for Microbiology Quality Assessment Programmes for HPV and MRSA Effect of change to assessment categories for HBV DNA Dr Vivienne James SoGAT 2009

Transcription

1 for Microbiology Quality Assessment Programmes for HPV and MRSA Effect of change to assessment categories for HBV DNA Dr Vivienne James

2 Overview Update on the HPV scheme introduced in 2009 MRSA screening scheme Performance assessment of HBV quantification

3 Molecular HPV EQA Scheme - Update Three distributions of four cervical specimens in PreservCyt are dispatched annually with a request for determination of the presence or absence of high risk human papilloma virus (HPV) and the genotypes present.

4 HPV detection methods used (May 2009) PreTect HPV-Proofer, 1 In-house PCR, 3 Other, 4 Digene: Hybrid Capture 2, 12 Roche: Amplicor, 4 Genomica, 5 Roche: Linear Array, 5 Innogenetics:InnoLiPa, 5

5 Unspecified Other Roche: Amplicor Roche: Linear Array Innogenetics:InnoLiPa PCR: Single target Real-Time Single Sequencing Digene: Hybrid PreTect HPV-Proofer Genomica Unspecified Other Roche: Amplicor Roche: Linear Array Innogenetics:InnoLiPa PCR: Single target Real-Time Single Sequencing Digene: Hybrid PreTect HPV-Proofer Genomica Unspecified Other Roche: Amplicor Roche: Linear Array Innogenetics:InnoLiPa PCR: Single target Real-Time Single Sequencing Digene: Hybrid PreTect HPV-Proofer Genomica Unspecified Other Roche: Amplicor Roche: Linear Array Innogenetics:InnoLiPa PCR: Single target Real-Time Single Digene: Hybrid PreTect HPV-Proofer Genomica Results reported (2473) n= HR negative genotypes 39 and 53 genotype 31 genotypes 16 and 39 Negative Positive

6 Unspecified Real-Time Single Genomica PCR: Single target Other Real-Time Single Digene: Hybrid PreTect HPV- Roche: Amplicor Roche: Linear PCR: Single target Digene: Hybrid PreTect HPV- Digene: Hybrid Incorrect results by method HR negative genotypes 39 and 53 genotype 31 genotypes 16 and 39

7 Genotyping methods used Sequencing, 2 In-house PCR, 2 Other, 3 Roche: Linear Array, 11 Genomica, 5 Innogenetics: InnoLiPa, 6

8 Negative Number of reports Genotype results Genomica Sequencing Real-Time Single target PCR: Single target Innogenetics:InnoLiPa Roche: Linear Array Other Unspecified 0 Negative Genotype combinations reported Intended result

9 HPV Summary 55 specimens sets were dispatched; 44 participants responded (8 UK); 40 datasets Correct detection results were reported by 31 to 39 participants 6 commercial assays; 3 providing genotyping results Up to 29 participants reported genotype results Variations in the genotypes reported by participants using assays from the same manufacturer

10 MRSA screening Patients colonized with MRSA contribute to increased prevalence MRSA bacteraemia rates correlate with MRSA hospital prevalence Active screening of patients for MRSA colonisation Targeted approach to the use of isolation facilities Containment of MRSA nosocomial dissemination

11 Importance of the scheme High throughput of MRSA specimens in routine diagnostic labs High degree of variability in practice Number of different methods available Novel techniques

12 MRSA screening scheme Annually, 6 distributions each containing 2 specimens Suitable for both conventional and molecular methods Development of simulated swab to represent environmental swabs

13 MRSA molecular methods BD GeneOhm Cepheid Xpert Hain Real time multiplex other Real time single target PCR multiplex

14 MRSA screening results

15 HBV DNA quantification Monitor active infection Monitor patients response to therapy Infectivity of Health Care Workers

16 HBV DNA quantification scheme Introduced as accredited scheme in 2003 Annually includes 2 distributions each containing 4 specimens Reports present data on the viral load by method (number, range, median, CI) Scoring based on the median difference in viral load between the specimen pair Clinically relevant: monitoring response to therapy Assesses participants performance Avoids bias due to differences in absolute values obtained with different manufacturers kits In-house assays can be included in the analysis

17 However. Development of treatment algorithms Assessment of healthcare worker status Improvements in comparability between methods Should assessment be qualitative?

18 Development of treatment algorithms Recommendations for Treatment: HBeAg-Positive CHB HBV DNA IU/mL ALT Treatment < Normal No treatment Monitor status > Normal Liver biopsy, treat if disease, monitor ALT > Elevated Entecavir, tenofovir &/ or peginterferon

19 Development of treatment algorithms Recommendations for Treatment: HBeAg-Negative CHB HBV DNA IU/mL ALT Treatment <2 000 Normal No treatment Monitor status >2 000 Normal Liver biopsy, treat if disease, monitor ALT >2 000 Elevated Entecavir, tenofovir &/ or peginterferon Long-term treatment required for oral agents

20 Development of treatment algorithms Recommendations for Treatment: Patients With Cirrhosis HBV DNA IU/mL Cirrhosis Treatment <2 000 Compens. Treatment or monitor status Entecavir or tenofovir >2 000 Compens. Entecavir or tenofovir or combination therapy. Long term treatment Any detectable Decomp. Combination with lamivudine or Entecavir plus tenofovir Long term treatment Liver transplantation

21 Retrospective analysis of the affect of the change Specimen No. datasets Mean SD Median Minimum Maximum Category > > to <2 000 No. below No. above 5 6 % correct 99% 99% 85% 94% Current score 90% 93%

22 HBV quantification summary Participant performance assessment will be reviewed in the light of new treatment algorithms for HBV Is a qualitative assessment sufficient? Should we still encourage precision in results? Presentation of results of the viral load by method (number, range, median, CI)

23 Acknowledgements Staff and participants of UK NEQAS for Microbiology Royal Infirmary Edinburgh: Heather Cubie Catherine Moore HPA: Cath Arnold Angela Kearns