We investigated the performance of dried blood spots (DBS) in hepatitis C virus (HCV) diagnosis using modified commercial tests. Paired DBS and serum samples were collected from 200 patients: 100 patients with anti-HCV antibodies (anti-HCV), including 62 patients with detectable serum HCV RNA, and 100 patients without anti-HCV. The DBS sample consisted of three drops of approximately 50 L of whole blood applied to a paper card, which was then stored at ؊20°C within 48 hours of collection. Using the Ortho HCV 3.0 enzyme-linked immunosorbent assay kit on DBS, we observed both a specificity and sensitivity of 99% in detecting anti-HCV. HCV RNA was detected on DBS in 60/62 (97%) patients with detectable serum HCV RNA, which was then successfully quantified in 55 samples (89%) using the Cobas TaqMan HCV test. A good correlation was observed between the DBS HCV RNA concentration and the serum level (r 2 ‫؍‬ 0.95; P < 0.001). HCV genotyping was successfully performed on DBS samples, with a full concordance between the 14 paired DBS and serum samples (genotypes 1-4). Conclusion: This study presents DBS as a reliable alternative to serum specimens for detecting anti-HCV, quantifying HCV RNA and genotyping HCV. DBS may increase the opportunities for HCV testing and treatment follow-up in hard-to-reach individuals. (HEPATOLOGY 2010;51:752-758.) H epatitis C virus (HCV) infection is currently underdiagnosed, leaving many individuals unaware of their infection status. Some population groups, such as sex workers, the homeless, prisoners, or other institutionalized individuals, have a higher prevalence of HCV infection than the general population. [1][2][3] However, HCV testing in these groups is limited by the poor acceptability or feasibility of venipuncture. Collecting capillary blood spots on filter paper requires less staff training, is less invasive, involves smaller blood volumes, and is ideal for high-risk patients with damaged veins, such as intravenous drug users. 4 In addition, this technique can reduce the cost of HCV testing by simplifying sample collection, processing (no centrifugation), storage, and shipment. Many studies have already demonstrated the value of dried blood spots (DBS) for the serological and molecular diagnosis of human immunodeficiency virus. [5][6][7][8][9][10][11] Routine screening for HCV infection relies on detecting antibodies against HCV (anti-HCV) using highly sensitive second-or third-generation enzyme immunoassay. DBS have been used to detect anti-HCV among intravenous drug users, prisoners and childbearing women. 12-17 However, the diagnosis of acute or chronic infection also requires the detection of HCV RNA by polymerase chain reaction (PCR). 18,19 Likewise, when recent HCV infection is suspected or the patient is immunocompromised, then the sample should be referred for PCR. Samples with a low screening signal-to-cutoff ratio may also need confirmation with these more specific recombinant immunoblot assays. 20,21 In this study, we have investigated both anti-HCV and HCV RNA detecti...

People screened for human immunodeficiency virus (HIV) using rapid diagnostic tests (RDTs) in Africa remain generally unaware of their status for hepatitis B (HBV) and hepatitis C (HCV) infections. We evaluated a two-step screening strategy in Burkina Faso, using both HIV RDTs and Dried Blood Spot (DBS) assays to confirm an HIV-positive test, and to test for HBV and HCV infections. HIV counselling and point-of-care testing were performed at a voluntary counselling and testing centre with HBV, HCV status and HIV confirmation using DBS specimens, being assessed at a central laboratory. Serological testing on plasma was used as the reference standard assay to control for the performance of DBS assays. Nineteen out of 218 participants included in the study were positive for HIV using RDTs. A fourth-generation HIV ELISA and immunoblot assays on DBS confirmed HIV status. Twenty-four out of 25 participants infected with HBV were found positive for hepatitis B surface antigen (HBsAg) using DBS. One sample with a low HBsAg concentration on plasma was not detected on DBS. Five participants tested positive for HCV antibodies were confirmed positive with an immunoblot assay using DBS specimens. Laboratory results were communicated within 7 days to participants with no loss to follow up of participants between the first and second post-test counselling sessions. In conclusion, DBS collection during HIV point-of-care testing enables screening and confirmation of HBV, HCV and HIV infections. Diagnosis using DBS may assist with implementation of national programmes for HBV, HCV and HIV screening and clinical care in middle- to low-income countries.

This study supports both WHO recommendations of screening for HBV before initiation of ART and of using ART containing tenofovir and either lamivudine or emtricitabine in HIV-HBV-coinfected patients in Africa.

BackgroundThe decline in hepatitis B virus surface antigen (HBsAg) may be an early predictor of the viral efficacy of Hepatitis B virus (HBV) therapy. The HBsAg levels obtained by different immunoassays now need comparing and the relationships between levels of HBsAg and HBV DNA alongside HBsAg and genotype must be evaluated.Methodology/Principal FindingsHBsAg levels were compared among 80 patients using the Abbott Architect assay, a commercial immunoassay approved for HBsAg detection and quantitation, and three other assays derived from immunoassays approved for HBsAg detection (manufactured by Diasorin, Bio-Rad and Roche). Good correlation was found between the Abbot vs. Diasorin, Bio-Rad and Roche assays with narrow 95% limits of agreement and small mean differences: −0.06 to 0.11, −0.09 log10 IU/mL; −0.57 to 0.64, −0.04 log10 IU/mL; −0.09 to 0.45, −0.27 log10 IU/mL, respectively. These agreements were not affected by genotypes A or D. HBsAg was weakly correlated with HBV DNA, whatever the HBsAg assay used: Abbott, ρ = 0.36 p = 0.001, Diasorin ρ = 0.34, p = 0.002; Bio-Rad ρ = 0.37, p<0.001; or Roche ρ = 0.41, p<0.001. This relationship between levels of HBsAg and HBV DNA seemed to depend on genotypes. Whereas HBsAg (Abbott assay) tended to correlate with HBV DNA for genotype A (ρ = 0.44, p = 0.02), no such correlation was significant for genotypes D (ρ = 0.29, p = 0.15).Conclusion/SignificanceThe quantitation of HBsAg in routine clinical samples is comparable between the reference assay and the adapted assays with acceptable accuracy limits, low levels of variability and minimum discrepancy. While HBsAg quantitation is not affected by HBV genotype, the observed association between levels of HBsAg and HBV DNA seems genotype dependent.