preparation in NIH Thailand NIPH Laboratory started to produce serum panel

4 Fist Serum Panels in 2005 Serum Panels False Negative False Positive Hbs-Ag 0 1 HCV-Ab 0 0 HIV-Ab1/2 0 0

5 Objective of EQAS HIV serology To expand the implementation of EQAS for HIV serology testing in Cambodia To assess the testing performance and practice of laboratories and To provide assessment data and recommendation to participants that may be used as a tool for continuous improvement of laboratory testing.

6 Methodology NIPH, NCHADS, CDC, and IPC are VCCT core laboratory team to create the SOP for HIV Serology EQAS program. NIPH Prepare Serum Panel, distribute, collected the results, data analyses and write the report. Two reports are distribute one preliminary and final report Provide 2 times per year

7 Methodology Panel status The samples collected from blood donors and used ELISA, Rapid Test, GPA and WB were characterized the samples Prepared 8 samples for 1 st VCCT Panel, include 5 Anti-HIV positive and 3 Anti-HIV negative Among positive samples, 2 samples were duplicated to access testing precision round VCCT Panel were distributed 168 VCCT labs site and deadline period 30days for panel testing. 1 st

8 Expected results of Anti HIV panel tested by organizer s laboratory SAMPLE SAMPLE STATUS EIA (S/Co) RAPID TEST GPA HIV Blot 2.2 (WESTERN BLOT BAND PROFILE) ID. Genscreen Determine Serodi a p17 p24 p31 p39 gp41 p51 p55 p66 gp120 gp160 Interpretation HIVC081-1 Anti-HIV1 Negative NR NR NEGATIVE HIVC081-2 Anti-HIV1 Positive R R POSITIVE HIVC081-3 Anti-HIV1 Positive R R POSITIVE HIVC081-4 Anti-HIV1 Negative NR NR NEGATIVE HIVC081-5 Anti-HIV1 Positive R R POSITIVE HIVC081-6 Anti-HIV1 Positive R R POSITIVE HIVC081-7 Anti-HIV1 Positive R R POSITIVE HIVC081-8 Anti-HIV1 Negative NR NR NEGATIVE NOTE : HIVC081-3 and HIVC081-6 are duplicate samples

9 Reagents used for Panel testing First tests 163 laboratories used Determine HIV ½ 2 laboratories used Serodia HIV 1/2 Second tests 2 laboratories used Determine HIV ½ 117 laboratories used Stat Pak HIV ½ 42 laboratories used Uni-Gold HIV ½ 1 laboratories used BIOTEC HIV ½ 23 laboratories used expired assays for testing 1 st VCCT Panel.

10 Response time Number of Laboratories days days days > 30 days Date of NIPH received results

11 Results Received results back from 165 (98%) VCCT labs Scoring the results as the following: 19 VCCT labs reported 100% (8/8) concordant to reference results 1 VCCT labs reported 87.5% (7/8) concordant to reference results 140 VCCT labs reported 75% (6/8) concordant to reference results 5 VCCT labs reported 62.5% (5/8) concordant to reference results

12 Results No false Positive results 1 laboratory reported false Negative results 4 laboratories reported not precise results on duplicated samples 142 laboratories reported indeterminate results on diluted Positive samples (1 st test Reactive and 2 nd test Non Reaction results).

13 VCCT Serum Panel Test Results for August, 2008 N Lab ID Date Perf HIV C081-1 HIV C081-2 HIV C081-3 Participant's Results HIV C081-4 HIV C081-5 HIV C081-6 HIV C081-7 HIV C081-8 (NR) (R) (R) (NR) (R) (R) (R) (NR) 38 NIPH Neg Pos Pos Neg Pos Pos Pos Neg 39 NIPH Neg Pos IND Neg Pos IND Pos Neg 40 NIPH Neg Pos IND Neg Pos IND Pos Neg 44 NIPH Neg Pos IND Neg Pos IND Pos Neg 45 NIPH Neg Pos Pos Neg Pos Pos Pos Neg 46 NIPH Neg Pos Pos Neg Pos IND Pos Neg 47 NIPH Neg Pos Pos Neg Pos Pos Pos Neg 48 NIPH Neg Pos IND Neg Pos IND Pos Neg 49 NIPH Neg Pos Pos Neg Pos Pos Pos Neg 50 NIPH Neg Pos IND Neg Pos IND Pos Neg 51 NIPH Neg Pos IND Neg Pos NR Pos Neg 52 NIPH Neg Pos Pos Neg IND IND Pos Neg 53 NIPH Neg Pos Pos Neg IND IND Pos Neg 54 NIPH Neg Pos IND Neg Pos IND Pos Neg 55 NIPH Neg Pos IND Neg Pos IND Pos Neg

14 Analyses by Test use Determine HIV ½ Findings 3 labs reported reaction on sample Negative 1 labs reported non reaction on sample Positive 5 labs reported indeterminate on reactive samples Stat-Pak HIV 1/2 4 labs reported reaction on sample Positive 107 labs reported non reaction on samples Positive 4 labs reported indeterminate on reactive samples

15 Analyses by Test use Uni-Gold HIV ½ Findings 13 labs reported reaction on sample Positive 24 labs reported non reaction on sample Positive 4 labs reported indeterminate on reactive samples BIOTEC HIV 1/2 1 lab reported non reaction on samples Positive Serodia HIV 1/2 2 labs reported results concordance to reference results

16 Findings 51 laboratories didn t t submit results on time Some laboratories used expired date assays and one laboratory use assay which did not exist in the list of National Algorithm for HIV ½ testing in VCCT labs. Some laboratories not precisely perform the test on duplicated samples The samples contain low level antibodies which are not good use with some immunocromatography assays.

17 Conclusion Performance of these laboratories clearly expressed the need in order to : Continue the support from the national program To improve quality of testing Thus, NIPH needs to do a close follow-up on corrective actions by the VCCT laboratories.

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