Detection of Trichomonas vaginalis in pregnant women with the InPouch TV culture system

Molecular diagnosis of Trichomonas vaginalis in liquid-based Papanicolaou samples in Shiraz, southern Iran

BACKGROUND

Trichomoniasis is a parasitic infection of the urinary and genital tract, caused by Trichomonas vaginalis. This study aimed to investigate the molecular diagnosis of T. vaginalis infection in liquid-based Papanicolaou samples in Shiraz, southern Iran.

MATERIALS AND METHODS

In this cross-sectional study, 534 liquid-based Papanicolaou samples were collected from women referring to the laboratory of Motahari Clinic of Shiraz University of Medical Sciences in 2021. Genomic DNA were extracted from the samples and examined for evidence of T. vaginalis using polymerase chain reaction (PCR) using TVK3 and TVK7 specific primers.

RESULTS

The mean age of participants was 39.28 ± 9.89 with a maximum age of 65 and a minimum age of 19 years. T. vaginalis DNA fragments were detected in 4.86% (26/534) of the cases. There was significantly higher prevalence in the age groups of 21 to 30 and 41 to 50 years (46.15%, p = 0.001 and 38.46%, p = 0.015, respectively). Furthermore, the results showed an association between a history of foamy discharge and Trichomonas positivity (p = 0.001).

CONCLUSION

T. vaginalis infection is common in liquid-based Papanicolaou samples of women who attended regular health check-ups in the study area. Screening for trichomoniasis in populations, particularly if using highly sensitive methods such as PCR, may lead to increased detection and treatment.

PCR Detection and Sequencing of Trichomonas vaginalis in Women with Suspected Vaginitis in Southwestern Iran

INTRODUCTION

The human being is considered a natural host for Trichomonas vaginalis (T. vaginalis), which causes trichomoniasis, the most frequent non-viral sexually transmitted infectious disease in the world. The current study aimed to evaluate the prevalence and sequencing of T. vaginalis in women with vaginitis. ; Methods: In the current research, 514 vaginal discharge samples were obtained from women with vaginitis. The specimens were evaluated by the direct wet mount examination, Dorset culture medium, and PCR technique. Primers were designed for the detection of TVK3/TVK7, TVA5/TVA6 genes specific for the identification of T. vaginalis. The PCR-positive samples were sequenced and compared with the sequences registered in the GenBank database. ; Results: Among the collected samples, 30 (5.83%), 45 (8.75%), 90 (17.50%), and 62 (12.06%) cases were positive for T. vaginalis when assayed by the direct wet mount examination, Dorset culture medium, and PCR technique (TVK3/TVK7, TVA5/TVA6 genes), respectively. There was no significant relationship between trichomoniasis and demographic characteristics of women, such as age, occupational status, mode of delivery, number of deliveries, educational level, and contraceptive methods (p˃0.05). The range of vaginal pH was between 5-7 in women with vaginitis, and there was a significant statistical correlation between the pH values and the infection rate (p<0.05). The PCR-positive samples had 100% sequence homology with the reference sequence in the GenBank database (accession number L23861.1). ; Conclusion: This study confirmed a relatively high prevalence of T. vaginalis in the southwestern region of Iran. According to our results, the PCR method, especially detecting TVK3/TVK7 genes, was more sensitive than the direct wet mount examination and Dorset culture medium methods.

Update on the Diagnosis of Sexually Transmitted Infections

Sexually transmitted infections (STIs) are one of the most frequent and universal Public Health problems. Health professionals should be aware of the possibility of STIs due to their high morbidity and the presence of sequelae. The delay in the diagnosis is one of the factors that justifies the difficulty to infections control. Diagnostic tests allow the introduction of aetiological treatment and also lead to treating symptomatic and asymptomatic patients more effectively, as well as to interrupt the epidemiological transmission chain without delay. In this review we have made an update of the main existing diagnostic methods for the more important STIs.

Prevalence, clinical features, and diagnosis of Trichomonas vaginalis among female STI clinic attendees in Trinidad

Background

Trichomonas vaginalis (TV) is one of the most common pathogens causing sexually transmitted infections (STIs) in both men and women. Since there are no accurate prevalence data available on TV infection among women for Trinidad and Tobago and in the Caribbean region, there is a great need for research to study the dynamics of the infection and its transmission.

Objectives

To determine the prevalence and diagnose TV infection in women attending the STI clinic and to provide recommendations for control and prevention of trichomoniasis in the community.

Study Design

A cross-sectional study was designed after obtaining the informed consent. Following a routine clinical examination, vaginal swabs were collected - one for wet mount preparation, one for InPouch culture, and other two for OSOM rapid test/and fluorescent antibody testing. Cotton swabs and Dacron swabs were used for testing.

Results

A prevalence of 16% of trichomoniasis out of 422 females was recorded. In all, 65 (65%) were in the age range of 15-29 years and peak of 30% in the age group of 20-24 years. Vaginal discharge was a common complaint (83%); 75.6% had foul odor and only 9.8% had typical fishy odor. The majority of them (87%) had whitish-yellow colored discharge.

Conclusion

Prevalence of trichomoniasis is significant in the female population attending STI clinic. Targeting high-risk age group between 15 and 29 years for control and prevention would be beneficial. Prompt and accurate diagnosis using appropriate laboratory test is recommended.

Trichomonas vaginalis: Clinical relevance, pathogenicity and diagnosis

Trichomonas vaginalis is the etiological agent of trichomoniasis, the most prevalent non-viral sexually transmitted disease worldwide. Trichomoniasis is a widespread, global health concern and occurring at an increasing rate. Infections of the female genital tract can cause a range of symptoms, including vaginitis and cervicitis, while infections in males are generally asymptomatic. The relatively mild symptoms, and lack of evidence for any serious sequelae, have historically led to this disease being under diagnosed, and under researched. However, growing evidence that T. vaginalis infection is associated with other disease states with high morbidity in both men and women has increased the efforts to diagnose and treat patients harboring this parasite. The pathology of trichomoniasis results from damage to the host epithelia, caused by a variety of processes during infection and recent work has highlighted the complex interactions between the parasite and host, commensal microbiome and accompanying symbionts. The commercial release of a number of nucleic acid amplification tests (NAATs) has added to the available diagnostic options. Immunoassay based Point of Care testing is currently available, and a recent initial evaluation of a NAAT Point of Care system has given promising results, which would enable testing and treatment in a single visit.

Diagnosis of Trichomonas Vaginalis from Vaginal Specimens by Wet Mount Microscopy, In Pouch TV Culture System, and PCR

Background:

In recent years, trichomoniasis has emerged as the most common sexually transmitted disease and limited data are available on the effective screening technique for the diagnosis of Trichomonas vaginalis.

Aim

The aim was to compare and evaluate different diagnostic methods like wet mount microscopy, In Pouch TV culture, and Polymerase chain reaction (PCR) to establish which method or combination of methods was most effective for detection of Trichomonas vaginalis in vaginal swab specimens.

Settings and Design:

This is a cross-sectional study.

Materials and Methods:

A total of 200 patients complaining of vaginal discharge were included in the study. Three vaginal swabs were screened for trichomoniasis by wet mount microscopy, In Pouch TV culture system and PCR, using TVK3 and TVK7 specific primers.

Results

Of the 200 cases studied, 36 (18%) were positive by wet mount microscopy, 44 (22%) by In Pouch TV culture system and 60(30%) by PCR. Sensitivity and specificity of wet mount were 60% and 100%, respectively, whereas sensitivity and specificity of the In Pouch TV culture system were 73.33% and 100%, respectively when compared to PCR.

Conclusion

Comparison of different methods showed that at least two techniques, such as wet mount microscopy and culture have a better chance of detection of T. vaginalis infection. Diagnosis of trichomoniasis by PCR was found to be highly specific and sensitive, but its availability and cost effectiveness limit its use in routine diagnostic laboratories.

