Comparison of PCR and hybrid capture methods for detection of human papillomavirus in injection drug-using women at high risk of human immunodeficiency virus infection

Sustained viral suppression and higher CD4+ T-cell count reduces the risk of persistent cervical high-risk human papillomavirus infection in HIV-positive women

BACKGROUND

Studies analyzing the impact of combination antiretroviral therapy (cART) on cervical infection with high-risk human papillomavirus (HR-HPV) have generated conflicting results. We assessed the long-term impact of cART on persistent cervical HR-HPV infection in a very large cohort of 652 women who underwent follow-up of HIV infection for a median duration of 104 months.

METHODS

Prospective cohort of HIV-infected women undergoing HIV infection follow-up who had HR-HPV screening and cytology by Papanicolaou smear performed yearly between 2002 and 2011.

RESULTS

At baseline, the median age was 38 years, the race/ethnic origin was sub-Sarahan Africa for 84%, the median CD4(+) T-cell count was 426 cells/µL, 79% were receiving cART, and the HR-HPV prevalence was 43%. The median interval of having had an HIV load of <50 copies/mL was 40.6 months at the time of a HR-HPV-negative test result, compared with 17 months at the time of a HR-HPV-positive test result (P < .0001, by univariate analysis). The median interval of having had a CD4(+) T-cell count of >500 cells/µL was 18.4 months at the time of a HR-HPV-negative test result, compared with 4.45 months at the time of a HR-HPV-positive test result (P < .0001). In multivariate analysis, having had an HIV load of <50 copies/mL for >40 months (odds ratio [OR], 0.81; 95% confidence interval [CI], .76-.86; P < .0001) and having had a CD4(+) T-cell count of >500 cells/µL for >18 months (OR, 0.88; 95% CI, .82-.94; P = .0002) were associated with a significantly decreased risk of HR-HPV infection.

CONCLUSION

Sustained HIV suppression for >40 months and a sustained CD4(+) T-cell count of >500 cells/µL for >18 months are independently and significantly associated with a decreased risk of persistent cervical HR-HPV infection.

Prevalence and Risk Factors Associated with Precancerous Cervical Cancer Lesions among HIV-Infected Women in Resource-Limited Settings

Objective. To assess the prevalence and identified associated risk factors for precancerous cervical cancer lesions among HIV-infected women in resource-limited settings in Kenya. Methods. HIV-infected women attending the ART clinic at the Nazareth Hospital ART clinic between June 2009 and September 2010. Multivariate logistic regression model with odds ratios and 95% confidence intervals (CI) were estimated after controlling for important covariates. Result. A total of 715 women were screened for cervical cancer. The median age of the participants was 40 years (range 18-69 years). The prevalence of precancerous lesions (CINI, CINII, CIN III, ICC) was 191 (26.7%). After controlling for other variables in logistic regression analysis, cervical precancerous lesions were associated with not being on ART therapy; whereby non-ART were 2.21 times more likely to have precancerous lesions than ART patients [(aOR) = 2.21, 95% CI (1.28-3.83)]. Conclusion. The prevalence of precancerous cervical lesions was lower than other similar settings. It is recommended that cancer screening of HIV-infected women should be an established practice. Availability and accessibility of these services can be done through their integration into HIV. Prompt initiation of HAART through an early enrollment into care has an impact on reducing the prevalence and progression of cervical precancerous lesions.

Determinants of newly detected human papillomavirus infection in HIV-infected and HIV-uninfected injection drug using women

BACKGROUND

We sought to identify factors associated with newly detected human papillomavirus (HPV) infection in a high-risk cohort of injection drug using women in Baltimore, MD.

METHODS

We studied 146 HIV-infected and 73 HIV-uninfected female participants in a 5-year prospective HIV natural history study. We examined the association of sexual and nonsexual risk factors and newly detected type-specific HPV infection as determined by consensus PCR between consecutive visits.

