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author:("rings, Allen")
Cancer Epidemiology  2011;36(3):263-269.
Cervical cancer is the most common cancer in women in low-income countries. Although cervical cancer incidence and mortality is higher in HIV-positive women, resource limitations restrict the implementation of systematic screening programs in these women. We explored the potential for targeted screening by assessing the prevalence, severity and predictors of cervical squamous intra-epithelial lesions (SILs) in HIV-positive women in Cameroon.
Methods and findings
We conducted a cross-sectional study of women on antiretroviral therapy in Cameroon. Socio-demographic, behavioral, and clinical information was obtained from eligible women. Cervical exfoliated cells were then collected, a conventional cytology performed and epithelial lesions classified according to the Bethesda 2001 system.
A total of 282 women, aged 19 to 68 years, were enrolled in this study. The median CD4 count was 179 cells/microliter (interquartile range: 100 to 271). SILs were detected in 43.5% of the 276 women with satisfactory samples: including atypical squamous cells of unknown significance (ASCUS) 0.7%, low-grade SIL (LSIL) 25.0%, atypical squamous cells, cannot exclude high grade lesions (ASC-H) 14.5%, and high-grade SIL (HSIL) 3.3%. None of the demographic or clinical characteristics considered significantly predicted the presence of any SILs or the presence of severe lesions requiring colposcopy.
The prevalence of SIL in women on antiretroviral therapy in Cameroon was high underscoring the need for screening and care in this population. In the absence of any accurate demographic or clinical predictor of SIL, targeted screening does not seem feasible. Alternative affordable screening options need to be explored.
PMCID: PMC3288586  PMID: 22047636
Cervical neoplasm; HIV; Screening; Cameroon; Epidemiology
2.  Age trends in the prevalence of cervical squamous intraepithelial lesions among HIV-positive women in Cameroon: a cross-sectional study 
BMC Research Notes  2012;5:590.
Cervical squamous intra-epithelial lesions (SIL) are more frequent in HIV-positive women overall. However the appropriate age at which to begin and end cervical cancer screening for early detection of lesions in HIV-positive women is not clear. We assessed the age-specific prevalence of any SIL and SIL requiring colposcopy in HIV-positive women in Cameroon.
We enrolled, interviewed and conducted conventional cervical cytology in 282 women, aged 19–68 years, initiating antiretroviral therapy in three clinics in Cameroon. In bivariable analyses, the crude relationship between age and the presence of lesions was assessed using locally weighted regression (LOWESS) methods. In multivariate analyses, generalized linear models with prevalence as the outcome, an identity link and a binomial distribution, were used to estimate prevalence differences. Bias analyses were conducted to assess the potential effect of inaccuracies in cytology.
SIL were detected in 43.5% of the 276 women with satisfactory samples, 17.8% of whom had ASC-H/HSIL. On average, women aged 26 to 59 tended to have a slightly higher prevalence of any SIL than other women (Prevalence difference PD: 6.5%; 95%CI: -11.4, 24.4%). This PD was a function of CD4 count (heterogeneity test p-value =0.09): amongst patients with CD4 counts less than 200cells/uL, the prevalence was higher in patients aged 26–59, while there was essentially no difference amongst women with CD4 counts greater than 200 cells/uL. ASC-H/HSIL were present in women as young as 19 and as old as 62. Overall the prevalence of ASC-H/HSIL increased by 0.7% (95%CI: -3.8%, 5.1%) per decade increase in age.
Both severe and less severe lesions were prevalent at all ages suggesting little utility of age-targeted screening among HIV-positive women. Nevertheless, the long-term evolution of these lesions needs to be assessed in prospective studies.
PMCID: PMC3505154  PMID: 23106940
3.  HPV Genotypes in High Grade Cervical Lesions and Invasive Cervical Carcinoma as Detected by Two Commercial DNA Assays, North Carolina, 2001–2006 
PLoS ONE  2012;7(3):e34044.
HPV typing using formalin fixed paraffin embedded (FFPE) cervical tissue is used to evaluate HPV vaccine impact, but DNA yield and quality in FFPE specimens can negatively affect test results. This study aimed to evaluate 2 commercial assays for HPV detection and typing using FFPE cervical specimens.
Four large North Carolina pathology laboratories provided FFPE specimens from 299 women ages18 and older diagnosed with cervical disease from 2001 to 2006. For each woman, one diagnostic block was selected and unstained serial sections were prepared for DNA typing. Extracts from samples with residual lesion were used to detect and type HPV using parallel and serial testing algorithms with the Linear Array and LiPA HPV genotyping assays.