Performance of rapid immunochromatographic assay in the diagnosis of Trichomoniasis vaginalis

Trichomonas vaginalis accounts for nearly half of all curable sexually transmitted diseases worldwide with serious health consequences. Effort to increase the sensitivity of its diagnosis is critical to both control measures and epidemiologic studies. This study was conducted to evaluate the OSOM® Trichomonas Rapid Test (Sekisui Diagnostics, Framingham, MA, USA), a qualitative antigen-detection immunochromatographic (IC) assay in the diagnosis of vaginal trichomoniasis comparable to the conventional methods. The study enrolled 258 females aged 18-50 years classified into symptomatic (185) and asymptomatic (73) groups. Vaginal swab specimens were obtained for wet mount, stained preparation (Giemsa, acridine-orange), culture (InPouch TV™, modified Diamond's), and for rapid OSOM testing. Trichomonas vaginalis was detected in 67, 66, 71, 99, 96, and 97 using wet mount, acridine-orange stain, Giemsa stain, modified Diamond's, InPouch media, and OSOM test, respectively. In comparison to a composite reference standard (CRS) of wet mount microscopy and culture, OSOM test reported 97.98%, 99.37%, 98.98%, 98.75%, and 98.84% for sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy, respectively. The OSOM test proved to be a simple and objective test. This rapid point-of-care-test will contribute significantly in the diagnosis of vaginal trichomoniasis and will increase the understanding of its still vague epidemiology.

Tinidazole vs metronidazole for the treatment of bacterial vaginosis

OBJECTIVE

The purpose of this study was to compare the efficacy of 2 different doses of tinidazole with metronidazole for the treatment of bacterial vaginosis and to compare the side effects of the drugs.

STUDY DESIGN

Women were assigned randomly to receive metronidazole 500 mg twice daily, tinidazole 500 mg twice daily, or tinidazole 1 g twice, all for 7 days. Follow-up visits were conducted at days 14 and 28.

RESULTS

Five hundred ninety-three women were enrolled. There were no significant differences between the treatment arms. Overall cure rates were 76.8% at 14 days and 64.5% at 1 month. Women who admitted to engaging in sexual intercourse during the study were significantly more likely to have bacterial vaginosis at the follow-up visit. There were no significant differences in adverse events across treatment arms.

CONCLUSION

There were no differences in cure rates between metronidazole and either of the tinidazole dosing regimens that were studied. In addition, there were no important differences in the side-effect profiles of metronidazole and tinidazole.

Molecular diagnosis of trichomoniasis in negative samples examined by direct smear and culture

BACKGROUND

Trichomoniasis is an extremely common sexually transmitted infection (STI) worldwide and is associated with important public health problems, including amplification of HIV transmission. This disease is in forms of symptomatic and asymptomatic in women and may depend on host as well as parasite variables. Most of the studies reported from females are based on examination of vaginal secretions and urine samples by direct smear and culture in modified Diamond's media. The aim of this study was checking the samples, which were negative by direct smear and culture, with PCR technique.

METHODS

The urine samples and vaginal discharge of patients attending Gynecology Clinics of Mazandaran Province, Iran with different symptoms rechecked for Trichomonas vaginalis by PCR technique using primers targeting a conserved region of the beta-tubulin genes of the parasite. Data were analyzed by Epi Info software program

RESULTS

Out of 161 negative samples by direct smear and culture, seven samples (4.3%) were positive by PCR technique.

CONCLUSION

Diagnosis of trichomoniasis by PCR is a sensitive and specific method that could play important role to help the physicians for properly treatment and control of infection.

Correlates of trichomonas prevalence among street-recruited, drug-using women enrolled in a randomized trial

OBJECTIVES

Substance-using women need prevention technologies and programs to reduce risk of HIV/sexually transmitted infection (STI). We examined STI prevalence and identified risk correlates for female drug users.

METHODS

We used interviewer-administered and computer-assisted surveys, and tested specimens for four, treatable STIs (trichomonas, early syphilis, gonorrhea, chlamydia) on 198 HIV-seronegative, street-recruited, substance-using women enrolled in a randomized trial to reduce HIV/STI risk.

RESULTS

Most women were crack users (88%), reported sex exchange (80%) and were not in drug user treatment (74%). Two-thirds were African-American and nearly all were unemployed. Protection during sex was infrequent. African-American women reported fewer unprotected sex acts and fewer sexual partners, but greater crack use and more sex-for exchange, than whites or Hispanics. Trichomonas prevalence (36.9%) exceeded that for chlamydia (3.5%), syphilis (1.5%), and gonorrhea (0%). In multivariate logistic regression, having a primary and casual partner more than doubled (AOR 2.86) the risk of having trichomonas and being African-American raised the risk by more than 8 times (AOR 8.45).

CONCLUSIONS

African-American, drug-using women, and women with multiple partner types, are in urgent need of effective STI/HIV prevention interventions.

Trichomonas vaginalis: diagnosis and clinical characteristics in pregnancy

Objective: The objectives of this study were to 1) determine the prevalance and characterize the symptomatology of Trichomonas vaginalis (TV) infection in pregnant women on entry into prenatal care in an inner-city population; 2) compare conventional microscopic methods vs. culture techniques in diagnosing TV in both symptomatic and asymptomatic pregnant patients; and 3) correlate wet mount microscopic and microbiologic characteristics of varying manifestations of trichomoniasis.

Methods: One thousand two hundred sixty patients in an inner-city population were tested at entry into prenatal care for TV by saline wet mount and culture techniques. Other tests for lower genital tract infection were also performed. Vaginal symptoms were ascertained through standardized questioning prior to examination. Standard microscopic and microbiologic data were also obtained for analysis. Wet mounts were systematically examined and considered negative if no TV was identified in 10 high powerfields (HPFs). Cultures were inspected from days 4 to 7 or until positive results were obtained. Results were analyzed using McNemar's test for correlated proportions, chi-squared test, or Fisher exact test where appropriate.

Results: Culture and wet mount results were available in 1,175 patients. TV infection was documented by one or both techniques in 110/1,175 (9.4%). Culture methods detected 105/110 (94.5%) of all patients while wet mount detected 90/110 (73%) (P <0.001). Vaginal symptoms were present in only 20/110 patents (18.2%). Among asymptomatic patients, culture detected 94% while wet mount detected 70% (P < 0.001). Among symptomatic patients, wet mount and culture were both effective and diagnosed 85% and 95% of infections, respectively (P = not significant). Patients with TV were more likely to have increased vaginal fluid wlaite blood cells (WBCs) and more severe vaginal flora disruption than uninfected controls. Subgroup analysis revealed wet mount-positive/culture-positive patients were more likely to have vaginal flora disruption, as evidenced by decreased lactobacilli and elevated vaginal pH, than wet mount-negative/culture-positive subjects. Coexistent infection rates were similar regardless of wet mount status. Elevated vaginal fluid WBCs were more common among patients with symptoms.

Conclusions: 1) Screening pregnant women for TV based solely on symptomatology is ineffective in this population; 2) culture techniques detected more infections than conventional microscopic evaluation; and 3) significant increases in vaginal fluid WBCs and altered vaginal flora are found in both symptomatic and asymptomatic TV, suggesting that both infestations have the potential to adversely affect pregnancy outcome. Studies on the influence of TV on pregnancy outcomes are ongoing.

Does patient-delivered partner treatment improve disclosure for treatable sexually transmitted diseases?

