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Stanley M Spinola - One of the best experts on this subject based on the ideXlab platform.

  • experimental infection with haemophilus ducreyi in persons who are infected with hiv does not cause local or augment systemic viral replication
    The Journal of Infectious Diseases, 2007
    Co-Authors: Diane M. Janowicz, Kate R Fortney, Barry P. Katz, Tricia L. Humphreys, Klara Tennerracz, Paul Racz, Carol T Schnizleinbick, Beth Zwickl, James J Campbell, Stanley M Spinola
    Abstract:

    Haemophilus ducreyi causes the genital ulcer disease (GUD) Chancroid. Chancroid remains prevalent in developing countries, where HIV infection is endemic [1], and facilitates HIV acquisition and transmission [1, 2]. HIV RNA level, or viral load (VL), in the urogenital compartment or its surrogate, plasma VL, is the major predictor of the sexual transmission of HIV [3]. VL is highest during acute HIV infection, during the late stages of AIDS, and during coinfections with other sexually transmitted pathogens [3]. Chancroid is estimated to increase the risk of HIV acquisition by 25-fold [4]. Simulation models estimate that ~80%–90% of the HIV infections that occurred during the first decade of the pandemic in sub-Saharan Africa were mostly attributable to ulcerative sexually transmitted diseases [4, 5]. Men with HIV infection, nongonococcal urethritis (NGU), and GUD in a country in which Chancroid is endemic have increased semen VLs versus men with NGU but no GUD, and semen VLs are reduced with appropriate antibiotic therapy for NGU and GUD [6]. However, no prospective studies have examined the effect of Chancroid on VL. To study the biology of H. ducreyi, we developed a model in which bacteria are delivered to the skin of the upper arms of healthy adult volunteers by puncture wound [7]. Experimental infection closely mimics the initial stages and histopathology of natural Chancroid [7–12]. In the human infection model, H. ducreyi colocalizes with polymorphonuclear neutrophils (PMNs), macrophages, and fibrin [13]; remains extracellular; and evades phagocytosis [14]. These relationships are maintained in natural ulcers [15]. Although atypical presentations of Chancroid in HIV-infected persons were initially reported [16, 17], subsequent studies have shown little difference in the clinical course and response to antibiotics between HIV-infected and HIV-seronegativepersons [18–20]. The histopathology of Chancroid in HIV-infected and HIV-seronegative persons is similar [11, 21]. We reasoned that experimental infection of HIV-infected volunteers would be safe because the organism is extracellular and impaired T cell–mediated immunity should not have a major effect on the course of experimental infection. Here, we studied interactions between H. ducreyi and HIV by experimentally infecting HIV-infected volunteers with H. ducreyi. We hypothesized that the clinical course and lesional infiltrate in HIV-infected persons would be similar to that seen in HIV-seronegative persons. Because experimental infection in HIV-seronegative persons does not cause systemic immune responses [8], we hypothesized that experimental infection would not lead to sustained increases in HIV replication or the lowering of CD4+ cell counts in the systemic compartment. We also hypothesized that experimental infection would recruit latently infected CD45RO+CD4+ cells and macrophages to the skin, activate these cells, and cause them to produce virus locally in treatment-naive subjects but not in subjects receiving highly active antiretroviral therapy (HAART). This is the first study to prospectively examine the effect of Chancroid on HIV replication and CD4+ cell count, albeit in an experimental setting.

  • localization of haemophilus ducreyi in naturally acquired Chancroidal ulcers
    Microbes and Infection, 2006
    Co-Authors: Margaret E. Bauer, Allan R. Ronald, Stanley M Spinola, Carisa A Townsend
    Abstract:

    Haemophilus ducreyi causes the sexually transmitted genital ulcer disease Chancroid. In human inoculation experiments, bacteria colocalize with neutrophils and macrophages but remain extracellular. The organism also colocalizes with collagen and fibrin but not with keratinocytes, fibroblasts, laminin, or fibronectin. These relationships are established by 48 h postinoculation and persist through the pustular stage of disease. To extend these observations to the ulcerative stage of disease, and to compare results in the human model with those of natural disease, we obtained biopsies from patients with naturally acquired Chancroid. All ulcers were culture positive for H. ducreyi and histologically very similar to pustules from the human model. Staining with H. ducreyi-specific monoclonal antibodies demonstrated H. ducreyi within 5 biopsies. The organism was chiefly found within the granulocytic infiltrate of the ulcer. Dual staining for H. ducreyi and eukaryotic tissue components showed that H. ducreyi colocalized with neutrophils and fibrin at the ulcerative stage of disease. No bacteria were associated with keratinocytes, fibroblasts, or collagen. Overall, these findings are consistent with results from the human model. This is the first reported study to localize bacteria specifically identified as H. ducreyi within naturally acquired Chancroid.

  • Immunopathogenesis of Haemophilus ducreyi Infection (Chancroid)
    Infection and Immunity, 2002
    Co-Authors: Stanley M Spinola, Margaret E. Bauer, Robert S. Munson
    Abstract:

    Haemophilus ducreyi causes Chancroid, a genital ulcer disease (GUD) that is common in many developing countries ([13][1], [14][2], [26][3], [68][4], [80][5], [103][6]). UNAIDS and the World Health Organization estimate that the annual global incidence of Chancroid is approximately 6 million cases ([

  • Men are more susceptible than women to pustule formation in the experimental model of Haemophilus ducreyi infection.
    Sexually Transmitted Diseases, 2002
    Co-Authors: Cliffton T.h. Bong, Barry P. Katz, Jaroslaw Harezlak, Stanley M Spinola
    Abstract:

    Background Naturally occurring Chancroid is usually more prevalent in men than in women. Goal To examine whether there were gender differences in susceptibility to Haemophilus ducreyi infection by analyzing the papule and pustule formation rates for men and women who were experimentally inoculated with Haemophilus ducreyi. Study Design Ninety volunteers were included in the analysis. A total of 189 sites were available for estimation of the papule formation rate, and 166 sites for estimation of the pustule formation rates using logistic regression modeling. Results Although there were no gender differences in papule formation rates, the women had significantly lower rates of pustule formation than the men after adjustment for the estimated delivered dose. Conclusions In women the disease will resolve and not progress to the pustular stage of disease as often as in men. The high male-to-female ratio in naturally occurring Chancroid may in part reflect biological differences in gender susceptibility to disease progression, although the mechanisms responsible for this difference are unclear.

  • haemophilus ducreyi is susceptible to protegrin
    Antimicrobial Agents and Chemotherapy, 1998
    Co-Authors: Kate R Fortney, Robert I Lehrer, Patricia A. Totten, Stanley M Spinola
    Abstract:

    Protegrins, potent antimicrobial peptides found in porcine leukocytes, have activity against the sexually transmitted pathogens Neisseria gonorrhoeae , Chlamydia trachomatis , and human immunodeficiency virus type 1. We tested synthetic protegrin 1 (PG-1) for activity against nine isolates of Haemophilus ducreyi , the etiologic agent of Chancroid. The test organisms included CIP 542 (the type strain), 35000HP (a human-passaged variant of 35000), 35000HP-RSM2 (an isogenicd- glycero -d- manno -heptosyltransferase mutant of 35000HP), and six clinical isolates. The isolates were epidemiologically unrelated, represented three Hin dIII ribotypes, and had varying antimicrobial resistance patterns. In bactericidal assays, five isolates were rapidly killed by synthetic PG-1. In radial diffusion assays, all nine isolates were exquisitely sensitive to PG-1. These data highlight the potential of protegrins for development as topical agents to prevent many sexually transmitted diseases, including Chancroid.

Francis A. Plummer - One of the best experts on this subject based on the ideXlab platform.

