TTV and HPV co-infection in cervical smears of patients with cervical lesions

OBJECTIVE To investigate the prevalence of transfusion-transmitted virus (TTV) and human papillomavirus (HPV) co-infection in cervical smears of patients with cervical lesions in littoral of Zhejiang province and analysis of transmitted route. METHODS Nested polymerase chain reaction (nPCR) was established. TTV DNA were tested by nPCR in cervical smears of 95 patients with cervical lesions and 55 healthy women, paired serum samples were available from 55 and 42 women, and their viral titer. The genotypes of 95 specimens of cervical cytology were detected with HybriMax. The phylogenetic group of TTV was determined by means of nPCR with N22 primers. RESULTS The prevalence of TTV DNA in cervical smears of patients with cervical lesions and healthy women was 52.7% (29/55) and was comparable with that in paired serum sample (50%). Symptomatic women had significantly higher prevalence of TTV DNA in cervical smears (74.7%) than healthy controls (P = 0.005). The TTV DNA prevalence in patient serum samples was 51%. The phylogenetic groups of TTV serum isolates were concordant with those of TTV from cervical smears of the same subjects, and genotype was G1b. The TTV viral titer in cervical smears were 10 to 1000 times as high as in serum. The total infection rate of HPV was 98.9% in patients, and was 27.3% in healthy women. The frequently detected genotype was HPV16, 18, 33 of HSIL, and HPV6 of LSIL. The HPV positive study subjects had significantly higher TTV DNA prevalence than HPV negatives (P = 0.02). CONCLUSION High prevalence of TTV in cervical smears suggests that sexual transmission is another mode of expansion of TTV infection among the population. The higher viral titer in cervical smears than in the respective serum samples might indicate active TTV replication in the female genital tract. Nevertheless, cooperation between TTV and HPV needs to be further investigated.