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SUMMARYChancroid, a sexually transmitted infection caused by Haemophilus ducreyi, is characterized by painful genital ulcers (GU) and inguinal lymphadenitis. H. ducreyi was recently described as a major cause of non-sexually transmitted cutaneous ulcers (CU) on the lower legs in children in yaws-endemic regions. This review explores the relationship between CU and GU strains of H. ducreyi; their clinical presentation, diagnosis, epidemiology, and treatment; and how findings from a human challenge model relate to GU and CU. We contrast the decline of GU with the persistence of CU caused by H. ducreyi. Factors such as transmission dynamics, control, and elimination efforts are discussed. Syndromic management and targeted treatment of sex workers can eradicate chancroid, while skin colonization by CU strains and environmental factors may necessitate topical treatments or vaccination for CU eradication. Efforts should focus on identifying additional reservoirs of CU strains, improving hygiene, and eliminating asymptomatic colonization to eradicate this painful infection in children.
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Rollet's Mixed Chancre is a clinical presentation of sexually transmitted infections (STI), involving the coexistence of Haemophilus ducreyi and Treponema pallidum at the same site of infection. Here, we report a case of Rollet's Mixed Chancre in a 32-year-old Brazilian woman. On physical examination she presented with a unilateral bubo measuring approximately 5 × 3 centimeters in diameter, in association with an ulcerated lesion that evolved for 10 days at the inguinal region. She was successfully treated at a health unit with antibiotics. Rollet's Mixed Chancre, though uncommon, poses diagnostic challenges. This case highlights the importance of considering rare STI manifestations. Moreover, comprehensive STI screening and adherence to treatment guidelines are essential for effective management and prevention of further transmission.
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Haemophilus ducreyi causes the genital ulcer disease chancroid and painful cutaneous ulcers in children who live in the tropics. To acquire heme from the host, H. ducreyi expresses a TonB-dependent hemoglobin receptor, HgbA, which is necessary and sufficient for H. ducreyi to progress to the pustular stage of disease in a controlled human infection model. HgbA transports hemoglobin across the outer membrane; how heme is transported across the cytoplasmic membrane is unclear. In previous studies, transcripts encoding the YfeABCD heme transporter were upregulated in experimental lesions caused by H. ducreyi in human volunteers, suggesting the latter may have a role in virulence. Here we constructed a double deletion mutant, 35000HPΔyfeABΔyfeCD, which exhibited growth defects relative to its parent 35000HP in media containing human hemoglobin as an iron source. Five human volunteers were inoculated at three sites on the skin overlying the deltoid with each strain. The results of the trial showed that papules formed at 100% (95% CI, 71.5, 100) at both 35000HP and 35000HPΔyfeABΔyfeCD-inoculated sites (P = 1.0). Pustules formed at 60% (95% CI, 25.9, 94.1) at parent-inoculated sites and 53% (95% CI, 18.3, 88.4) at mutant-inoculated sites (P = 0.79). Thus, the ABC transporter encoded by yfeAB and yfeCD was dispensable for H. ducreyi virulence in humans. In the absence of YfeABCD, H. ducreyi likely utilizes other periplasmic binding proteins and ABC-transporters such as HbpA, SapABCDF, and DppBCDF to shuttle heme from the periplasm into the cytoplasm, underscoring the importance of redundancy of such systems in gram-negative pathogens.
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Proteínas Bacterianas , Chancroide , Haemophilus ducreyi , Hierro , Haemophilus ducreyi/genética , Haemophilus ducreyi/patogenicidad , Haemophilus ducreyi/metabolismo , Humanos , Chancroide/microbiología , Chancroide/patología , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Virulencia , Hierro/metabolismo , Masculino , Adulto , Hemo/metabolismoRESUMEN
Cutaneous ulcers are common in yaws-endemic areas. Although often attributed to 'Treponema pallidum subsp. pertenue' and Haemophilus ducreyi, quantitative PCR has highlighted a significant proportion of these ulcers are negative for both pathogens and are considered idiopathic. This is a retrospective analysis utilising existing 16S rRNA sequencing data from two independent yaws studies that took place in Ghana and the Solomon Islands. We characterized bacterial diversity in 38 samples to identify potential causative agents for idiopathic cutaneous ulcers. We identified a diverse bacterial profile, including Arcanobacterium haemolyticum, Campylobacter concisus, Corynebacterium diphtheriae, Staphylococcus spp. and Streptococcus pyogenes, consistent with findings from previous cutaneous ulcer microbiome studies. No single bacterial species was universally present across all samples. The most prevalent bacterium, Campylobacter ureolyticus, appeared in 42% of samples, suggesting a multifactorial aetiology for cutaneous ulcers in yaws-endemic areas. This study emphasizes the need for a nuanced understanding of potential causative agents. The findings prompt further exploration into the intricate microbial interactions contributing to idiopathic yaw-like ulcers, guiding future research toward comprehensive diagnostic and therapeutic strategies.
