Detection of human immunodeficiency virus type 1 (HIV-1) in genital ulcer exudate of HIV-1-infected men by culture and gene amplification

Differences in Syphilis Incidence Using a Laboratory Algorithm in People With and Without HIV in an 11-Year Nationwide Cohort Study

Background

To measure the incidence of syphilis diagnoses among people with HIV vs those without HIV in a national multiyear retrospective cohort.

Methods

Treponemal and nontreponemal tests, HIV status, and demographic data were identified among all individuals receiving Veterans Health Administration (VHA) care between January 1, 2009, and December 31, 2019. Syphilis testing rates and incident syphilis diagnoses as defined by a laboratory algorithm were stratified by HIV status.

Results

Syphilis was diagnosed in 1.2% (n = 2283) of 194 322 tested individuals in VHA care in 2019. Among individuals with HIV tested for syphilis, 6.1% met criteria for syphilis compared with 0.7% without HIV. Syphilis incidence in 2019 was 35/100 000, a 17% increase from 2009 (30/100 000). In 2019, syphilis incidence was 3381 per 100 000 persons among individuals with HIV and 19 per 100 000 in those without HIV.

Conclusions

Using a laboratory-based diagnostic algorithm, a 178-fold difference in syphilis incidence was observed between individuals with and without HIV in 2019. US syphilis incidence data that incorporate HIV status are needed. Interventions to monitor and prevent sexually transmitted infections should address the role of HIV status.

Sexually transmitted diseases of the anus and rectum: Causal agents, coinfections, HIV infection and high-risk sexual behaviour

INTRODUCTION AND OBJECTIVE

Sexually transmitted infections of the rectum and anus (STI-RA) mainly affect men who have sex with men (MSM). The incidence of STI-RA among them has increased in recent years.

MATERIAL AND METHODS

Retrospective study in patients with diagnoses of STI-RA in an STI unit during the years 2014 and 2015. Epidemiological, clinical and microbiological data were collected.

RESULTS

We included 95 patients, all of whom were MSM; 88.42% were HIV+; 67.17% did not use a condom during their most recent sexual intercourse; 17.91% had had sex with sex workers and 72.22% had used drugs during sexual intercourse during the previous year. A percentage of 32.92 reported symptoms that had lasted longer than 30 days. Lymphogranuloma venereum (LGV) was diagnosed in 54.73% of the patients. All patients who presented with proctitis and perianal ulcers were diagnosed with LGV infection. All those who presented perianal ulcers without proctitis were diagnosed with syphilis.

CONCLUSIONS

All the patients affected by STI-RA were MSM, most of them HIV+, had engaged in high-risk sexual behaviour and had suffered prolonged symptomatology. Clinical and microbiological characteristics of STI-AR could help adjust the empiric therapy.

Heterosexual transmission of human immunodeficiency virus infection - Strategies for prevention

In Canada, over 90% of the acquired immune deficiency syndrome cases diagnosed so far have been acquired sexually, with an increasing proportion made up of heterosexual contacts of high risk individuals. In multiple studies, the transmission rate among steady heterosexual partners of infected individuals has been variable. It is likely that complex biological and epidemiological interactions exist between human immunodeficiency virus (HIV) and sexually transmitted diseases with respect to transmission and disease. Other important determinants in transmission of infection may relate to the virus itself. The importance of sexual practices other than vaginal intercourse (such as anal intercourse) in the heterosexual transmission of HIV has not been well studied. The major approach to the control of HIV-associated disease remains the control of primary infection. Sexual practices which are the major epidemiological determinants of HIV transmission can be successfully modified by appropriate educational interventions. The promotion of condom use must form a special part of these interventions. Results of ongoing trials should be available prior to the formulation of recommendations for the use of spermicides. Targeted education programs may allow us to make better use of our resources in a more efficient way. In Canada, groups that could be reached by such programs include: prostitutes and their clients; men and women attending sexually transmitted disease clinics; sexually active women attending family planning clinics; and children and adolescents who are becoming sexually active.

The potential role of biomarkers in HIV preventive vaccine trials

BACKGROUND

Successful conduct of HIV vaccine efficacy trials entails identification and enrollment of at-risk populations, assessment of appropriate end points as measures of vaccine efficacy for prevention of HIV acquisition, and amelioration of disease course among infected vaccinees, as well as identification of potential confounders or effect modifiers. Although not invariably useful and bringing their own cost in terms of measurement and validation, a variety of biomarkers may aid at each stage of trial conduct.

METHODS

A review of selected articles, chosen based on quality, relevance of the biomarker to HIV vaccine trials, and availability of the publication, was conducted. The authors also drew experience from current trials and other planned or ongoing trials.

CONCLUSIONS

Biomarkers are available to assess HIV incidence in potential study populations, but care is needed in interpreting results of these assays. During trial conduct, sexually transmitted infections such as herpes simplex virus type 2 may act as effect modifiers on primary and secondary end points, including HIV incidence and set point viral load. The utility of sexually transmitted infection biomarkers will likely depend heavily on local epidemiology at clinical trial sites. Analyses from recent large HIV vaccine efficacy trials point to the complexities in interpreting trial results and underscore the potential utility of biomarkers in evaluating confounding and effect modification.

Comparison of lavage and swabs for the collection of genital ulcer specimens to measure HIV RNA shedding

BACKGROUND

The optimum collection procedure for the evaluation of HIV-1 burden in ulcer secretions has not been well defined.

OBJECTIVES

The objective of this study was to compare ulcer swabs and ulcer lavages for the detection and quantitation of HIV-1 RNA in genital ulcers.

STUDY DESIGN

A convenience sample of the first 84 HIV-positive participants in a randomized double blind placebo controlled trial of acyclovir episodic treatment among men with genital ulcer disease were included in this evaluation. At baseline, participants were screened for HIV, syphilis and HSV-2 by serology and for ulcer etiology by PCR. Ulcer specimens were collected by using (1) a non-traumatic washing procedure with 10ml of PBS, and (2) sterile dry swabs. Ulcer samples were tested with HIV-1 Amplicor 1.5 Ultra Sensitive Assay with a lower threshold of 50 copies/ml.

