Trichomonas vaginalis (TV) and bacterial vaginosis (BV) are both common infections found among human immunodeficiency virus (HIV)-positive women, with respective prevalence rates in this population ranging from 11% to 30%1–6 and 35% to 55%.1,6–9 Both conditions have been separately associated with HIV acquisition10–13 and increased genital shedding,14–18 which may enhance sexual and perinatal transmission of HIV. Also, both TV and BV have high recurrence rates that indicate the complexity of successfully treating each condition.19,20 Studies among mostly HIV-negative women have shown a strong association between TV and BV, which imply that the 2 frequently occur together,21–28 but this relationship has not been well studied among HIV-positive women.
The co-occurrence of TV and BV suggests that one of these conditions may alter a woman's susceptibility to the other. A prospective study found that abnormal vaginal flora was associated with an increased risk of acquiring TV, suggesting that BV may increase a woman's susceptibility to TV infection.21 Conversely, a cross-sectional study found a constant prevalence of TV in women with Nugent scores ≥4 and demonstrated a nonlinear association between TV and abnormal vaginal flora.29 The nonlinear relationship suggests that infection with TV may create an environment that favors the development of BV. Otherwise, one would expect to see a gradual increase in the prevalence of TV as vaginal flora deviation from normal increased.
The purpose of this study was to examine the cross-sectional relationship between TV and abnormal vaginal flora among a group of HIV-positive women in the United States, and to examine factors associated with the presence of BV among HIV-positive women with TV infection.
HIV-positive women were recruited from the HIV Outpatient Program in New Orleans, LA, between June 2002 and January 2005 to participate in a cross-sectional screening study to investigate multiple issues surrounding sexually transmitted diseases. Women with the following criteria were eligible: age ≥18 years, scheduled to undergo a gynecological examination, and provide informed consent. Data and specimen collection methods have been previously published.14
In brief, clinical information collected for the study included the following laboratory diagnosis: TV by InPouch culture (Biomed Diagnostics; White City, OR), BV by Gram stain, Neisseria gonorrhea, and Chlamydia trachomatis using the ProbeTec strand displacement DNA amplification method (Becton Dickinson, Sparks, MD), and vulvovaginal candidiasis by culture. Gram stains were scored using Nugent et al criteria30 with scores of 0 to 3 considered normal, 4 to 6 intermediate, and ≥7 BV. We defined abnormal vaginal flora as Nugent scores ≥4. Genital odor, vaginal discharge, vaginal petechiae, and erythema were observed by the clinical provider. The provider also performed wet mount microscopy.
Respondents were interviewed using computer-assisted self-administered interviews or computer-assisted personal interviews, depending on the woman's preference. Interviews were conducted either before or after the clinical examination, depending on the clinic flow, and captured sociodemographic and behavioral characteristics of the women.
The prevalence rates were calculated from participants in the screening study using those with complete testing data as the denominator for each diagnosis. TV-positive rates were examined across categories of Nugent scores, and odds ratios were calculated to measure the association. The analysis was then limited to HIV+/TV+ women, and the rate of BV was determined. Baseline associations between BV status and selected clinical and behavioral characteristics were examined using χ2 or Fisher exact test as appropriate. All analyses were conducted using SAS version 9.1 (SAS Institute, Cary, NC).
A total of 397 HIV-positive women were screened, with more than half of the women (57.9%, n = 230) on antiretroviral therapy. There was demographic data available for 377 women, with a mean age of 36.4 years (±9.2). A majority were black (84.4%, n = 318) and not married/cohabitating (81.7%, n = 308). In the last 4 weeks, 66.3% of the women had at least 1 male sex partner (n = 250).
The prevalence rates were as follows: 28.0% for TV (106/378), 51.4% for BV (196/381), 64.8% for abnormal vaginal flora (247/381), 17.5% for TV/BV coinfection (64/365), and 23.0% for the combination of TV/abnormal vaginal flora (84/365). There was a significant association between TV and BV (61.0% of TV+ women had BV vs. 47.3% of TV− women; P = 0.02) and a strong association between TV and abnormal vaginal flora (80.0% of TV+ women had abnormal vaginal flora vs. 58.9% of TV− women; P = 0.0001). The prevalence rates for other infections were as follows: 3.4% for C. trachomatis (13/387), 0.8% for N. gonorrhea (3/387), and 28.4% for candidiasis (110/387).
