DNA hybridisation of cervical scrapes: comparison with cytological findings in Papanicolaou smears

Human papillomavirus infection and therapy with interferon

The studies summarized have shown that therapy of condylomata acuminata with interferon is effective. The route of administration does not appear to influence the results; the intralesional, intramuscular, and subcutaneous routes were effective. Additional research is required to determine whether the natural interferon or recombinant product is superior. The appropriate administration schedule may also not have been attained.

A comparison between cytology and histology to detect anal intraepithelial neoplasia

INTRODUCTION

Anal intraepithelial neoplasia (AIN), which may be a precursor of anal carcinoma, has been identified on histology following minor anal surgical procedures, in particular the removal of perianal condylomata, in increasing numbers of homosexual and bisexual men. Anal cytology has recently been proposed as a useful method of identifying AIN lesions.

OBJECTIVE

To compare anal cytology with histology as a method of detecting AIN.

METHODS

215 homosexual and bisexual men attending a central London sexually transmitted diseases clinic had an anal cytological smear performed under standard conditions. The perianal area and anal canal were then examined using a colposcope, and areas macroscopically suggestive of intraepithelial neoplasia were biopsied.

RESULTS

176 of the 215 patients were biopsied of whom 76 had AIN on histology. 154 of the 215 patients had an adequate anal smear of whom 46 and 85 had cytological features of both HPV and AIN, or HPV alone respectively. Including features of HPV alone as an abnormal smear, anal cytology, when compared with anoscopy and histology as the gold standard for diagnosing AIN, resulted in a sensitivity of 87.5%, a specificity of 16.3%, a positive predictive value of 37.4% and a negative predictive value of 69.6%. Restricting abnormal smears to those with features of both HPV and AIN resulted in a sensitivity of 33.9%, a specificity of 72.5%, a positive predictive value of 41.3% and a negative predictive value of 65.7%.

CONCLUSION

Anal cytology is a sensitive but nonspecific method of identifying patients with biopsy proven AIN if cytological features of HPV alone are included as abnormal smears. Specificity is improved by restricting abnormal smears to those with features of both HPV and AIN but this markedly lowers the sensitivity of the test. At present, anoscopy and histology are required in addition to anal cytology to differentiate between patients who simply have anal condylomata and those who also have AIN.

Patients with various types of human papillomavirus: covariation and diagnostic relevance of cytological findings in Papanicolaou smears

Human papillomavirus (HPV) infection in the genital tract is associated with a number of cytological changes which are accepted as standard criteria for a cytological diagnosis. We evaluated the covariation and diagnostic accuracy of these criteria in 210 patients, i.e. 150 cases who were positive for HPV types 6, 11, 16, 18, 31, 33 or 35, and 60 cases who were HPV-negative by simultaneous Southern blot analysis. This was done by re-examining cervical smears obtained at the same time, without knowing the results of the Southern blot analysis, for the presence of koilocytosis, dyskeratosis-parakeratosis, nuclear smudging, hyperchromasia, binucleation, multinucleation, karyorrhexis and macrocytosis. We found that all these cytological changes correlated with the presence of an HPV infection. However, analysis of variance showed that koilocytosis, dyskeratosis-parakeratosis and karyorrhexis were of particular diagnostic value, while the other features provided little or no additional information. By omitting these features and making the diagnosis when two out of three of the key criteria, i.e. koilocytosis, dyskeratosis-parakeratosis and karyorrhexis were present, we diagnosed HPV infection with a specificity of 100% in 36% of the 150 cases, which were positive by Southern blot analysis. The various HPV types produced different morphological patterns which may reflect differences in action on the host cell. In the individual patient, however, such differences in cytology do not provide a sound basis for distinguishing between viral types.

Factors associated with clinical and sub-clinical anal human papillomavirus infection in homosexual men

OBJECTIVES

(I) to determine the relative sensitivities of clinical examination, cytology and HPV DNA hybridisation for the detection of anal human papillomavirus infection; and (ii) to examine various factors which may influence presentation of anal human papillomavirus infection in homosexual men.

METHODS AND RESULTS

112 unselected homosexual men attending a Sydney STD clinic for routine screening underwent a complete anogenital and physical examination, during which blood samples (for haematological, serological and immunological investigations), rectal swabs (for culture of anal pathogens) and anal scrapes of the dentate line (for cytology and HPV DNA hybridisation) were collected. Papanicolaou-stained anal smears were examined for cytological abnormalities, including those indicative of HPV infection or anal intraepithelial neoplasia (AIN). HPV DNA was detected by high stringency dot hybridisations using radiolabelled HPV 6, 11, 16 and 18 DNA probes. Visible anal condylomata, situated either externally or in the anal canal, were present in 26% of these men; 46% had cytological evidence of HPV infection, and 19% of the smears showed evidence of mild to moderate dysplastic changes (AIN I-II). Detectable HPV DNA was present in 40% of the anal scrapes. By combining these results, a total of 73 men (65%) were found to have at least one of the indicators of HPV infection. These data, together with that relating to HIV antibody, immune status and past or present infection with other STDs, was correlated with information obtained from a questionnaire administered to the patients at the time of their clinical examination.

CONCLUSIONS

In this study cytology was found to be slightly more sensitive than HPV DNA dot hybridisation for the detection of HPV infection in the anal canal, providing the full range of HPV-associated cytological changes were accepted as a basis for diagnosis. Clinical anal lesions were more likely to be detected in young men, men who had symptomatic HIV infection and those with a history of past anal wart infection. The latter group also had a higher incidence of cytologically apparent HPV infection in their anal smears. There was a significant association between the detection of HPV 16/18 and the presence of anal dysplasia, but there were no significant correlations between HPV infection or anal dysplasia and HIV antibody, immune function status, sexual practices or history of other STDs.

Anal human papillomavirus infection: a comparative study of cytology, colposcopy and DNA hybridisation as methods of detection

OBJECTIVE

To compare anal cytology, colposcopy and DNA hybridisation as methods of detecting anal HPV infection.

SUBJECTS AND DESIGN

Patients attending: (1) a genitourinary medicine (GUM) clinic with ano-genital warts; (2) a surgical out-patient department with anal fissure or haemorrhoids were examined for evidence of anal HPV infection.

RESULTS

Considering GUM clinic attenders, 17% (38/225) and 40% (90/225) had perianal or anal canal warts respectively. Colposcopic examination revealed anal acetowhite lesions without warts in 28% (63/225). Cytological evidence of HPV infection was found in 98%, 83%, and 90% of patients with anal canal warts, perianal warts and acetowhite lesions respectively. Anal intraepithelial neoplasia (AIN) was documented in 22% of patients with anal canal warts compared with 6% with perianal warts (p less than 0.01). HPV DNA was detected from the anal brushings of 71%, 50%, 32%, and 29% of patients with anal canal warts, perianal warts, acetowhite lesions and a normal anal examination respectively. HPV type 6/11 was detected in the majority of HPV positive samples. Considering surgical out-patient attenders with no history or signs of anal warts, 25% showed cytological evidence of anal HPV infection and HPV DNA was detected from anal brushings in 3% (2/71).

CONCLUSION

Anal examination with the colposcope is a useful method for detecting subclinical HPV infection. Anal cytology may prove helpful for detecting AIN, however, since koilocytosis was rarely seen, the specificity of the cytological criteria for anal HPV infection in the absence of AIN is uncertain. DNA analysis of anal brushings proved only moderately sensitive.