RESULTS

Newly detected HPV was more common among HIV-infected versus HIV-uninfected women (30% and 6%, respectively; P <0.01). Among the entire cohort, recent crack use (OR, 1.7; 95% CI, 1.1-2.6) and HIV infection/CD4 cell count were independent predictors for new HPV detection (HIV-uninfected as reference, OR, 4.6; 95% CI, 2.3-8.9, OR, 5.4; 95% CI, 2.8-10.3, and OR, 10.9; 95% CI, 5.5-21.7 for HIV-infected CD4 >500, 200-500, and <200, respectively). Among HIV-uninfected women, recent marijuana use was an independent predictor of newly detected HPV infection (OR, 3.5; 95% CI, 1.3-9.5).

CONCLUSIONS

Newly detected HPV clearly increased with greater immunosuppression in HIV-infected injection drug users. Larger studies of HIV-uninfected and infected high-risk individuals are needed to clarify the independent associations of crack and marijuana use with new (or reactivated) HPV infection.

HAART use in women with HIV and influence on cervical intraepithelial neoplasia: a clinical opinion

OBJECTIVES

Study the role of highly active antiretroviral therapy (HAART) in cervical disease in women with human immunodeficiency virus (HIV) and human papillomavirus (HPV) infections.

MATERIALS AND METHODS

A systematic review of current literature and the results summarized in the following headings: HIV and cytological evidence of disease, HIV and HPV, and HAART and HIV in women with HPV-associated cervical disease.

RESULTS

Limited data is available to study the influence of HAART on HPV-related cervical disease in women with HIV. There is evidence that the use of HAART may lead to immune restoration and thereby prevent severe recurrent HPV disease, thus influencing associated cervical disease.

CONCLUSIONS

Little data is available on HAART and its role in HPV-associated cervical disease in women with HIV. Immune restoration may decrease the severity and recurrence of HPV infection and potentially impact cervical disease. Population-based studies are needed to further evaluate the role of HAART in HPV associated cervical disease.

Factors associated with increased prevalence of human papillomavirus infection in a cohort of HIV-infected Brazilian women

OBJECTIVES

Human papillomavirus (HPV) infection is a major risk factor for cervical disease. Using baseline data from the HIV-infected cohort of Evandro Chagas Clinical Research Institute at Fiocruz, Rio de Janeiro, Brazil, factors associated with an increased prevalence of HPV were assessed.

METHODS

Samples from 634 HIV-infected women were tested for the presence of HPV infection using hybrid capture II and polymerase chain reaction. Prevalence ratios (PR) were estimated using Poisson regression analysis with robust variance.

RESULTS

The overall prevalence of HPV infection was 48%, of which 94% were infected with a high-risk HPV. In multivariate analysis, factors independently associated with infection with high-risk HPV type were: younger age (<30 years of age; PR 1.5, 95% confidence interval (CI) 1.1-2.1), current or prior drug use (PR 1.3, 95% CI 1.0-1.6), self-reported history of HPV infection (PR 1.2, 95% CI 0.96-1.6), condom use in the last sexual intercourse (PR 1.3, 95% CI 1.1-1.7), and nadir CD4+ T-cell count <100cells/mm(3) (PR 1.6, 95% CI 1.2-2.1).

CONCLUSIONS

The estimated prevalence of high-risk HPV-infection among HIV-infected women from Rio de Janeiro, Brazil, was high. Close monitoring of HPV-related effects is warranted in all HIV-infected women, in particular those of younger age and advanced immunosuppression.

Prevalence and distribution of HPV genotypes among HIV-infected women in Zambia

We screened 145 HIV-infected non-pregnant women at a tertiary care centre in Lusaka, Zambia. Liquid-based cytology and human papillomavirus (HPV) genotyping with PGMY09/11 biotinylated primers (Roche Linear Array® HPV genotyping test) maximised sensitivity of cytology and HPV assessments. Among high-risk (HR) types, HPV 52 (37.2%), 58 (24.1%) and 53 (20.7%) were more common overall than HPV 16 (17.2%) and 18 (13.1%) in women with high-grade squamous intraepithelial lesions or squamous cell carcinoma (SCC) on cytology. High-risk HPV types were more likely to be present in women with CD4⁺ cell counts <200 μ l⁻¹ (odds ratios (OR): 4.9, 95% confidence intervals (CI): 1.4–16.7, P=0.01) and in women with high-grade or severe cervical cytological abnormalities (OR: 8.0, 95% CI: 1.7–37.4, P=0.008). Human papillomavirus diversity in high-grade lesions and SCC on cytology suggests that HPV 16- and 18-based vaccines may not be adequately polyvalent to induce protective immunity in this population.