  • Genitourin Med 1988;64:189-92 Treating Chancroid with enoxacin
    2016
    Co-Authors: W Naamara, H Nsanze, D Y Kunimoto, Jo Ndinya-achola, Lourdes J D&apos, Allan T R Ronald, Francis A. Plummer
    Abstract:

    SUMMARY Increasing resistance of Haemophilus ducreyi to antimicrobials necessitates further trials ofnew antimicrobial agents for treating Chancroid. Enoxacin has excellent in vitro activity against H ducreyi, and a randomised clinical trial of three doses of enoxacin 400 mg at intervals of 12 hours compared with a single dose oftrimethoprim/sulphametrole (TMP/SMT) 640/3200 mg was therefore conducted. Of 169 men enrolled in the study, 86 received enoxacin and 83 received TMP/SMT. Ulcers were improved or cured in 65/73 men treated with enoxacin and 57/70 men treated with TMP/SMT. This difference was not significant. At 72 hours after treatment, Hducryei was eradicated from ulcers of 72/77 men treated with enoxacin and of 67/74 of those treated with TMP/SMT. Patients with buboes responded equally well to both treatments. Of 100 Hducreyi strains tested, all were susceptible to both 0.25 mg/l enoxacin and the combination of 0.25 mg/l TMP and 5 mg/l SMT. Although most men treated with either regimen were cured, neither regimen appeared to be the optimum treatment for Chancroid. This study shows the efficacy of enoxacin for a soft tissue infection caused by Gram negative organisms. Haemophilus ducreyi is the most common cause of genital ulcers in both men and women in Kenya.'2 It is endemic throughout the tropics. Chancroid is not a problem exclusive to developing countries, however, as witnessed by the recent epidemic on Orang

  • Treating Chancroid with enoxacin
    2016
    Co-Authors: Allan Ronald, H Nsanze, W Naamara, D Y Kunimoto, Jo Ndinya-achola, Frank Plummer, Lourdes J D&apos, Allan T R Ronald, Francis A. Plummer
    Abstract:

    SUMMARY Increasing resistance of Haemophilus ducreyi to antimicrobials necessitates further trials ofnew antimicrobial agents for treating Chancroid. Enoxacin has excellent in vitro activity against H ducreyi, and a randomised clinical trial of three doses of enoxacin 400 mg at intervals of 12 hours compared with a single dose oftrimethoprim/sulphametrole (TMP/SMT) 640/3200 mg was therefore conducted. Of 169 men enrolled in the study, 86 received enoxacin and 83 received TMP/SMT. Ulcers were improved or cured in 65/73 men treated with enoxacin and 57/70 men treated with TMP/SMT. This difference was not significant. At 72 hours after treatment, Hducryei was eradicated from ulcers of 72/77 men treated with enoxacin and of 67/74 of those treated with TMP/SMT. Patients with buboes responded equally well to both treatments. Of 100 Hducreyi strains tested, all were susceptible to both 0.25 mg/l enoxacin and the combination of 0.25 mg/l TMP and 5 mg/l SMT. Although most men treated with either regimen were cured, neither regimen appeared to be the optimum treatment for Chancroid. This study shows the efficacy of enoxacin for a soft tissue infection caused by Gram negative organisms. Haemophilus ducreyi is the most common cause of genital ulcers in both men and women in Kenya.'2 It i

  • a randomized double blind placebo controlled trial of single dose ciprofloxacin versus erythromycin for the treatment of Chancroid in nairobi kenya
    The Journal of Infectious Diseases, 1999
    Co-Authors: Isaac M Malonza, Francis A. Plummer, J O Ndinyaachola, Mark W Tyndall, Ian Maclean, Siad Omar, Kelly S Macdonald, Jos Perriens, Karina Anna Orle
    Abstract:

    A randomized, double-blind, placebo-controlled clinical trial was conducted in Nairobi, Kenya, to compare single-dose ciprofloxacin with a 7-day course of erythromycin for the treatment of Chancroid. In all, 208 men and 37 women presenting with genital ulcers clinically compatible with Chancroid were enrolled. Ulcer etiology was determined using culture techniques for Chancroid, serology for syphilis, and a multiplex polymerase chain reaction for Chancroid, syphilis, and herpes simplex virus (HSV). Ulcer etiology was 31% unmixed Chancroid, 23% unmixed syphilis, 16% unmixed HSV, 15% mixed etiology, and 15% unknown. For 111 participants with Chancroid, cure rates were 92% with ciprofloxacin and 91% with erythromycin. For all study participants, the treatment failure rate was 15%, mostly related to ulcer etiologies of HSV infection or syphilis, and treatment failure was 3 times more frequent in human immunodeficiency virus-infected subjects than in others, mostly owing to HSV infection. Ciprofloxacin is an effective single-dose treatment for Chancroid, but current recommendations for empiric therapy of genital ulcers may result in high treatment failure due to HSV infection.

  • presumptive specific clinical diagnosis of genital ulcer disease gud in a primary health care setting in nairobi
    International Journal of Std & Aids, 1996
    Co-Authors: J O Ndinyaachola, Francis A. Plummer, A R Ronald, A N Kihara, Lloyd D Fisher, Melissa R Krone, King K Holmes
    Abstract:

    During a 12-month period in 1990-1991 in Kenya 1076 of 22274 patients (4.8% of all patients over 12 years of age) presented at the Langata Health Center in Nairobi with symptoms of a sexually transmitted disease (STD). Researchers analyzed data on 980 of these patients whose records had complete data to assess the use of presumptive specific clinical diagnosis in the management of STDs in a primary health clinic. 17.1% (168) had genital ulcer disease (GUD). Men were more likely to have a GUD than women (24.7% vs. 10.4%). Haemophilus ducreyi the etiologic agent of Chancroid was isolated in the cultures of 40% of the patients with a presumptive specific clinical diagnosis of Chancroid compared with 17% of those with a presumptive specific clinical diagnosis of syphilis herpes or lymphogranuloma venereum (LGV) (p = 0.02). The clinical diagnoses of these two GUDs had only a weak correlation with microbiological and serological diagnoses (p = 0.13). 24% of patients with a presumptive specific clinical diagnosis of syphilis 31% of those with a presumptive specific clinical diagnosis of Chancroid 6% of those with a specific clinical diagnosis of genital herpes or LGV and 4.7% of those who had no GUD disease tested positive for syphilis (p < 0.001 GUD vs. no GUD). Among patients with syndromic diagnosis of GUD the presumptive specific clinical diagnosis of Chancroid had a high sensitivity (91%) low specificity (24%) and low positive predictive value (40%). Among patients with syndromic diagnosis of syphilis the presumptive specific clinical diagnosis of syphilis had a low sensitivity (25%) higher specificity (87%) and low positive predictive value (24%). 13% of patients with positive cultures for H. ducreyi did not receive a recommended or effective drug for Chancroid. 82% of patients who tested positive for syphilis did not receive a recommended drug for syphilis. Based on these findings the researchers conclude that syndromic treatment of GUD with use of antimicrobial combinations active against both Chancroid and syphilis is a better course of treatment than use of single drugs based on presumptive specific clinical diagnoses for this population.

  • single dose azithromycin for the treatment of Chancroid a randomized comparison with erythromycin
    Sexually Transmitted Diseases, 1994
    Co-Authors: Mark W Tyndall, Francis A. Plummer, Elizabeth Agoki, William Malisa, J O Ndinyaachola, Allan R. Ronald
    Abstract:

    Background and objectives Chancroid is endemic in sub-Saharan Africa and enhances the sexual transmission of the human immunodeficiency virus Type 1 (HIV-1). Azithromycin is an orally absorbed macrolide antibiotic that is active against Haemophilus ducreyi, the causative agent of Chancroid, and has pharmacokinetic properties that are suitable for single dosing. Study design In a randomized single-blinded study of 127 men presenting to a referral STD clinic with culture proven Chancroid, we compared the efficacy of azithromycin, administered as a single 1 g dose, with erythromycin 500 mg given 4 times daily for 7 days. Results Cure rates were 89% (73 of 82) in the azithromycin group and 91% (41 of 45) in the erythromycin group. A failure to respond to treatment was associated with HIV-1 seropositivity and a lack of circumcision. Both regimens were well tolerated. Conclusions Azithromycin, given as a single 1 g oral dose, is an effective treatment for Chancroid in men, and offers major prescribing advantages over erythromycin.

