Human papillomavirus types in cervical biopsy specimens from Pap-smear-negative women with external genital warts

Number of external anogenital warts is associated with the occurrence of abnormal cervical cytology

BACKGROUND

Anogenital warts (AGWs) are common results of sexually transmitted infection (STI). Human papillomavirus (HPV) types 6 and 11, which are non-oncogenic types, account for 90% of the clinical manifestations. Although the quadrivalent HPV vaccine has been launched, AGW remains prevalent in some countries and shows association with abnormal cervical cytology.

OBJECTIVES

To study the prevalence of abnormal cervical cytology (low grade squamous intraepithelial lesions or worse; LSIL+) in immunocompetent Thai women newly presenting with external AGWs.

MATERIALS AND METHODS

Medical charts of all women attending Siriraj STI clinic during 2007-2011 were reviewed. Only women presenting with external AGWs who were not immunocompromised (pregnant, human immunodeficiency virus positive or being on immunosuppressant drugs) and had not been diagnosed with cervical cancer were included into the study. Multivariate analysis was used to determine the association between the characteristics of the patients and those of AGWs and LSIL+.

RESULTS

A total of 191 women were eligible, with a mean age of 27.0±8.9 years; and a mean body mass index of 20.6±8.9 kg/m2. Half of them finished university. The most common type of AGWs was exophytic (80.1%). The posterior fourchette appeared to be the most common affected site of the warts (31.9%), followed by labia minora (26.6%) and mons pubis (19.9%). The median number of lesions was 3 (range 1-20). Around 40% of them had recurrent warts within 6 months after completing the treatment. The prevalence of LSIL+ at the first visit was 16.3% (LSIL 12.6%, ASC-H 1.1%, HSIL 2.6%). After adjusting for age, parity and miscarriage, number of warts ≥ 5 was the only factor associated with LSIL+ (aOR 2.65, 95%CI 1.11-6.29, p 0.027).

CONCLUSIONS

LSIL+ is prevalent among immunocompetent Thai women presenting with external AGWs, especially those with multiple lesions.

Serological responses to human papillomavirus type 6 and 16 virus-like particles in patients with cervical neoplastic lesions

Serum samples from 36 cervical carcinoma patients, 33 patients with high-grade squamous intraepithelial lesions, and 31 cytologically normal women were tested by enzyme-linked immunosorbent assay (ELISA) using human papilloma virus type 6 (HPV 6) and HPV 16 virus-like particles as antigens. Forty serum specimens from 1-year-old children were used to assign cutoff points. When serum samples from the subjects infected with HPV 16 were tested in an HPV 16 ELISA detecting immunoglobulin A (IgA), IgG, and IgM binding, 61% showed IgA, 44% showed IgG, and 39% showed IgM reactivity. Of HPV 6- or 11- or HPV 18-infected subjects. fewer than 17% showed IgA or IgG responses and 33% showed IgM reactivity. In contrast, 13% showed IgA, 10% showed IgG, and 16% showed IgM reactivity in the HPV DNA-negative controls. The results suggest that the IgA and IgG responses are HPV 16 specific and the IgM response is cross-reactive to different HPV types. On the other hand, the serological responses to HPV 6 did not differ in the patient and control groups. The percentages of patients positive for both IgA and IgG antibodies were significantly higher in the groups with high-grade squamous intraepithelial lesions (12% [4 of 33]; P = 0.04) and cancer (17% [6 of 36]; P = 0.02) than in the healty women (0% [0 of 31]), and the percentages for either IgA or IgG were higher for the cancer group (47% [17 of 36]; P = 0.01) than in the normal group (19% [6 of 31]). Most sera positive for IgA and IgG in the patient groups showed higher titers than those in the normal group. All these results suggest that high IgA and IgG responses are good indicators for estimating HPV 16 infection.

Detection of human papillomavirus DNA by in situ hybridization and polymerase chain reaction in human papillomavirus equivocal and dysplastic cervical biopsies

One hundred twenty-one paraffin-embedded cervical biopsy specimens were tested for the presence of human papillomavirus (HPV) DNA by in situ hybridization and polymerase chain reaction. By in situ hybridization using probes for HPV types 6/11, 16/18, 31/33/35, 42/43/44, 51/52, and 45/56, HPV DNA was found in none of 20 normal/squamous metaplasia biopsy specimens, in one of 76 HPV equivocal biopsy specimens, in seven of 12 condyloma/mild dysplasia biopsy specimens, and in 12 of 13 moderate/severe dysplasia biopsy specimens. Polymerase chain reaction using HPV L1 consensus sequence primers followed by filter hybridization of the amplification products was positive for HPV DNA in two of 20 normal/squamous metaplasia biopsy specimens, in 23 of 76 HPV equivocal biopsy specimens, in eight of 12 condyloma/mild dysplasia biopsy specimens, and in 12 of 13 moderate/severe dysplasia biopsy specimens. Among biopsies that tested positive by polymerase chain reaction but that were negative by in situ hybridization, the most commonly identified HPV was type 16. We conclude that although HPV equivocal biopsy specimens contain HPV DNA more frequently than histologically normal tissue, the majority of biopsy specimens in this category test negative for HPV DNA. The clinical significance of a positive test for HPV, in the absence of unequivocal histologic changes, remains to be determined.