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Microbiota , ARN Ribosómico 16S , Úlcera Cutánea , Humanos , ARN Ribosómico 16S/genética , Úlcera Cutánea/microbiología , Ghana , Masculino , Buba/microbiología , Buba/diagnóstico , Estudios Retrospectivos , Femenino , Adulto , Bacterias/genética , Bacterias/clasificación , Bacterias/aislamiento & purificación , Melanesia , Persona de Mediana Edad , Staphylococcus/genética , Staphylococcus/aislamiento & purificación , Staphylococcus/clasificación , Streptococcus pyogenes/genética , Streptococcus pyogenes/aislamiento & purificación , Streptococcus pyogenes/clasificación , Arcanobacterium/genética , Arcanobacterium/aislamiento & purificación , Campylobacter/genética , Campylobacter/aislamiento & purificación , Campylobacter/clasificaciónRESUMEN
Haemophilus ducreyi is a causative agent of cutaneous ulcers in children who live in the tropics and of the genital ulcer disease chancroid in sexually active persons. In the anaerobic environment of abscesses and ulcers, anaerobic respiration and mixed acid fermentation (MAF) can be used to provide cellular energy. In Escherichia coli, MAF produces formate, acetate, lactate, succinate, and ethanol; however, MAF has not been studied in H. ducreyi. In human challenge experiments with H. ducreyi 35000HP, transcripts of the formate transporter FocA and pyruvate formate lyase (PflB) were upregulated in pustules compared to the inocula. We made single and double mutants of focA and pflB in 35000HP. Growth of 35000HPΔfocA was similar to 35000HP, but 35000HPΔpflB and 35000HPΔfocA-pflB had growth defects during both aerobic and anaerobic growth. Mutants lacking pflB did not secrete formate into the media. However, formate was secreted into the media by 35000HPΔfocA, indicating that H. ducreyi has alternative formate transporters. The pH of the media during anaerobic growth decreased for 35000HP and 35000HPΔfocA, but not for 35000HPΔpflB or 35000HPΔfocA-pflB, indicating that pflB is the main contributor to media acidification during anaerobic growth. We tested whether formate production and transport were required for virulence in seven human volunteers in a mutant versus parent trial between 35000HPΔfocA-pflB and 35000HP. The pustule formation rate was similar for 35000HP (42.9%)- and 35000HPΔfocA-pflB (62%)-inoculated sites. Although formate production occurs during in vitro growth and focA-pflB transcripts are upregulated during human infection, focA and pflB are not required for virulence in humans.
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Proteínas de Escherichia coli , Haemophilus ducreyi , Niño , Humanos , Haemophilus ducreyi/genética , Virulencia , Úlcera , Voluntarios Sanos , Formiatos , Escherichia coli , Proteínas de Transporte de MembranaRESUMEN
Compared with wounded skin, ascorbic acid is enriched in pustules of humans experimentally infected with Haemophilus ducreyi. Compared with the broth-grown inocula, transcription of the H. ducreyi ulaABCD operon, which encodes genes for ascorbic acid uptake, is increased in pustules. We hypothesized that ascorbic acid uptake plays a role in H. ducreyi virulence. Five volunteers were infected with both H. ducreyi strain 35000HP and its isogenic ulaABCD deletion mutant at multiple sites; the papule and pustule formation rates of the mutant and parent strains were similar. Thus, ascorbic acid uptake is not essential for H. ducreyi virulence in humans.
