Analysis of the Patients with Indeterminate Results by Anti-HIV Western Blot Assay: Experience of a University Hospital During Recent 5 Years in Korea / 임상검사와정도관리

ABSTRACT

BACKGROUND: Interpretation of indeterminate results by anti-HIV Western blot assay, which is currently used as a confirmatory test for HIV infection, can be usually difficult. We analyzed outcomes of the patients with indeterminate results by anti-HIV Western blot. METHODS: Medical records of patients, who were indeterminate by the anti-HIV Western blot assay in a university hospital during recent 5 years, were retrospectively reviewed. HIV screening test was performed by chemiluminescent immunoassay autoanalyzer (Abbot Laboratories, USA) with HIV Ag/Ab Combo kits. Confirmatory Western blot assay for the positive samples by HIV screening test was committed to the Korean National Institute of Health. RESULTS: A total of 202,639 specimens were tested for HIV screening during the period, and 644 (0.32%) sera showed positive results. Among these, 46 (7.1%) cases were indeterminate by the Western blot, which were from 20 patients, and 13 of them converted to be anti-HIV positive, and 3 were lost to follow-up. Another four patients were turned out to be negative for HIV infection, including two neonates from HIV-positive mothers receiving antiviral treatment during pregnancy. CONCLUSIONS: Most of the patients who showed Western blot-indeterminate results converted to HIV positive after follow-up. Thus, careful monitoring of patients with indeterminate Western blot results should be essential.