The objective of this research was to determine the factors associated with disclosure of three treatable sexually transmitted diseases (STDs). Data were obtained from two intervention trials to determine the ideal means of partner referral. Men diagnosed with urethritis and women diagnosed with trichomoniasis at public clinics in New Orleans, Louisiana were randomly assigned to partner referral (PR), booklet-enhanced partner referral (BEPR), or patient-delivered partner treatment (PDPT). Participants were asked about sex partners at baseline, then whether they disclosed to them at follow-up. The male trial was conducted from December 2001 to March 2004 and the female trial from December 2001 to August 2004. Data on men and women were analyzed separately. Nine hundred seventy-seven men and 463 women-reporting information on 1991 and 521 sex partners-were respectively enrolled in each trial. Disclosure occurred to 57.8% and 87.3% of their partners, respectively. Most men (68.3%) reported having two or more partners and disclosure was more likely to occur in: those who reported only one sex partner (adjusted odds ratio [aOR] 95% confidence interval [CI]: 1.54 [1.10, 2.16]); those in steady relationships (OR [95% CI]: 1.37 [1.08,1.74]); and those assigned PDPT [OR [95% CI]: 2.71 [1.93,3.82]). Most women reported having only one partner (86.8%) and disclosure was more likely to occur in steady relationships (OR [95% CI]: 2.65 [1.24,5.66]), and when sex was reinitiated with partners during the follow-up period (OR [95% CI]: 3.30 [1.54,7.09]). The provision of PDPT was associated with increased STD disclosure among men but not among women. Both men and women were less likely to disclose to casual partners. Women had high rates of disclosure irrespective of intervention arm.

A randomized trial of the duration of therapy with metronidazole plus or minus azithromycin for treatment of symptomatic bacterial vaginosis

BACKGROUND

Bacterial vaginosis (BV) is the most common cause of vaginitis worldwide. Currently recommended treatments have poor efficacy and are associated with high rates of BV recurrence. We examined whether a longer duration of treatment with metronidazole or combination therapy with metronidazole and azithromycin would enhance the cure rates for BV. In addition, we examined factors other than drug therapy associated with cure.

METHODS

Women with symptomatic BV (defined by a modified Amsel criteria) were enrolled in a 4-arm study that compared metronidazole for 7 days versus 14 days, plus or minus azithromycin on days 1 and 3. Data regarding interim behaviors were also obtained, as were vaginal specimens for Gram staining.

RESULTS

At the first follow-up visit (7 days after the completion of therapy), there was a significant difference in cure rates among patients who received 7 days of metronidazole therapy, compared with those who received 14 days of therapy, combined across azithromycin therapy (P=.0003). There was no effect associated with azithromycin therapy. There were no differences in cure rates between any of the treatment groups at 21 days after completion of therapy. Abstinence or protected sex, refraining from douching, and a lower baseline Nugent score for the vaginal Gram stain were all significantly associated with cure.

CONCLUSIONS

Cure rates for BV were significantly improved by 14 days of metronidazole treatment (compared with 7 days of treatment), but the effects were not sustained, suggesting that relapse or reinfection occurred. Combination therapy with the addition of azithromycin had no benefit. Lower baseline Nugent scores--presumably reflecting less complex vaginal flora--were significantly associated with cure, as was refraining from unprotected sex and from douching.

Trichomonas vaginalis detection using real-time TaqMan PCR

1978 women and 93 men, all suspected of having a Trichomonas vaginalis infection, were tested for the presence of T. vaginalis by real-time PCR using the T. vaginalis-specific 2-kb repeated sequence, and by direct microscopy and culture. 40 samples were positive by T. vaginalis real-time PCR and 27 were positive by wet mount microscopy, either direct or after culture. All samples positive by direct microscopy of culture were also positive by real-time PCR. Of the 13 samples which were real-time PCR positive but negative by direct microscopy and culture 11 were confirmed by another T. vaginalis real-time PCR based on the beta tubulin gene. Only 2 samples (0.1%) showed inhibition in the PCR. The prevalence of T. vaginalis infection in the female patients was 1.8%. The sensitivity, specificity, positive and negative predictive values of the real-time PCR were 100%, 99.9%, 95% and 100%, respectively. The same test characteristics for the combined conventional T. vaginalis detection methods (microscopy+culture) were 71%, 100%, 100% and 99%, respectively. Therefore, real-time PCR is the method of choice for the diagnosis of T. vaginalis infection.

Treatment of sexually transmitted infections in pregnancy

Sexually transmitted infections remain a major public health concern in the United States. An estimated 19 million infections occur each year. The economic burden imposed by sexually transmitted infections is impressive: direct medical costs have been estimated as high as 15.5 billion US dollars annually. Sexually transmitted infections are relatively common during pregnancy, especially in indigent, urban populations. Education, screening, treatment, and prevention are important components of prenatal care for women at increased risk for these infections. Treatment of these sexually transmitted infections is clearly associated with improved pregnancy outcome and reductions in perinatal mortality.

Targeted screening for Trichomonas vaginalis with culture using a two-step method in women presenting for STD evaluation

OBJECTIVES

Trichomonas vaginalis is the most common nonviral sexually transmitted pathogen. Wet mount microscopy performs poorly compared with culture; however, universal screening using culture would be cost-prohibitive.

GOAL

The goal of this study was to develop a predictive model for wet mount-negative women who may benefit from targeted use of culture for T. vaginalis detection.

STUDY

Women presenting for sexually transmitted disease evaluation were prospectively screened for trichomoniasis using wet mount and culture. Multivariate logistic regression was used to identify predictors of culture-proven trichomoniasis among wet mount-negative women.

RESULTS

A total of 2194 women were screened for trichomoniasis; overall, the prevalence of T. vaginalis was 17.5%. Three predictors (any drug use, contact to trichomoniasis, and African-American race) provided the most specific model (100%); any 1 predictor, the most sensitive model (97.8%).

CONCLUSIONS

Given the public health impact of trichomoniasis, we recommend using any 1 of 3 predictors to identify women who would benefit from targeted culture for T. vaginalis.

Trichomoniasis

Trichomoniasis is perhaps the most common curable sexually transmitted disease worldwide, yet few resources are devoted to its control. It is associated with potentially serious complications such as preterm birth and human immunodeficiency virus acquisition and transmission. The immunology of a related organism, Tritrichomonas foetus, which causes disease in cattle, has been investigated to some extent, but more work is needed for the human strain, Trichomonas vaginalis. In addition, although trichomoniasis is easily treated with oral metronidazole, there is concern that the number of strains resistant to this antibiotic are increasing, and currently no alternative is licensed in the United States. As more is appreciated concerning the important public health implications of this common infection, more work will need to be done in understanding the diagnosis, treatment, and immunology of this organism.

Comparison of culture and different PCR assays for detection of Trichomonas vaginalis in self collected vaginal swab specimens

OBJECTIVES

DNA amplification techniques have become widely used for the diagnosis of sexually transmitted infections. For the detection of Trichomonas vaginalis, PCR techniques are not yet widely used despite the publication of several assays. The sensitivity and specificity of five independent primer sets were determined on self collected vaginal specimens obtained from female commercial sex workers.

METHODS

Self collected specimens were obtained from symptomatic and asymptomatic women attending a female sex workers clinic in Abidjan, Côte d'Ivoire. Two vaginal specimens were collected, the first one was processed for culture and the second was processed for PCR analysis. PCR techniques for trichomonads were performed, using the primers as reported by Riley (TVA5/TVA6), Kengne (TVK3/TVK7), Madico (BTUB 9/BTUB 2), Shiao (IP1/IP2), and Mayta (TV1/TV2). An EIA amplicon detection method was designed for each of the primer sets.

RESULTS

True positive specimens were defined as culture positive and/or two positive PCR results with EIA amplicon detection in any combination. According to this definition a prevalence of 20% was obtained compared to 7% obtained by culture. The PCR primer set TVK3/TVK7 gave the highest sensitivity (89.2%). Poor sensitivities were obtained with the primer sets TV1/TV2 (60.2%) and TVA5/TVA6 (63.9%). PCR showed a sensitivity improvement of 2.4% up to 12% when EIA was used for amplicon detection.

CONCLUSIONS

Overall, the sensitivities of the different PCR assays resulting from this study were lower than those previously described. These findings could be the result of the nature of the specimen population and suggests a strain variability.

