Dried blood spot for hepatitis C virus serology and molecular testing

Abstract

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...

A hepatitis C avidity test for determining recent and past infections in both plasma and dried blood spots

“…The samples came from clinics run by community addition services. Group 4 consisted of 65 DBS taken from known chronic patients (tested anti-HCV and HCV PCR positive for >1 year) and group 5 consisted of 68 DBS from resolved patients (tested anti-HCV and HCV PCR negative for an average of 6 years, range [1][2][3][4][5][6][7][8][9][10][11][12][13][14]. The patients chosen for each group had had previous HCV results from plasma samples on record at WoSSVC.…”

“…1 It can be difficult to obtain a conventional blood sample from people who inject drugs (PWID) and dried blood spot (DBS) testing is a noninvasive method that can be used for antibody and PCR testing. [2][3][4] In specialist drug service settings in Scotland, it has contributed greatly to the rise in the number of HCV diagnoses. 1 DBS testing has also been used successfully for surveillance purposes.…”

Current and future use of “dried blood spot” analyses in clinical chemistry

“…Periods of storage at room temperature vary according to the biological factor, from 1 week for proteins [5], to 1 year or more for nucleic acids [6]. As far as serology is concerned, the blotting papers are usually kept at -20°C upon receipt [7]. For long-term preservation (up to several years) the blotting papers are stored either at −20°C or -80°C [8,9].…”

“…In addition, this analyte remains stable for over 15 days on DBS [30]. DBS is also well adapted for the enzyme-linked immunosorbent assay (ELISA) detection of specific antibodies against Epstein-Barr virus [50], Rubella virus [74], dengue virus [75] or hepatitis C [7,59] and HIV virus [13].…”

Comparative research of effectiveness of cellulose and fiberglass porous membrane carriers for bio sampling in veterinary and food industry monitoring

“…This method is a good alternative to the classical ones due to relative noninvasiveness, easy realization, simple sample treatment and storage, very low volumes of biomaterials applications [2]. In medical practice this approach was lately effectively adapted for infectious disease diagnostics [3,4], including human immunodeficiency virus [5][6][7][8], hepatitis [9][10][11][12], and flaviviridae [13]. Moreover, this technique is suggested as the major one for creating biobanks of humans [14].…”