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Chancroide , Haemophilus ducreyi , Humanos , Haemophilus ducreyi/genética , Virulencia , Chancroide/genética , Ácido Ascórbico , OperónRESUMEN
Few studies have investigated host-bacterial interactions at sites of infection in humans using transcriptomics and metabolomics. Haemophilus ducreyi causes cutaneous ulcers in children and the genital ulcer disease chancroid in adults. We developed a human challenge model in which healthy adult volunteers are infected with H. ducreyi on the upper arm until they develop pustules. Here, we characterized host-pathogen interactions in pustules using transcriptomics and metabolomics and examined interactions between the host transcriptome and metabolome using integrated omics. In a previous pilot study, we determined the human and H. ducreyi transcriptomes and the metabolome of pustule and wounded sites of 4 volunteers (B. Griesenauer, T. M. Tran, K. R. Fortney, D. M. Janowicz, et al., mBio 10:e01193-19, 2019, https://doi.org/10.1128/mBio.01193-19). While we could form provisional transcriptional networks between the host and H. ducreyi, the study was underpowered to integrate the metabolome with the host transcriptome. To better define and integrate the transcriptomes and metabolome, we used samples from both the pilot study (n = 4) and new volunteers (n = 8) to identify 5,495 human differentially expressed genes (DEGs), 123 H. ducreyi DEGs, 205 differentially abundant positive ions, and 198 differentially abundant negative ions. We identified 42 positively correlated and 29 negatively correlated human-H. ducreyi transcriptome clusters. In addition, we defined human transcriptome-metabolome networks consisting of 9 total clusters, which highlighted changes in fatty acid metabolism and mitigation of oxidative damage. Taken together, the data suggest a mixed pro- and anti-inflammatory environment and rewired central metabolism in the host that provides a hostile, nutrient-limited environment for H. ducreyi. IMPORTANCE Interactions between the host and bacteria at sites of infection in humans are poorly understood. We inoculated human volunteers on the upper arm with the skin pathogen H. ducreyi or a buffer control and biopsied the resulting infected and sham-inoculated sites. We performed dual transcriptome sequencing (RNA-seq) and metabolic analysis on the biopsy samples. Network analyses between the host and bacterial transcriptomes and the host transcriptome-metabolome network were used to identify molecules that may be important for the virulence of H. ducreyi in the human host. Our results suggest that the pustule is highly oxidative, contains both pro- and anti-inflammatory components, and causes metabolic shifts in the host, to which H. ducreyi adapts to survive. To our knowledge, this is the first study to integrate transcriptomic and metabolomic responses to a single bacterial pathogen in the human host.
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Chancroide , Haemophilus ducreyi , Adulto , Niño , Humanos , Haemophilus ducreyi/genética , Proyectos Piloto , Chancroide/genética , Piel/microbiología , Estrés OxidativoRESUMEN
Genital ulcer disease (GUD) continues to be an important cause of morbidity and mortality worldwide. It is an important risk factor for the acquisition of HIV. GUD is mainly caused by five sexually transmitted infections. Three pathogens most frequently associated with GUD are herpes simplex virus 2 (HSV-2), Treponema pallidum, and Haemophilus ducreyi. Although their prevalence varies among different geographical regions, HSV-2 is the leading cause of this syndrome globally. In recent years, there has been an epidemiological transition of HSV-1 with a growing role of this virus as a causative agent of GUD. GUD may present with unique features depending on the etiological agent that can help clinicians identify the etiology and start treatment. However, owing to atypical presentations and co-infections, an accurate clinical diagnosis is often a challenge without confirmatory laboratory tests. Standard methods used to detect the causative pathogens of GUD have limitations. Molecular methods can provide a more sensitive and rapid microbiological diagnosis, with detection of the pathogen from the clinical sample directly. In situations where no laboratory support is available, the syndromic approach for management should be followed. The current scenario, clinical presentation (typical and atypical), laboratory diagnosis, and management of GUD will be discussed in this review. We searched PubMed literature and Google search engine using the terms "genital ulcer disease," "epidemiology of genital ulcer disease," and "clinical features of genital ulcer disease and atypical presentations" and relevant literature was selected to provide current perspectives of GUD.