RESULTS

Of ulcer samples 35 (41.7%) had HIV detected by ulcer lavage and 32 (38.1%) by swabs (p=0.68). Overall, 45 (53.6%) were positive by one or both methods. The overall proportion of agreement was 73% (61/84). The chance-corrected proportion of agreement was 0.46 (95% CI: 0.26, 0.65) as estimated by the Kappa statistic. The log mean viral load from lavages (1.49log(10) copies/ml, 95% CI: 1.17-1.81) did not differ significantly from that of swabs (1.41log(10) copies/ml, 95% CI: 1.16-1.71) (p=0.29) with a mean difference of 0.08log copies/ml (SD 0.96).

CONCLUSION

Ulcer lavage and ulcer swab performed in moderate agreement in the detection and quantitation of HIV RNA from ulcer specimens.

The effect of genital tract infections on HIV-1 shedding in the genital tract: a systematic review and meta-analysis

This article reviews the effect of genital tract infections and associated clinical conditions on the detection and concentration of HIV-1 shedding in the genital tract. A search of the PubMed, Embase, and AIDSearch databases was conducted. Meta-analysis was performed on those studies that reported the effect of genital tract infections on the detection of HIV-1 shedding. Thirty-nine studies met the inclusion criteria. The odds of HIV-1 detection in the genital tract were increased most substantially by urethritis (OR 3.1, 95% CI: 1.1-8.6) and cervicitis (OR 2.7, 95% CI: 1.4-5.2). The odds of HIV-1 detection were also increased significantly in the presence of cervical discharge or mucopus (OR 1.8, 95% CI: 1.2-2.7), gonorrhoea (OR 1.8, 95% CI: 1.2-2.7), chlamydial infection (OR 1.8, 95% CI: 1.1-3.1), and vulvovaginal candidiasis (OR 1.8, 95% CI: 1.3-2.4). Other infections and clinical conditions were found to have no significant effect on the detection of HIV-1, although HSV-2 shedding was found to increase the concentration of HIV-1 shedding, and genital ulcer disease was found to increase the odds of HIV-1 detection significantly after excluding one biased study (OR 2.4, 95% CI: 1.2-4.9). This analysis shows that infections that are associated with significant increases in leukocyte concentrations in the genital tract are also associated with significant increases in HIV-1 shedding. These infections are likely to be particularly important in promoting the sexual transmission and mother-to-child intrapartum transmission of HIV-1, and should therefore be the focus of HIV prevention strategies.

STD treatment: how can it improve HIV prevention in the South?

BACKGROUND

Rates of human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS) and sexually transmitted diseases (STDs) are disproportionately high in the Southern United States. A high percentage of the population is black, and STD/HIV rates are particularly high among this group. Control and treatment of STDs offers promise as an HIV prevention strategy, and nowhere more than in the South.

OBJECTIVE

Identify those specific recommendations for control and treatment of STDs that available evidence indicates can reduce HIV transmission.

STUDY

Review of published literature.

RESULTS

Community trials produced inconsistent results but still suggest that STD treatment can reduce HIV transmission in the United States. Treatment of symptomatic STDs among those with HIV-infection should reduce HIV infectivity. There is as yet only limited evidence that STD treatment can reduce HIV susceptibility, although promising studies addressing herpes simplex virus are under way.

CONCLUSIONS

The unacceptably large racial disparities in STD rates must be addressed, symptomatic STDs among HIV-infected individuals treated, and syphilis prevention activities continued. Detection of unrecognized HIV infections among those seeking STD services should be a priority; identification of those with STDs and acute HIV infection may provide unique HIV prevention opportunities.

HIV/AIDS: Management of Herpes Simplex Virus Type 2 Infection in HIV Type 1–Infected Persons

Human immunodeficiency virus type 1 (HIV-1)-infected persons have high rates of herpes simplex virus type 2 (HSV-2) infection, ranging from 50% to 90% in studies of HIV-infected populations from different parts of the world. Genital herpes in persons with HIV type 1 (HIV-1) infection is associated with more-severe and chronic lesions, as well as increased rates of asymptomatic genital shedding of HSV-2. Nucleoside analogues (acyclovir, valacyclovir, and famciclovir) decrease the frequency and severity of HSV-2 recurrences and asymptomatic HSV-2 reactivation and are effective, safe, well-tolerated drugs in patients with HIV-1 infection. These anti-HSV drugs may result in additional clinical and public health benefits for persons with HIV-1 and HSV-2 coinfection by decreasing HIV-1 levels in the blood and genital tract. Given these benefits, HIV-1-infected persons should be routinely tested for HSV-2 infection using type-specific serologic tests. Persons with HSV-2 infection should be offered HSV-2 education and treatment options. Studies to quantify the potential clinical and public health benefits of treating individuals who have HIV-1 and HSV-2 coinfection with anti-HSV therapy are underway.

High rates of syphilis among STI patients are contributing to the spread of HIV-1 in India

BACKGROUND

Recent syphilis outbreaks have raised concern regarding the potential enhancement of HIV transmission. The incidence of syphilis and its association with HIV-1 infection rates among a cohort of sexually transmitted infection (STI) clinic attendees was investigated.

METHODS

2732 HIV-1 seronegative patients attending three STI and one gynaecology clinic, were enrolled from 1993-2000 in an ongoing prospective cohort study of acute HIV-1 infection in Pune, India. At screening and quarterly follow up visits, participants underwent HIV-1 risk reduction counselling, risk behaviour assessment and HIV/STI screening that included testing for serological evidence of syphilis by RPR with TPHA confirmation. Patients with genital ulcers were screened with dark field microscopy.

RESULTS

Among 2324 participants who were HIV-1 and RPR seronegative at baseline, 172 participants were found to have clinical or laboratory evidence of syphilis during follow up (5.4 per 100 person years, 95% CI 4.8 to 6.5 per 100 person years). Independent predictors of syphilis acquisition based on a Cox proportional hazards model included age less than 20 years, lack of formal education, earlier calendar year of follow up, and recent HIV-1 infection. Based on a median follow up time of 11 months, the incidence of HIV-1 was 5.8 per 100 person years (95% CI 5.0 to 6.6 per 100 person years). Using a Cox proportional hazards model to adjust for known HIV risk factors, the adjusted hazard ratio of HIV-1 infection associated with incident syphilis was 4.44 (95% CI 2.96 to 6.65; p<0.001).

