Reduction of mother-to-child transmission of HIV infection: non-pharmaceutical interventions and their implementation

Human papillomavirus DNA in men who have sex with men: type-specific prevalence, risk factors and implications for vaccination strategies

Background:

Human papillomavirus (HPV) vaccination of girls will have relatively little effect on HPV-related disease in men who have sex with men (MSM). We determined HPV prevalence and risk factors in MSM to inform the potential effectiveness of vaccinating MSM.

Methods:

Cross-sectional study of 522 MSM aged 18–40 attending a London sexual health clinic who completed a computer-assisted self-interview. Urine and two swabs (anal and penile/scrotal/perianal) were collected and tested using an in-house Luminex-based HPV genotyping system.

Results:

Prevalence of DNA of the vaccine-preventable HPV types in ano-genital specimens of men was 87/511 (17.0%), 166/511 (32.5%) and 232/511 (45.4%) for the bivalent (HPV16/18), quadrivalent (HPV6/11/16/18) and nonavalent (HPV6/11/16/18/31/33/45/52/58) vaccine types, respectively. A total of 25.1% had one of the quadrivalent types, and 7.4% had 2+ types. Median age at first anal sex was 19 (IQR 17–23) and at first clinic attendance was 24 (IQR 20–27). The increase in the odds of any HPV infection per year of age was 4.7% (95% CI 1.2–8.4).

Conclusions:

On the basis of the current infection status, most MSM, even among a high-risk population attending a sexual health clinic, are not currently infected with the vaccine-type HPV. A targeted vaccination strategy for MSM in the UK could have substantial benefits.

Rapid identification of infants for antiretroviral therapy in a resource poor setting: the Kenya experience

In Kenya, HIV diagnosis is not routinely carried out in infants, and yet rapid diagnosis could improve access to lifesaving interventions. A cheap and readily accessible service can resolve this problem, if feasible. In this pilot study the feasibility and costs of provision of an infant HIV diagnosis service in Kenya are evaluated. Dried blood spots (DBS) were collected from infants exposed to HIV, sent to a central testing laboratory and tested using the Roche Amplicor v. 1.5 DNA PCR kit. The results were then dispatched to health facilities within a week. A total of 15.4% of the samples tested HIV+ despite the widespread access to prevention of mother to child transmission (PMTCT) programs in Kenya. The cost per test at 21.50 USD is prohibitive and will limit access to diagnosis. It remains to be seen whether the increase in testing will immediately lead to an increase in access to antiretroviral therapy (ART) services for infants.

Immunoreactivity of p16 in anal cytology specimens: histologic correlation

BACKGROUND

Cytology has been proposed as a potential screening tool in the evaluation of squamous anorectal disease in view of the morphologic similarities between anal and cervical squamous lesions. Previous studies have demonstrated that p16 overexpression correlates with the degree of dysplasia in the uterine cervix with promising results. Due to potential diagnostic pitfalls in anal cytology, p16 overexpression in these specimens was studied.

METHODS

Patients with anorectal cytology who underwent follow-up biopsy within 1 year were selected. Forty-three anorectal cytologic specimens from 29 patients were selected. One slide of each case was destained. Avidin-biotin immunocytochemical studies with the monoclonal antibody CINtec p16(INK4a) were performed. The results of the p16 immunostaining were correlated with the histologic findings.

RESULTS

Twenty-eight of the 43 cases demonstrated the presence of squamous cells immunoreactive for p16 in cytology specimens. The p16-positive cells were identified in cases of low-grade squamous intraepithelial lesion (LSIL) (n = 3 cases), high-grade squamous intraepithelial lesion (HSIL) (n = 22 cases), and invasive squamous carcinoma (n = 1 case), and in 2 cases with negative follow-up biopsies. No cell immunoreactive for p16 was found in 15 cases (5 benign cases and 10 cases with either LSIL or HSIL). The sensitivity and specificity of p16 immunoreactivity in the detection of anal intraepithelial neoplasia or carcinoma were 72% and 71%, respectively. The positive and negative predictive values were 93% and 33%, respectively.

CONCLUSIONS

The presence of p16 immunoreactivity is a good predictor of dysplasia in anal specimens. However, the sensitivity and specificity of this marker are not high.