Relationships of Human Papillomavirus Type, Qualitative Viral Load, and Age with Cytologic Abnormality

Persistent cervical infections with carcinogenic human papillomaviruses (HPV) cause virtually all cervical cancer. Cytologic abnormalities are the manifestations of HPV infections used to identify women at risk. To compare the potential of the full range of anogenital HPV genotypes to induce cytopathic effects, we examined the influences of HPV type, viral load, and age on cytopathology among 1,222 women having a single HPV type at enrollment into a 10,000-woman population-based study in Costa Rica. Cervical specimens were tested for approximately 40 HPV types by MY09/MY11 L1 primer PCR and type-specific dot blot hybridization. Types were organized by phylogenetic species and cancer risk. PCR signal strength served as a qualitative surrogate for viral load. Overall, 24.8% [95% confidence interval (95% CI), 22.4-27.3] of single prevalent HPV infections had concurrent abnormalities (atypical squamous cells or worse) ranging from 0.0% to 80.0% based on HPV type. Noncarcinogenic alpha3/alpha15 types, although highly prevalent, uncommonly caused cytologic abnormalities (13.1%; 95% CI, 9.8-17.0). In contrast, one quarter to nearly one half of infections with a single major carcinogenic species type (alpha9/alpha11/alpha7/alpha5/alpha6) produced abnormalities. Greater abnormalities were observed with increasing qualitative viral load of carcinogenic types; fewer abnormalities were observed among older women (>54 years). A high percentage (46.2%) of detected abnormalities in women infected with HPV16 or related alpha9 types were high grade or worse, consistent with strong carcinogenicity, compared with 10.7% in women infected with alpha7 types, including HPV18, a major cause of adenocarcinoma. The lack of evident severe abnormalities associated with HPV18 and related HPV types might have implications for screening for poorly detected glandular and alpha7-related lesions.

High level of correlation of human papillomavirus-16 DNA viral load estimates generated by three real-time PCR assays applied on genital specimens

Human papillomavirus-16 (HPV-16) viral load could be a biomarker predictive of the presence of high-grade cervical lesions. Recently, several real-time PCR assays have been developed to accurately measure HPV-16 viral load. However, results from various reports using these assays cannot be compared because interassay test correlation has not been documented. The variability of HPV-16 DNA quantitation was assessed by comparing three real-time PCR assays (HPV-16 L1, HPV-16 E6, and HPV-16 E6 PG) applied on 144 genital samples (125 cervicovaginal lavages and 19 specimens collected using vaginal tampons) obtained from 84 women (66 HIV seropositive and 18 HIV seronegative). Correlation was greater between the HPV-16 E6 assays [correlation coefficient (rho) = 0.92] than between each E6 assay and HPV-16 L1 assay (rho = 0.83 and 0.84, respectively). The median HPV-16 copies measured by HPV-16 E6 PG (14,609 HPV-16 copies/2 muL sample) and HPV-16 E6 (18,846 HPV-16 copies/2 muL) were similar (P = 0.27) but were both greater than the median HPV-16 copies measured with the L1 assay (4,124 HPV-16 copies/2 muL; P < 0.001). Correlations between HPV-16 E6 assays were similar for samples containing non-European (rho = 0.93) or European (rho = 0.95) variants. However, the correlation between HPV-16 L1 and HPV-16 E6 PG or HPV-16 E6 was lower for specimens containing non-European variants (rho = 0.80 and 0.76, respectively) compared with specimens containing European variants (rho > 0.85). HPV-16 DNA quantity estimated with the three assays was comparable although lower with the HPV-16 L1 assay. The level of correlation depended on viral polymorphism, viral load, and cervical disease status.

High levels of HPV-16 DNA are associated with high-grade cervical lesions in women at risk or infected with HIV

OBJECTIVE

To examine associations between levels of episomal and integrated human papillomavirus (HPV) 16 DNA and the grade of cervical disease.

