Source
DDL Diagnostic Laboratory, Visseringlaan 25, Rijswijk, The Netherlands.
Abstract
HPV epidemiological and vaccine studies require highly sensitive HPV detection and genotyping systems. To improve HPV detection by PCR, the broad-spectrum L1 based SPF(10) PCR DEIA LiPA system and a novel E6 based multiplex type-specific system (MPTS123) using Luminex xMAP technology were combined into a new testing algorithm. To evaluate this algorithm, cervical swabs (n=860) and cervical biopsies (n=355) were tested with a focus on HPV detected by the MPTS123 assay (HPV-16, -18, -31, -33, -35, -39, -45, -51, -52, -56, -58, -59, -66, -68, -6 and -11). Among the HPV positive samples, identification of individual HPV genotypes was compared. When all MPTS123 targeted genotypes were taken together a good overall agreement was found (κ = 0.801, 95% CI: 0.784-0.818) with identification by SPF(10) LiPA, but significantly more genotypes (P<0.0001) were identified by the MPTS123 PCR Luminex assay, especially for HPV-16, -35, -39, -45, -58, and -59. An alternative type-specific assay was evaluated, based on detection of a limited number of HPV genotypes by type-specific PCR and a reverse hybridization assay (MPTS12 RHA). This assay showed similar results as the expanded MPTS123 Luminex assay.These results confirm the fact that broad-spectrum PCRs are hampered by type competition when multiple HPV genotypes are present in the same sample. Therefore, a testing algorithm combining the broad-spectrum PCR and a range of type-specific PCRs offers a highly accurate method for the analysis of HPV infections and diminishes the rate of false-negative results, which may be particularly useful for epidemiological and vaccine studies.