High Frequency of False-Positive Hepatitis C Virus Enzyme-Linked Immunosorbent Assay in Rakai, Uganda
CID
High Frequency of False-Positive Hepatitis C Virus Enzyme-Linked Immunosorbent Assay in Rakai, Uganda
Caroline E. Mullis 2 3 4
Oliver Laeyendecker 1 2 3
Steven J. Reynolds 1 2 3
Ponsiano Ocama 0 2
Jeffrey Quinn 2 3
Iga Boaz 2 7
Ronald H. Gray 2 6
Gregory D. Kirk 2 6
David L. Thomas 2 3
Thomas C. Quinn 1 2 3
Lara Stabinski 1 2 5
0 Department of Medicine, Makerere University , Kampala
1 Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health , Bethesda, Maryland
2 Received 27 June 2013; accepted 10 September 2013; electronically published 18 Septem- ber 2013
3 Department of Medicine, School of Medicine, Johns Hopkins University , Baltimore
4 Present affiliation: New York Medical College , Valhalla , New York
5 Present affiliation: Office of the Global AIDS Coordinator, US State Department , Washington, District of Columbia. 538A, Baltimore, MD
6 Department of Epidemiology, Bloomberg School of Public Health, Johns Hopkins University , Baltimore, Maryland
7 Rakai Health Sciences Program , Entebbe , Uganda
The prevalence of hepatitis C virus (HCV) infection in subSaharan Africa remains unclear. We tested 1000 individuals from Rakai, Uganda, with the Ortho version 3.0 HCV enzyme-linked immunosorbent assay. All serologically positive samples were tested for HCV RNA. Seventy-six of the 1000 (7.6%) participants were HCV antibody positive; none were confirmed by detection of HCV RNA.
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hepatitis C virus; ELISA; Africa.
Chronic hepatitis C virus (HCV) infection is a leading cause of
hepatocellular carcinoma and cirrhosis [1, 2]. Estimates of the
burden of HCV infection in sub-Saharan Africa vary widely,
but the overall seroprevalence is estimated at 3.0%, compared
to <1%2% in developed countries [2]. Understanding the
burden of HCV in sub-Saharan Africa is of particular
importance because of the high human immunodeficiency virus
(HIV) prevalence and the increased rate of complications
arising from HIV and HCV coinfection [1, 3]. As more
HIVinfected individuals in sub-Saharan Africa gain access to highly
active antiretroviral therapy (HAART) with resulting declines
in AIDS-related complications, liver disease associated with
hepatitis B virus (HBV) and HCV could become an
increasingly important cause of morbidity and mortality [4]. Additionally,
knowledge of HCV seroprevalence is critical for screening the
blood supply [3, 5].
In sub-Saharan Africa, HCV prevalence has primarily been
estimated by HCV antibody screening, without confirmatory
virologic testing because of the high cost associated with the
latter tests [1, 3, 4]. In Uganda, HCV seroprevalence estimates
range from 0.0% to 14.6% [1], but the observed variation may
reflect the performance of HCV antibody tests in this setting
[5]. Despite high sensitivity and specificity in US populations
[6], HCV antibody tests have been shown to have high
falsepositive misclassification in African populations, suggesting
that the reported seroprevalence may be inflated [7, 8].
Infection with malaria, syphilis, or HIV, malnutrition, and various
chronic diseases have been hypothesized to increase the false
positivity of HCV antibody tests, although these associations
remain speculative [7].
MATERIALS AND METHODS
We report analyses conducted on 500 HIV-infected individuals
enrolled in HIV care with the Rakai Health Sciences Program
frequency-matched by age, sex, and community to 500
HIV-uninfected participants of the Rakai Community Cohort Study [9].
Data collection included a structured interview focusing on
exposures potentially associated with liver disease, collection of
blood specimens, and a transient elastography (Fibroscan,
Echosense, Paris, France) examination to noninvasively quantify liver
fibrosis [9]. Methods for determining HIV type 1 (HIV-1) status
and CD4 nadir were previously described [9]. Presence of HBV
surface antigen and antibodies to schistosomiasis were
determined using an ETI-EKB s Plus enzyme-linked immunosorbent
assay (ELISA; Diasorin, Vercelli, Italy) and Schisto-96 soluble
egg antigen ELISA (IVD Research Inc, Carlsbad, California),
respectively [9]. All participants provided informed consent.
Institutional review board approval for this study was received from
the National Institute of Allergy and Infectious Diseases, the
Johns Hopkins Medical Institutions, the Western Institutional
Review Board (Olympia, Washington), the Scientific and Ethics
Committee of the Uganda Virus Research Institute, and the
Uganda National Council for Science and Technology.
Serum samples were tested manually using the Ortho HCV
version 3.0 ELISA Test System (Ortho Clinical Diagnostics,
Raritan, New Jersey). All samples were tested in a single well,
with initially reactive samples being retested in duplicate before
final interpretation. Any sample upon retesting that was
reactive for HCV antibody in either or both wells was then
considered repeatedly reactive and classified as HCV ELISA positive
for (...truncated)