No abstract

This cohort study of 182 women attending a sexually transmitted disease clinic evaluated the hypothesis that women colonized by lactobacilli have decreased acquisition of vaginal infections. During a 2-year follow-up, 50 women acquired bacterial vaginosis (BV), 25 acquired symptomatic vulvovaginal candidiasis (VVC), and 7 acquired vaginal trichomoniasis. By multivariate analysis, utilizing Cox proportional hazards modeling with time-dependent covariates, acquisition of BV was independently associated with lack of vaginal H2O2-producing lactobacilli (hazard ratio [HR] = 4.0, P < .001) or presence of only non-H2O2-producing lactobacilli (HR = 2.2, P = .02). Acquisition of BV was associated with having a new sex partner (HR = 2.5, P = .004) and with douching for hygiene (HR = 2.1, P = .05). Absence of lactobacilli did not increase acquisition of VVC. Trichomoniasis was associated only with having a new sex partner (HR = 4.7, P = .05). These results support the hypothesis that H2O2-producing vaginal lactobacilli protect against acquisition of BV but do not protect against VVC or vaginal trichomoniasis.

Cervical intraepithelial neoplasia is a common and apparently early manifestation of cervical infection by HPV, particularly types 16 and 18.

Many cases of mucopurulent cervicitis (MPC) are idiopathic and cannot be attributed to the known cervical pathogens Neisseria gonorrhoeae, Chlamydia trachomatis, or herpes simplex virus. Because Mycoplasma genitalium is associated with nongonoccocal urethritis in men, its role in MPC, the corresponding syndrome in women, was investigated. Archived cervical specimens from women recruited in the Harborview Sexually Transmitted Disease Clinic in Seattle from 1984 to 1986 were tested, using polymerase chain reaction, in a study that identified other causes of and risk factors for MPC. M. genitalium was detected in 50 (7.0%) of 719 women. Young age, multiple recent partners, prior miscarriage, smoking, menstrual cycle, and douching were positively associated with M. genitalium, whereas bacterial vaginosis and cunnilingus were negatively associated. After adjustment for age, phase of menstrual cycle, and presence of known cervical pathogens, women with M. genitalium had a 3.3-fold greater risk (95% confidence interval, 1.7-6.4) of MPC, which suggests that this organism may be a cause of MPC.

Typically during human immunodeficiency virus type 1 (HIV-1) infection, a nearly homogeneous viral population first emerges and then diversifies over time due to selective forces that are poorly understood. To identify these forces, we conducted an intensive longitudinal study of viral genetic changes and T-cell immunity in one subject at <17 time points during his first 3 years of infection, and in his infecting partner near the time of transmission. Autologous peptides covering amino acid sites inferred to be under positive selection were powerful for identifying HIV-1-specific cytotoxic-T-lymphocyte (CTL) epitopes. Positive selection and mutations resulting in escape from CTLs occurred across the viral proteome. We detected 25 CTL epitopes, including 14 previously unreported. Seven new epitopes mapped to the viral Env protein, emphasizing Env as a major target of CTLs. One-third of the selected sites were associated with epitopic mutational escapes from CTLs. Most of these resulted from replacement with amino acids found at low database frequency. Another one-third represented acquisition of amino acids found at high database frequency, suggesting potential reversions of CTL epitopic sites recognized by the immune system of the transmitting partner and mutation toward improved viral fitness in the absence of immune targeting within the recipient. A majority of the remaining selected sites occurred in the envelope protein and may have been subjected to humoral immune selection. Hence, a majority of the amino acids undergoing selection in this subject appeared to result from fitness-balanced CTL selection, confirming CTLs as a dominant selective force in HIV-1 infection.