The distribution of TV infection by vaginal flora was examined (Table 1). There was a significant difference in the prevalence of TV among women with normal vaginal flora (16.4%) versus women with intermediate flora (40.0%, P = 0.0008). The prevalence of TV among women with intermediate flora and women with BV was similar (40.0% vs. 34.2%; P = 0.45).
The analysis was then limited to HIV-positive women with TV infection. Of the HIV+/TV+ women with complete Gram stain results (n = 105), demographic and behavioral information was available on 101 participants with a median age of 35 years (range, 18–54). The majority of these women were black (93.1%, n = 94), not married or cohabitating (83.2%, n = 84), unemployed (82.2%, n = 83), and had a high school education or less (79.2%, n = 80). Most women reported douching (79.2%, n = 80), using a condom at last vaginal intercourse (67.3%, n = 68), and having at least one male sex partner in the last 4 weeks (74.3%, n = 75).
Approximately half of the HIV+/TV+ women were on antiretroviral therapy (51.4%, n = 54). Per the provider assessment, 16.2% of the women had unusual genital odor (n = 17), 13.3% had vaginal erythema (n = 14), 5.7% had vaginal petechiae (n = 6), and 57.1% had moderate to copious amounts of vaginal discharge (n = 60). Of 102 women with information from wet mount preparations, 31.4% had a positive whiff test (n = 32) defined as amine or fishy odor after KOH was added to the wet preparation, and 21.6% had clue cells present (n = 22). In total, 61.0% of the HIV+/TV+ women also had BV (n = 64).
Table 2 presents baseline characteristics of the HIV+/TV+ women by BV status. Women with BV were more likely to have one or more male sex partners in the last 4 weeks (P = 0.001) and to have one or more alcoholic drinks in an average week (P = 0.005) compared to the women without BV. From the provider assessment, HIV+/TV+ women with BV were more likely to have unusual genital odor (P = 0.05), abnormal consistency of vaginal discharge (P = 0.03), abnormal color of vaginal discharge (P = 0.03), positive whiff test (0.002), and clue cells present on wet preparation (P = 0.02). The women with BV were also more likely to douche (P = 0.18) and less likely to have used a condom at last vaginal sex (P = 0.18), but not at significant levels. There were no differences found by BV status about other infections, specifically chlamydia, gonorrhea, and candidiasis.
To our knowledge, this is the first prevalence study of TV/BV coinfection among HIV-positive women in the United States. The prevalence of TV/BV coinfection was high at 17.5%. A majority of HIV-positive women with TV also had BV (61.0%). If the presence of TV infection creates an environment that favors the development of BV, the expectation would be that BV is more frequent among women with TV infection.26 In our group of HIV-positive women, a significantly higher prevalence of BV was found among women with TV infection compared with TV-negative women. We also examined the presence of abnormal vaginal flora and found a significantly higher prevalence of abnormal vaginal flora among women with TV infection compared with TV-negative women.
The association between TV and gradations of vaginal flora was not linear. TV prevalence increased sharply between HIV-positive women with normal flora and those with intermediate flora; however, the prevalence of TV remained the same for women with intermediate flora and BV. Our findings are consistent with the findings of Moodley et al that showed a nonlinear relationship between TV prevalence and vaginal flora among African HIV-positive and -negative women.29 The similar prevalence of TV in women with abnormal vaginal flora (intermediate and BV Nugent scores) supports the notion that TV infection may create an environment that is conducive to a shift away from normal flora, and therefore, may be a factor in the development of BV. Our study design was cross-sectional, and future prospective, longitudinal studies are needed to examine the relationship between TV and BV using methods to establish temporality. The magnitude of this frequent combination has implications for worldwide HIV prevention and control strategies.
For health care providers of HIV-positive women, the high rate of BV that accompanies TV infection has implications for treatment decisions. The Centers for Disease Control and Prevention no longer recommends the metronidazole 2 g oral single dose for treatment of BV, yet this treatment regimen is still recommended for TV infection31 and may result in women being undertreated if they have both TV and BV. Also, if the combined presence of TV and BV has a synergistic effect on genital shedding of HIV, adequate treatment for both conditions would be paramount.
In our study, the HIV-positive women with TV and BV had more clinical signs compared to the women with TV only, including higher rates of unusual genital odor, abnormal consistency and color of vaginal discharge, positive whiff tests, and presence of clue cells. However, these clinical signs alone would not have identified many of the cases of BV. The sensitivity of Amsel et al criteria32 compared to Nugent score for the diagnosis of BV among HIV-positive women is only 34% to 37%,1,33 and therefore, BV diagnosis will frequently be missed at the point of care.