CONCLUSIONS

A high incidence rate of syphilis was observed among STI clinic attendees. The elevated risk of HIV-1 infection that was observed among participants with incident syphilis supports the hypothesis that syphilis enhances the sexual transmission of HIV-1 and highlights the importance of early diagnosis and treatment of syphilis.

Syphilis epidemics and human immunodeficiency virus (HIV) incidence among men who have sex with men in the United States: implications for HIV prevention

Recent outbreaks of syphilis among men who have sex with men (MSM) in major cities in the United States and reported increases in sexual risk behavior have raised concerns about potential increases in human immunodeficiency virus (HIV) transmission. The majority of MSM who have early syphilis are HIV infected; in preliminary studies, rates of recent HIV infection among them are also high. Data from San Francisco, Los Angeles, and Seattle-King County, however, suggest no temporal increases in HIV incidence among MSM seeking HIV testing at select large public sites during the syphilis outbreaks. Because most HIV incidence and behavioral data are from large metropolitan areas with large gay populations and well-established HIV epidemics, we do not know whether, nationally, incidence of HIV infection among MSM has been increasing, decreasing, or stable during syphilis outbreaks. Further studies of HIV incidence in larger and smaller cities with different maturities of HIV epidemic are warranted. Comprehensive and integrated HIV/STD prevention and control efforts are also needed to halt the spread of syphilis and reduce HIV transmission among gay and bisexual men.

Developments in STD/HIV Interactions: The Intertwining Epidemics of HIV and HSV-2

Antiviral agents aimed at treating HSV-2 chronically infected individuals have proven to be effective in the prevention of symptomatic genital herpes and the reduction of viral shedding. These agents play a key role in current HIV prevention trials that will assess the role of suppression of HSV-2 infection on the risk for HIV acquisition and transmission. An added clinical benefit of treating HSV-2/HIV-coinfected individuals is the potential survival benefit, as suggested by earlier studies and by the recent findings that HSV-2/HIV dually infected individuals have higher viral loads. The results of the current HSV-2 suppression trials may provide additional tools to fight the global spread of HIV infection. Treatment of HSV-2/HIV dually infected individuals may prove to be a low-cost intervention to improve clinical outcomes and delay the need for antiretroviral therapy.

Management of vaginal discharge syndrome: how effective is our strategy?

Although syndromic management of sexually transmitted diseases in highly endemic areas provides a short-term benefit to the individuals treated, it has no impact on decreasing prevalence rates. The numerous factors that contribute to this are discussed. Rapid reinfection from a large pool of infected symptomatic and asymptomatic individuals as well as the non-specific nature of presenting symptoms in women with vaginal discharge syndrome are major causes.

Syphilis in the HIV-infected patient: An update on epidemiology, diagnosis, and management

After a decade of unprecedented declines, incidence of early-stage syphilis in the United States and Europe has increased significantly since 2000. These cases have occurred at disproportionately elevated rates among people infected with HIV. Speculation continues as to whether the clinical spectrum of syphilis is qualitatively different among those individuals who are HIV infected. Recent data suggest that individuals who are immune compromised because of HIV have a higher likelihood of developing neurosyphilis. Recommendations for treatment of syphilis remain the same for patients with and without HIV.

The role of sexually transmitted diseases in HIV transmission

More than 42 million people worldwide are now infected with HIV, in spite of sustained prevention activities. Although the spread of HIV has been primarily sexual, epidemiological studies have indicated that the efficiency of the spread of HIV is poor, perhaps as infrequently as 1 in every 1,000 episodes of sexual intercourse. However, sexually transmitted diseases (STDs) that cause ulcers or inflammation greatly increase the efficiency of HIV transmission--by increasing both the infectiousness of, and the susceptibility to HIV infection. STDs might be particularly important in the early stages of a localized HIV epidemic, when people with risky sexual behaviour are most likely to become infected. In China, eastern Europe and Russia, there has been a remarkable increase in the incidence of STDs in recent years, and this is reflected in the rapid increase in the spread of HIV in these areas. Targeted STD detection and treatment should have a central role in HIV prevention in these emerging epidemics.

Chancroid: clinical manifestations, diagnosis, and management

Chancroid is a sexually transmitted disease (STD) caused by the Gram negative bacterium Haemophilus ducreyi and is characterised by necrotising genital ulceration which may be accompanied by inguinal lymphadenitis or bubo formation. H ducreyi is a fastidious organism which is difficult to culture from genital ulcer material. DNA amplification techniques have shown improved diagnostic sensitivity but are only performed in a few laboratories. The management of chancroid in the tropics tends to be undertaken in the context of syndromic management of genital ulcer disease and treatment is usually with erythromycin. A number of single dose regimens are also available to treat H ducreyi infection. Genital ulceration as a syndrome has been associated with increased transmission of human immunodeficiency virus (HIV) infection in several cross sectional and longitudinal studies. Effective and early treatment of genital ulceration is therefore an important part of any strategy to control the spread of HIV infection in tropical countries.

Immunization with the N-terminal portion of Treponema pallidum repeat protein K attenuates syphilitic lesion development in the rabbit model

When used as an immunogen, Treponema pallidum repeat protein K (TprK) has been shown to attenuate syphilitic lesions upon homologous intradermal challenge in the rabbit model. To further explore this protein as a potential vaccine component, we sought to identify the immunogenic regions of TprK. The abilities of three recombinant peptides encompassing TprK to elicit T- and B-cell responses and to protect against challenge were examined. All three fragments elicited proliferative responses from splenocytes taken from infected rabbits. However, enzyme-linked immunosorbent assays indicated that only fragments 1 and 3 were consistently recognized by antisera from infected rabbits. Each fragment was also used to immunize rabbits that were subsequently challenged intradermally with infectious T. pallidum. All lesions on unimmunized control rabbits ulcerated and contained treponemes, while the lesions on rabbits immunized with fragment 1 were the least likely to have detectable treponemes (25%) and the least likely to ulcerate (37.5%). The lesions on rabbits immunized with fragment 3 showed intermediate results, and rabbits immunized with fragment 2 were the most likely of all those on immunized rabbits to have detectable treponemes (91.7%) and to ulcerate (66.7%). These results demonstrate that epitopes in fragment 1 are recognized by T cells and antibodies during infection and that immunization with this portion of TprK most effectively attenuates syphilitic lesion development.