Anorectal cytology as a screening tool for anal squamous lesions: cytologic, anoscopic, and histologic correlation

BACKGROUND

Anorectal cytology has been increasingly used as a screening method for anal squamous lesions, particularly in high-risk, homosexual, patients with human immunodeficiency virus infection. The diagnostic cytologic, anoscopic, and histologic criteria bear some resemblance to the criteria used in cervicovaginal samples with few differences. It is important to recognize these differences because they can lead to an erroneous diagnosis of dysplasia and unnecessary procedures.

METHODS

Seventy-eight anorectal cytology specimens from 51 patients were reviewed blindly. Of the 51 patients, 33 were HIV positive. The cytology specimens consisted of 75 ThinPrep (Cytyc, Boxborough, MA) and 3 conventional Papanicolaou-stained smear specimens. The revised diagnosis was compared with the original diagnosis, corresponding histology specimens, and anoscopic results, when available.

RESULTS

Six specimens were unsatisfactory for review. The revised diagnosis was negative in 15 patients, atypical squamous cells of undetermined significance in 3 patients, low-grade squamous intraepithelial lesions in 24 patients, high-grade squamous intraepithelial lesions in 28 patients, and squamous cell carcinoma (SQC) in 2 patients. Five patients with an original diagnosis of SQC had the diagnosis revised upon review of their specimens. It is noteworthy that these five specimens showed the presence of atypical parakeratotic cells. Thirty-two patients had anoscopic evaluation and 30 patients had histologic correlation. Twenty-seven patients with abnormal anoscopic findings had confirmed abnormal histologic findings. Twenty- five of the 32 (78%) patients had abnormal cytology that correlated with abnormal anoscopic findings.

CONCLUSIONS

Anorectal cytology is an accurate method for screening patients for anal squamous lesions. Atypical parakeratotic cells represent a potential pitfall. Anoscopy is important in confirming the presence of a lesion, but only a biopsy can accurately determine the grade of a lesion.

Global impact of human immunodeficiency virus and AIDS

This review provides information on the epidemiology, economic impact, and intervention strategies for the human immunodeficiency virus (HIV)/AIDS pandemic in developing countries. According to the World Health Organization and the Joint United Nations Programme on HIV/AIDS (UNAIDS) at the end of 1999, an estimated 34.3 million people were living with HIV/AIDS. Most of the people living with HIV, 95% of the global total, live in developing countries. Examples of the impact of HIV/AIDS in Africa, Asia, Latin America, the Caribbean, and the Newly Independent States provide insight into the demographics, modes of exposure, treatment and prevention options, and the economic effect of the epidemic on the global community. The epidemic in each region of the world is influenced by the specific risk factors that are associated with the spread of HIV/AIDS and the responses that have evolved to address it. These influences are important in developing HIV/AIDS policies and programs to effectively address the global pandemic.

Perianal Bowen's disease and anal intraepithelial neoplasia: review of the literature

PURPOSE

The aim of this study was to review the literature with regard to perianal Bowen's disease and anal intraepithelial neoplasia.

METHODS

A literature review was conducted from 1960 to 1999 using MEDLINE.

RESULTS

Perianal Bowen's disease and anal intraepithelial neoplasia are precursors to squamous carcinoma of the anus. They are analogous to and are associated with cervical and vulvar intraepithelial neoplasia, and have human papillomavirus as a common cause. Biopsy and histopathologic examination is required for diagnosis and to distinguish other perianal dermatoses. Treatment options range from aggressive wide local excision of all disease with negative margins to observation alone for microscopic lesions not visible to the naked eye. The disease has a proclivity for recurrence and recalcitrance.

CONCLUSIONS

Most surgeons caring for patients with perianal Bowen's disease and high-grade anal epithelial neoplasia use wide local excision, with an effort to obtain disease-free margins. Some authors have reported the advantages of ablative procedures such as laser ablation and cryotherapy. Microscopic disease found serendipitously in hemorrhoidectomy specimens can probably be treated conservatively with serial examinations alone. There is a lack of controlled data supporting an optimal treatment strategy. A multicenter controlled study comparing wide local excision with ablative procedures may be warranted.