One or more recent sex partners and weekly alcohol use were positively associated with BV among our group of HIV-positive women with TV infection. Alcohol use has been previously associated with BV6,34–36 in groups of HIV-positive and -negative women, and the association between BV and sexual contact has been well established.37
In conclusion, health care providers for HIV-positive women should be aware of the high prevalence of TV/BV coinfection in this population, as well as the high rate of BV among HIV-positive women with TV infection. Given these results, research is needed to examine potential interactive effects of these 2 conditions on the clinical course and treatment of both in HIV-positive women.
1.Kissinger PJ, Dumestre J, Clark RA, et al. Vaginal swabs versus lavage for detection of Trichomonas vaginalis
and bacterial vaginosis among HIV-positive women. Sex Transm Dis 2005; 32:227–230.
2.Sorvillo F, Kovacs A, Kerndt P, et al. Risk factors for trichomoniasis among women with human immunodeficiency virus (HIV) infection at a public clinic in Los Angeles County, California: Implications for HIV prevention. Am J Trop Med Hyg 1998; 58:495–500.
3.Seth P, Wingood GM, Diclemente RJ. Exposure to alcohol problems and its association with sexual behaviour and biologically confirmed Trichomonas vaginalis
among women living with HIV. Sex Transm Infect 2008; 84:390–392.
4.Magnus M, Clark R, Myers L, et al. Trichomonas vaginalis
among HIV-infected women: Are immune status or protease inhibitor use associated with subsequent T. vaginalis
positivity? Sex Transm Dis 2003; 30:839–843.
5.Bersoff-Matcha SJ, Horgan MM, Fraser VJ, et al. Sexually transmitted disease acquisition among women infected with human immunodeficiency virus type 1. J Infect Dis 1998; 178:1174–1177.
6.Cu-Uvin S, Hogan JW, Warren D, et al; HIV Epidemiology Research Study Group. Prevalence of lower genital tract infections among human immunodeficiency virus (HIV)-seropositive and high-risk HIV-seronegative women. Clin Infect Dis 1999; 29:1145–1150.
7.Watts DH, Springer G, Minkoff H, et al. The occurrence of vaginal infections among HIV-infected and high-risk HIV-uninfected women: Longitudinal findings of the women's interagency HIV study. J Acquir Immune Defic Syndr 2006; 43:161–168.
8.Warren D, Klein RS, Sobel J, et al. A multicenter study of bacterial vaginosis in women with or at risk for human immunodeficiency virus infection. Infect Dis Obstet Gynecol 2001; 9:133–141.
9.Clark RA, Theall KP, Amedee AM, et al. Frequent douching and clinical outcomes among HIV-infected women. Sex Transm Dis 2007; 34:985–990.
10.Van Der Pol B, Kwok C, Pierre-Louis B, et al. Trichomonas vaginalis
infection and human immunodeficiency virus acquisition in African women. J Infect Dis 2008; 197:548–554.
11.McClelland RS, Sangare L, Hassan WM, et al. Infection with Trichomonas vaginalis
increases the risk of HIV-1 acquisition. J Infect Dis 2007; 195:698–702.
12.Sewankambo N, Gray RH, Wawer MJ, et al. HIV-1 infection associated with abnormal vaginal flora morphology and bacterial vaginosis. Lancet 1997; 350:546–550.
13.Atashili J, Poole C, Ndumbe PM, et al. Bacterial vaginosis and HIV acquisition: A meta-analysis of published studies. AIDS 2008; 22:1493–1501.
14.Kissinger P, Amedee A, Clark RA, et al. Trichomonas vaginalis
treatment reduces vaginal HIV-1 shedding. Sex Transm Dis 2009; 36:11–16.
15.Wang CC, McClelland RS, Reilly M, et al. The effect of treatment of vaginal infections on shedding of human immunodeficiency virus type 1. J Infect Dis 2001; 183:1017–1022.
16.Coleman JS, Hitti J, Bukusi EA, et al. Infectious correlates of HIV-1 shedding in the female upper and lower genital tracts. AIDS 2007; 21:755–759.