A systematic review of the epidemiologic interactions between classic sexually transmitted diseases and HIV: how much really is known?

BACKGROUND

Many studies have explored the role of "classic" sexually transmitted diseases (STDs) in determining the pattern of HIV epidemics. However, the many different STDs may contribute in different ways, at different magnitudes.

GOAL

To review available studies on the bidirectional interactions of HIV and STDs to explore the extent of current knowledge on the different influences of the varied STDs in heterosexual HIV epidemics.

METHODS

Longitudinal studies on susceptibility and controlled studies on infectiousness and duration of disease identified on electronic databases through reference lists and citation indices up to the end of 1999 were systematically reviewed, including meta-analyses assessing the influence of STDs on susceptibility to HIV.

RESULTS

Studies have a clear publication bias with a significant result that hinders robust interpretation. However, genital ulcerative disease appears to have a greater impact than nonulcerative disease, and men are more affected than women by the effects of STDs on susceptibility to HIV. There is evidence that STDs increase the infectiousness of HIV from men to women, whereas the evidence is more equivocal for the infectiousness of women. Few studies identify the impact of different STDs, and there is a marked lack of studies investigating the impact of HIV infection on the transmission of other STDs.

CONCLUSIONS

A large body of work has measured the association between STDs and HIV. However, publication bias and gaps in the focus of studies mean that a detailed, quantitative understanding of the interaction requires much more attention.

An overview of sexually transmitted diseases. Part III. Sexually transmitted diseases in HIV-infected patients

The HIV epidemic has dramatically altered the field of sexually transmitted diseases (STDs). HIV infection is unique among sexually transmitted diseases because it can modify the clinical presentation and features of other STDs. Conversely, other STDs can affect the transmission of HIV. This review is the third part of a series that has provided a general overview of STDs. In this article, genital ulcer diseases (genital herpes, syphilis, chancroid, lymphogranuloma venereum, and granuloma inguinale), human papillomavirus infection (anogenital warts and subclinical infections), molluscum contagiosum, human herpesvirus 8 infection, viral hepatitis, and ectoparasitic infestations (scabies and pediculosis pubis) are discussed as they occur in HIV-infected hosts. Additional features as they relate to HIV-infected patients, such as epidemiology and transmission, are discussed when applicable.

LEARNING OBJECTIVE

At the conclusion of this learning activity, participants should improve their understanding of sexually transmitted diseases in the HIV-infected host.

Sexually transmitted diseases and the increased risk for HIV transmission: implications for cost-effectiveness analyses of sexually transmitted disease prevention interventions

We estimated the annual number and cost of new HIV infections in the United States attributable to other sexually transmitted diseases (STDs). We used a mathematical model of HIV transmission to estimate the probability that a given STD infection would facilitate HIV transmission from an HIV-infected person to his or her partner and to calculate the number of HIV infections due to these facilitative effects. In 1996, an estimated 5,052 new HIV cases were attributable to the four STDs considered here: chlamydia (3,249 cases), syphilis (1,002 cases), gonorrhea (430 cases), and genital herpes (371 cases). These new HIV cases account for approximately $985 million U.S. in direct HIV treatment costs. The model suggested that syphilis is far more likely than the other STDs (on a per-case basis) to facilitate HIV transmission. This analysis provides a framework for incorporating STD-attributable HIV treatment costs into cost-effectiveness analyses of STD prevention programs.

Development of a serological test for Haemophilus ducreyi for seroprevalence studies

We developed a new enzyme immunoassay (rpEIA) for use in determining the seroprevalence of chancroid. Three highly conserved outer membrane proteins from Haemophilus ducreyi strain 35000 were cloned, overexpressed, and purified from Escherichia coli for use as antigens in the rpEIA. Serum specimens from patients with and without chancroid were assayed to determine optimum sensitivity and specificity and to establish cutoff values. On the basis of these data, rpEIA was found to be both sensitive and specific when used to test a variety of serum specimens from patients with genital ulcers and urethritis and from healthy blood donors.

Geographic variation of HIV infection in childbearing women with syphilis in the United States

OBJECTIVES

Substantial biologic and epidemiologic data indicate the importance of syphilis as a potential cofactor for sexual transmission of HIV infection, but few detailed data exist on the geographic covariation of these two important sexually transmitted infections.

DESIGN

HIV prevalence in childbearing women and primary and secondary (P&S) syphilis data from 29 states were examined to explore the importance of the epidemiology of syphilis as a factor in facilitating HIV transmission.

METHOD

The spatial relationship between P&S syphilis and HIV infection in the health districts of 29 states was analyzed and adjusted for demographic and socioeconomic factors such as racial composition, income, housing, education levels, and access to medical services using the 1990 US census, and geographic location.

RESULTS

In 29 states and the District of Colombia, 448 health districts, representing more than 75% of the US population, reported HIV prevalence rates for mothers' district of residence. The HIV seroprevalence ranged from 0 to 1258/10 000 in these health districts. The incidence of P&S syphilis from 1984-1994 in these districts ranged from 0 to 87/100 000. The P&S syphilis incidence was positively associated with the prevalence of HIV infection among childbearing women (P < 0.0001).

CONCLUSIONS

Syphilis that persists in communities in the United States appears to represent a 'sentinel public health event' reflecting risk for sexual HIV transmission. These findings, along with other biologic and epidemiologic information, reinforce the importance of syphilis as an indicator for targeting HIV prevention efforts generally, as well as syphilis control as a specific HIV-prevention strategy.

Syphilis in Atlanta during an era of declining incidence

BACKGROUND

Syphilis transmission in Atlanta is ongoing despite declining incidence.

OBJECTIVES

To identify risk factors and missed opportunities for prevention.

