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Establishing a sample-to cut-off ratio for lab-diagnosis of hepatitis C virus in Indian context.

Tiwari AK, Pandey PK, Negi A, Bagga R, Shanker A, Baveja U, Vimarsh R, Bhargava R, Dara RC, Rawat G - Asian J Transfus Sci (2015 Jul-Dec)

Bottom Line: Center for Disease Control reported that signal-to-cut-off (s/co) ratios in anti-HCV antibody tests like EIA/CIA can be used to predict the probable result of supplemental test; above a certain s/co value it is most likely to be true-HCV positive result and below that certain s/co it is most likely to be false-positive result.PCR test results were used to define true negatives, false negatives, true positives, and false positives.An s/co ratio of ≥6 worked out to be over 95% sensitive and almost 92% specific in 438 consecutive patient samples tested.

View Article: PubMed Central - PubMed

Affiliation: Department of Transfusion Medicine, Medanta-The Medicity, Gurgaon, Haryana, India.

ABSTRACT

Introduction: Lab-diagnosis of hepatitis C virus (HCV) is based on detecting specific antibodies by enzyme immuno-assay (EIA) or chemiluminescence immuno-assay (CIA). Center for Disease Control reported that signal-to-cut-off (s/co) ratios in anti-HCV antibody tests like EIA/CIA can be used to predict the probable result of supplemental test; above a certain s/co value it is most likely to be true-HCV positive result and below that certain s/co it is most likely to be false-positive result. A prospective study was undertaken in patients in tertiary care setting for establishing this "certain" s/co value.

Materials and methods: The study was carried out in consecutive patients requiring HCV testing for screening/diagnosis and medical management. These samples were tested for anti-HCV on CIA (VITROS(®) Anti-HCV assay, Ortho-Clinical Diagnostics, New Jersey) for calculating s/co value. The supplemental nucleic acid test used was polymerase chain reaction (PCR) (Abbott). PCR test results were used to define true negatives, false negatives, true positives, and false positives. Performance of different putative s/co ratios versus PCR was measured using sensitivity, specificity, positive predictive value and negative predictive value and most appropriate s/co was considered on basis of highest specificity at sensitivity of at least 95%.

Results: An s/co ratio of ≥6 worked out to be over 95% sensitive and almost 92% specific in 438 consecutive patient samples tested.

Conclusion: The s/co ratio of six can be used for lab-diagnosis of HCV infection; those with s/co higher than six can be diagnosed to have HCV infection without any need for supplemental assays.

No MeSH data available.


Related in: MedlinePlus

The receiver operator characteristics curve for signal-to-cut-off ratio of six (6)
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Figure 1: The receiver operator characteristics curve for signal-to-cut-off ratio of six (6)

Mentions: The diagnostic accuracy of this s/co ratio of six was also confirmed by plotting a ROC. The AUC of the ROC curve was 0.985 (95% confidence interval: 0.971-1.000) (Figure 1).


Establishing a sample-to cut-off ratio for lab-diagnosis of hepatitis C virus in Indian context.

Tiwari AK, Pandey PK, Negi A, Bagga R, Shanker A, Baveja U, Vimarsh R, Bhargava R, Dara RC, Rawat G - Asian J Transfus Sci (2015 Jul-Dec)

The receiver operator characteristics curve for signal-to-cut-off ratio of six (6)
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4562143&req=5

Figure 1: The receiver operator characteristics curve for signal-to-cut-off ratio of six (6)
Mentions: The diagnostic accuracy of this s/co ratio of six was also confirmed by plotting a ROC. The AUC of the ROC curve was 0.985 (95% confidence interval: 0.971-1.000) (Figure 1).

Bottom Line: Center for Disease Control reported that signal-to-cut-off (s/co) ratios in anti-HCV antibody tests like EIA/CIA can be used to predict the probable result of supplemental test; above a certain s/co value it is most likely to be true-HCV positive result and below that certain s/co it is most likely to be false-positive result.PCR test results were used to define true negatives, false negatives, true positives, and false positives.An s/co ratio of ≥6 worked out to be over 95% sensitive and almost 92% specific in 438 consecutive patient samples tested.

View Article: PubMed Central - PubMed

Affiliation: Department of Transfusion Medicine, Medanta-The Medicity, Gurgaon, Haryana, India.

ABSTRACT

Introduction: Lab-diagnosis of hepatitis C virus (HCV) is based on detecting specific antibodies by enzyme immuno-assay (EIA) or chemiluminescence immuno-assay (CIA). Center for Disease Control reported that signal-to-cut-off (s/co) ratios in anti-HCV antibody tests like EIA/CIA can be used to predict the probable result of supplemental test; above a certain s/co value it is most likely to be true-HCV positive result and below that certain s/co it is most likely to be false-positive result. A prospective study was undertaken in patients in tertiary care setting for establishing this "certain" s/co value.

Materials and methods: The study was carried out in consecutive patients requiring HCV testing for screening/diagnosis and medical management. These samples were tested for anti-HCV on CIA (VITROS(®) Anti-HCV assay, Ortho-Clinical Diagnostics, New Jersey) for calculating s/co value. The supplemental nucleic acid test used was polymerase chain reaction (PCR) (Abbott). PCR test results were used to define true negatives, false negatives, true positives, and false positives. Performance of different putative s/co ratios versus PCR was measured using sensitivity, specificity, positive predictive value and negative predictive value and most appropriate s/co was considered on basis of highest specificity at sensitivity of at least 95%.

Results: An s/co ratio of ≥6 worked out to be over 95% sensitive and almost 92% specific in 438 consecutive patient samples tested.

Conclusion: The s/co ratio of six can be used for lab-diagnosis of HCV infection; those with s/co higher than six can be diagnosed to have HCV infection without any need for supplemental assays.

No MeSH data available.


Related in: MedlinePlus