Laboratory diagnosis of human hepatitis viruses

Sexually acquired hepatitis

OBJECTIVES

To assess current knowledge of sexually transmitted viral hepatitis in relation to epidemiology, clinical presentation, management, and diagnosis with particular reference to resource-poor settings.

METHOD

A search of published literature identified through Medline from 1966 to October 2001, the Cochrane Library, and reference lists taken from each article obtained. Textword and MeSH searches for hepatitis A, B, C, D, E, G, delta, GB virus, GBV-C, and TT virus were linked to searches under the textword terms sex$, prevent$, and MeSH subheadings, microbiology, complications, drug therapy, therapy, diagnosis, epidemiology, transmission, and prevention and control.

CONCLUSIONS

In heterosexual relationships, hepatitis B is readily transmitted sexually and hepatitis C and D less so, with no evidence for sexual transmission of hepatitis A. Hepatitis types A-D are all transmissible sexually in male homosexual relationships under certain conditions. In resource-poor countries sexual transmission is generally only a significant route of transmission for hepatitis B.

Detection of Epstein-Barr virus-specific antibodies by an automated enzyme immunoassay. Performance evaluation and cost analysis

Detection of antibodies to specific antigens of Epstein-Barr virus (EBV) has been conventionally performed by an immunofluorescence assay (IFA). The procedure is labor intensive and expensive, and interpretation of results is subjective. We evaluated an automated enzyme immunoassay (EIA) (INC-STAR Corp., Stillwater, MN, USA) using 290 serum specimens submitted for the diagnosis of acute infection with EBV. Antibodies (IgG, IgM) to EBV capsid antigen and IgG class antibodies to the nuclear antigen of the virus were obtained using the LABOTECH Automated Microplate Analyzer (BioChem ImmunoSystems Inc., Allentown, PA, USA) and were compared to the antibody profile results obtained by IFA and Western blot as the "gold standard." For detection of acute infection with EBV (presence of IgM and IgG antibodies to the capsid antigen; absence of antibodies to the nuclear antigen), the EIA had 100% sensitivity (11 of 11) and 99% specificity (275 of 279) compared to IFA and Western blot results. A cost analysis of IFA and EIA procedures, based on an estimated annual volume of 12,000 procedures, indicated that $236,000 direct cost and 1,400 h technologist time could be saved with the automated compared with immunofluorescence procedure. The automated EIA for determination of antibodies provides cost-effective, accurate diagnosis of EBV infections in laboratories processing high numbers of specimens now processed by IFA.