DESIGN

Cross-sectional data were obtained from a cohort of women with and without HIV infection and with high-risk sexual behaviour.

METHODS

Episomal and integrated HPV-16 DNA loads were measured in cervicovaginal lavages collected from 75 women (58 HIV seropositive, 17 HIV seronegative) using real-time polymerase chain reaction assays, controlling for cell content and the presence of inhibitors.

RESULTS

HPV-16 viral loads were significantly higher in women with high-grade squamous intraepithelial lesions (n = 6) than in women with normal cytology (n = 44), whether total (10(8.28) versus 10(5.10) HPV-16 DNA copies/microg DNA), episomal (10(7.99) versus 10(4.61)) or integrated (10(7.95) versus 10(4.77)) HPV-16 viral loads were measured (P < 0.02 for each comparison). Thirty-nine women had colposcopy [11 normal cervix, 16 cervical intraepithelial neoplasia (CIN) 1, six CIN 2, six CIN 3] and 24 additional women had three consecutive normal cytology smears. Controlling for age, race, CD4 cell count and HIV status, total (OR 3.5, 95% CI 1.2-10.4; P = 0.02), episomal (OR 2.9, 95% CI 1.2-7.4; P = 0.02,) and integrated (OR 1.6, 95% CI 1-2.6; P = 0.05) HPV-16 DNA loads were significantly associated with CIN 2,3, but the differences between CIN 1 and CIN 2,3 were not significant (P > 0.06). A greater amount of cellular DNA was collected from women with CIN 2,3 (P = 0.007).

CONCLUSION

Higher HPV-16 DNA loads are associated with cervical lesions detected by either histology or cytology. No additional information is gained by measuring integrated or episomal over total HPV-16 DNA loads.

Human papillomavirus type 16 viral load is higher in human immunodeficiency virus-seropositive women with high-grade squamous intraepithelial lesions than in those with normal cytology smears

Human papillomavirus type 16 (HPV-16) viral load in cervicovaginal lavage samples collected from 66 human immunodeficiency virus-seropositive women was inversely correlated with blood CD4 count (P = 0.002). HPV-16 viral load was 81-fold higher in women with cervical smears suggestive of high-grade lesions (median, 4,425,883 copies/ micro g of DNA) than in women with normal smears (median, 54,576), controlling for age (P = 0.006).

Prevalence of human papillomavirus genotypes in women from three clinical settings

Prevalence of 27 human papillomavirus (HPV) genotypes was assessed in 1,331 women in three clinical settings: Family planning clinic (low-risk HIV-, n = 202, 21.3% HPV+), colposcopy clinic (high-risk HIV-, n = 854, 34.3% HPV+), and HIV outpatient clinic (HIV+, n = 275, 48.7% HPV+). Compared to women from both family planning and colposcopy clinics, HIV+ women revealed significantly higher prevalence of infection with oncogenic, non-oncogenic, and multiple HPV types. HPV types 52 and 51 were most prevalent in the low-risk HIV- women, whereas in the high-risk HIV- women, HPV types 16, 52, 58, and 35 were most prevalent. Interestingly, in the HIV+ women, less characterized types 83, 53, and 54 were most prevalent. The distinct profiles of genotype prevalence persisted after stratification by Pap smear status. After adjustment for concurrent infections with other types, HPV type 51 in the low-risk HIV- women, and types 16, 35, 39, 45, 52, and 58 in the high-risk HIV- women were significantly associated with cytologic abnormalities (exact P < 0.05). In HIV+ women across CD4 cell count strata, HPV types 42, 16, and 82 revealed significant decreasing trends with increasing CD4 counts (exact P for trend < 0.05). These data suggest distinct genotypic prevalence profiles in women at diverse risk for cervical cancer. The association of several genotypes with cytologic abnormalities underscores the need for vaccines targeting a wide range of HPV types.

The impact of HIV infection and immunodeficiency on human papillomavirus type 6 or 11 infection and on genital warts

BACKGROUND

HIV infection and associated immunodeficiency are known to alter the course of human papillomavirus (HPV) infections and of associated diseases.

GOAL

This study investigated the association between HIV and HPV and genital warts.