A comparative evaluation of the Papanicolaou test for the diagnosis of trichomoniasis

BACKGROUND

Trichomoniasis is the most prevalent nonviral sexually transmitted disease in humans worldwide. In addition to its pathologic implications, trichomoniasis is a risk factor for the transmission of the HIV and is associated with reproductive complications in females. Diagnosis of the disease is problematic due to inadequate accuracy of current diagnostic methods. Recently developed DNA-based techniques for detection of Trichomonas vaginalis seem to be promising alternatives.

GOAL

The goal of this study was to evaluate the accuracy of the Papanicolaou test for the diagnosis of trichomoniasis by comparing polymerase chain reaction (PCR) with other current diagnostic methods.

STUDY DESIGN

A total of 1008 cervicovaginal swab specimens from a randomized population attending a gynecological service were analyzed in this study. In addition to current diagnostic methods, two sets of specific primers were used for PCR detection of T vaginalis in the cervicovaginal DNA samples, with a PCR quality control. Different examiners conducted PCR and Papanicolaou analyses in a double-blind trial.

RESULTS

The prevalence of trichomoniasis in this population was 6%. A considerable number of diagnostic results of the Papanicolaou test were false negative or false positive. Compared with PCR, specificity of the Papanicolaou test was 97.6%, whereas sensitivity was only 60.7%. The positive predictive value of the Papanicolaou smear was 61.7%. These results suggest that irregularly shaped parasites without clearly defined nuclei and flagella and bacteria-induced focal cytolysis limit the ability of the Papanicolaou test to detect T vaginalis.

CONCLUSION

The Papanicolaou test, the most readily available cytologic method for screening sexually transmitted pathogens and cellular abnormalities in most developing countries, is inadequate for the diagnosis of trichomoniasis due to its inherent limitations. However, PCR is a highly sensitive and specific test for the diagnosis of trichomoniasis.

Comparison of STD prevalences in the Mwanza, Rakai, and Masaka trial populations: the role of selection bias and diagnostic errors

OBJECTIVES

To assess bias in estimates of STD prevalence in population based surveys resulting from diagnostic error and selection bias. To evaluate the effects of such biases on STD prevalence estimates from three community randomised trials of STD treatment for HIV prevention in Masaka and Rakai, Uganda and Mwanza, Tanzania.

METHODS

Age and sex stratified prevalences of gonorrhoea, chlamydia, syphilis, HSV-2 infection, and trichomoniasis observed at baseline in the three trials were adjusted for sensitivity and specificity of diagnostic tests and for sample selection criteria.

RESULTS

STD prevalences were underestimated in all three populations because of diagnostic errors and selection bias. After adjustment, gonorrhoea prevalence was higher in men and women in Mwanza (2.8% and 2.3%) compared to Rakai (1.1% and 1.9%) and Masaka (0.9% and 1.8%). Chlamydia prevalence was higher in women in Mwanza (13.0%) compared to Rakai (3.2%) and Masaka (1.6%) but similar in men (2.3% in Mwanza, 2.7% in Rakai, and 2.2% in Masaka). Prevalence of trichomoniasis was higher in women in Mwanza compared to women in Rakai (41.9% versus 30.8%). Herpes simplex virus type 2 (HSV-2) seroprevalence and prevalence of serological syphilis (TPHA+/RPR+) were similar in the three populations but the prevalence of high titre syphilis (TPHA+/RPR >/=1:8) in men and women was higher in Mwanza (5.6% and 6.3%) than in Rakai (2.3% and 1.4%) and Masaka (1.2% and 0.7%).

CONCLUSIONS

Limited sensitivity of diagnostic and screening tests led to underestimation of STD prevalence in all three trials but especially in Mwanza. Adjusted prevalences of curable STD were higher in Mwanza than in Rakai and Masaka.

Accuracy of detection of trichomonas vaginalis organisms on a liquid-based papanicolaou smear

OBJECTIVE

The study was undertaken to determine the accuracy of the liquid-based Papanicolaou (Pap) smear in the detection of Trichomonas vaginalis organisms in women.

STUDY DESIGN

Two hundred three consecutive patients who had the liquid-based Pap smear also underwent a culture for T vaginalis. A wet mount was performed if symptomatic. Results were analyzed for sensitivity, specificity, and positive and negative predictive values.

RESULTS

Forty-four patients (21.6%) had a positive culture. On the liquid-based Pap smear, 28 patients (13.8%) were positive for T vaginalis, showing a sensitivity of 61.4%, a specificity of 99.4%, a positive predictive value of 96.4%, and a negative predictive value of 90.8%. When wet mount and culture were compared, a sensitivity of 50%, a specificity of 93%, a positive predictive value of 77%, and a negative predictive value of 80% were obtained.

CONCLUSION

The presence of T vaginalis organisms, as stated by the liquid-based Pap smear pathology report, is accurate and warrants treatment without further testing.

Acceptability of sexually transmitted infection screening among women in short-term substance abuse treatment

BACKGROUND

Substance abuse treatment centers provide an opportunity to offer sexually transmitted infection (STI) screening to a high-risk and hard-to-reach population.

GOAL

The goal was to assess STI prevalence, risk factors, and acceptability of STI screening among females at substance abuse treatment centers with use of urine testing by ligase chain reaction and self-collected swab specimens.

STUDY DESIGN

Adult, female inpatients were offered free testing and treatment for chlamydia infection, gonorrhea, and trichomonas infection. Interviews were conducted to collect risk behavior data.

RESULTS

Eighty-six percent of inpatients (180/209) accepted testing. Twenty-three percent (41/177) had an STI. Of those with an STI, 90% (37/41) had trichomonas infection. All 41 infected patients received treatment. Drug use before sex, exchange of sex for money/drugs, and any gynecological complaint were significantly associated with infection. Most women were uninsured (76%). Only 45% had undergone a medical examination in the past year.

CONCLUSION

STI screening is highly acceptable among women in substance abuse treatment centers. Substance users are at high risk for STIs and may not otherwise receive medical care.

Update of trichomoniasis

Trichomoniasis remains an extremely common infection despite the fact that rates of other treatable sexually transmitted diseases are declining. Newer diagnostic techniques such as polymerase chain reaction (PCR) are documenting higher rates of infection in heterosexual men than have been previously found with culture. Although data on the association of vaginal trichomoniasis with preterm birth are controversial, the association of trichomoniasis with HIV acquisition seems clear. Despite being a readily diagnosed and treated STD, trichomoniasis is not a reportable infection and control of the infection has received relatively little emphasis from public health STD control programmes. More recently, however, appreciation of high rates of disease and of associations of trichomoniasis in women with adverse outcomes of pregnancy and increased risk for HIV infection suggest a need for increased control efforts.

Timing of inoculation of the pouch makes no difference in increased detection of Trichomonas vaginalis by the InPouch TV method

The InPouch TV is a method which combines a wet preparation and a culture method to detect Trichomonas vaginalis. The top portion of the InPouch TV essentially functions as a slide to be examined under the microscope. If the initial examination is negative, the specimen is pushed down into the bottom pouch, which serves as a broth for cultivation. The issue of timing has not been specifically addressed for optimal processing. To assess the effect of timing on the inoculation of the bottom pouch, we conducted a study designed to determine which procedure had better sensitivity, that of delaying inoculation of the bottom pouch until the initial examination on the top pouch is performed (method A) or that of immediately inoculating the bottom pouch (method B). In addition, we compared the sensitivity of the InPouch TV to that of the traditional wet mount. Fifty of 498 specimens were positive. Methods A and B had identical results: 31 specimens were initially positive regardless of transit time, and incubation yielded another 19 positives. The wet preparation detected 36 positive specimens. The sensitivities of the methods were 100% for the InPouch TV (including examination on receipt and after incubation) and 72% for the traditional wet mount. In conclusion, the InPouch TV method is more sensitive than the traditional method and no detectable differences were observed with timing of the inoculation of the top or bottom pouch.

Interrelationships of bacterial vaginosis and cervical inflammation

BACKGROUND

Women with cervicitis frequently have bacterial vaginosis (BV). Prior studies have suggested that BV is involved in the pathogenesis of cervicitis.