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Haemophilus ducreyi causes cutaneous ulcers in children and the genital ulcer disease chancroid in adults. In humans, H. ducreyi is found in the anaerobic environment of an abscess; previous studies comparing bacterial gene expression levels in pustules with the inocula (â¼4-h aerobic mid-log-phase cultures) identified several upregulated differentially expressed genes (DEGs) that are associated with anaerobic metabolism. To determine how H. ducreyi alters its gene expression in response to anaerobiosis, we performed RNA sequencing (RNA-seq) on both aerobic and anaerobic broth cultures harvested after 4, 8, and 18 h of growth. Principal-coordinate analysis (PCoA) plots showed that anaerobic growth resulted in distinct transcriptional profiles compared to aerobic growth. During anaerobic growth, early-time-point comparisons (4 versus 8 h) identified few DEGs at a 2-fold change in expression and a false discovery rate (FDR) of <0.01. By 18 h, we observed 18 upregulated and 16 downregulated DEGs. DEGs involved in purine metabolism, the uptake and use of alternative carbon sources, toxin production, nitrate reduction, glycine metabolism, and tetrahydrofolate synthesis were upregulated; DEGs involved in electron transport, thiamine biosynthesis, DNA recombination, peptidoglycan synthesis, and riboflavin synthesis or modification were downregulated. To examine whether transcriptional changes that occur during anaerobiosis overlap those that occur during infection of human volunteers, we compared the overlap of DEGs obtained from 4 h of aerobic growth to 18 h of anaerobic growth to those found between the inocula and pustules in previous studies; the DEGs significantly overlapped. Thus, a major component of H. ducreyi gene regulation in vivo involves adaptation to anaerobiosis. IMPORTANCE In humans, H. ducreyi resides in the anaerobic environment of an abscess and appears to upregulate genes involved in anaerobic metabolism. How anaerobiosis alone affects gene transcription in H. ducreyi is unknown. Using RNA-seq, we investigated how anaerobiosis affects gene transcription over time compared to aerobic growth. Our results suggest that a substantial component of H. ducreyi gene regulation in vivo overlaps the organism's response to anaerobiosis in vitro. Our data identify potential therapeutic targets that could be inhibited during in vivo growth.
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Haemophilus ducreyi , Absceso , Adulto , Anaerobiosis , Proteínas Bacterianas/metabolismo , Niño , Haemophilus ducreyi/genética , Haemophilus ducreyi/metabolismo , Voluntarios Sanos , HumanosRESUMEN
Exudative cutaneous ulcers (CU) in yaws-endemic areas are associated with Treponema pallidum subsp. pertenue (TP) and Haemophilus ducreyi (HD), but one-third of CU cases are idiopathic (IU). Using mass drug administration (MDA) of azithromycin, a yaws eradication campaign on Lihir Island in Papua New Guinea reduced but failed to eradicate yaws; IU rates remained constant throughout the campaign. To identify potential etiologies of IU, we obtained swabs of CU lesions (n = 279) and of the skin of asymptomatic controls (AC; n = 233) from the Lihir Island cohort and characterized their microbiomes using a metagenomics approach. CU bacterial communities were less diverse than those of the AC. Using real-time multiplex PCR with pathogen-specific primers, we separated CU specimens into HD-positive (HD+), TP+, HD+TP+, and IU groups. Each CU subgroup formed a distinct bacterial community, defined by the species detected and/or the relative abundances of species within each group. Streptococcus pyogenes was the most abundant organism in IU (22.65%) and was enriched in IU compared to other ulcer groups. Follow-up samples (n = 31) were obtained from nonhealed ulcers; the average relative abundance of S. pyogenes was 30.11% in not improved ulcers and 0.88% in improved ulcers, suggesting that S. pyogenes in the not improved ulcers may be azithromycin resistant. Catonella morbi was enriched in IU that lacked S. pyogenes As some S. pyogenes and TP strains are macrolide resistant, penicillin may be the drug of choice for CU azithromycin treatment failures. Our study will aid in the design of diagnostic tests and selective therapies for CU.IMPORTANCE Cutaneous ulcers (CU) affect approximately 100,000 children in the tropics each year. While two-thirds of CU are caused by Treponema pallidum subspecies pertenue and Haemophilus ducreyi, the cause(s) of the remaining one-third is unknown. Given the failure of mass drug administration of azithromycin to eradicate CU, the World Health Organization recently proposed an integrated disease management strategy to control CU. Success of this strategy requires determining the unknown cause(s) of CU. By using 16S rRNA gene sequencing of swabs obtained from CU and the skin of asymptomatic children, we identified another possible cause of skin ulcers, Streptococcus pyogenes Although S. pyogenes is known to cause impetigo and cellulitis, this is the first report implicating the organism as a causal agent of CU. Inclusion of S. pyogenes into the integrated disease management plan will improve diagnostic testing and treatment of this painful and debilitating disease of children and strengthen elimination efforts.
