Diagnosis of acute hepatitis C: anti-HCV or HCV-RNA?

Hepatitis C virus RNA assays: current and emerging technologies and their clinical applications

Molecular diagnostic assays represent a cornerstone in the management of hepatitis C virus (HCV) patients. Qualitative and quantitative HCV molecular assays are used for the diagnosis of acute and chronic HCV infections, viral genotyping, viral-load determination, treatment monitoring and prognosis. Reverse-transcription PCR, transcription-mediated amplification and branched DNA amplification are commonly employed for detection of HCV RNA. Recently, new HCV molecular assays that employ nanostructures have emerged and have been proposed as suitable for both low- and high-resource settings, without sacrificing sensitivity and specificity. This article will present current and future HCV molecular diagnostic assays with a focus on their clinical applications.

Low accuracy of the national reporting system of acute hepatitis C infection in Taiwan, 1995-2004

BACKGROUND AND AIM

This study attempted to clarify accuracy of acute hepatitis C (AHC) and its clinical characteristics.

METHODS

We reviewed 632 reported cases from national surveillance data of the Taiwan Center for Disease Control between 1995 and 2004, and reclassified diagnoses. A definite case was defined as alanine aminotransferase (ALT) > 10 x the upper limit of normal (ULN) with seroconversion of anti-hepatitis C virus antibody (anti-HCV). A probable case was defined as (i) seroconversion of anti-HCV and/or elevated ALT levels; or (ii) anti-HCV(+) but titers increased (from < 40 S/CO to >or= 40 S/CO) and ALT > 10 x the ULN. A suspected case was defined as initial anti-HCV(+) and ALT level > 10 x the ULN and/or jaundice. Excluded cases were defined as ALT levels less than 10 x ULN with initial positive anti-HCV Ab.

RESULTS

A total of 310 (49%) cases were confirmed as AHC; these included 95 (15%) definite and 215 (34%) probable cases. Higher incidence rates and accuracy of AHC were demonstrated in the southern area significantly if compared with northern, eastern and central areas, respectively (all P < 0.05). On comparison between blood centers and hospitals, more AHC cases were found in Southern Taiwan than in other areas (157/73 vs 24/40, P < 0.001), younger mean age (33.3 +/- 11.1 vs 49.3 +/- 16.4, P < 0.001), lower ALT levels (263.1 +/- 200.9 vs 1264.2 +/- 706.8, P < 0.001) and male predominance (191/39 vs 46/18, P = 0.046).

CONCLUSIONS

This study showed our reporting system over-estimated the AHC diagnosis, which is also a common issue worldwide. Greater efforts are needed to establish appropriate reporting systems, as well as more supplemental methods to distinguish between prevalent and incident cases.

Diagnosis of acute hepatitis C virus infection and estimated incidence in low- and high-risk English populations

The diagnosis of acute hepatitis C virus (HCV) infection is not straightforward; few people exhibit clinical symptoms and genome/antigen detection techniques do not indicate when infection had occurred. Here, a strategy to detect HCV RNA in the absence of antibody ('window-period') for diagnosis of acute infection is assessed. The sentinel surveillance of hepatitis testing study was used to retrospectively identify anti-HCV negative samples from high-risk individuals (2002-2003), for testing singly for HCV RNA. Additional samples were identified prospectively (2005) and tested in pools for HCV RNA. Positive samples were genotyped. Incidence and costs of adopting the pooling strategy were estimated. In the retrospective study, 8/390 (2.1%) samples were confirmed HCV RNA positive, anti-HCV negative. Prospectively, 3237 samples were tested in 325 pools. Five positive pools identified four confirmed HCV RNA positive patients (one false positive). Estimated incidence was 12.9 per 100 person-years in injecting drug users (IDUs) (retrospective study) and 3.7 per 100 person-years among drug/alcohol services and prison attendees (prospective study). Estimated costs were pound 850 per positive sample, in areas of higher risk. The yield from a window-period strategy depends upon the population tested. Pooled HCV RNA testing of anti-HCV negative samples from the current IDUs is realistic and relatively inexpensive to identify recently infected individuals.