Anal cytology has been used for screening the anal carcinoma and its precursors in risk populations. When anal canal smear shows cytological alterations, examination with colposcope and acetic acid is indicated to identify and perform biopsy to confirm the finding. Few studies show the follow-up of patients treated with anal HPV induced lesions. We are using both methods in association and subclinical lesions have been found in 50% of patients, whose proctological examinations are free from HPV lesions. However, some smears have cytological alterations, despite anal colposcopy being normal. The aim of this study was to observe these lesions' behavior in a six-month follow-up, during a year, and to assess whether this periodicity of re-evaluations was enough to avoid high grade or superior lesions. We have found 58 (21%) among 273 patients with these parameters. One year re-evaluations of 22 of the patients showed that anal colposcopies remained normal in 17 (74%). In five (22%), the cytology returned to normality and in 12 (52%), the same abnormality was seen. The other six patients (26%) developed clinical or subclinical HPV induced lesions. T CD4+ lymphocytes counts of HIV-positive patients were inferior in those whose lesions progressed. These results permitted us to conclude that cytological alterations can progress or clear in these patients, and they have close relationship with the immunity, and the six-month interval is enough to each re-evaluation.