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Úlcera Cutánea/complicaciones , Úlcera Cutánea/microbiología , Streptococcus pyogenes/aislamiento & purificación , Buba/complicaciones , Buba/microbiología , Antibacterianos/uso terapéutico , Azitromicina/uso terapéutico , Niño , Clostridiales , Haemophilus ducreyi , Humanos , Metagenómica , Microbiota , Papúa Nueva Guinea/epidemiología , Reacción en Cadena de la Polimerasa , Estudios Prospectivos , ARN Ribosómico 16S , Úlcera Cutánea/tratamiento farmacológico , Úlcera Cutánea/epidemiología , Streptococcus pyogenes/genética , Treponema , Úlcera , Buba/tratamiento farmacológico , Buba/epidemiologíaRESUMEN
Cutaneous ulcers in the tropics are a painful and debilitating condition that anchors people into poverty. In rural regions of the South Pacific, infectious cutaneous ulcers are caused mainly by bacteria, including Treponema pallidum pertenue (yaws), Haemophilus ducreyi, and polymicrobial ulcers. For this group of infections the term cutaneous ulcer disease (CUD) is proposed. Some infections can cause malformations on the bone that have a permanent impact on lives in endemic communities. Better characterization of CUD may help design diagnostic tools and more effective antimicrobial therapies. This review updates the knowledge of CUD and discusses optimized terminology and syndromic management.
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Antibacterianos/uso terapéutico , Chancroide , Enfermedades Desatendidas , Enfermedades Cutáneas Bacterianas , Úlcera Cutánea , Buba , Bacillaceae , Bacteroides , Infecciones por Bacteroides/diagnóstico , Infecciones por Bacteroides/tratamiento farmacológico , Infecciones por Bacteroides/epidemiología , Chancroide/diagnóstico , Chancroide/tratamiento farmacológico , Chancroide/epidemiología , Coinfección/diagnóstico , Coinfección/tratamiento farmacológico , Coinfección/epidemiología , Coinfección/microbiología , Fusobacterium , Infecciones por Fusobacterium/diagnóstico , Infecciones por Fusobacterium/tratamiento farmacológico , Infecciones por Fusobacterium/epidemiología , Haemophilus ducreyi , Humanos , Islas del Pacífico/epidemiología , Saneamiento , Enfermedades Cutáneas Bacterianas/diagnóstico , Enfermedades Cutáneas Bacterianas/tratamiento farmacológico , Enfermedades Cutáneas Bacterianas/epidemiología , Enfermedades Cutáneas Bacterianas/microbiología , Úlcera Cutánea/diagnóstico , Úlcera Cutánea/tratamiento farmacológico , Úlcera Cutánea/epidemiología , Úlcera Cutánea/microbiología , Treponema , Treponema pallidum , Infecciones por Treponema/diagnóstico , Infecciones por Treponema/tratamiento farmacológico , Infecciones por Treponema/epidemiología , Buba/diagnóstico , Buba/tratamiento farmacológico , Buba/epidemiologíaRESUMEN
Yaws is a skin debilitating disease caused by Treponema pallidum subspecies pertenue with most cases reported in children. World Health Organization (WHO) aims at total eradication of this disease through mass treatment of suspected cases followed by an intensive follow-up program. However, effective diagnosis is pivotal in the successful implementation of this control program. Recombinase polymerase amplification (RPA), an isothermal nucleic acid amplification technique offers a wider range of differentiation of pathogens including those isolated from chronic skin ulcers with similar characteristics such as Haemophilus ducreyi (H. ducreyi). We have developed a RPA assay for the simultaneous detection of Treponema pallidum (T. pallidum) and H. ducreyi (TPHD-RPA). The assay demonstrated no cross-reaction with other pathogens and enable detection of T. pallidum and H. ducreyi within 15 min at 42 °C. The RPA assay was validated with 49 clinical samples from individuals confirmed to have yaws by serological tests. Comparing the developed assay with commercial multiplex real-time PCR, the assay demonstrated 94% and 95% sensitivity for T. pallidum and H. ducreyi, respectively and 100% specificity. This simple novel TPHD-RPA assay enables the rapid detection of both T. pallidum and H. ducreyi in yaws-like lesions. This test could support the yaws eradication efforts by ensuring reliable diagnosis, to enable monitoring of program success and planning of follow-up interventions at the community level.