David A Lewis - One of the best experts on this subject based on the ideXlab platform.

  • haemophilus ducreyi from sexually transmitted infection to skin ulcer pathogen
    Current Opinion in Infectious Diseases, 2016
    Co-Authors: David A Lewis, Oriol Mitja
    Abstract:

    Purpose of reviewThis article provides an overview of the biology, epidemiology, clinical features, diagnostic tests, and treatment of Haemophilus ducreyi infection, with special reference to the decline of Chancroid and the recent emergence of H. ducreyi as a pathogen responsible for chronic limb u

  • epidemiology clinical features diagnosis and treatment of haemophilus ducreyi a disappearing pathogen
    Expert Review of Anti-infective Therapy, 2014
    Co-Authors: David A Lewis
    Abstract:

    Chancroid, caused by Haemophilus ducreyi, has declined in importance as a sexually transmitted pathogen in most countries where it was previously endemic. The global prevalence of Chancroid is unknown as most countries lack the required laboratory diagnostic capacity and surveillance systems to determine this. H. ducreyi has recently emerged as a cause of chronic skin ulceration in some South Pacific islands. Although no antimicrobial susceptibility data for H. ducreyi have been published for two decades, it is still assumed that the infection will respond successfully to treatment with recommended cephalosporin, macrolide or fluoroquinolone-based regimens. HIV-1-infected patients require careful follow-up due to reports of treatment failure with single dose regimens. Buboes may need additional treatment with either aspiration or excision and drainage.

  • treatment of Chancroid in resource poor countries
    Expert Review of Anti-infective Therapy, 2005
    Co-Authors: Naa Torshie Annan, David A Lewis
    Abstract:

    Chancroid, formerly a major cause of the genital ulcer disease syndrome, remains an important cofactor in both the transmission and acquisition of HIV-1 infection. Those countries with the greatest burden of HIV also have some of the highest prevalence rates of Chancroid worldwide. The diagnosis of Chancroid, caused by the fastidious bacterium Haemophilus ducreyi, is both expensive and difficult in many resource-poor areas. These areas of the world use syndromic management to treat genital ulcers and such an approach has proven effective in reducing rates of bacterial genital ulcer diseases. There are currently inexpensive and effective single-dose therapies available to treat Chancroid. Single-dose regimens, given at first presentation, improve compliance and reduce the risk of sexually transmitted infections. Bacterial resistance to several antimicrobial agents has increased over the years and remains a continued threat to effective antimicrobial therapy. Follow-up of cases, and partner notification and...

  • Chancroid clinical manifestations diagnosis and management
    Sexually Transmitted Infections, 2003
    Co-Authors: David A Lewis
    Abstract:

    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.

  • diagnostic tests for Chancroid
    Sexually Transmitted Infections, 2000
    Co-Authors: David A Lewis
    Abstract:

    The identification of the causative agent of Chancroid, Haemophilus ducreyi , was first reported in 1889 by August Ducrey, as a short streptobacillary rod with rounded ends, following experiments in which he autoinoculated patients' forearms with pus from their genital ulcers.1 Bezancon et al subsequently inoculated the forearms of human volunteers with culture purified organisms and produced characteristic soft chancres from which the same organism was re-isolated.2 This observation definitively identified H ducreyi as the causative organism of Chancroid by fulfilling Koch's postulates. Chancroid is a major cause of genital ulcer disease (GUD) in many resource poor countries of Africa, Asia, and Latin America although it remains relatively uncommon in the United States and Western Europe.3, 4 Tender inguinal lymphadenopathy or bubo formation is a characteristic feature in up to 50% of Chancroid patients.5 Genital ulcers may caused by other sexually transmitted agents apart from H ducreyi , including Treponema pallidum , Chlamydia trachomatis serovars L1-L3, Calymmatobacterium granulomatis , and herpes simplex virus (HSV). It is therefore important to use appropriate diagnostic techniques in the management of patients presenting with the genital ulcer syndrome so that adequate treatment can be administered. In resource poor settings, where diagnostic facilities are not readily available, the World Health Organisation advocates the use of a syndromic management approach for the management of genital ulcer disease.6 Prospective and cross sectional case-control studies in Africa have provided substantial evidence that Chancroid, either as a constituent of the GUD syndrome or as an aetiological diagnosis, is a risk factor for the heterosexual spread of human immunodeficiency virus (HIV).7–9 The few clinical studies published to date suggest that HIV seropositive men have increased numbers of genital ulcers which are slow to heal10, 11 and there are reports …

Allan R. Ronald - One of the best experts on this subject based on the ideXlab platform.

  • localization of haemophilus ducreyi in naturally acquired Chancroidal ulcers
    Microbes and Infection, 2006
    Co-Authors: Margaret E. Bauer, Allan R. Ronald, Stanley M Spinola, Carisa A Townsend
    Abstract:

    Haemophilus ducreyi causes the sexually transmitted genital ulcer disease Chancroid. In human inoculation experiments, bacteria colocalize with neutrophils and macrophages but remain extracellular. The organism also colocalizes with collagen and fibrin but not with keratinocytes, fibroblasts, laminin, or fibronectin. These relationships are established by 48 h postinoculation and persist through the pustular stage of disease. To extend these observations to the ulcerative stage of disease, and to compare results in the human model with those of natural disease, we obtained biopsies from patients with naturally acquired Chancroid. All ulcers were culture positive for H. ducreyi and histologically very similar to pustules from the human model. Staining with H. ducreyi-specific monoclonal antibodies demonstrated H. ducreyi within 5 biopsies. The organism was chiefly found within the granulocytic infiltrate of the ulcer. Dual staining for H. ducreyi and eukaryotic tissue components showed that H. ducreyi colocalized with neutrophils and fibrin at the ulcerative stage of disease. No bacteria were associated with keratinocytes, fibroblasts, or collagen. Overall, these findings are consistent with results from the human model. This is the first reported study to localize bacteria specifically identified as H. ducreyi within naturally acquired Chancroid.

  • single dose azithromycin for the treatment of Chancroid a randomized comparison with erythromycin
    Sexually Transmitted Diseases, 1994
    Co-Authors: Mark W Tyndall, Francis A. Plummer, Elizabeth Agoki, William Malisa, J O Ndinyaachola, Allan R. Ronald
    Abstract:

    Background and objectives Chancroid is endemic in sub-Saharan Africa and enhances the sexual transmission of the human immunodeficiency virus Type 1 (HIV-1). Azithromycin is an orally absorbed macrolide antibiotic that is active against Haemophilus ducreyi, the causative agent of Chancroid, and has pharmacokinetic properties that are suitable for single dosing. Study design In a randomized single-blinded study of 127 men presenting to a referral STD clinic with culture proven Chancroid, we compared the efficacy of azithromycin, administered as a single 1 g dose, with erythromycin 500 mg given 4 times daily for 7 days. Results Cure rates were 89% (73 of 82) in the azithromycin group and 91% (41 of 45) in the erythromycin group. A failure to respond to treatment was associated with HIV-1 seropositivity and a lack of circumcision. Both regimens were well tolerated. Conclusions Azithromycin, given as a single 1 g oral dose, is an effective treatment for Chancroid in men, and offers major prescribing advantages over erythromycin.