STUDY DESIGN

A case-control study design was used. Twenty-five sexually transmitted disease (STD) clinic patients with primary or secondary syphilis by polymerase chain reaction and serology and 49 matched controls were interviewed.

RESULTS

Persons with syphilis more frequently had HIV infection (24% versus 2%; P = 0.005), crack-using sex partners (52% versus 18%; odds ratio [OR] = 5.1; 95% CI = 1.7-15.5), and a history of incarceration (80% versus 57%; OR = 3.0; CI = 1.0-9.3). Many cases (48%) and controls (31%) had received drug-abuse treatment. Only 40% of previously incarcerated patients and 74% of those with a history of drug treatment reported receiving STD/HIV education in those settings. Among all patients reporting recent HIV education, 41% were told about STD recognition and treatment. Unprotected sex and delay in seeking care were common.

CONCLUSION

To prevent syphilis and associated HIV, more extensive STD education is needed in jails and drug-treatment centers.

The Diagnosis and Management of Syphilis in the HIV-Infected Patient

In the 1980s, the number of cases of syphilis in the United States increased concurrently with the onset of the HIV epidemic. Within a short time, clinicians began to note unusual presentations of syphilis and inappropriate responses to standard therapy for syphilis in dually infected patients. Whether these cases collectively represented a new aspect of the natural history of syphilis remains to be elucidated. In recent years, only a few prospective studies have addressed this issue, and the results of these studies have been inconclusive.

Evidence of declining STD prevalence in a South African mining community following a core-group intervention

OBJECTIVES

To reduce the prevalence of curable sexually transmitted diseases (STDs) in a South African mining community through provision of STD treatment services, including periodic presumptive treatment and prevention education to a core group of high-risk women living in areas around the mines.

METHODS

Women at high risk for STDs attended a mobile clinic monthly for examination and counseling, and were treated presumptively for bacterial STDs with a directly observed 1-g dose of azithromycin. Gonococcal and chlamydial infection rates were measured by urine ligase chain reaction, and genital ulcers were assessed by clinical examination. Changes in STD prevalence among local miners were assessed through comparison of prevalence in two cross-sectional samples of miners taken 9 months apart, and through routine disease surveillance at mine health facilities.

RESULTS

During the first 9 months of the intervention, 407 women used the services. Baseline prevalence of Neisseria gonorrhoeae and/or Chlamydia trachomatis in women was 24.9%; 9.7% of these women had clinical evidence of genital ulcer disease (GUD). The proportion of women with incident gonococcal or chlamydial infections at the first monthly return visit (69% follow-up rate) was 12.3%, and genital ulcers were found in 4.4% of these women. In the miner population, the prevalence of N gonorrhoeae and/or C trachomatis was 10.9% at baseline and 6.2% at the 9-month follow-up examination (P<0.001). The prevalence of GUD by clinical examination was 5.8% at baseline and 1.3% at follow-up examination (P< 0.001). Rates of symptomatic STDs seen at mine health facilities decreased among miners in the intervention area compared with miners living farther from the site and with less exposure to the project.

DISCUSSION

Provision of STD treatment services to a core group of high-risk women may significantly reduce their burden of disease, and may contribute to a reduction in community STD prevalence. In the absence of sensitive and affordable screening tests for STDs in women, periodic presumptive treatment coupled with prevention education is a feasible approach to providing STD services in this population.

HIV prevalence in patients with syphilis, United States

BACKGROUND

Among persons with a sexually transmitted disease (STD), the proportion who are also infected with HIV is a major factor influencing the public health impact of that STD on HIV transmission.

GOAL

To assess HIV infection in persons with syphilis in the United States.

STUDY DESIGN

A systematic literature review was conducted of U.S. studies with HIV seroprevalence data in patients with syphilis.

RESULTS

Thirty studies were identified and analyzed. The median HIV seroprevalence in men and women infected with syphilis was 15.7% (interquartile range [IQR]: 13.6-21.8%), among men was 27.5% (23.1-29.6%), and among women was 12.4% (8.3-20.5%). Median odds ratios for men and women, men only, and women only were 4.5, 8.5, and 3.3, respectively. Seroprevalences among men who have sex with men (MSM) and injecting drug users (IDU) ranged from 64.3-90.0% and 22.5-70.6%, respectively.

CONCLUSIONS

Despite substantial variability, HIV seroprevalence is high among patients with syphilis in the United States, identifying them as a critical target group for HIV prevention efforts.

Chancroid: from clinical practice to basic science

Chancroid is a sexually transmitted disease caused by the bacterium Haemophilus ducreyi. It usually presents as a genital ulcer and may be associated with regional lymphadenopathy and bubo formation. H. ducreyi infection is predominantly seen in tropical resource-poor regions of the world where it is frequently the most common etiological cause of genital ulceration. Genital ulcer disease has been shown to be an extremely important co-factor in HIV transmission. With the advent of the AIDS epidemic, there has been increased research effort to elucidate those factors involved in the pathogenesis of chancroid. Several putative virulence factors have now been identified and isogenic H. ducreyi mutants constructed by mutagenesis of their encoding genes. This approach has facilitated investigations into the role each of these putative virulence factors may play in H. ducreyi pathogenesis through the use of in vitro and in vivo model systems. One major goal of current chancroid research is to identify antigens which are immunogenic and could form the basis of a vaccine against H. ducreyi infection. Such a vaccine, if shown to be effective in decreasing the prevalence of chancroid, could have the added benefit of slowing down the HIV incidence rates in those populations where chancroid is a major co-factor for HIV transmission.

From epidemiological synergy to public health policy and practice: the contribution of other sexually transmitted diseases to sexual transmission of HIV infection

OBJECTIVES

To review the scientific data on the role of sexually transmitted diseases (STDs) in sexual transmission of HIV infection and discuss the implications of these findings for HIV and STD prevention policy and practice.