STUDY DESIGN

HPV testing and physical examinations were performed in two large prospective studies: the Women's Interagency HIV Study (WIHS) and the HIV Epidemiology Research Study (HERS). Statistical methods incorporating dependencies of longitudinal data were used to examine the relationship between HIV and HPV and genital warts.

RESULTS

A total of 1008 HIV-seronegative and 2930 HIV-seropositive women were enrolled in the two studies. The prevalence of HPV 6 or 11 was 5.6 times higher in HIV-seropositive women in the WIHS and 3.6 times higher in the HERS. Genital wart prevalence increased by a factor of 3.2 in the WIHS and 2.7 in the HERS in HIV-seropositive women. In the WIHS, infection with HPV type 6 or 11, in comparison with no HPV infection, was associated with odds of genital wart prevalence of 5.1 (95% CI: 2.9-8.8), 8.8 (95% CI: 6.1-12.8), and 12.8 (95% CI: 8.8-18.8) in HIV-seronegative women, HIV-seropositive women with > or =201 CD4 cells/microl, and HIV-seropositive women with < or =200 CD4 cells/microl, respectively. In the HERS, infection with HPV type 6 or 11 was associated with odds of 2.7 (95% CI: 1.6-4.6), 4.9 (95% CI: 3.2-7.7), and 5.3 (95% CI: 3.3-8.5) in these same groups. Other HPV types showed a similar dose-response relation, but of substantially lower magnitude and statistical significance.

CONCLUSIONS

HIV infection and immunodeficiency synergistically modified the relation between HPV 6 or 11 infection and genital wart prevalence.

Quantitation of human papillomavirus 16 E6 and E7 DNA and RNA in residual material from ThinPrep Papanicolaou tests using real-time polymerase chain reaction analysis

BACKGROUND

The detection of specific human papillomavirus 16 (HPV-16) E6 and E7 oncogene transcripts may be a sensitive indicator of the direct involvement of viral oncogenes in the development of cervical neoplasia and carcinoma. The goal of this study was to determine the potential clinical uses of real-time polymerase chain reaction (PCR) and reverse transcription-PCR (RT-PCR) methods for evaluating HPV-16 E6 and E7 oncogene expression.

METHODS

ThinPrep cervical samples were tested for expression of oncogenes of HPV-16 by real-time PCR or RT-PCR analysis and were compared with detection of expression by conventional PCR and RT-PCR analysis. Both sets of results were correlated with the cytologic diagnosis of the cervical samples.

RESULTS

The presence of HPV-16 E6 and E7 DNA and RNA was observed only in HPV-16 positive cervical carcinoma cell lines but not in HPV-18 positive or HPV negative cell lines. The percentage positive for HPV-16 E6 or E7 DNA in a series of ThinPrep cervical cytologic samples (n = 348 samples) was 0% for negative samples (n = 45 samples), 9.7% for atypical squamous cells of undetermined significance (ASCUS; n = 144 samples), 16.9% for low-grade squamous intraepithelial lesion (LSIL; n = 118 samples), and 51.2% for high-grade intraepithelial lesion (HSIL; n = 41 samples). The copy numbers per nanogram for both DNA and RNA E6 and E7 were increased significantly as severity of the lesions progressed from ASCUS to HSIL, and RNA copy numbers were a more sensitive indicator of HPV-16 E6 and E7 expression than DNA copy numbers. The increase in copy numbers took place in a stepwise fashion from ASCUS, to LSIL, to HSIL.

CONCLUSIONS

The detection of HPV-16 E6 and E7 expression by real-time RT-PCR or PCR analysis in ThinPrep cervical cytologic specimens may serve as a quick, reliable, and sensitive tool to identify a subset of patients who express HPV-16 oncoproteins.

Cost effectiveness of human papillomavirus testing to augment cervical cancer screening in women infected with the human immunodeficiency virus

PURPOSE

To determine the cost effectiveness of incorporating molecular testing for high-risk types of human papillomavirus into a cervical cancer screening program for women infected with the human immunodeficiency virus (HIV).

