Ligia Peralta

Vaginal microbiome of reproductive-age women

The means by which vaginal microbiomes help prevent urogenital diseases in women and maintain health are poorly understood. To gain insight into this, the vaginal bacterial communities of 396 asymptomatic North American women who represented four ethnic groups (white, black, Hispanic, and Asian) were sampled and the species composition characterized by pyrosequencing of barcoded 16S rRNA genes. The communities clustered into five groups: four were dominated by Lactobacillus iners, L. crispatus, L. gasseri, or L. jensenii, whereas the fifth had lower proportions of lactic acid bacteria and higher proportions of strictly anaerobic organisms, indicating that a potential key ecological function, the production of lactic acid, seems to be conserved in all communities. The proportions of each community group varied among the four ethnic groups, and these differences were statistically significant [χ2(10) = 36.8, P < 0.0001]. Moreover, the vaginal pH of women in different ethnic groups also differed and was higher in Hispanic (pH 5.0 ± 0.59) and black (pH 4.7 ± 1.04) women as compared with Asian (pH 4.4 ± 0.59) and white (pH 4.2 ± 0.3) women. Phylotypes with correlated relative abundances were found in all communities, and these patterns were associated with either high or low Nugent scores, which are used as a factor for the diagnosis of bacterial vaginosis. The inherent differences within and between women in different ethnic groups strongly argues for a more refined definition of the kinds of bacterial communities normally found in healthy women and the need to appreciate differences between individuals so they can be taken into account in risk assessment and disease diagnosis.

Relationship of hormonal contraception and cervical ectopy as measured by computerized planimetry to chlamydial infection in adolescents.

Background: Adolescents are at increased risk for chlamydial infection and its sequelae. Hormonal contraception and cervical ectopy were previously suggested risk factors for chlamydia. Goal: To determine if chlamydia is more prevalent in female participants with greater ectopy and in hormonal contraceptive users. Study Design: Ninety‐seven adolescent females aged 11 to 20 years were recruited from two Baltimore inner‐city clinics. After administering a reproductive history questionnaire, endocervical specimens were tested for Chlamydia trachomatis by polymerase chain reaction. After acetic acid application to the cervix, cervical photographs were taken, the area of ectopy was quantified by computerized planimetry, and ectopy was categorized as none (0 mm2), mild (< 22 mm2), and moderate (> 22mm2). The likelihood of chlamydia by ectopy and type of hormonal contraceptive use was determined by logistic regression adjusted for age and sexual partners. Results: The odds of chlamydial infection was similar in persons with mild ectopy compared with no ectopy (adjusted odds ratio [OR], 0.76; 95% CI, 0.14‐4.03), and in persons with moderate ectopy compared with no ectopy (adjusted OR, 1.94; 95% CI, 0.40‐9.39). The likelihood of chlamydia was higher in depot‐medroxyprogesterone acetate users compared with non‐hormone users (adjusted OR, 5.44; 95% CI, 1.25‐23.6). Oral contraceptive users did not have an increased likelihood of chlamydia (adjusted OR, 0.92; 95% CI, 0.10‐8.78). Conclusion: Using a new, reliable, and standardized technique to quantify cervical ectopy, the authors did not find an elevated prevalence of chlamydial infection in adolescents with cervical ectopy. Depot‐medroxyprogesterone acetate use may increase the risk of chlamydial infection compared with combined estrogen‐progestin oral contraceptives.

Association between Trichomonas vaginalis and vaginal bacterial community composition among reproductive-age women