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Yaws, a neglected tropical disease caused by the bacterium Treponema pallidum subspecies pertenue, manifests as ulcerative skin lesions. Nucleic acid amplification tests, like loop-mediated isothermal amplification (LAMP), are versatile tools to distinguish yaws from infections that cause similar skin lesions, primarily Haemophilus ducreyi. We developed a novel molecular test to simultaneously detect T. pallidum and H. ducreyi based on mediator displacement LAMP. We validated the T. pallidum and H. ducreyi LAMP (TPHD-LAMP) by testing 293 clinical samples from patients with yaws-like lesions. Compared with quantitative PCR, the TPHD-LAMP demonstrated high sensitivity and specificity for T. pallidum (84.7% sensitivity, 95.7% specificity) and H. ducreyi (91.6% sensitivity, 84.8% specificity). This novel assay provided rapid molecular confirmation of T. pallidum and H. ducreyi DNA and might be suitable for use at the point of care. TPHD-LAMP could support yaws eradication by improving access to molecular diagnostic tests at the district hospital level.
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Chancroide/diagnóstico , Haemophilus ducreyi/aislamiento & purificación , Treponema pallidum/aislamiento & purificación , Buba/diagnóstico , Chancroide/microbiología , Niño , Femenino , Ghana , Humanos , Masculino , Técnicas de Diagnóstico Molecular , Técnicas de Amplificación de Ácido Nucleico , Papúa Nueva Guinea , Sensibilidad y Especificidad , Buba/microbiologíaRESUMEN
The obligate human pathogen Haemophilus ducreyi causes both cutaneous ulcers in children and sexually transmitted genital ulcers (chancroid) in adults. Pathogenesis is dependent on avoiding phagocytosis and exploiting the suppurative granuloma-like niche, which contains a myriad of innate immune cells and memory T cells. Despite this immune infiltrate, long-lived immune protection does not develop against repeated H. ducreyi infections-even with the same strain. Most of what we know about infectious skin diseases comes from naturally occurring infections and/or animal models; however, for H. ducreyi, this information comes from an experimental model of infection in human volunteers that was developed nearly three decades ago. The model mirrors the progression of natural disease and serves as a valuable tool to determine the composition of the immune cell infiltrate early in disease and to identify host and bacterial factors that are required for the establishment of infection and disease progression. Most recently, holistic investigation of the experimentally infected skin microenvironment using multiple "omics" techniques has revealed that non-canonical bacterial virulence factors, such as genes involved in central metabolism, may be relevant to disease progression. Thus, the immune system not only defends the host against H. ducreyi, but also dictates the nutrient availability for the invading bacteria, which must adapt their gene expression to exploit the inflammatory metabolic niche. These findings have broadened our view of the host-pathogen interaction network from considering only classical, effector-based virulence paradigms to include adaptations to the metabolic environment. How both host and bacterial factors interact to determine infection outcome is a current focus in the field. Here, we review what we have learned from experimental H. ducreyi infection about host-pathogen interactions, make comparisons to what is known for other skin pathogens, and discuss how novel technologies will deepen our understanding of this infection.