GOALS

To delineate the association of BV and cervicitis and to determine whether treatment of BV results in increased resolution of cervicitis.

STUDY DESIGN

Women with clinically diagnosed cervicitis and BV received doxycycline and ofloxacin and were randomized to treatment with metronidazole gel or placebo. Resolution of BV and cervicitis was assessed.

RESULTS

Metronidazole gel was associated with resolution of BV. Resolution of cervicitis was associated with use of metronidazole gel versus placebo (24/27 [88.9%] versus 15/24 [62.5%]; P = 0.03). When further stratified by resolution of BV, those whose BV resolved were more likely to have resolution of cervicitis than those with persistent BV. Although these trends persisted in multivariate analyses, they did not achieve statistical significance.

CONCLUSION

Univariate analyses suggest an association between BV and cervicitis. An association between the use of metronidazole gel and resolution of cervicitis was demonstrated. Hypotheses regarding the latter include nonspecific antiinflammatory effects of metronidazole, its effect on BV flora, and its effect on a specific unrecognized pathogen.

TaqMan-based detection of Trichomonas vaginalis DNA from female genital specimens

A double-labeled fluorescent probe was designed and evaluated for detecting Trichomonas vaginalis DNA in a 5' nuclease (TaqMan) assay. The T. vaginalis-specific probe contains a 5'-fluorescein (5'-FAM) and a 3'-rhodamine (TAMRA) derivative. Female genital secretions were collected on Amplicor (Roche Molecular, Indianapolis, Ind.) swabs and by a transport system used for Chlamydia trachomatis and/or Neisseria gonorrhoeae DNA detection by PCR. Five hundred fifty-two female genital specimens, of which 248 (45%) were vaginal specimens and 304 (55%) were introital, were tested for both T. vaginalis DNA and viable microorganisms using the 5' nuclease assay and broth culture, respectively. Of these, 304 of 552 (55%) were also evaluated by direct microscopic examination for the characteristic motile organism. After resolving discrepancies, the comparisons produced an analytical sensitivity and specificity for the TaqMan-based PCR assay of 97.8 and 97.4%, respectively. As a result, DeltaRQ values (differences in fluorescence due to probe hybridization and resulting 5'-FAM cleavage from the specific PCR product) of > or =2.0 and < or =1.5 were established for T. vaginalis-positive and -negative cutoffs, respectively. DeltaRQ values between 1.5 and 2.0 were considered indeterminate. Overall findings revealed a high level of agreement between PCR and culture for detecting T. vaginalis. Potential benefits of the 5' nuclease assay include a greater sensitivity compared to direct microscopic examination and the ease of testing large numbers of clinical specimens in a significantly shorter turnaround time compared to culture.

The Bali STD/AIDS study: association between vaginal hygiene practices and STDs among sex workers

OBJECTIVES

To assess the association between genital cleansing practices and the prevalence of sexually transmitted diseases and of sexual health knowledge among female sex workers in Bali, Indonesia.

METHODS

Low priced commercial sex workers (CSWs) participated in the Bali STD/AIDS Study, a 3 year educational project evaluating the effect of education on the subsequent use of condoms and the prevalence of STDs and AIDS. Structured interviews, genital evaluation, laboratory evaluation for STDs, and treatment were performed. Vaginal cleansing characteristics including frequency, type, and reasons for use, were evaluated. Associations between these characteristics and the presence of bacterial and viral genital infections were assessed.

RESULTS

Of 625 female sex workers evaluated between May and July 1998, 99.1% used substances, such as soap and toothpaste, to clean the vagina at least daily, with 69.3% performing this after each intercourse. The women using such cleansers after each client did not differ from those using them once or less daily in education, AIDS and condom use knowledge, time working as a CSW, or number of clients in the previous day. However, they were younger than those using vaginal cleansers daily or less, and reported lower condom usage in the past week. Several genital symptoms, such as discoloured discharge and odour, were reported less by women with the highest frequency of vaginal cleanser use. Prevalence of genital infections in this population of women was substantial, with bacterial infections more prevalent than viral infections. Infections were not associated with the type of cleanser used, using a genital cleanser on the day of examination, or using a cleanser after each client versus daily or less, except for candida colonisation, which was more prevalent in women cleansing after each client (OR=1.87, 95% CI 1.21, 2.90). However, symptomatic candida vulvovaginitis (positive culture plus presence of symptoms) was not associated with the prevalence of genital cleansing. Women using genital cleansing in part for "infection avoidance" (39.7%) were more likely to have heard of STDs and AIDS, but were less knowledgeable about these infections, compared with women not citing this reason for genital cleansing.

CONCLUSION

Commercial sex workers in low priced brothels in Bali have a high rate of genital infections, with lower rates of viral compared with bacterial infections. Genital cleansers, on a daily or after each intercourse schedule, are used routinely. Although genital cleansing after each intercourse was associated with fewer genital symptoms, the prevalence of STDs did not differ significantly based on this frequency, and the women's knowledge of STDs and AIDS was less than that of women cleansing less often. The effect of genital cleansing in general on STD and AIDS prevalence could not be assessed in this population owing to the lack of a non-cleansing cohort. Further study to elucidate the effect of vaginal cleansing practices on STD prevalence and resistance is needed.

Asymptomatic bacterial vaginosis: response to therapy

OBJECTIVE

Bacterial vaginosis causes symptomatic vaginal discharge and has been associated with preterm birth and with the acquisition of human immunodeficiency virus. Half of all women with bacterial vaginosis are free of symptoms, and treatment of these women is controversial. The objective of this study was to determine the extent of poor symptom recognition in this group of women.

STUDY DESIGN

Seventy-five women attending a sexually transmitted disease clinic who had asymptomatic bacterial vaginosis were entered into a randomized, double-blind, placebo-controlled trial comparing metronidazole gel with placebo. Subjects' perceptions about changes in vaginal discharge and odor were determined, and treatment and placebo groups were compared by means of standard statistical analysis.

RESULTS

When subjects were stratified by treatment group, there were no differences in their retrospective assessments of vaginal discharge and odor. A subset of women who had normalization of clinical parameters or of Gram stain scores did admit retrospectively to improvement; however, the difference between this group and the group without normalization was not statistically significant. Twenty-one percent of treated women subsequently had vaginal candidiasis.

CONCLUSIONS

A greater percentage of women with resolution of bacterial vaginosis did retrospectively notice improvement in vaginal discharge and odor in comparison with those women without resolution; however, this was not statistically significant. These findings do not support routine treatment of women with asymptomatic bacterial vaginosis.

High prevalence of trichomoniasis in rural men in Mwanza, Tanzania: results from a population based study

OBJECTIVES

To measure the prevalence of urethral infections including trichomoniasis in rural Tanzanian men, to assess the prevalence of symptoms and signs among men with Trichomonas vaginalis, and to analyse the risk factors for trichomoniasis.

DESIGN

A cross sectional study of 1004 men aged 15-54 years in a rural community in north west Tanzania.

METHODS

Participants were interviewed about sexual behaviour and symptoms of sexually transmitted diseases. First fraction urine samples and urethral swabs were collected and used to test for T vaginalis by wet preparation and culture, Neisseria gonorrhoeae by culture, Chlamydia trachomatis by ligase chain reaction and non-specific urethritis by Gram stain. Urine was also tested for the presence of leucocytes using a leucocyte esterase dipstick. Men were re-interviewed 2 weeks later to document new symptoms and signs of urethritis.

RESULTS

Complete laboratory results were available on 980 men. One in four men had laboratory evidence of urethritis. T vaginalis was found in 109 individuals (11%), gonorrhoea in eight (0.8%), and chlamydial infection in 15 (1.5%). Over 50% of men with urethritis were asymptomatic. The prevalence of signs and symptoms was similar among men with T vaginalis alone compared with men with other urethral infections. The sensitivity and specificity of the leucocyte esterase dipstick (LED) test for detecting T vaginalis were 80% and 48% respectively in symptomatic men and 60% and 68% in asymptomatic men. Factors associated with trichomoniasis included religion, type of employment, and marital status.

