Skip to main page content

• HOME
• Current Issue
• Archive
• Alerts
• About ASM
• Contact us
• Tech Support
• Journals.ASM.org

This Article Abstract Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Quiroga, J. A. Articles by Carreño, V. Search for Related Content PubMed PubMed Citation Articles by Quiroga, J. A. Articles by Carreño, V.

 Previous Article  |  Next Article 

Journal of Clinical Microbiology, December 2006, p. 4559-4560, Vol. 44, No. 12
0095-1137/06/$08.00+0     doi:10.1128/JCM.01440-06
Copyright © 2006, American Society for Microbiology. All Rights Reserved.

Combined Hepatitis C Virus (HCV) Antigen-Antibody Detection Assay Does Not Improve Diagnosis for Seronegative Individuals with Occult HCV Infection

Juan A. Quiroga, Inmaculada Castillo, Margarita Pardo, Elena Rodríguez-Iñigo, and Vicente Carreño^*

Fundación para el Estudio de las Hepatitis Virales, Madrid, Spain

Received 12 July 2006/ Returned for modification 22 August 2006/ Accepted 26 September 2006

Top Abstract Text References

 
A combined hepatitis C virus (HCV) antigen-antibody assay was evaluated for 115 seronegative individuals with occult HCV infection. The assay was reactive in one patient and negative to weakly reactive in three others (all four gave indeterminate results by supplemental assay) but failed to detect HCV in the remaining patients. Despite increased sensitivity the combined assay does not improve serodiagnosis of occult HCV infection.

Top Abstract Text References

 
Occult hepatitis C virus (HCV) infection has been recently identified in patients with persistently abnormal results of unknown etiology in liver function tests (2, 3). This type of infection is evidenced only by the detection of HCV RNA in liver, because patients consistently test negative for antibodies to HCV and HCV RNA in serum. Diagnosis of occult HCV infection is possible only by liver biopsy, which is not routinely performed due to associated morbidity. Thus, the availability of an assay with increased sensitivity for HCV infection will greatly improve the diagnosis of occult HCV infection. A combined HCV antigen-antibody assay that simultaneously detects capsid antigen and specific HCV antibodies in serum has been developed (4). This combined assay has shown increased sensitivity compared with classical anti-HCV assays (1, 4). Our aim has been to assess whether the combined HCV antigen-antibody assay allows HCV serodiagnosis in patients with occult HCV infection.

Over the past 4 years 115 patients have been diagnosed with occult HCV infection according to published criteria (2): they were serum anti-HCV negative (Innotest-HCV Ab IV; Innogenetics, Gent, Belgium) and serum HCV RNA negative (sensitivity of 50 IU/ml; specificity of 99%; Amplicor HCV version 2.0; Roche Diagnostics, Branchburg, NJ) and presented sustained abnormal results of unknown etiology in liver function tests prior to undergoing a liver biopsy which demonstrated the presence of hepatic HCV RNA. Patients were monitored, and blood samples were collected at each visit. Serum samples were tested by use of Monolisa HCV Ag-Ab Ultra (Bio-Rad Laboratories, Marnes-la-Coquette, France) according to the supplier's instructions; sample-to-cutoff absorbance (SCO) ratios equal to or greater than 1 were considered reactive. HCV seroreactivity was confirmed by supplemental testing for anti-HCV antibodies by immunoblot assay (DeciScan HCV Plus; Bio-Rad).

The combined HCV antigen-antibody assay was evaluated using sera from 115 seronegative individuals with occult HCV infection. The assay was reactive (SCO > 1) in only one patient (0.9%). Use of a more sensitive SCO threshold of 0.5 (1, 4, 8) led to the identification of three more patients (3.5% positive overall). However, the remaining 111 patients had SCO ratios less than 0.3 and were scored negative by the combined assay. In the supplemental immunoblot assay, all four of the positive samples gave indeterminate results. Table 1 summarizes the characteristics of these four patients. In addition, as shown in Fig. 1, weak positivity continued to be detected by the combined assay in sequential samples from one reactive patient (patient no. 1 in Table 1), whereas in another patient (patient no. 3 in Table 1) HCV responses remained within the gray zone, with ratios of 0.5 to 1 during the follow-up. The explanation for these findings is not clear. The mechanisms that regulate humoral immune responses in HCV infection are not well known. Thus, HCV-specific antibody responses persist for decades in patients with chronic hepatitis C but gradually decrease and eventually disappear after recovery from HCV infection (10, 11). Patients with occult HCV are similar to those who have previously been considered to have recovered because they consistently test HCV RNA negative without detectable HCV-specific humoral responses (10).