17.Sha BE, Zariffard MR, Wang QJ, et al. Female genital-tract HIV load correlates inversely with Lactobacillus
species but positively with bacterial vaginosis and Mycoplasma hominis
. J Infect Dis 2005; 191:25–32.
18.Cu-Uvin S, Hogan JW, Caliendo AM, et al. Association between bacterial vaginosis and expression of human immunodeficiency virus type 1 RNA in the female genital tract. Clin Infect Dis 2001; 33:894–896.
19.Kissinger P, Secor WE, Leichliter JS, et al. Early repeated infections with Trichomonas vaginalis
among HIV-positive and HIV-negative women. Clin Infect Dis 2008; 46:994–999.
20.Hay P. Recurrent bacterial vaginosis. Curr Opin Infect Dis 2009; 22:82–86.
21.Martin HL, Richardson BA, Nyange PM, et al. Vaginal lactobacilli, microbial flora, and risk of human immunodeficiency virus type 1 and sexually transmitted disease acquisition. J Infect Dis 1999; 180:1863–1868.
22.Schwebke JR, Desmond R. A randomized trial of metronidazole in asymptomatic bacterial vaginosis to prevent the acquisition of sexually transmitted diseases. Am J Obstet Gynecol 2007; 196:517.e1–517.e6.
23.Thomason JL, Gelbart SM, Sobun JF, et al. Comparison of four methods to detect Trichomonas vaginalis
. J Clin Microbiol 1988; 26:1869–1870.
24.Franklin TL, Monif GR. Trichomonas vaginalis
and bacterial vaginosis. Coexistence in vaginal wet mount preparations from pregnant women. J Reprod Med 2000; 45:131–134.
25.Demirezen S, Korkmaz E, Beksac MS. Association between trichomoniasis and bacterial vaginosis: examination of 600 cervicovaginal smears. Cent Eur J Public Health 2005; 13: 96–98.
26.Heller DS, Maslyak S, Skurnick J. Is the presence of Trichomonas
on a Pap smear associated with an increased incidence of bacterial vaginosis? J Low Genit Tract Dis 2006; 10:137–139.
27.Madhivanan P, Bartman MT, Pasutti L, et al. Prevalence of Trichomonas vaginalis
infection among young reproductive age women in India: Implications for treatment and prevention. Sex Health 2009; 6:339–344.
28.Rugpao S, Sriplienchan S, Rungruengthanakit K, et al. Risk factors for bacterial vaginosis incidence in young adult Thai women. Sex Transm Dis 2008; 35:643–648.
29.Moodley P, Connolly C, Sturm AW. Interrelationships among human immunodeficiency virus type 1 infection, bacterial vaginosis, trichomoniasis, and the presence of yeasts. J Infect Dis 2002; 185:69–73.
30.Nugent RP, Krohn MA, Hillier SL. Reliability of diagnosing bacterial vaginosis is improved by a standardized method of gram stain interpretation. J Clin Microbiol 1991; 29:297–301.
31.CDC. Sex transmitted diseases treatment guidelines, 2006. MMWR 2006; 55:RR-11.
32.Amsel R, Totten PA, Spiegel CA, et al. Nonspecific vaginitis. Diagnostic criteria and microbial and epidemiologic associations. Am J Med 1983; 74:14–22.
33.Sha BE, Chen HY, Wang QJ, et al. Utility of Amsel criteria, Nugent score, and quantitative PCR for Gardnerella vaginalis
, Mycoplasma hominis
, and Lactobacillus
spp. for diagnosis of bacterial vaginosis in human immunodeficiency virus-infected women. J Clin Microbiol 2005; 43:4607–4612.
34.Baisley K, Changalucha J, Weiss HA, et al. Bacterial vaginosis in female facility workers in north-western Tanzania: Prevalence and risk factors. Sex Transm Infect 2009; 85:370–375.
35.Thorsen P, Vogel I, Molsted K, et al. Risk factors for bacterial vaginosis in pregnancy: A population-based study on Danish women. Acta Obstet Gynecol Scand 2006; 85:906–911.
36.Fonck K, Kaul R, Keli F, et al. Sexually transmitted infections and vaginal douching in a population of female sex workers in Nairobi, Kenya. Sex Transm Infect 2001; 77:271–275.
37.Fethers KA, Fairley CK, Hocking JS, et al. Sexual risk factors and bacterial vaginosis: A systematic review and meta-analysis. Clin Infect Dis 2008; 47:1426–1435.