CONCLUSIONS

A high prevalence of urethritis was found in men in this community based study. More than half of the urethral infections detected were asymptomatic. The most prevalent pathogen was T vaginalis. Studies are needed on the prevalence of trichomoniasis in men presenting to health services with complaints suggestive of urethritis since treatment for T vaginalis is not included in the syndromic management of urethritis in most countries. The performance of the LED test as a screening test for trichomoniasis was unsatisfactory in both symptomatic and asymptomatic men. Improved screening tests are urgently needed to identify urethral infections that are asymptomatic and which are not covered by current syndromic management algorithms.

Sexually transmitted diseases in adolescents

Sexually transmitted diseases (STDs) are among the top 10 reportable diseases in the United States. Of the more than 12 million cases annually, approximately 3 million occur in adolescents. An estimated two thirds of cases occur in individuals younger than age 25. Almost half of adolescents report ever being sexually active, and approximately one third are currently sexually active. For a number of biologic and psychosocial reasons, sexually active adolescents have the highest rate of STDs of any sexually active age group. They suffer from the acute manifestations of these diseases as well as complications that place them at risk for some significant long-term negative sequelae, such as infertility, chronic pelvic pain, and cancer. This article reviews the reasons for this increased risk and provides updates on the common STDs that affect adolescents.

A meta-analysis of the Papanicolaou smear and wet mount for the diagnosis of vaginal trichomoniasis

PURPOSE

To obtain reliable estimates of the sensitivity and specificity of the cervical Papanicolaou (Pap) smear and wet mount to diagnose vaginal trichomoniasis.

METHODS

Articles indexed in MEDLINE (1976-1998) about diagnostic tests for trichomoniasis and their listed references were retrieved. Thirty studies (9,501 patients) that used trichomonas culture as a gold standard were selected. Studies were defined as level I if they fulfilled at least two of the following three criteria: consecutive patients were evaluated prospectively, the decision to culture was not influenced by test results, and there was independent and blind comparison with culture. Studies were classified as level II if one criterion was fulfilled, and as level III otherwise.

RESULTS

The pooled sensitivity of the Pap smear for the diagnosis of trichomoniasis among level I studies was 57% (95% confidence interval [CI]: 51% to 63%) and the pooled specificity was 97% (95% CI: 93% to 100%). The likelihood ratio for a positive Pap smear was 19 among level I studies (range: 8 to 62). The pooled sensitivity of the wet mount among level I studies was 58% (95% CI: 51% to 66%); among level II studies, the sensitivity was 72% (95% CI: 62% to 81%), and among level III studies, the sensitivity was 82% (95% CI: 67% to 97%). The overall specificity of the wet mount was 99.8%.

CONCLUSIONS

A positive Pap smear for trichomonads in settings in which trichomoniasis is common (prevalence > or =20%) requires treatment. A positive Pap smear is indeterminate when the prevalence of trichomoniasis is about 10%; thus, clinicians should either confirm the diagnosis by culture or treat all such patients, recognizing that some patients will be treated unnecessarily. A culture should be obtained in women with a positive Pap smear who are unlikely to have trichomoniasis (prevalence < or =1%). While a positive wet mount is diagnostic, a negative wet mount does not exclude trichomoniasis.

Systematic review of diagnostic tests for vaginal trichomoniasis

OBJECTIVE

To review critically and to summarize the evidence of diagnostic tests and culture media for the diagnosis of Trichomonas vaginitis.

METHODS

We performed a systematic review of literature indexed in MEDLINE of studies that used Trichomonas culture as the reference standard (9,882 patients, 35 studies). Level I studies (5,047 patients, 13 studies) fulfilled at least two of three criteria: 1) consecutive patients were evaluated prospectively, 2) decision to culture was not influenced by test results, and 3) there was independent and blind comparison to culture.

RESULTS

The sensitivity of the polymerase chain reaction technique (PCR) was 95% (95% CI 91% to 99%), and the specificity was 98% (95% CI 96% to 100%). One study was classified as Level I evidence (52 patients). The sensitivity of the enzyme-linked immunosorbent assay was 82% (95% CI 74% to 90%), and the specificity was 73% (95% CI 35% to 100%). The sensitivity of the direct fluorescence antibody was 85% (95% CI 79% to 90%), and the specificity was 99% (95% CI 98% to 100%). Sensitivities of culture media were 95% for Diamond's, 96% for Hollander, and 95% for CPLM.

CONCLUSIONS

The sensitivity and specificity of tests to diagnose trichomoniasis vary widely.

Improved diagnosis of Trichomonas vaginalis infection by PCR using vaginal swabs and urine specimens compared to diagnosis by wet mount microscopy, culture, and fluorescent staining

Four vaginal cotton swab specimens were obtained from each of 804 women visiting the outpatient sexually transmitted disease clinic of the Erasmus University Medical Center Rotterdam, Rotterdam, The Netherlands, for validation of various forms of Trichomonas vaginalis diagnostic procedures. One swab specimen was immediately examined by wet mount microscopy, a second swab was placed in Kupferberg's Trichosel medium for cultivation, and two swabs were placed in phosphate-buffered saline (PBS), pH 7.2. The resulting PBS suspension was used for direct staining with acridine orange and fluorescence microscopy, inoculation of modified Diamond's culture medium, and a PCR specific for T. vaginalis. A total of 70 samples positive in one or more of the tests were identified: 31 (3.8%) infections were detected by wet mount microscopy, and 36 (4.4%) were identified by acridine orange staining, as opposed to 40 (4.9%) and 46 (5.7%) positives in modified Diamond's and Trichosel media, respectively. PCR was positive for 61 (7.5%) samples. Secondly, from each of 200 women were obtained a urine sample and a vaginal cotton swab specimen, and 200 urine samples were obtained from men. For the women, 15 (7.4%) of the samples showed a positive result for either the wet mount (n = 1), Trichosel culture (n = 6), PCR on the vaginal swab sample (n = 10), or PCR on the urine specimen (n = 11). Four men (2%) were diagnosed with a T. vaginalis infection. Thus, PCR appears to be the method of choice for the detection of genital infections with T. vaginalis.

Trichomoniasis in pregnant human immunodeficiency virus-infected and human immunodeficiency virus-uninfected congolese women: prevalence, risk factors, and association with low birth weight

OBJECTIVE

We sought to assess the prevalence of and risk factors for vaginal trichomoniasis in human immunodeficiency virus-infected and human immunodeficiency virus-uninfected pregnant Congolese women and its relationship to pregnancy outcomes.

STUDY DESIGN

We performed a nested case-control study of 215 infected and 206 uninfected mothers who responded to questionnaires, underwent sexually transmitted disease testing (including culture for trichomoniasis shortly after delivery), and underwent assessment of infant outcomes. Maternal variables and birth outcomes were assessed according to presence or absence of trichomoniasis and human immunodeficiency virus.

RESULTS

Trichomoniasis was present in 18.6% of human immunodeficiency virus-positive and 10.2% of human immunodeficiency virus-negative women, respectively (odds ratio, 2.0; 95% confidence interval, 1.1-3.6), and was significantly associated with low birth weight (odds ratio, 2.4; 95% confidence interval, 1.2-4.5). In multivariate analyses trichomoniasis remained associated with low birth weight, and adjustments were made for other risk factors associated with low birth weight.

CONCLUSION

These findings suggest an association between trichomoniasis and low birth weight independent of human immunodeficiency virus infection and other risk factors. Further studies are needed to assess the impact of antenatal screening and treatment for trichomoniasis on pregnancy outcomes.

Trichomonas vaginalis as a cause of urethritis in Malawian men

BACKGROUND AND OBJECTIVES

Trichomonas vaginalis is one of the most common sexually transmitted infections. In Malawi, rates of trichomoniasis in women are high. The prevalence of T. vaginalis infection in men is expected to be high but has not previously been documented.