View this table: [in this window] [in a new window]

TABLE 1. Characteristics of patients reactive by Monolisa HCV Ag-Ab Ultra assay

View larger version (8K): [in this window] [in a new window]

FIG. 1. Time course of SCO ratios of sequential serum samples tested by Monolisa HCV Ag-Ab Ultra assay in two patients with occult HCV infection. Squares, patient no. 1; circles, patient no. 3 (Table 1). Horizontal lines denote thresholds for detection set at SCO of 1 (upper line) and 0.5 (lower line).

The combined HCV antigen-antibody assay has allowed serodiagnosis in four patients with occult HCV infection who have repeatedly tested negative by commercial assays. However, the slight increase in sensitivity achieved using the combined assay does not improve the routine serological diagnosis of occult HCV infection. Despite the permanent lack of detectable anti-HCV antibodies using commercial enzyme-linked immunoassays, we have found that some of these samples from occult HCV-infected patients react with HCV proteins on immunoblot assays. Weak reactions can be observed in immunoblot testing in cases of negative screening reaction by enzyme-linked immunosorbent assay. Such profiles have been confirmed in follow-up samples from prison inmates (6) despite repeated nonreactive HCV results in enzyme-linked immunosorbent assays, likely reflecting a low level of specific antibodies indicating exposure to HCV (7, 9). In fact, we have observed that HCV responses remained weak in the follow-up samples of two patients with occult HCV infection (Fig. 1). Therefore, low to weakly reactive SCO ratios appear to indicate the presence of anti-HCV antibodies in serum at very low levels, as suggested previously (9). These findings emphasize that current serodiagnostic reagents are not sufficient for occult HCV diagnosis, and thus, liver biopsy remains the "gold standard" for reliable diagnosis of occult HCV infection.

The search for a less invasive test for occult HCV infection has important clinical implications because of the risks associated with liver biopsy. Thus, it may be important to introduce more sensitive serological assays to test for HCV exposure in at-risk populations, such as HCV-seronegative individuals with liver disease, hemodialysis patients (1, 4), or blood donors (5).

 
We are grateful to M. Escudero from Bio-Rad Laboratories for providing Monolisa HCV Ag-Ab Ultra reagents.

This work has been supported in part by a grant from Fundación de Investigaciones Biomédicas, Madrid, Spain.

 
* Corresponding author. Mailing address: Fundación para el Estudio de las Hepatitis Virales, Guzmán el Bueno 72, 28015 Madrid, Spain. Phone: 34-91.544.6013. Fax: 34-91.544.9228. E-mail: fehvhpa{at}fehv.org.

Published ahead of print on 4 October 2006.

Top Abstract Text References

 