SUBJECTS AND METHODS

We developed a Markov model to simulate the natural history of cervical cancer precursor lesions in HIV-infected women. Probabilities of progression and regression of cervical lesions were conditional on transient or persistent infection with human papillomavirus, as well as stage of HIV and effectiveness of antiretroviral therapy. Incorporating data from prospective cohort studies, national databases, and published literature, the model was used to calculate quality-adjusted life expectancy, life expectancy, lifetime costs, and incremental cost-effectiveness ratios for two main strategies: targeted screening-human papillomavirus testing is added to the initial two cervical cytology smears obtained after an HIV diagnosis and subsequent screening intervals are modified based on the test results; and universal screening-no testing for human papillomavirus is performed, and a single cytology screening interval is applied to all women.

RESULTS

In HIV-infected women on anti-retroviral therapy, a targeted screening strategy in which cervical cytology screening was conducted every 6 months for women with detected human papillomavirus DNA, and annually for all others, cost $10,000 to $14,000 per quality-adjusted life year gained compared with no screening. A universal screening strategy consisting of annual cervical cytology for all women was 15% less effective and had a less attractive cost-effectiveness ratio. Targeted screening remained economically attractive in multiple sensitivity analyses, although when the overall incidence of cervical cancer precursor lesions was lowered by 75%, the screening interval for women with detected human papillomavirus DNA could be widened to 1 year.

CONCLUSIONS

Adding human papillomavirus testing to the two cervical cytology smears obtained in the year after an HIV diagnosis, and modifying subsequent cytology screening intervals based on the results, appears to be an effective and cost-effective modification to current recommendations for annual cytology screening in HIV-infected women.

Human papillomavirus-associated cervical cytologic abnormalities among women with or at risk of infection with human immunodeficiency virus

OBJECTIVE

Correlates of abnormal human immunodeficiency virus cervical cytologic findings were examined among women infected with human immunodeficiency virus and uninfected women.

STUDY DESIGN

We performed a cross-sectional analysis of baseline data on demographically similar women with infection or risk factors for it.

RESULTS

Among 1050 women without hysterectomy, squamous intraepithelial lesions were more common among women infected with human immunodeficiency virus than among uninfected women (18.8% vs 5.3%; P <.001). In multivariate analysis the association of squamous intraepithelial lesions with human papillomavirus infection was strong; adjusted prevalence ratios were 27 for high-risk, 25 for intermediate-risk, and 10 for low-risk types (95% confidence intervals, 12-58, 12-54, and 4-25, respectively). Much lower adjusted prevalence ratios were seen for the only other factor significantly associated with squamous intraepithelial lesions, namely, infection with human immunodeficiency virus in conjunction with a reduced CD4(+) cell count. Adjusted prevalence ratios were 1.9 for CD4(+) cell counts <200 and 1.6 for CD4(+) cell counts between 200 and 500 (95% confidence intervals, 1.2-3.0 and 1.0-2.5, respectively). Adjusted attributable fractions calculated for this study population indicated that if both human immunodeficiency virus and human papillomavirus were removed, 47.6% of the observed lesions with atypical squamous cells of uncertain significance and 93.4% of the observed squamous intraepithelial lesions would be prevented.

CONCLUSION

Squamous intraepithelial lesions are more common among human immunodeficiency virus-infected women and are associated most commonly with high- and intermediate-risk human papillomavirus types and secondarily with human immunodeficiency virus-associated immune compromise.

Investigation of the association of esophageal carcinoma with human papillomaviruses

The role of human papillomavirus (HPV) in esophageal cancers was evaluated in patients seen at Johns Hopkins University Hospital. Frozen esophageal tumor tissues from 22 cases with squamous cell carcinoma (SCC) and 24 cases with adenocarcinoma (AC), diagnosed between 1988 and 1998, were assayed for HPV sequences by reverse line blot polymerase chain reaction. HPV sequences (HPV-54) were detected in a single specimen; the other 45 specimens were negative. The HPV sequences in the positive specimen may represent infection of the epithelium. Our results suggest that genital HPVs may sometimes infect the esophagus, but there is no evidence to indicate that these infections contribute substantially to the development of esophageal cancer in North America.