GOALS

We sought to determine the prevalence of trichomoniasis in Malawian men with and without urethritis, to evaluate a polymerase chain reaction detection assay for T. vaginalis in urethral swabs and to examine the effect of T. vaginalis infection on excretion of human immunodeficiency virus (HIV) in semen.

STUDY DESIGN

Men presenting at the Sexually Transmitted Diseases (STD) and Dermatology Clinics in Malawi were enrolled in a cross-sectional study. We compared a polymerase chain reaction-based test for T. vaginalis detection with wet-mount microscopy and culture of urethral swabs. HIV serology was determined by enzyme-linked immunosorbent assay (ELISA), and HIV-1 RNA concentrations in semen were measured by quantitative nucleic acid sequence-based analysis.

RESULTS

T. vaginalis was detected in 51 of 293 men. The estimated prevalence among symptomatic men was 20.8% and among asymptomatic men, 12.2%. Polymerase chain reaction performed with a sensitivity of 0.82 (95% CI: 0.66-0.92) and specificity of 0.95 (95% CI: 0.91-0.97) compared to wet-mount microscopy and culture. There was no difference in the rate of HIV seropositivity in men with and without T. vaginalis infection. However, in men with symptomatic urethritis, the median HIV RNA concentration in seminal plasma from men with T. vaginalis was significantly higher that in seminal plasma from HIV-positive men without trichomonas.

Asymptomatic non-ulcerative genital tract infections in a rural Ugandan population

OBJECTIVE

To document the prevalence of asymptomatic non-ulcerative genital tract infections (GTI) in a rural African cohort.

METHODS

The study population consisted of all adults aged 15-59 residing in 56 rural communities of Rakai District, southwest Uganda, enrolled in the Rakai STD Control for AIDS Prevention Study. Participants were interviewed about the occurrence of vaginal or urethral discharge and frequent or painful urination in the previous 6 months. Respondents were asked to provide blood and a first catch urine sample. Serum was tested for HIV-1. Urine was tested with ligase chain reaction (LCR) for N gonorrhoeae and C trachomatis. Women provided two self administered vaginal swabs; one for T vaginalis culture and the other for a Gram stained slide for bacterial vaginosis (BV) diagnosis.

RESULTS

A total of 12,827 men and women were enrolled. Among 5140 men providing specimens, 0.9% had gonorrhoea and 2.1% had chlamydia. Among 6356 women, 1.5% had gonorrhoea, 2.4% had chlamydia, 23.8% were infected with trichomonas and 50.9% had BV.53% of men and 66% of women with gonorrhoea did not report genital discharge or dysuria at anytime within the previous 6 months. 92% of men and 76% of women with chlamydia and over 80% of women with trichomonas or BV were asymptomatic. The sensitivities of dysuria or urethral discharge for detection of infection with either gonorrhoea or chlamydia among men were only 21.4% and 9.8% respectively; similarly, among women the sensitivity of dysuria was 21.0% while that of vaginal discharge was 11.6%. For trichomonas or BV the sensitivity of dysuria was 11.7% and that of vaginal discharge was 10.5%.

CONCLUSION

The prevalence of non-ulcerative GTIs is very high in this rural African population and the majority are asymptomatic. Reliance on reported symptoms alone would have missed 80% of men and 72% of women with either gonorrhoea or chlamydia, and over 80% of women with trichomonas or BV. To achieve STD control in this and similar populations public health programmes must target asymptomatic infections.

Diagnosis of Trichomonas vaginalis infection by PCR using vaginal swab samples

Trichomonas vaginalis infection is the most prevalent nonviral sexually transmitted disease (STD) in the world. A PCR test using vaginal swab samples for the detection of T. vaginalis was developed to add T. vaginalis infection to the growing list of STDs that can be detected by DNA amplification techniques. A primer set, BTUB 9/2, was designed to target a well-conserved region in the beta-tubulin genes of T. vaginalis. All strains (15 of 15) of T. vaginalis tested were successfully detected by PCR giving a single predicted product of 112 bp in gel electrophoresis. No such targeted product was amplified with DNA from Trichomonas tenax, Trichomonas gallinae, Chlamydia trachomatis, Neisseria gonorrhoeae, Giardia lamblia, Chilomastix sulcatus, Dientamoeba fragilis, and Entamoeba histolytica. An optimal analytical sensitivity of one T. vaginalis organism per PCR was achieved. Culture, performed with the Inpouch TV culture system, was examined daily with a light microscope to identify T. vaginalis. Twenty-three of 350 (6.6%) vaginal swab samples from women attending an army medical clinic were culture positive for T. vaginalis. Of these culture positive specimens, PCR detected 22 of 23 (96%) with primer set BTUB 9/2, and wet preparation detected only 12 of 23 (52%). Seventeen specimens were BTUB 9/2-PCR positive and culture negative. Ten of these discordant specimens were determined to be as true positive by PCR using primer sets TVA 5-1/6 and/or AP65 A/B, which target different regions in the T. vaginalis genome, and seven were determined to be false positive. The sensitivity of BTUB 9/2-PCR was 97% and the specificity was 98%. The sensitivities of culture and wet preparation were 70 and 36%, respectively. The diagnosis of T. vaginalis infection by PCR is a sensitive and specific method that could be incorporated into a joint strategy for the screening of multiple STDs by using molecular amplification methods.

A randomized, community trial of intensive sexually transmitted disease control for AIDS prevention, Rakai, Uganda

OBJECTIVE

To describe the design and first-round survey results of a trial of intensive sexually transmitted disease (STD) control to reduce HIV-1 incidence.

STUDY DESIGN

Randomized, controlled, community-based trial in Rakai District, Uganda.

METHODS

In this ongoing study, 56 communities were grouped into 10 clusters designed to encompass social/sexual networks; clusters within blocks were randomly assigned to the intervention or control arm. Every 10 months, all consenting resident adults aged 15-59 years are visited in the home for interview and sample collection (serological sample, urine, and, in the case of women, self-administered vaginal swabs). Sera are tested for HIV-1, syphilis, gonorrhea, chlamydia, trichomonas and bacterial vaginosis. Following interview, all consenting adults are offered directly observed, single oral dose treatment (STD treatment in the intervention arm, anthelminthic and iron-folate in the control arm). Treatment is administered irrespective of symptoms or laboratory testing (mass treatment strategy). Both arms receive identical health education, condom and serological counseling services.

RESULTS

In the first home visit round, the study enrolled 5834 intervention and 5784 control arm subjects. Compliance with interview, sample collection and treatment was high in both arms (over 90%). Study arm populations were comparable with respect to sociodemographic and behavioral characteristics, and baseline HIV and STD rates. The latter were high: 16.9% of all subjects were HIV-positive, 10.0% had syphilis, and 23.8% of women had trichomonas and 50.9% had bacterial vaginosis.

CONCLUSIONS

Testing the effects of STD control on AIDS prevention is feasible in this Ugandan setting.

Rates of and risk factors for trichomoniasis among pregnant inmates in New York City

BACKGROUND

Trichomonas vaginalis is a common pathogen that is associated with adverse pregnancy outcomes and may serve as a cofactor in human immunodeficiency virus (HIV) transmission.

GOAL

To define the epidemiology of trichomoniasis in a population of newly incarcerated pregnant women in New York City.

STUDY DESIGN

Prospective study of 213 pregnant prisoners attending prenatal clinic. Patients participated in an interview regarding sexual and drug-related behaviors, and underwent direct culture for T. vaginalis in addition to routine testing for syphilis, gonorrhea, and chlamydia.

RESULTS

The prevalence of trichomoniasis was 46.9%. On univariate analysis, there was a significant association between trichomoniasis and older age, crack use, prostitution, known HIV infection, and positive serological test for syphilis. Multivariate analysis showed a significant association of trichomoniasis with crack use and positive serological test for syphilis.