  • fleroxacin in the treatment of Chancroid an open study in men seropositive or seronegative for the human immunodeficiency virus type 1
    The American Journal of Medicine, 1993
    Co-Authors: F A Plummer, J O Ndinyaachola, Mark W Tyndall, Pierre J Plourde, Elizabeth Agoki, William Malisa, Allan R. Ronald
    Abstract:

    Fleroxacin was prescribed to treat both HIV-negative and HIV-positive men with proven Chancroid in an open study. HIV-negative men were treated with a single 400-mg dose of fleroxacin, and HIV-positive men were treated with 400 mg daily for 5 days. Three of the 58 evaluable HIV-negative men were clinical and microbiologic failures, and two of the 22 evaluable HIV-positive men had persisting infection with Haemophilus ducreyi. Both regimens were well tolerated. Fleroxacin is an acceptable alternative to existing treatment regimens for Chancroid in men.

  • use of an adsorption enzyme immunoassay to evaluate the haemophilus ducreyi specific and cross reactive humoral immune response of humans
    Sexually Transmitted Diseases, 1992
    Co-Authors: Michelle Alfa, Nancy Olson, Pat Degagne, Leslie Slaney, Frank A Plummer, Warren Namaara, Allan R. Ronald
    Abstract:

    : Serodiagnosis of Chancroid is limited by the cross-reactivity of Haemophilus ducreyi with Haemophilus influenzae and Haemophilus parainfluenzae. This research describes an adsorption enzyme immunoassay (EIA) that assesses the humoral immune response of North Americans and Africans to H. ducreyi. Adsorption effectively removed anti-H. influenzae and anti-H. parainfluenzae antibodies, revealing that North American control sera had no residual anti-H. ducreyi reactivity. However, African control sera still had a residual anti-H. ducreyi response. Assessment of the duration of the humoral immune response in sera from African patients with Chancroid showed that the humoral antibodies persisted for up to 8 months after the diagnosis. This may explain the lack of specificity of the adsorption EIA in areas where Chancroid is endemic. The detection of the humoral immune response was affected by the strain of H. ducreyi used, with indigent strains being most useful. Using H. ducreyi 35000 for Canadian sera, the sensitivity of the adsorption EIA was 100% and the specificity was 88%. For African sera, H. ducreyi strain R018 was used, and the adsorption EIA had a sensitivity of 81% and a specificity of only 23%. These data reveal that the existing humoral response in a country where Chancroid is endemic differs from that in a country where it is not, and that care must be used interpreting unadsorbed humoral immune responses. The adsorption EIA approach may prove useful as an epidemiologic tool for definition of existing (past and present) levels of exposure to H. ducreyi.

  • a randomized double blind study of the efficacy of fleroxacin versus trimethoprim sulfamethoxazole in men with culture proven Chancroid
    The Journal of Infectious Diseases, 1992
    Co-Authors: Pierre J Plourde, Allan R. Ronald, J O Ndinyaachola, Elizabeth Agoki, Leslie Slaney, L J Dcosta, John Ombette, Francis A. Plummer
    Abstract:

    Chancroid is linked to the spread of human immunodeficiency virus type 1 (HIV-1) in East Africa. Effective, easily administered therapy is a priority for the control of Haemophilus ducreyi. The efficacy of a single oral dose of fleroxacin, 400 mg, was compared to a 3-day oral course of trimethoprim-sulfamethoxazole (TMP-SMZ), 160/800 mg, twice daily for the treatment of Chancroid in 98 HIV-1-seronegative men in Nairobi, Kenya. No differences were noted between the two groups with respect to demographic characteristics, sexual behavior, and clinical characteristics. Culture-proven failure occurred in 1 (3%) of 36 fleroxacin-treated patients and in 11 (30%) of 37 TMP-SMZ-treated patients (P = .005). Fleroxacin, as a single oral dose, is an effective treatment for culture-proven Chancroid in patients who are HIV-1 seronegative. TMP-SMZ is no longer predictably effective due to the recent emergence of resistance to both sulfonamides and to trimethoprim.

S A Morse - One of the best experts on this subject based on the ideXlab platform.