Objectives Some vaginal bacterial communities are thought to prevent infection by sexually transmitted organisms. Prior work demonstrated that the vaginal microbiota of reproductive-age women cluster into 5 types of bacterial communities; 4 dominated by Lactobacillus species (L. iners, L. crispatus, L. gasseri, L. jensenii) and 1 (termed community state type (CST) IV) lacking significant numbers of lactobacilli and characterized by higher proportions of Atopobium, Prevotella, Parvimonas, Sneathia, Gardnerella, Mobiluncus, and other taxa. We sought to evaluate the relationship between vaginal bacterial composition and Trichomonas vaginalis. Methods Self-collected vaginal swabs were obtained cross-sectionally from 394 women equally representing 4 ethnic/racial groups. T. vaginalis screening was performed using PCR targeting the 18S rRNA and &bgr;-tubulin genes. Vaginal bacterial composition was characterized by pyrosequencing of barcoded 16S rRNA genes. A panel of 11 microsatellite markers was used to genotype T. vaginalis. The association between vaginal microbiota and T. vaginalis was evaluated by exact logistic regression. Results T. vaginalis was detected in 2.8% of participants (11/394). Of the 11 T. vaginalis-positive cases, 8 (72%) were categorized as CST-IV, 2 (18%) as communities dominated by L. iners, and 1 (9%) as L. crispatus-dominated (P = 0.05). CST-IV microbiota were associated with an 8-fold increased odds of detecting T. vaginalis compared with women in the L. crispatus-dominated state (OR: 8.26, 95% CI: 1.07–372.65). Seven of the 11 T. vaginalis isolates were assigned to 2 genotypes. Conclusion T. vaginalis was associated with vaginal microbiota consisting of low proportions of lactobacilli and high proportions of Mycoplasma, Parvimonas, Sneathia, and other anaerobes.

Concordance of human papillomavirus in the cervix and urine among inner city adolescents.

Objectives. To evaluate concordance for human papillomaviruses (HPVs) between cervix and urine in sexually active adolescents. Methods. Cervical swabs and urine were collected from 80 adolescents in Baltimore, MD. Specimens were tested for 34 HPVs by PCR and for cancer-associated HPVs by Hybrid Capture (HC II) Probe B. Cervical vs. urine prevalence was evaluated by logistic regression with general estimating equations. Risk factors for prevalence and viral burden were evaluated by Fisher’s exact and Kruskal-Wallis tests, respectively. Results. HPV prevalence by PCR, for any HPV, was very high in the cervix (90.0%) and somewhat lower in urine (75.0%) (odds ratio, 1.07; 95% confidence interval 1.07 to 1.34). Only one adolescent was HPV-positive in urine alone. Among HPV-PCR positives at either or both sites, concordance was 82% for presence of any HPV and 40% for specific HPV types. Multiple infections were common at both sites. On an average, HC II viral burden (relative light unit ratio) was 9-fold higher in cervix than in urine (median, 47.3 vs. 4.9;P = 0.005) but correlated poorly between the two sites of the same individual (r = 0.14). Compared with normal adolescents, those with squamous intraepithelial lesions had a much higher prevalence of HPV by HC II in cervix (100%vs. 28.6, P < 0.0001) as well as in urine (86.7%vs. 35.4%, P = 0.002) and a significantly higher viral burden in the cervix (median, 141.8 vs. 7.3, P = 0.0045) but not in urine (median, 22.7 vs. 4.38;P = 0.13). Conclusion. There was a very high prevalence of HPV in cervix and urine of sexually active adolescents. Testing urine for HPV may be useful in epidemiologic investigations and in monitoring of infected women.

Prevalence of Primary HIV-1 Drug Resistance among Recently Infected Adolescents: A Multicenter Adolescent Medicine Trials Network for HIV/AIDS Interventions Study

This study examined the prevalence of primary human immunodeficiency type 1 (HIV-1) drug resistance among recently infected youth in the United States. Of the 55 subjects studied, major mutations conferring HIV drug resistance were present in 10 (18%). Eight (15%) had nonnucleoside reverse-transcriptase inhibitor (NNRTI) mutations, with the majority (6) having the K103N mutation; 2 (4%) had nucleoside reverse-transcriptase inhibitor (NRTI) mutations; and 2 (4%) had protease inhibitor (PI) mutations. Phenotypic drug resistance was present in 12 (22%) subjects: 10 (18%) for NNRTIs, 2 (4%) for NRTIs, and 3 (5.5%) for PIs. The prevalence of primary HIV-1 drug resistance, particularly to NNRTIs, in this group of recently infected youth was high.

