The aim of this work was to examine different methods of investigation in the diagnosis of the abnormal "low grade" transformation zone of the portio. Over a period of one year 41 patients subjected to colposcopic examination underwent exo-endocervical sampling for oncologic evaluation and for detection of viral and bacterial infections (HPV, HSV. adenovirus, mycoplasmas and chlamydia trachomatis), as well as portio biopsy. A 65.8% correlation was found between cytology and the HPV-DNA test results. while histology and the presence of the HPV virus agreed in 51.4% of cases. In those cases in which minimal histological alterations were found (koilocytosis) a high percentage of HPV negativity was found. In discordant negative cytologic tests that were however positive for HPV by PCR. the genotypes identified were always 6 and 11.