METHODS

Articles were selected from a review of Medline, accessed with the OVID search engine. The search covered articles from January 1987 to September 1998 and yielded 2101 articles. Methods used to uncover articles which might have been missed included searching for related articles by author, and combing literature reviews. In addition, all abstracts under the category "sexually transmitted diseases" from the XI and XII International Conferences on AIDS (Vancouver 1996 and Geneva 1998) and other relevant scientific meetings were reviewed. Efforts were made to locate journal articles which resulted from the research reported in the identified abstracts. All original journal articles and abstracts which met one of the following criteria were included: (1) studies of the biological plausibility or mechanism of facilitation of HIV infectiousness or susceptibility by STDs, (2) prospective cohort studies (longitudinal or nested case-control) which estimate the risk of HIV infection associated with specific STDs or STD syndromes, or (3) intervention studies which quantitate the effect which STD treatment can have on HIV incidence.

RESULTS

Strong evidence indicates that both ulcerative and non-ulcerative STDs promote HIV transmission by augmenting HIV infectiousness and HIV susceptibility via a variety of biological mechanisms. These effects are reflected in the risk estimates found in numerous prospective studies from four continents which range from 2.0 to 23.5, with most clustering between 2 and 5. The relative importance of ulcerative and non-ulcerative STDs appears to be complex. Owing to the greater frequency of non-ulcerative STDs in many populations, these infections may be responsible for more HIV transmission than genital ulcers. However, the limited reciprocal impact of HIV infection on non-ulcerative STDs and the evidence that non-ulcerative STDs may increase risk primarily for the receptive partner (rather than bidirectionally) may modulate the impact of these diseases. The results of two community level randomised, controlled intervention trials conducted in Africa suggest that timely provision of STD services can substantially reduce HIV incidence, but raise additional questions about the optimal way to target and implement these services to achieve the greatest effect on HIV transmission.

CONCLUSIONS

Available data leave little doubt that other STDs facilitate HIV transmission through direct, biological mechanisms and that early STD treatment should be part of a high quality, comprehensive HIV prevention strategy. Policy makers, HIV prevention programme managers, and providers should focus initial implementation efforts on three key areas: (i) improving access to and quality of STD clinical services; (ii) promoting early and effective STD related healthcare behaviours; and (iii) establishing surveillance systems to monitor STD and HIV trends and their interrelations.

Sexually transmitted diseases in HIV-positive patients

The complex interaction between sexually transmitted diseases (STDs) and HIV has been demonstrated in many epidemiological studies and clinical trials over the last number of years. Herpes simplex virus, human papilloma virus, and syphilis are all accepted to have different manifestations, effects, and therapeutic responses in HIV positive patients. These and other issues are discussed in this article.

Cloning and characterization of tdhA, a locus encoding a TonB-dependent heme receptor from Haemophilus ducreyi

Haemophilus ducreyi is unable to synthesize heme and must acquire it from its only known host, humans. We cloned and sequenced a gene encoding an outer membrane receptor for heme. It was designated tdhA (for TonB-dependent heme receptor A) since it was related by sequence homology to the family of TonB-dependent receptors. TdhA was strikingly similar to open reading frame HI0113 from the genome of Haemophilus influenzae Rd and also shared homology with five other heme receptors, including HxuC, HemR, HmuR, ChuA, and ShuA, from gram-negative bacteria. An Escherichia coli hemA tonB mutant strongly expressing H. ducreyi tdhA grew on low levels of heme as a source of heme only when an intact H. ducreyi Ton system plasmid was present, formally demonstrating functional TonB dependence. tdhA was expressed poorly in vitro by H. ducreyi and only under conditions of heme limitation. A survey of H. ducreyi revealed that all tested strains but one synthesized small amounts of TdhA in vitro under heme-limiting conditions. Surprisingly, an isogenic mutant of tdhA as well as its parent, 35000, both required the same high levels of heme for growth (50 microgram/ml [77 microM] on agar medium). This result, together with previous findings, suggests that in vitro, the uptake of heme by H. ducreyi is mediated by a TonB- and TdhA-independent mechanism, possibly diffusion.

HIV-1 DNA shedding in genital ulcers and its associated risk factors in Pune, India

HIV infection status was determined in 302 consecutive patients with genital ulcer disease (GUD) presenting to two sexually transmitted disease (STD) clinics in Pune, India. Of the 71 (24%) individuals with HIV infection, 67 (94%) were HIV antibody-positive, and 4 (6%) were HIV antibody-negative but p24 antigen-positive at the time of presentation. HIV-1 DNA was detected in 24 (34%) specimens. The genital ulcers of all four acutely infected p24-antigenemic subjects were HIV-1 DNA-positive by polymerase chain reaction (PCR) assay, compared with 20 of 67 (30%) seropositive patients (p = .01). Presence of chancroid, GUD symptoms for > 10 days, and concurrent diagnosis of cervicitis or urethritis were significantly associated risk factors for HIV-1 DNA shedding in ulcers. Early GUD diagnosis and aggressive treatment of HIV-infected patients may significantly reduce secondary transmission of HIV to other sex partners.

Herpes simplex virus-2 infection. An emerging disease?

Genital herpes infections continue to increase in the world. As outlined previously, several factors play a role in the continued transmission of genital herpes worldwide. Reducing the medical consequences of HSV-2 infection will not be easy. It is also sobering to realize that widespread penetration of HSV-2 into the population had preceded the spread of sexually acquired HIV in most countries. The biological rationale for a connection between HIV and HSV continues to be strengthened. Currently, a specific program to decrease the transmission of genital herpes does not exist. Recent studies with antiviral agents indicate the potential of these compounds to reduce shedding in HIV-negative and in HIV-positive persons and potentially may be useful in preventing some aspects of HSV transmission. Advances in laboratory techniques to assist in the diagnosis of genital herpes infections have added to our knowledge of the natural history and epidemiology of infection. Because of imperfect laboratory tests, negative results do not always indicate lack of infection; this has important public health implications. Large numbers of unrecognized symptomatic cases and frequent asymptomatic shedding are the likely source of continued genital HSV-2 transmission. Solutions for reducing the transmission of genital herpes range from simple, such as counseling patients regarding symptoms and signs of genital herpes and the frequency of subclinical shedding, to complex and expensive, such as screening high risk populations (e.g., STD clinic attendees) for HSV-2 infection. Chronic antiviral therapy may be indicated in HSV-2 seropositive persons without monogamous relationships as they are at risk to transmit HSV to multiple persons. The authors' aim in this review is to provoke discussion of such a control program and to raise the consciousness of the feasibility of instituting control measures for selected populations. We hope to elicit pilot programs designed to reduce the morbidity of this old but re-emerging infectious disease.