Nucleotide sequence and characterization of human papillomavirus type 83, a novel genital papillomavirus

Studies of human papillomaviruses (HPV) are hampered by the lack of a conventional culture system, because HPV completes its life cycle only in fully differentiated human tissue. To overcome this obstacle, the athymic mouse xenograft system has been used to study the pathogenesis of a limited number of HPV types. We recently reported the propagation of a novel HPV type in the mouse xenograft system and the cloning of its genome. Consensus primer PCR had previously identified this virus as MM7, LVX82, or PAP291. Here we report the nucleotide sequence of the 8104-bp genome of this virus, now called HPV 83. HPV 83 is most closely related to HPV 61 and HPV 72, placing it in the papillomavirus genome homology group A3. Based on limited epidemiological data, the histological appearance of infected human foreskin implants, and the structure of the predicted HPV 83 E7 protein, this virus is probably of at least intermediate cancer risk. Like other papillomaviruses, HPV 83 produces an E1 E4, E5 transcript, but the position of the splice acceptor differs from that of other HPVs. The presence of an E5 open reading frame in the HPV 83 genome is uncertain; the most likely candidate to be the HPV 83 E5 protein has some structural similarity to the bovine papillomavirus 1 E5 oncoprotein, and is unlike most other HPV E5 proteins. HPV 83 is a relatively prevalent genital papillomavirus that has the largest genome of any characterized HPV and several other novel structural features that merit further study.

Comparative evaluation of first- and second-generation digene hybrid capture assays for detection of human papillomaviruses associated with high or intermediate risk for cervical cancer

In the present study we comparatively evaluated the first- and second-generation Digene Hybrid Capture assays for detection of human papillomaviruses (HPV) associated with high or intermediate risk for cervical cancer in cervical specimens. Concordant results were obtained with 468 of 483 (96.8%) specimens. All 15 specimens which gave repeatedly discordant results were positive by the second-generation test only, and 14 of them tested PCR positive. The enhanced sensitivity of the second-generation assay is mainly a result of the reformulation of hybridization reagents and, to a lesser extent, a result of the addition of new HPV probes.

Prevalence of risk factors associated with human papillomavirus infection in women living with HIV. Canadian Women's HIV Study Group

BACKGROUND

Concurrent infection with HIV and human papillomavirus (HPV) in women is associated with increased rates of cervical dysplasia and shorter survival following the development of cervical cancer. The authors examined risk factors for HPV infection at study entry in HIV-positive women enrolled in the Canadian Women's HIV Study, a prospective open cohort study.

METHODS

Subjects eligible for this analysis included the 375 HIV-positive women in the Canadian Women's HIV Study for whom HPV test results were available. Questionnaires on behavioural and clinical information, Pap smears, cervicovaginal lavage specimens and vaginal tampon specimens for HPV detection and typing by polymerase chain reaction were obtained at study entry.

RESULTS

Overall, 67.2% (252/375) of the women were HPV-positive; the global prevalence of intermediate- and high-risk oncogenic HPV types was 49.1% (184/375). Women with squamous cell dysplasia (32/294) were more likely to have HPV infection than those without dysplasia (90.6% v. 62.6%; p = 0.002). Multivariate logistic regression analysis, with adjustment for number of lifetime partners and history of STD, revealed that the following risk factors were independently associated with HPV infection: CD4 count of less than 0.20 x 10(9)/L (adjusted odds ratio [OR] 1.99 [95% confidence interval (Cl) 1.17-3.37 (p = 0.011)]), non-white race (adjusted OR 2.00 [95% Cl 1.17-3.42 (p = 0.011)]), inconsistent condom use in the 6 months before study entry (adjusted OR 2.02 [95% Cl 1.16-3.50 (p = 0.013)]), and lower age, with women age 30-39 years (adjusted OR 0.51 [95% Cl 0.30-0.87 (p = 0.013)]) and age 40 years or older (adjusted OR 0.52 [95% Cl 0.26-1.01 (p = 0.052)]) compared with women less than 30 years of age.

INTERPRETATION

Close monitoring for HPV-related effects is warranted in all HIV-positive women, particularly younger, non-white women who do not always use condoms. Counselling for women living with HIV, particularly younger women, should emphasize the importance of regular cytological screening, with increasing frequency as the CD4 count falls.

