NIBSC Multiplex Proficiency Panel - A multicentre study Clare Morris and David Padley Divisions of Retrovirology and Virology

Panel History Panels produced for the UK National Blood Transfusion Authority. UK requirement to screen for HCV RNA in blood donations since 1999. Initially, annual HCV proficiency panels produced to monitor assay and operator performance across UK sites. In 2005 HIV-1 screening introduced in the one NBS site. 1st HIV-1 RNA Proficiency panel produced in 2006. Panels have consisted of dilutions of a single marker, up to 15 members/panel.

New multiplex approach Panel consisted of 15 coded samples. Contained combinations of HIV, HCV, HBV. One plasma negative was included. 7 labs took part, 2 labs reported data using two systems. Due to potential for confirmatory testing each lab was sent 4 panels. Requested to test panel through routine algorithm. 5 labs used commercial assays, 2 used in house assays Biomerieux Amplicor Procliex Ultrio In house 1 3 2

Panel Details Sample number Sample Concentration 1 HCV 100IU 2 50IU 3 4 HIV-1 200IU 5 6 7 Negative plasma 8 HIV-1, HCV, HBV 200IU, 100IU, 50IU 9 100IU, 50IU, 20IU 10 HCV + HIV 50IU + 200IU 11 20IU + 100IU 12 HCV + HBV 13 50IU + 50IU 14 HIV + HBV 200IU + 100IU 15 100IU + 50IU

- + 4a 4b 7a 7b HIV-1 Results Not tested for HIV Reactive LAB Sample 1 HCV 2 3 4 HIV 5 6 7 NEG 8 HCVHBV 9 10 HCV + HIV 11 12 HCV + HBV 13 14 HIV + HBV 15 LAB - + Not tested for HIV 4a 4b 7a Reactive 7b

4a 4b 7a 7b HCV Results + - Reactive LAB Sample 1 HCV 2 3 4 HIV 5 6 7 NEG 8 HCVHBV 9 10 HCV + HIV 11 12 HCV + HBV 13 14 HIV + HBV 15 LAB + - 4a 4b 7a Reactive 7b

+ 4a 4b 7a - 7b HBV results Not tested for HBV Reactive LAB Sample 1 HCV 2 3 4 HIV 5 6 7 NEG 8 HCVHBV 9 10 HCV + HIV 11 12 HCV + HBV 13 14 HIV + HBV 15 LAB + Not tested for HBV 4a 4b 7a Reactive - 7b

Conclusions HIV: One lab didn’t detect 100IU in triplex sample. All other labs detected HIV at all concentrations. HCV: Lab 2 failed to detect 20 IU sample. Lab 6 failed to detect 10 IU sample & 100 IU in a triplex sample. HBV: 3 data sets available. All HBV samples detected. 50 proficiency panels remaining, if you would like to receive one please E mail me at: Clare.Morris@nibsc.hpa.org.uk