A diffusible cytotoxin of Haemophilus ducreyi

Little is known about the virulence mechanisms employed by Haemophilus ducreyi in the production of genital ulcers. This Gram-negative bacterium previously has been shown to produce a soluble cytotoxic activity that kills HeLa and HEp-2 cells. We have now identified a cluster of three H. ducreyi genes that encode this cytotoxic activity. The predicted proteins encoded by these genes are most similar to the products of the Escherichia coli cdtABC genes that comprise the cytolethal distending toxin (CDT) of this enteric pathogen. Eleven of 12 H. ducreyi strains were shown to possess this gene cluster and culture supernatants from these strains readily killed HeLa cells. The culture supernatant from a single strain of H. ducreyi that lacked these genes was unable to kill HeLa cells. When the H. ducreyi cdtABC gene cluster was cloned into E. coli, culture supernatant from the recombinant E. coli clone killed HeLa cells. A monoclonal antibody that neutralized this soluble cytotoxic activity of H. ducreyi was shown to bind to the H. ducreyi cdtC gene product. This soluble H. ducreyi cytotoxin may play a role in the development or persistence of the ulcerative lesions characteristic of chancroid.

A hemoglobin-binding outer membrane protein is involved in virulence expression by Haemophilus ducreyi in an animal model

Haemophilus ducreyi exhibits a requirement for exogenously supplied heme for aerobic growth in vitro. Nine of ten wild-type isolates of H. ducreyi were shown to contain a readily detectable hemoglobin-binding activity. Spontaneous hemoglobin-binding-negative mutants of two of these wild-type isolates lost the ability to express an outer membrane protein with an apparent molecular mass of approximately 100 kDa. Similarly, the single wild-type isolate that lacked the ability to bind hemoglobin also appeared to lack expression of this same 100-kDa protein. A monoclonal antibody (5A9) to this 100-kDa protein was used to identify a recombinant clone which possessed an H. ducreyi chromosomal fragment containing the gene encoding the 100-kDa protein; this protein was designated hemoglobin utilization protein A (HupA). Nucleotide sequence analysis of the hupA gene revealed that the predicted protein, with a calculated molecular mass of 108 kDa, was similar to TonB-dependent outer membrane proteins of other bacteria. Increasing the concentration of heme in the growth medium resulted in decreased expression of the HupA protein. Mutant analysis was used to prove that the HupA protein was essential for the utilization by H. ducreyi of both hemoglobin and hemoglobin-haptoglobin as sources of heme in vitro. In addition, it was found that an isogenic hupA mutant was less virulent than the wild-type parent strain in the temperature-dependent rabbit model for dermal lesion production by H. ducreyi.

Detection of Haemophilus ducreyi lipooligosaccharide by means of an immunolimulus assay

A murine monoclonal antibody (MAb) directed against a surface-exposed epitope of the lipooligosaccharide (LOS) of Haemophilus ducreyi strain 35000 was shown to be reactive with all 37 strains of this pathogen tested in a colony blot-radioimmunoassay. The LOS epitope bound by this MAb appeared to be stably expressed by H. ducreyi growing in vitro. The use of this MAb in the immunolimulus system revealed that it could detect purified H. ducreyi LOS at a level of 25 pg/ml. Similarly, this immunolimulus system could detect as few as 1000 colony forming units of in vitro-grown H. ducreyi cells per ml of buffer. When this MAb was utilized in the immunolimulus system together with lesion material from rabbits infected with two different H. ducreyi strains, a positive reaction was obtained with every sample tested, even when no viable organisms were present in the lesion material. In contrast, this MAb yielded consistently negative results when used in the immunolimulus system with lesion material from animals infected with Staphylococcus aureus.

A system for generalized mutagenesis of Haemophilus ducreyi

The lack of a generalized mutagenesis system for Haemophilus ducreyi has hampered efforts to identify virulence factors expressed by this sexually transmitted pathogen. To address this issue, the transposable element Tn1545-delta 3, which encodes resistance to kanamycin, was evaluated for its ability to insert randomly into the H. ducreyi chromosome and produce stable, isogenic mutants. Electroporation of H. ducreyi with 1 microgram of plasmid pMS1 carrying Tn1545-delta 3 resulted in the production of 10(4) kanamycin-resistant transformants; Southern blot analysis of a number of these transformants indicated that insertion of the transposon into the chromosome occurred at a number of different sites. This pMS1-based transposon delivery system was used to produce an H. ducreyi mutant that expressed an altered lipooligosaccharide (LOS). Passage of this mutant in vitro in the presence or absence of kanamycin did not affect the stability of the transposon insertion. To confirm that the observed mutant phenotype was the result of the transposon insertion, a chromosomal fragment containing Tn1545-delta 3 was cloned from this H. ducreyi LOS mutant. Electroporation of the wild-type H. ducreyi strain with this DNA fragment yielded numerous kanamycin-resistant transformants, the majority of which had the same altered LOS phenotype as the original mutant. Southern blot analysis confirmed the occurrence of proper allelic exchange in the LOS-deficient transformants obtained in this backcross experiment. The ability of Tn1545-delta 3 to produce insertion mutations in H. ducreyi should facilitate genetic analysis of this pathogen.

Chancroid and Haemophilus ducreyi: an update

Haemophilus ducreyi is a fastidious gram-negative bacillus that causes the sexually transmitted infection chancroid. Chancroid is a major genital ulcerative disease in Africa, Southeast Asia, the Caribbean, and Latin America and is of increasing concern in the United States. Genital ulcerative disease and chancroid in particular have been associated with facilitating the transmission of human immunodeficiency virus. The diagnosis of chancroid based on the clinical appearance of the genital lesion or on the isolation of H. ducreyi on selective medium is relatively insensitive. However, recent advances in nonculture diagnostic tests have enhanced our ability to diagnose chancroid. There has been renewed interest in understanding the pathogenesis of H. ducreyi. In vitro and in vivo models have been developed to help identify important virulence determinants. Through the use of biochemical and molecular techniques, macromolecular components that may be important in virulence have been identified.

