Prevalence of human papillomavirus infection in abnormal pap smears

This study was undertaken to study the prevalence of human papillomavirus (HPV) infection using the polymerase chain reaction (PCR) technique in abnormal cervical pap smears and to correlate the different cytological results with HPV infection.

A total of 1788 cervical pap smears of women more than 30 years of age conducted over a period of 1 year 3 months (June 2015-August 2016) were screened by liquid-based cytology. High-risk (HR)-HPV testing was performed by PCR in abnormal lesions. Inflammatory smears and some atypical squamous cells of undetermined significance (ASCUS)-reactive cases were excluded from HPV testing. Histopathological correlation was done wherever possible.

The overall prevalence of the intraepithelial lesions/malignancy was ASCUS. (ASCUS) - 79 (4.42%), atypical squamous cells cannot exclude high-grade squamous intraepithelial lesion (ASC-H) - 10 (0.56%), low-grade squamous intraepithelial lesion (LSIL) - 26 (1.45%), high-grade squamous intraepithelial lesion (HSIL) - 15 (0.84%), squamous cell carcinoma - 5 (0.28%), and adenocarcinoma - 1 case (0.06%). Overall, 136 (7.60%) samples were classified as abnormal. Seventy-seven samples were included for HR-HPV testing - 20 ASCUS, 10 ASC-H, 26 LSIL, 15 HSIL, and 6 malignant cases. A control group of ten samples with normal cervical cytology within the normal limit (Control) (WNLc) was tested for HR-HPV. HR-HPV was detected in 20% of samples of the WNLc group, 45% of the ASCUS group, 70% of the ASC-H group, 73.07% of the LSIL group, 86.67% of the HSIL, and 83.34% of the samples in the malignant group. Overall, HR-HPV was detected in 68.83% of abnormal cervical pap smears.

Our study shows that the percentage of HR-HPV-positive case increases with the severity of cytologic morphology. HPV had 4 times higher positivity in squamous intraepithelial lesion as compared to ASCUS.