Detection of Human Papillomavirus (HPV) DNA in Cervical Swabs by the Polymerase Chain Reaction

Abstract

The polymerase chain reaction (PCR) was used to detect human papillomavirus (HPV) type 16 DNA in cervical swabs from 37 patients with HPV 16-harboring cervical lesions (15 carcinomas and 22 cervical intraepithelial neoplasias). Primers amplifying a sequence of the human beta-globin genome were used for internal control together with the HPV 16-specific primers. The cell samples were prepared for PCR analysis by two different methods: either by phenol/chloroform extraction or by boiling in the presence of a chelating agent. HPV 16 DNA was found in 27 swabs. The detection rates were identical with both methods of preparation. Four of the 10 false-negative swabs contained too little DNA to permit amplification with the genomic primers. Excluding these insufficient samples, the detection rate was 82%. Reasons for false-negative results may include low cell numbers or failure to obtain cells representative of the underlying lesion. In conclusion, the PCR offers a satisfactory method of HPV detection in cervical swabs. Cell preparation can be restricted to simple boiling with a chelating agent. For optimal results, samples containing less than 2 x 10(4) cells should be discarded, and genomic primers should be used for internal control.