Genital ulcer disease in women infected with human immunodeficiency virus

OBJECTIVE

The purpose of this study was to determine the prevalence and microbiologic characteristics of genital ulcer disease in a population of human immunodeficiency virus-infected women.

STUDY DESIGN

A retrospective cohort study was performed in university-affiliated, hospital-based women's human immunodeficiency virus clinics. A total of 307 women with human immunodeficiency virus infection were followed up during 20 months. There were no interventions. Age, race, CD4+ cell counts, bacteriologic and virologic analyses in cases of ulcers, serologic testing for syphilis, and histopathologic examination in selected cases (n = 6).

RESULTS

Among 307 women followed up over a 20-month period, 43 ulcers were detected with a prevalence of 14%. Among the ulcer cases the average absolute CD4+ lymphocyte number was 210/mm3. Diagnostic evaluation yielded no proven etiologic agent in 26 (60%) of the cases. Twelve of the 43 cases (28%) were positive for herpes simplex-2. Five cases (12%) yielded unusual or mixed bacteriologic types. No cases were attributable to primary syphilis infection. One case each of an ulcer infected with cytomegalovirus, Chlamydia trachomatis, and Gardnerella vaginalis, as well as three unusual presentations of herpetic ulcers, is analyzed in detail.

CONCLUSION

These cases exemplify the often dramatic presentation of human immunodeficiency virus-related genital ulcers and the clinical complexity of both diagnosis and management. The frequent lack of an infectious or neoplastic cause in human immunodeficiency virus-infected women with genital ulcer disease suggests that human immunodeficiency virus may play a local role in causation or exacerbation. Biopsies of atypical genital ulcers should be considered to aid diagnosis. Further studies are needed to elucidate the pathogenesis of genital ulcer disease in human immunodeficiency virus-infected women.

Ceftriaxone in the treatment of chronic donovanosis in central Australia

OBJECTIVES

To determine the effectiveness of intramuscular (IM) ceftriaxone sodium in the treatment of chronic donovanosis, and the acceptability to patients and staff of supervised outpatient treatment in rural clinics.

METHODS

We collected demographic and sexual health data from participants using a standard questionnaire, and recorded their donovanosis lesions at baseline using genital diagrams. Treatment consisted of a single daily IM injection of 1 g ceftriaxone diluted in 2 ml of 1% lignocaine. Clinic staff followed patients for between three and 12 months, enabling the detection of late recurrences.

SETTING

Rural Aboriginal communities in central Australia.

PARTICIPANTS

The study describes eight women and four men with chronic donovanosis in detail, and summarises the outcome in 12 additional cases. All cases presented with advanced lesions which had failed to heal on the standard oral antibiotic regimens used in the region.

RESULTS

The mean duration of infection was 3.0 years (SD 1.9 years), and between four and ten courses of antibiotics had been prescribed for six of the 12 patients. Patients received between 7-26g of ceftriaxone sodium. Clinical improvement was dramatic in most lesions, and four patients healed completely without recurrence after a total 7-10g of ceftriaxone. Mild recurrences responded to further ceftriaxone or short courses of oral antibiotics. Treatment was well tolerated, and both patient and staff compliance high.

CONCLUSION

Donovanosis is an important cause of chronic genital ulceration in central Australia, and is potentially an important risk factor for HIV transmission in Aboriginal communities. The pharmacokinetics and safety profile of ceftriaxone make it a useful and cost-effective agent in the ambulatory management of donovanosis, especially in remote communities. Supervised multidrug regimens of two or more long-acting agents may provide the best answer in donovanosis, administered through the existing health care infrastructure.

Human ecology and behavior and sexually transmitted bacterial infections

The three direct determinants of the rate of spread of sexually transmitted diseases (STDs) are sexual behaviors, the mean duration of infectiousness, and the mean efficiency of sexual transmission of each STD. Underlying ecological and behavioral factors that operate through one or more of these direct determinants lie on a continuum, ranging from those most proximate back to those more remote (in time or mechanism) from the direct determinants. Most remote and least modifiable are the historical stages of economic development that even today conspicuously influence patterns of sexual behavior. Next are the distribution and changing patterns of climate, hygiene, and population density; the global population explosion and stages of the demographic transition; and ongoing changes in human physiology (e.g., menarche at younger age) and culture (e.g., later marriage). More proximate on the continuum are war, migration, and travel; and current policies for economic development and social welfare. Most recent or modifiable are technologic and commercial product development (e.g., oral contraceptives); circumcision, condom, spermicide, and contraception practices; patterns of illicit drug use that influence sexual behaviors; and the accessibility, quality, and use of STD health care. These underlying factors help explain why the curable bacterial STDs are epidemic in developing countries and why the United States is the only industrialized country that has failed to control bacterial STDs during the AIDS era.

The polymerase chain reaction: a new tool for the understanding and diagnosis of HIV-1 infection at the molecular level

The polymerase chain reaction (PCR) is at present the most powerful analytical tool for detection of specific nucleic acid sequences. The method is based on the in vitro amplification of DNA segments before detection with conventional hybridization techniques or visualization following electrophoresis and staining. The current diagnostic methods for HIV-1 do not allow easy identification of subgroups of infected patients including infants born to seropositive mothers, individuals with delayed serological responses to the virus, infected patients with indeterminate serology results, and patients with dual retroviral infections. Furthermore, response to antiviral therapy cannot be evaluated with serological assays. The rationale for applying PCR in those situations is elaborated here. The applications of this technique for HIV-1 as a diagnostic test and for the understanding of the pathogenesis of this retrovirus are described. Potential limitations of this technique for diagnostic purposes include mainly the possibility of false-positive results due to contamination and false-negative reactions caused by Taq polymerase inhibition. Non-isotopic means for detection of amplified products have been described and should allow for a wider application of this technology. Modifications of PCR which make use of internal standards seem promising for quantitative analysis of nucleic acids. PCR has great potential for viral diagnosis but still requires further studies and better characterization.