  • Chancroid primary syphilis genital herpes and lymphogranuloma venereum in antananarivo madagascar
    The Journal of Infectious Diseases, 1999
    Co-Authors: S A Morse, Frieda Behets, Jocelyne Andriamiadana, Daudet Randrianasolo, Rene Randriamanga, Desire Rasamilalao, Chengyen Chen, Judith B Weiss, Gina Dallabetta
    Abstract:

    Ulcer material from consecutive patients attending clinics in Antananarivo, Madagascar, was tested using multiplex polymerase chain reaction (M-PCR) to detect Treponema pallidum, Haemophilus ducreyi, and herpes simplex virus. Sera were tested for syphilis and for IgG and IgM antibodies to Chlamydia trachomatis by microimmunofluorescence testing (MIF). By M-PCR, 33% of 196 patients had Chancroid, 29% had syphilitic ulcers, and 10% had genital herpes; 32% of the ulcer specimens were M-PCR negative. Compared with M-PCR, syphilis serology was 72% sensitive and 83% specific. The sensitivity of clinical diagnosis of syphilis, Chancroid, and genital herpes was 93%, 53%, and 0% and specificity was 20%, 52%, and 99%, respectively. Less schooling was associated with increased prevalence of syphilitic ulcers (P=.001). Sixteen patients (8%) were clinically diagnosed with lymphogranuloma venereum (LGV); 1 plausible case of LGV was found by MIF. In Madagascar, primary care of genital ulcers should include syndromic treatment for syphilis and Chancroid.

  • comparison of enzyme immunoassays for antibodies to haemophilus ducreyi in a community outbreak of Chancroid in the united states
    The Journal of Infectious Diseases, 1997
    Co-Authors: Chengyen Chen, Stanley M Spinola, Kristen J Mertz, S A Morse
    Abstract:

    The performance of two EIAs (adsorption EIA and lipooligosaccharide [LOS] EIA) that detect antibodies to Haemophilus ducreyi was evaluated with serum specimens obtained from 163 patients (96 with genital ulcer disease [GUD]). Paired serum specimens (initial and follow-up) were obtained from 52 of the GUD patients. By use of initial serum specimens from 82 GUD patients whose etiologic agents for their ulcers had been identified, the adsorption EIA had a sensitivity and specificity for Chancroid of 53% and 71%, while the LOS EIA had a sensitivity and specificity of 48% and 89%, respectively. Sensitivity and specificity of the adsorption EIA increased to 78% and 84%, respectively, when the results of follow-up serum specimens were used to calculate optimal performance. The proportion of patients testing positive for H. ducreyi who had anti-H. ducreyi IgG antibodies, as determined by adsorption EIA, increased with the duration of infection, thus limiting the role of EIAs in the diagnosis of Chancroid.

  • Chancroid and Haemophilus ducreyi: an update.
    Clinical Microbiology Reviews, 1995
    Co-Authors: D L Trees, S A Morse
    Abstract:

    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.

  • multistrain outbreak of Chancroid in san francisco 1989 1991
    The Journal of Infectious Diseases, 1993
    Co-Authors: Jennifer Flood, Ruth M Greenblatt, Samuel K Sarafian, Gail Bolan, Claudia J Lammel, Joseph Engelman, Geo F Brooks, Arthur Back, S A Morse
    Abstract:

    Restriction fragment length polymorphism (RFLP) and plasmid analyses were used to evaluate an outbreak of Haemophilus ducreyi in San Francisco. Fifty-four cases of culture-confirmed Chancroid occurred between May 1989 and May 1991. Of these, 46 (96%) were in men and 35 (65%) were in blacks; the median age of patients was 34 years. Among the 32 isolates submitted for RFLP and plasmid analyses, six different HindIII RFLP patterns were identified. Two RFLP types were found in patients who had recently traveled to Los Angeles, Korea, or El Salvador. Four RFLP types appeared to be acquired locally and were more common among blacks (P = .002), in patients with a history of a sexually transmitted disease (P = .01), and in those who used drugs or exchanged drugs or money for sex (P = .08). The use of RFLP analysis confirmed that this outbreak was associated with multiple strains of H. ducreyi and allowed for the identification of risk factors for locally acquired Chancroid.