LA and LiPA concordance was 0.61 for detecting any high-risk (HR) and 0.20 for detecting any low-risk (LR) types, with significant differences in marginal proportions for HPV16, 51, 52, and any HR types. Discordant results were most often LiPA-positive, LA-negative. The parallel algorithm yielded the highest prevalence of any HPV type (95.7%). HR type prevalence was similar using parallel (93.1%) and serial (92.1%) approaches. HPV16, 33, and 52 prevalence was slightly lower using the serial algorithm, but the median number of HR types per woman (1) did not differ by algorithm. Using the serial algorithm, HPV DNA was detected in >85% of invasive and >95% of pre-invasive lesions. The most common type was HPV16, followed by 52, 18, 31, 33, and 35; HPV16/18 was detected in 56.5% of specimens. Multiple HPV types were more common in lower grade lesions.
We developed an efficient algorithm for testing and reporting results of two commercial assays for HPV detection and typing in FFPE specimens, and describe HPV type distribution in pre-invasive and invasive cervical lesions in a state-based sample prior to HPV vaccine introduction.
PMCID: PMC3315505  PMID: 22479516
4.  Diverse and High Prevalence of Human Papillomavirus Associated with a Significant High Rate of Cervical Dysplasia in Human Immunodeficiency Virus–Infected Women in Johannesburg, South Africa 
Acta cytologica  2009;53(1):10-17.
To evaluate the epidemiology of the human papillomavirus (HPV) type and correlate it with the Papanicolaou smears in human immunodeficiency virus–seropositive women in Johannesburg, South Africa.
Study Design
In a cohort of 148 women, HPV DNA testing was performed with the Roche HPV genotyping test (Branchburg, New Jersey, U.S.A.). Papanicolaou smears were performed by standard cytology utilizing 2001 Bethesda reporting guidelines.
The average age and CD4 count of the participants was 35 years and 255 cells per mm3, respectively. Fifty-four percent had abnormal Papanicolaou smears; 66% of the abnormal cytology was low grade changes, with 33% assessed as having high grade changes. HPV DNA was found in 95% of the 148 subjects assessed, with 83% having 1 or more HPV oncogenic types. Common oncogenic types were 16, 35, 53 and 18. When HPV results were stratified by CD4, there was a significant risk of an oncogenic HPV type in women with CD4 <200. Significant odds ratios for high grade lesions were seen in HPV types 16, 35, 51, 66, 69 and 73.
The results of HPV typing illustrate the diverse range of oncogenic HPV and high prevalence of oncogenic type. These results highlight the need for improved access to Papanicolaou smear screening for this population.
PMCID: PMC2922752  PMID: 19248549
cervical dysplasia; HIV; human papillomavirus type 16; uterine cervical diseases
5.  Association between cervical dysplasia and human papillomavirus in HIV seropositive women from Johannesburg South Africa 
Cancer Causes & Control   2009;21(3):433-443.
To examine the association between CD4 counts, HPV infection and the risk of cervical neoplasia among HIV-seropositive women.
A cross-sectional observational study was conducted among 1,010 HIV-seropositive women using cytology-based Pap smears. HPV DNA testing using Linear Array genotyping assay (Roche) was carried out in a subset of 191 patients. Multivariable-adjusted prevalence ratios (mPR) and 95% confidence intervals (CIs) were estimated with log-binomial regression.
Among 1,010 HIV-seropositive women, the prevalence of AGC/ASCUS, LSIL and HSIL or greater was 8.3, 23.5 and 18.0%, respectively. The risk of cervical lesions was higher with CD4 < 200 cells/mm3 vs. CD4 levels > 500/mm3. HPV types 16 (41.7%) and HPV 56 (22.2%) were the most common types in HSIL cases. Women with CD4 levels < 200/mm3 had a higher prevalence of HPV types 16 (p < 0.01) and 66 (p = 0.04). No statistical relationship between cervical lesions and HAART use was found.
The burden of HPV infection and HSIL was high and correlated with HIV-induced immunosuppression. HPV 16 was the most common type in HSIL and increased in prevalence with greater immune suppression. Prophylactic HPV 16 vaccination could prevent approximately 40% of HSIL cases. Strengthening screening programs is imperative in this population.
PMCID: PMC2835728  PMID: 19949850
Cervical dysplasia; HIV; South Africa; Human papillomavirus

Results 1-5 (5)