CONCLUSION

Trichomoniasis is highly prevalent in pregnant prisoners in New York City. The extent of disease observed may justify a formal program of testing and treatment and emphasizes the urgent need for harm reduction education and expanded HIV counseling and testing services in this high-risk population.

Evaluation and management of vaginitis

OBJECTIVE

To evaluate recent advances in our understanding of the clinical relevance, diagnosis, and treatment of vaginal infections, and to determine an efficient and effective method of evaluating this clinical problem in the outpatient setting.

DATA SOURCES

Relevant papers on vaginitis limited to the English language obtained through a MEDLINE search for the years 1985 to 1997 were reviewed.

DATA SYNTHESIS

Techniques that enable the identification of the various strains of candida have helped lead to a better understanding of the mechanisms of recurrent candida infection. From this information a rationale for the treatment of recurrent disease can be developed. Bacterial vaginosis has been associated with complications, including upper genital tract infection, preterm delivery, and wound infection. Women undergoing pelvic surgery, procedures in pregnancy, or pregnant women at risk of preterm delivery should be evaluated for bacterial vaginosis to decrease the rate of complications associated with this condition. New, more standardized criteria for the diagnosis of bacterial vaginosis may improve diagnostic consistency among clinicians and comparability of study results. Use of topical therapies in the treatment of bacterial vaginosis are effective and associated with fewer side effects than systemic medication. Trichomonas vaginalis, although decreasing in incidence, has been associated with upper genital tract infection. Therapy of T. vaginalis infection has been complicated by an increasing incidence of resistance to metronidazole.

CONCLUSIONS

Vaginitis is a common medical problem in women that is associated with significant morbidity and previously unrecognized complications. Research in recent years has improved diagnostic tools as well as treatment modalities for all forms of vaginitis.

Diagnosis of Trichomonas vaginalis in adolescent females: InPouch TV culture versus wet-mount microscopy

PURPOSE

This study compared the InPouch TV culture to wet-mount, Diamond's culture medium, and Papanicolaou (Pap) smear for the diagnosis of trichomonas infection in sexually active adolescents.

METHODS

A total of 467 subjects were recruited among 12-18-year-old girls who received pelvic examinations at two urban adolescent clinics. All girls were tested by wet-mount and InPouch TV. In addition 339 of 467 had cultures in Diamond's medium and 366 of 467 had Pap smears. Specimens were collected for InPouch TV and Diamond's cultures and read at 24-48 h and 5 days, and in the case of Diamond's cultures, also at 7 days. In a subset of subjects (268 of 467) who had all four tests done, sensitivities and specificities were calculated using Diamond's culture as the "gold standard."

RESULTS

In the 467 subjects, 73 (15.6%) tested positive for trichomonas by at least one method. In the subset with all four tests done, sensitivities of the wet-mount and InPouch TV were 36% and 81%, respectively; while that of the Pap smear was 56%. The culture media were equally efficient in identifying Trichomonas vaginalis. There were no differences found between subjects with or without trichomonas infections in gynecological symptoms, previous history of sexually transmitted diseases, or use of a condom at last intercourse.

CONCLUSIONS

InPouch TV culture is a good diagnostic method for T. vaginalis because of its long shelf-life, relatively low expense, and high sensitivity (over twice as sensitive as wet-mount).

Comparison of the InPouch TV culture system and Diamond's modified medium for detection of Trichomonas vaginalis

This study compared the use of Diamond's modified medium to InPouch for the culture of Trichomonas vaginalis from pooled vaginal secretions. The sensitivity for InPouch was 82.4% (61/74) versus 87.8% (65/74) for Diamond's modified medium. There were no significant differences in the sensitivity and negative predictive value of InPouch compared to Diamond's modified medium.

HIV-1 infection associated with abnormal vaginal flora morphology and bacterial vaginosis

BACKGROUND

In-vitro research has suggested that bacterial vaginosis may increase the survival of HIV-1 in the genital tract. Therefore, we investigated the association of HIV-1 infection with vaginal flora abnormalities, including bacterial vaginosis and depletion of lactobacilli, after adjustment for sexual activity and the presence of other sexually transmitted diseases (STDs).

METHODS

During the initial survey round of our community-based trial of STD control for HIV-1 prevention in rural Rakai District, southwestern Uganda, we selected 4718 women aged 15-59 years. They provided interview information, blood for HIV-1 and syphilis serology, urine for detection of Chlamydia trachomatis and Neisseria gonorrhoeae, and two self-administered vaginal swabs for culture of Trichomonas vaginalis and gram-stain detection of vaginal flora, classified by standardised, quantitative, morphological scoring. Scores 0-3 were normal vaginal flora (predominant lactobacilli). Higher scores suggested replacement of lactobacilli by gram-negative, anaerobic microorganisms (4-6 intermediate; 7-8 and 9-10 moderate and severe bacterial vaginosis).

FINDINGS

HIV-1 frequency was 14.2% among women with normal vaginal flora and 26.7% among those with severe bacterial vaginosis (p < 0.0001). We found an association between bacterial vaginosis and increased HIV-1 infection among younger women, but not among women older than 40 years; the association could not be explained by differences in sexual activity or concurrent infection with other STDs. The frequency of bacterial vaginosis was similar among HIV-1-infected women with symptoms (55.0%) and without symptoms (55.7%). The adjusted odds ratio of HIV-1 infection associated with any vaginal flora abnormality (scores 4-10) was 1.52 (95% CI 1.22-1.90), for moderate bacterial vaginosis (scores 7-8) it was 1.50 (1.18-1.89), and for severe bacterial vaginosis (scores 9-10) it was 2.08 (1.48-2.94).

INTERPRETATION

This cross-sectional study cannot show whether disturbed vaginal flora increases susceptibility to HIV-1 infection. Nevertheless, the increased frequency of HIV-1 associated with abnormal flora among younger women, for whom HIV-1 acquisition is likely to be recent, but not among older women, in whom HIV-1 is likely to have been acquired earlier, suggests that loss of lactobacilli or presence of bacterial vaginosis may increase susceptibility to HIV-1 acquisition. If this inference is correct, control of bacterial vaginosis could reduce HIV-1 transmission.

Colorimetric one-tube nested PCR for detection of Trichomonas vaginalis in vaginal discharge

A colorimetric one-tube nested PCR was developed for the detection of Trichomonas vaginalis in clinical vaginal discharge specimens. A family of 650-bp specific DNA repeats from the T. vaginalis genome was targeted. There was no cross-reaction with human DNA or other infectious agents, including Pentatrichomonas hominis and Giardia lamblia. The colorimetric assay was applied as an adjunct to nested PCR for semiquantitative determination of T. vaginalis DNA at levels corresponding to 1 to 1,000 parasites. PCR of samples prepared by a rapid boiling method was as sensitive and specific as PCR of samples prepared by the standard DNA extraction method: the equivalent of one T. vaginalis organism in 20 microliters of vaginal discharge could be detected. The colorimetric nested PCR was compared with wet mount and culture for the detection of T. vaginalis. A total of 378 clinical vaginal discharge specimens from symptomatic patients were examined; 31 patients were positive for T. vaginalis both by culture and by nested PCR. However, only 17 of these 31 patients were positive by wet mount examination. In addition, of 113 asymptomatic patients, 9 were positive for T. vaginalis by nested PCR. Of these nine PCR-positive patients, only two were also positive both by wet mount and by culture, four patients were positive by culture but negative by wet mount, and three patients were negative both by wet mount and by culture. No specimens negative by nested PCR were positive by wet mount or by culture. The three asymptomatic patients with PCR-positive but wet mount- and culture-negative samples were subsequently found to have T. vaginalis infection after repeated and prolonged culture was performed. This colorimetric nested PCR was very sensitive compared with culture for the diagnosis of vaginal trichomoniasis, especially asymptomatic T. vaginalis infection. It is also simple, specific, rapid, and semiquantitative.