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Chancroide/microbiología , Haemophilus ducreyi/patogenicidad , Interacciones Huésped-Patógeno/inmunología , Úlcera Cutánea/microbiología , Presentación de Antígeno , Proteínas Bacterianas/fisiología , Catelicidinas/fisiología , Chancroide/inmunología , Chancroide/patología , Citocinas/metabolismo , Defensinas/fisiología , Células Dendríticas/inmunología , Método Doble Ciego , Regulación Bacteriana de la Expresión Génica , Haemophilus ducreyi/genética , Haemophilus ducreyi/inmunología , Humanos , Subgrupos Linfocitarios/inmunología , Macrófagos/inmunología , Metaboloma , Mutación , Neutrófilos/inmunología , Experimentación Humana no Terapéutica , Fagocitosis , Úlcera Cutánea/inmunología , Úlcera Cutánea/patología , Transcriptoma , Factores de Virulencia/inmunologíaAsunto(s)
Colchicina/administración & dosificación , Úlcera/tratamiento farmacológico , Vitamina B 12/administración & dosificación , Colchicina/uso terapéutico , Errores Diagnósticos , Ácido Fólico/sangre , Enfermedades de los Genitales Masculinos/diagnóstico , Enfermedades de los Genitales Masculinos/tratamiento farmacológico , Herpes Genital/diagnóstico , Humanos , Masculino , Resultado del Tratamiento , Úlcera/diagnóstico , Vitamina B 12/uso terapéutico , Deficiencia de Vitamina B 12/sangre , Deficiencia de Vitamina B 12/tratamiento farmacológico , Adulto JovenRESUMEN
BACKGROUND: Yaws is a neglected tropical disease and results in lesions of skin, soft tissues and bones. PCR plays an important part in surveillance. METHODS: Children suspected to have yaws were enrolled. From the largest lesion, paired swabs were collected, one in transport medium and one as a dry swab. In children with multiple lesions we collected additional swabs from up to four subsequent lesions. Swabs in transport medium were maintained in a cold chain while dry swabs were stored at ambient temperature. Swabs were tested by PCR for Treponema pallidum and Haemophilus ducreyi. RESULTS: Of 55 individuals, 10 (18%) had at least one positive PCR for T. pallidum and 12 (22%) had at least one positive result for H. ducreyi. Concordance was 100% between swabs in transport medium and dry swabs. One patient had PCR-confirmed yaws on the swab of a third lesion when both the first and second lesions were PCR-negative. CONCLUSIONS: Storing swabs in transport medium and transporting in a cold chain did not improve yield, however, detection of T. pallidum is increased by swabbing additional lesions. As the target for yaws is eradication, approaches to sample collection need revisiting to ensure cases are not missed.
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Reacción en Cadena de la Polimerasa/métodos , Buba/diagnóstico , Niño , Femenino , Ghana , Haemophilus ducreyi , Humanos , Masculino , Piel/microbiología , Treponema pallidumRESUMEN
A major gap in understanding infectious diseases is the lack of information about molecular interaction networks between pathogens and the human host. Haemophilus ducreyi causes the genital ulcer disease chancroid in adults and is a leading cause of cutaneous ulcers in children in the tropics. We developed a model in which human volunteers are infected on the upper arm with H. ducreyi until they develop pustules. To define the H. ducreyi and human interactome, we determined bacterial and host transcriptomic and host metabolomic changes in pustules. We found that in vivoH. ducreyi transcripts were distinct from those in the inocula, as were host transcripts in pustule and wounded control sites. Many of the upregulated H. ducreyi genes were found to be involved in ascorbic acid and anaerobic metabolism and inorganic ion/nutrient transport. The top 20 significantly expressed human pathways showed that all were involved in immune responses. We generated a bipartite network for interactions between host and bacterial gene transcription; multiple positively correlated networks contained H. ducreyi genes involved in anaerobic metabolism and host genes involved with the immune response. Metabolomic studies showed that pustule and wounded samples had different metabolite compositions; the top ion pathway involved ascorbate and aldarate metabolism, which correlated with the H. ducreyi transcriptional response and upregulation of host genes involved in ascorbic acid recycling. These data show that an interactome exists between H. ducreyi and the human host and suggest that H. ducreyi exploits the metabolic niche created by the host immune response.IMPORTANCE Dual RNA sequencing (RNA-seq) offers the promise of determining an interactome at a transcriptional level between a bacterium and the host but has yet to be done on any bacterial infection in human tissue. We performed dual RNA-seq and metabolomics analyses on wounded and infected sites following experimental infection of the arm with H. ducreyi Our results suggest that H. ducreyi survives in an abscess by utilizing l-ascorbate as an alternative carbon source, possibly taking advantage of host ascorbic acid recycling, and that H. ducreyi also adapts by upregulating genes involved in anaerobic metabolism and inorganic ion and nutrient transport. To our knowledge, this is the first description of an interaction network between a bacterium and the human host at a site of infection.