Serologic response to hepatitis B vaccine in HIV infected and high-risk HIV uninfected adolescents in the REACH cohort

PURPOSE To evaluate hepatitis B (HBV) vaccine response rates in HIV infected and high-risk HIV uninfected youth and examine associations with responsiveness in the HIV infected group. METHODS Cohorts within the Reaching for Excellence in Adolescent Care and Health (REACH) study population were defined based on receipt of HBV vaccine both retrospectively and prospectively. Sero-responsiveness was determined by HBsAb measurements. Testing was done for HBsAg, HBsAb, and HBcAb. For HBsAb, a value of > 10 International Units per liter was considered a positive response, and the data were collected as either positive or negative from each of the reporting laboratories. Covariates of responsiveness were explored in univariate and multivariate models for each cohort. RESULTS Sixty-one subjects had received a three-dose vaccination course at the time of entry into REACH. HIV uninfected subjects had significantly higher rates of response by serology compared with HIV infected subjects (70% vs. 41.1%; chi(2) = .05; RR = .586, 95% CI: .36-.96). By the time of an annual visit 43 subjects had received three vaccinations with at least one occurring in the study period. The rates of response were similar for the HIV infected and uninfected groups (37.1% vs. 37.5%) in this cohort. Univariate and multivariate analysis in the prospective HIV infected group (N = 35) found an association between elevated CD8(+)/CD38(+)/HLA-DR(+) T cells and lack of HBV vaccine responsiveness (6.7% vs. 60%; chi(2) = .03; RR = .12, 95% CI: .02- .55). CONCLUSIONS The poor HBV vaccine response rate in the HIV uninfected high-risk adolescents was unexpected and suggests that HBV vaccination doses have not been optimized for older adolescents. This is the first report of decreased responsiveness in HIV infected subjects being associated with elevated CD8(+)/CD38(+)/HLA(-)DR(+) T cells and suggests that ongoing viral replication and concomitant immune system activation decreases the ability of the immune system in HIV infected subjects to respond to vaccination.

Histologic development of cervical ectopy: Relationship to reproductive hormones

Background and Objectives: Cervical ectopy has been proposed as a risk factor for chlamydial infection, HIV, and other sexually transmitted diseases (STDs). Ectopy is a histologic phenomenon resulting from a complex interplay of morphologic and hormonal processes. Reproductive hormones influence the production of ectopy during late fetal life, puberty, pregnancy, and with use of oral contraceptives. Ectopy is modified over time by squamous metaplasia and epitheliazation, low pH, trauma, and possibly by cervical infection. Study Design: The authors review the histologic development of ectopy from late fetal life to menopause to understand STD risk. Results: Ectopy is often assessed and quantified by direct, unaided observation during speculum examinations. This method may result in inaccurate estimates and misclassification with the transformation zone. Conclusion: Valid, reproducible measures of ectopy are necessary for epidemiologic studies to examine the impact of exogenous hormonal contraceptives on the development of ectopy and on potential infection risk.

Evaluation of self-collected vaginal swab, first void urine, and endocervical swab specimens for the detection of Chlamydia trachomatis and Neisseria gonorrhoeae in adolescent females.