1
1. Ansaldi, F., B. Bruzzone, G. Testino, M. Bassetti, R. Gasparini, P. Crovari, and G. Icardi. 2006. Combination hepatitis C virus antigen and antibody immunoassay as a new tool for early diagnosis of infection. J. Viral Hepat. 13:5-10.[CrossRef][Medline]
2
2. Castillo, I., M. Pardo, J. Bartolomé, N. Ortiz-Movilla, E. Rodríguez-Iñigo, S. de Lucas, C. Salas, J. A. Jiménez-Hefferman, A. Pérez-Mota, J. Graus, J. M. López-Alcorocho, and V. Carreño. 2004. Occult hepatitis C virus infection in patients in whom the etiology of persistently abnormal results of liver-function tests is unknown. J. Infect. Dis. 189:7-14.[Medline]
3
3. Castillo, I., E. Rodríguez-Iñigo, J. Bartolomé, S. de Lucas, N. Ortíz-Movilla, J. M. López-Alcorocho, M. Pardo, and V. Carreño. 2005. Hepatitis C virus replicates in peripheral blood mononuclear cells of patients with occult hepatitis C virus infection. Gut 54:682-685.[Abstract/Free Full Text]
4
4. Laperche, S., N. Le Marrec, A. Girault, F. Bouchardeau, A. Servant-Delmas, M. Maniez-Montreuil, P. Gallian, T. Levayer, P. Morel, and N. Simon. 2005. Simultaneous detection of hepatitis C virus (HCV) core antigen and anti-HCV antibodies improves the early detection of HCV infection. J. Clin. Microbiol. 43:3877-3883.[Abstract/Free Full Text]
5
5. Laperche, S., M. H. Elghouzzi, P. Morel, M. Asso-Bonnet, N. Le Marrec, A. Girault, A. Servant-Delmas, F. Bouchardeau, M. Deschaseaux, and Y. Piquet. 2005. Is an assay for simultaneous detection of hepatitis C virus core antigen and antibody a valuable alternative to nucleic acid testing? Transfusion 45:1965-1972.[CrossRef][Medline]
6
6. Post, J. J., Y. Pan, A. J. Freeman, C. E. Harvey, P. A. White, P. Palladinetti, P. S. Haber, G. Marinos, M. H. Levy, J. M. Kaldor, K. A. Dolan, R. A. French, A. R. Lloyd, W. D. Rawlinson, and Hepatitis C Incidence and Transmission in Prisons Study (HITS) Group. 2004. Clearance of hepatitis C viremia associated with cellular immunity in the absence of seroconversion in the hepatitis C incidence and transmission in prisons study cohort. J. Infect. Dis. 189:1846-1855.[CrossRef][Medline]
7
7. Quiroga, J. A., and V. Carreño. 2005. HCV-indeterminate blood donors or occult HCV infection? Lancet 365:1540-1541.[CrossRef][Medline]
8
8. Schnuriger, A., S. Dominguez, M. A. Valantin, R. Tubiana, C. Duvivier, J. Ghosn, A. Simon, C. Katlama, and V. Thibault. 2006. Early detection of hepatitis C virus infection by use of a new combined antigen-antibody detection assay: potential use for high-risk individuals. J. Clin. Microbiol. 44:1561-1563.[Abstract/Free Full Text]
9
9. Semmo, N., E. Barnes, C. Taylor, J. Kurtz, G. Harcourt, N. Smith, and P. Klenerman. 2005. T-cell responses and previous exposure to hepatitis virus in indeterminate blood donors. Lancet 365:327-329.[Medline]
10
10. Takaki, A., M. Wiese, G. Maertens, E. Depla, U. Seifert, A. Liebetrau, J. L. Miller, J. L., M. P. Manns, and B. Rehermann. 2000. Cellular immune responses persist and humoral responses decrease two decades after recovery from a single-source outbreak of hepatitis C. Nat. Med. 6:578-582.[CrossRef][Medline]
11
11. Toyoda, H., T. Kumada, S. Kiriyama, Y. Sone, M. Tanikawa, Y. Hisanaga, T. Kuzuya, T. Honda, K. Hayashi, I. Nakano, Y. Katano, and H. Goto. 2005. Changes in hepatitis C virus (HCV) antibody status in patients with chronic hepatitis C after eradication of HCV infection by interferon therapy. Clin. Infect. Dis. 15:49-54.[CrossRef]

---

Journal of Clinical Microbiology, December 2006, p. 4559-4560, Vol. 44, No. 12
0095-1137/06/$08.00+0     doi:10.1128/JCM.01440-06
Copyright © 2006, American Society for Microbiology. All Rights Reserved.

This article has been cited by other articles:

• Quiroga, J. A., Castillo, I., Bartolome, J., Carreno, V. (2007). Serum Immunoglobulin G Antibodies to the GOR Autoepitope Are Present in Patients with Occult Hepatitis C Virus (HCV) Infection despite Lack of HCV-Specific Antibodies. CVI 14: 1302-1306 [Abstract] [Full Text]  

This Article Abstract Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Quiroga, J. A. Articles by Carreño, V. Search for Related Content PubMed PubMed Citation Articles by Quiroga, J. A. Articles by Carreño, V.