Less frequent Pap tests may be safe for some with HIV

For HIV-positive women with functional immune systems, normal Pap test results and who test negative for Human papilloma virus (HPV), the interval between Pap tests may safely be extended to three years, new study results suggest.

Currently, HIV-positive women are advised to have two Pap smears six months apart after their initial HIV diagnosis, and then annually if results are normal. HIV-infected women who are immunocompromised - as indicated by low CD4 counts, are at increased risk of cervical cancer. HPV infection is linked with most cases of cervical cancer.

To test the theory that longer intervals between Pap tests may be safe in HIV-infected women, Dr. Tiffany G. Harris, at the Albert Einstein College of Medicine in Bronx, New York, and associates followed 855 HIV-positive and 343 HIV-negative women.

At the start of the study the average age was 35 years and the women had normal Pap test results.

All of the women underwent Pap tests and HPV screening every six months for seven years. There were no cases of cervical cancer during the study, Harris' team reports in the Journal of the American Medical Association.

After two years, the incidence of abnormal Pap test results was similar between HIV-positive subjects who had CD4 counts higher than 500 cells per microliter and who tested negative for HPV, and the HIV-negative subjects. These HIV-positive women continued to have a low rate of abnormal Pap tests for three years.

However, the researchers note that HIV-positive women with CD4 counts of less than 500 cells per microliter and who test positive for HPV infection were significantly more likely to have abnormal Pap smear results after two years.

The authors advise that clinical trials are needed to confirm their results before any changes in testing strategy can be recommended.

SOURCE: Journal of the American Medical Association, March 23/30, 2005.