Real-time Taqman PCR targeting 14 human papilloma virus types

Subtyping of human papilloma virus (HPV) may enhance the precision of vaginal cytological assessments and will be important for investigating the effect of the recently introduced vaccine against types 16 and 18.To evaluate an in-house real-time PCR targeting HPV types 16-18-31-33-35-39-45-51-52-56-58-59-6-11, by analysing 107 liquid-based cytology specimens representing various degrees of dysplasia.In all, 71 samples were HPV positive, with multiple types present in 37 (52%). Comparison with Roche Linear Array on a subset of 24 of these 71 samples showed a good agreement. One or several types were detected in 17/17 (100%) samples with cervical intraepithelial neoplasia grade 2-3 (CIN 2-3), 16/19 (84%) with CIN 1, 32/43 (74%) with Atypical Squamous Cells of Undetermined Significance (ASCUS), and in 6/28 (21%) with benign cytology. Estimates of mean viral load were lower in CIN 1-3 than in ASCUS ( approximately 4000 vs. approximately 25,000 copies/1000 cells), and clearly lower in samples with benign cytology ( approximately 50 copies/1000 cells).The HPV rates in groups with different degrees of dysplasia agrees with previous reports and support a strong link between types 16/18 and severe dysplasia. The high rate of multiple type infection might influence the outcome of HPV vaccination. The possible importance of viral load should be further studied.