Investigation of an algorithm for anti HCV EIA reactivity in blood donor screening in Turkey in the absence of nucleic acid amplification screening

Comparative evaluation of the Geenius HCV supplemental assay and Inno-LIA HCV score assay in detecting anti-HCV antibodies

OBJECTIVE

This study compared two assays aimed at confirming the presence of anti-HCV antibodies (Ab) after a positive screening: Geenius HCV supplemental assay (Bio-Rad, Marne la Coquette, France) and the Inno-LIA HCV score assay (Fujirebio, Les Ulis, France).

MATERIAL AND METHODS

A total of 180 archived samples were investigated including 119 samples collected at different stages of HCV infection in 25 hemodialyzed patients who underwent HCV seroconversion, 14 samples from 4 commercial seroconversion panels, 47 Ab positive/HCV-RNA positive blood donations of which 7 showing an single reactivity in confirmatory assays. Samples were investigated and results were interpreted with the two assays according to the manufacturers' instructions.

RESULTS

Overall, Geenius and Inno-LIA were concordant for 84% (151/180) samples: 38 negative, 17 indeterminate and 96 positive. Of the 29 discrepant results, 26 were overclassified with Inno-LIA. HCV seroconversion was detected with Inno-LIA 4 and 7 days prior to Geenius in two panels. The high positive rate observed with Inno-LIA (64%) compared to Geenius (54%) was mainly due to low reactivities considered positive according to interpretation criteria, which could affect specificity.

CONCLUSION

Although HCV supplemental assays are not recommended for the diagnostic of HCV infection, which is primarily based on HCV-RNA testing, both assays are suitable as second line anti-HCV tests when Ab screening is positive and RNA testing cannot be performed. Moreover, Geenius system provides an objective result in less than 30minutes, which is compatible when a rapid diagnostic is required.

Metaanálisis de la validez y el desempeño de las pruebas de tamización del virus de la hepatitis C en bancos de sangre, 2000-2018

Este estudio evaluó la validez y desempeño del inmunodiagnóstico del virus de la hepatitis C (VHC), con base en estudios publicados en la literatura científica mundial. Se diseñó y validó un protocolo de búsqueda y selección de investigaciones en las fases de la guía PRISMA, se analizaron los parámetros de sensibilidad, especificidad, cocientes de probabilidad, razón de odds y curva ROC, en MetaDisc. Se tamizaron 4602 estudios, de los cuales sólo 545 se realizaron en bancos de sangre y 18 evaluaron la validez diagnóstica de las pruebas para el VHC. La mayoría de los estudios fueron de Europa y Asia, con un 78 % basados en determinación de anticuerpos. Los estudios con detección de anticuerpos se realizaron en 21 483 donantes sanos y 3 145 infectados en quienes se halló una sensibilidad de 97,8 % (IC 95 % = 97,3 - 98,2), especificidad 99,0 % (IC 95 % = 98,9 - 99,2), cociente de probabilidad positivo 75,4 (IC 95 % = 27,2 - 209,2) y negativo de 0,02 (IC 95 % = 0,01 - 0,07) y área bajo la curva de 99,8 %. Se concluye que la detección de anticuerpos presenta excelente validez, desempeño y utilidad diagnóstica para la detección del VHC en donantes de sangre y población general.