OBJECTIVE To assess the concordance of self-obtained vaginal swabs (SVS), first void urine samples (FVU) and provider-collected endocervical swabs (PES) for the detection of Chlamydia trachomatis (CT) and Neisseria gonorrhea (NG) in adolescents. METHODS A total of 342 adolescent women and 1080 baseline and semi-annual visits were analyzed. FVU, SVS and PES were collected at each biannual visit. All specimens were tested by BDProbeTec ET(trade mark) Amplified DNA Assay. Sensitivity, specificity, positive predictive value (PPV) negative predictive value (NPV) and kappa coefficient were calculated to evaluate the ability to identify possible infected cases using samples from three anatomic sites and the test agreement between any two of these three specimen types. Positive results from at least two of the three specimens collected from same subject at the same study visit was considered true positive. RESULTS The positivity rates for CT and NG were 26.6 and 11.7 per 100 women respectively. The sensitivities of SVS, FVU and PES for detecting CT were 97.3%, 89.2% and 90.1% respectively. For the detection of NG, the sensitivities of the three sampling methods were 100%, 88.6% and 95.5% respectively. The specificities were between 94.7% and 99.7% for both CT and NG. Kappa coefficients of CT test results were 0.89, 0.88 and 0.83 for specimen pairs SVSvsPES, SVSvsFVU and PESvsFVU respectively. For the detection of NG, kappa coefficients were 0.91, 0.87 and 0.91 for these three pairs (all P<0.0001). Kappa>0.75 is considered excellent agreement between specimens. CONCLUSION There were strong agreements among SVS, PES and FVU specimens on the detection of CT and NG infections in adolescent females using nucleic acid amplification test. SVS represented as high as or more sensitive an approach for detecting both CT and NG compared to PES. Although FVU was the least sensitive sampling method, it is also the least invasive method. Thus SVS and FVU may provide a reliable alternative to endocervical specimens for CT and NG screening.

Contraceptive choices in HIV infected and HIV at-risk adolescent females

PURPOSE To describe reported contraception use in HIV infected and HIV uninfected but at-risk female adolescents, and determine associations with the reported consistent use of effective contraception methods, including its association with pregnancy. METHODS HIV infected and at-risk female youth, aged 13-18 years, who were sexually active and reporting no intention to become pregnant, were included. Contraception use data from three consecutive visits (approximately 6 months apart) were used. RESULTS Ninety-four percent of HIV infected and 89% of at-risk subjects reported choosing a main contraception method with demonstrated efficacy when used consistently. Approximately 50% chose partner condoms. HIV infected youth were more likely to report 100% partner condom use in the past 3 months (73% vs. 46%; OR 3.3; 95% CI: 1.7-5.6). At-risk youth were 2.5 times more likely than HIV infected subjects to report using nothing (95% CI: 1.1-5.8). Slightly more than half (56%) demonstrated the consistent reporting of effective methods (CREM) of contraception. In multivariate analysis, HIV infection (OR 4.0; 95% CI: 2.2-8.2) and African-American race (OR 2.7; 95% CI: 1.1-6.6) were significantly associated with CREM. Subjects reporting inconsistent or unreliable contraception use had higher 1-year pregnancy rates than CREM subjects (32% vs. 14%; p = .002). CONCLUSIONS Only half of HIV infected and at-risk youth reported using effective contraception consistently, despite its availability. Additionally, regardless of reported contraceptive use, the rates of unplanned pregnancy were unacceptably high.

Cervical ectopy and the transformation zone measured by computerized planimetry in adolescents

Objective: To determine whether cervical ectopy and the transformation (T) zone were larger in adolescents using oral contraceptives (OCs) compared to depot medroxyprogesterone acetate (DMPA). Method: Cervical photographs were taken on 91 adolescents in Baltimore, Maryland. Ectopy and T zone size were measured using computerized planimetry. Patients provided reproductive and sexual history. Correlates of ectopy and T zone size were identified by proportional odds and linear regression models, respectively. Result: Twenty‐five women had no ectopy. Parity was independently associated with greater ectopy (OR 3.9, 95% CI 1.37–11.11). Predictors of smaller ectopy were douching (OR 0.23, 95% CI 0.09–0.65), and shorter sexual history (OR 0.20, 95% CI 0.05–0.74). Neither OC or DMPA were associated with ectopy. Predictors of greater T zone size were years since menarche (13.8 mm2/year, P=0.003) and OCs (54.7 mm2, P=0.05). DMPA predicted a smaller T zone (−67.0 mm2, P=0.01). Conclusion: Computerized planimetry provides standardized measurements. Douching and sexual activity may decrease ectopy through increased squamous metaplasia. Hormonal contraceptives were not associated with ectopy in adolescents. However, long‐term progestin use may decrease T zone size.