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Chancroide/genética , Redes Reguladoras de Genes , Haemophilus ducreyi/genética , Haemophilus ducreyi/patogenicidad , Interacciones Huésped-Patógeno/genética , Metaboloma , Adulto , Anaerobiosis , Ácido Ascórbico/metabolismo , Proteínas Bacterianas/genética , Chancroide/inmunología , Femenino , Perfilación de la Expresión Génica , Humanos , Masculino , Metabolómica , Persona de Mediana Edad , RNA-SeqRESUMEN
Haemophilus ducreyi causes chancroid and is a major cause of cutaneous ulcers in children. Due to environmental reservoirs, both class I and class II H. ducreyi strains persist in cutaneous ulcer regions of endemicity following mass drug administration of azithromycin, suggesting the need for a vaccine. The hemoglobin receptor (HgbA) is a leading vaccine candidate, but its efficacy in animal models is class specific. Controlled human infection models can be used to evaluate vaccines, but only a class I strain (35000HP) has been characterized in this model. As a prelude to evaluating HgbA vaccines in the human model, we tested here whether a derivative of 35000HP containing a class II hgbA allele (FX548) is as virulent as 35000HP in humans. In eight volunteers infected at three sites with each strain, the papule formation rate was 95.8% for 35000HP versus 62.5% for FX548 (P = 0.021). Excluding doses of FX548 that were ≥2-fold higher than those of 35000HP, the pustule formation rate was 25% for 35000HP versus 11.7% for FX548 (P = 0.0053). By Western blot analysis, FX548 and 35000HP expressed equivalent amounts of HgbA in whole-cell lysates and outer membranes. The growth of FX548 and 35000HP was similar in media containing hemoglobin or hemin. By whole-genome sequencing and single-nucleotide polymorphism analysis, FX548 contained no mutations in open reading frames other than hgbA We conclude that by an unknown mechanism, FX548 is partially attenuated in humans and is not a suitable strain for HgbA vaccine efficacy trials in the model.
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Proteínas Bacterianas/genética , Proteínas Bacterianas/inmunología , Proteínas Portadoras/genética , Proteínas Portadoras/inmunología , Chancroide/prevención & control , Vacunas contra Haemophilus/inmunología , Haemophilus ducreyi/inmunología , Adulto , Alelos , Proteínas Bacterianas/administración & dosificación , Proteínas Portadoras/administración & dosificación , Chancroide/inmunología , Chancroide/microbiología , Femenino , Vacunas contra Haemophilus/administración & dosificación , Vacunas contra Haemophilus/genética , Haemophilus ducreyi/genética , Humanos , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
The primary role of bacterial periplasmic binding proteins is sequestration of essential metabolites present at a low concentration in the periplasm and making them available for active transporters that transfer these ligands into the bacterial cell. The periplasmic binding proteins (SiaPs) from the tripartite ATP-independent periplasmic (TRAP) transport system that transports mammalian host-derived sialic acids have been well studied from different pathogenic bacteria, including Haemophilus influenzae, Fusobacterium nucleatum, Pasteurella multocida, and Vibrio cholerae SiaPs bind the sialic acid N-acetylneuraminic acid (Neu5Ac) with nanomolar affinity by forming electrostatic and hydrogen-bonding interactions. Here, we report the crystal structure of a periplasmic binding protein (SatA) of the ATP-binding cassette (ABC) transport system from the pathogenic bacterium Haemophilus ducreyi The structure of Hd-SatA in the native form and sialic acid-bound forms (with Neu5Ac and N-glycolylneuraminic acid (Neu5Gc)), determined to 2.2, 1.5, and 2.5 Å resolutions, respectively, revealed a ligand-binding site that is very different from those of the SiaPs of the TRAP transport system. A structural comparison along with thermodynamic studies suggested that similar affinities are achieved in the two classes of proteins through distinct mechanisms, one enthalpically driven and the other entropically driven. In summary, our structural and thermodynamic characterization of Hd-SatA reveals that it binds sialic acids with nanomolar affinity and that this binding is an entropically driven process. This information is important for future structure-based drug design against this pathogen and related bacteria.
Asunto(s)
Haemophilus ducreyi/química , Ácido N-Acetilneuramínico/química , Proteínas Periplasmáticas/química , Cristalografía por Rayos X , Haemophilus ducreyi/genética , Haemophilus ducreyi/metabolismo , Ácido N-Acetilneuramínico/genética , Ácido N-Acetilneuramínico/metabolismo , Proteínas Periplasmáticas/genética , Proteínas Periplasmáticas/metabolismoRESUMEN
We describe the first case of chancroid seen in the Czech Republic, diagnosed in a 40-year-old heterosexual HIV-positive man. Despite genital localization of the ulcer, the transmission of Haemophilus ducreyi infection in our patient remains unclear, as he denied having sexual intercourse and he did not travel outside the Czech Republic for several months before the ulcer appeared. The correct diagnosis has been revealed by a multiplex nucleic acid amplification test. Physicians in countries in the eastern and central Europe region should be aware that chancroid can occur in their patients.