Comparison of PCR- and hybrid capture-based human papillomavirus detection systems using multiple cervical specimen collection strategies

This study compared the performances of three human papillomavirus (HPV) detection tests with specimens collected by three alternative procedures. The HPV tests included the Hybrid Capture Tube test (HCT), the microplate-based Hybrid Capture II test (HC II), and the MY09-MY11 L1 consensus primer PCR-based assay. Initial cervical specimens were collected from study subjects with a broom device, and after Papanicolaou smears were made, residual specimens were placed into PreservCyt (PC), a liquid cytology medium. A second specimen was collected from each subject and placed into Digene Specimen Transport Medium (STM). The device for collection of the second specimen alternated with consecutive subjects between a conical cytology brush and a Dacron swab. At the 1.0-pg/ml cutoff, the results of the HC II agreed well with those of the PCR. Specifically, when PCR data were restricted to the types found by the HC II (HPV types 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, and 68), there was greater than 90% agreement between the HC II and PCR results with both STM and PC. At a lower cutoff (0.2 pg/ml), HC II-positive results increased further, especially when the test was applied to the PC specimens. However, false-positive HC II results were more often observed at the 0.2-pg/ml cutoff. HC II yielded the highest HPV positivity with specimens placed into PC, followed by specimens collected with a conical brush and placed into STM and, last, by those collected with a Dacron swab and placed into STM. Our results demonstrate the utility of both the STM and PC specimen collection methods and show good agreement between the HC II and PCR.

The clinical utility of viral quantitation using molecular methods

BACKGROUND

The quantitation of viral nucleic acids in biological fluids has become increasingly desirable over the past several years. To this end, a number of quantitative molecular procedures have been developed.

OBJECTIVES

The objective was to review the current literature on the molecular techniques used in the quantitation of viral nucleic acids and to assess the appropriateness of these methods for clinical use.

RESULTS

Assays involving both target and signal amplification are now available for the accurate and precise quantitation of viral burden in infected patients. These methods include quantitative polymerase chain reaction (PCR), branched chain signal amplification (bDNA), nucleic acid sequence-based amplification (NASBA) and the SHARP signal and hybrid capture systems. Our understanding of the natural history and pathogenesis of viruses such as the human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV), cytomegalovirus (CMV) and Epstein-Barr virus (EBV) may be greatly facilitated by accurate determinations of viral and infected cell burden. Quantitation of viral load in infected individuals may also be useful to assess disease progression, monitor the efficacy of therapy and to predict treatment failure and the emergence of drug-resistant viruses.

CONCLUSION

Precise, accurate and reproducible quantitation of viral load is now feasible. Molecular assays for viral quantitation should have a considerable impact on medical research and clinical care.

The future of HPV testing in clinical laboratories and applied virology research

BACKGROUND

Human papillomaviruses (HPV) are now considered etiologic agents of cancer of the uterine cervix. Adjunctive diagnostic procedures for the detection of HPV infection could increase the sensitivity of primary and secondary screening of cervical cancer. HPV testing could also improve the specificity of screening programs resulting in avoidance of overtreatment and saving of costs for confirmatory procedures.

OBJECTIVES

To review the rationale of HPV testing in genital diseases and the potential applications of HPV DNA detection methods for clinical and epidemiological purposes.

RESULTS

Progression of HPV infection is associated with the persistence of HPV infection, involvement of high-risk HPV types, high HPV viral load in specimens, integration of viral DNA and possibly the presence of cofactors. The design of HPV diagnostic tests will need to take into account these parameters of disease progression. HPV DNA detection techniques based on signal-amplification are standardized, commercially available and detect several high-risk HPV types. They increase the sensitivity of screening for high-grade and low-grade lesions. Although they may yield false-negative results in the presence of significant HPV-related disease, new test formats could resolve this weakness. Amplification techniques are ideal instruments for epidemiologic purposes since they minimize misclassification of HPV infection status and allow for the detection of low viral burden infections. They are currently not readily applicable to diagnostic laboratories.

CONCLUSIONS

Before recommending HPV testing, prospective trials of untreated LSIL with HPV testing as well as the determination of the efficacy and cost-effectiveness of novel HPV tests, need to be completed.