Successful application of indirect in-situ polymerase chain reaction to tissues fixed in Bouin's solution

To evaluate the value of polymerase chain reaction-in situ hybridization (PCR-ISH) for the detection of human papillomaviruses (HPV) in paraffin sections of cervical biopsies fixed either in 10% formalin or in Bouin's solution.

We analysed 40 biopsies from Italian women infected with the human immunodeficiency virus type 1 (HIV 1). In-situ hybridization techniques were performed with commercial biotinylated probes. The PCR-ISH was carried out by the 'hot start modification'. Cervical intraepithelial neoplasia (CIN) was found in 23 of 40 patients (57. 5%); eight cases showed condylomatous features. Human papillomavirus was detected in 42.5% by ISH and in 65% by PCR-ISH. Sixty-nine per cent of positive biopsies contained HPV 16, 18, 31 and 33. HPV 6 and 11 were found only in condylomata acuminata samples.

The results point to a high incidence of HPV infection as well as of CIN in HIV-positive patients. Human papillomavirus type 16 appears to be most frequently associated with CIN. Polymerase chain reaction-ISH is more sensitive than ISH in the detection and typing of HPV DNA both in clinical and in 'latent' infections. The two techniques yielded the same results with either formalin- or Bouin's-fixed material.