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1.
ACS Infect Dis ; 10(2): 251-269, 2024 02 09.
Artículo en Inglés | MEDLINE | ID: mdl-38295025

RESUMEN

In the recent decade, scientific communities have toiled to tackle the emerging burden of drug-resistant tuberculosis (DR-TB) and rapidly growing opportunistic nontuberculous mycobacteria (NTM). Among these, two neglected mycobacteria species of the Acinetobacter family, Mycobacterium leprae and Mycobacterium ulcerans, are the etiological agents of leprosy and Buruli ulcer infections, respectively, and fall under the broad umbrella of neglected tropical diseases (NTDs). Unfortunately, lackluster drug discovery efforts have been made against these pathogenic bacteria in the recent decade, resulting in the discovery of only a few countable hits and majorly repurposing anti-TB drug candidates such as telacebec (Q203), P218, and TB47 for current therapeutic interventions. Major ignorance in drug candidate identification might aggravate the dramatic consequences of rapidly spreading mycobacterial NTDs in the coming days. Therefore, this Review focuses on an up-to-date account of drug discovery efforts targeting selected druggable targets from both bacilli, including the accompanying challenges that have been identified and are responsible for the slow drug discovery. Furthermore, a succinct discussion of the all-new possibilities that could be alternative solutions to mitigate the neglected mycobacterial NTD burden and subsequently accelerate the drug discovery effort is also included. We anticipate that the state-of-the-art strategies discussed here may attract major attention from the scientific community to navigate and expand the roadmap for the discovery of next-generation therapeutics against these NTDs.


Asunto(s)
Úlcera de Buruli , Mycobacterium ulcerans , Mycobacterium , Humanos , Mycobacterium leprae , Úlcera de Buruli/tratamiento farmacológico , Úlcera de Buruli/microbiología , Úlcera de Buruli/patología
2.
J Infect Dis ; 228(11): 1630-1639, 2023 11 28.
Artículo en Inglés | MEDLINE | ID: mdl-37221015

RESUMEN

Mycobacterium ulcerans causes Buruli ulcer, the third most frequent mycobacterial disease after tuberculosis and leprosy. Transient clinical deteriorations, known as paradoxical reactions (PRs), occur in some patients during or after antibiotic treatment. We investigated the clinical and biological features of PRs in a prospective cohort of 41 patients with Buruli ulcer from Benin. Neutrophil counts decreased from baseline to day 90, and interleukin 6 (IL-6), granulocyte colony-stimulating factor, and vascular endothelial growth factor were the cytokines displaying a significant monthly decrease relative to baseline. PRs occurred in 10 (24%) patients. The baseline biological and clinical characteristics of the patients presenting with PRs did not differ significantly from those of the other patients. However, the patients with PRs had significantly higher IL-6 and tumor necrosis factor alpha (TNF-α) concentrations on days 30, 60, and 90 after the start of antibiotic treatment. The absence of a decrease in IL-6 and TNF-α levels during treatment should alert clinicians to the possibility of PR onset.


Asunto(s)
Úlcera de Buruli , Humanos , Úlcera de Buruli/tratamiento farmacológico , Estudios Prospectivos , Factor de Necrosis Tumoral alfa , Interleucina-6 , Factor A de Crecimiento Endotelial Vascular , Antibacterianos/uso terapéutico
3.
J Plast Surg Hand Surg ; 55(6): 339-344, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33645421

RESUMEN

INTRODUCTION: Infection by Mycobacterium ulcerans constitutes a neglected tropical disease whose prevalence seems to have overrun those of cutaneous tuberculosis and leprosy. Its aggressivity depends on a mycolactone toxin. Lesions may involve skin, tendon and bone with a large spectrum of manifestations: non-ulcerative (papules, nodules, plaques), ulcerative and oedematous presentations as well as osteomyelitis with muscular contraction and ankylosis. Upper limbs account for more than two thirds of the infection sites. Surgical treatment may involve tendon transpositions, partial and total skin grafts. Amputation is relegated to extreme cases. MATERIAL AND METHODS: Selected iconography from patients during the last 15 years is presented. At least 1500 cases had partial skin grafts (anterior thigh). Total skin grafts (inguinal region) were used in about 200 cases. Complex lesions involved 9 ilioinguinal flaps (5 boys, 4 girls, mean age 11.2 years, range 2-16 years), 5 tendon transfers (4 boys, one girl, mean age 15.4 years, range 12-19 years) and 3 resections of the first carpal row (2 girls, 1 boy, mean age 8 years, range 4-15 years). RESULTS AND DISCUSSION: Out of 9 ilioinguinal flaps mild, marginal necrosis was the only complication in 2 patients without flap loss. Mean hospital stay was 26.44 days (range, 18-41 days), with return to full weight-bearing after a mean of 12 weeks (range 9-25 weeks) after discharge. Functional thumb opposition to allow pencil prehension was achieved in all three cases of resection of first carpal row resection without postoperative complications.


Asunto(s)
Úlcera de Buruli , Procedimientos de Cirugía Plástica , Adolescente , Adulto , Úlcera de Buruli/cirugía , Niño , Preescolar , Humanos , Extremidad Superior/cirugía , Adulto Joven
5.
Expert Rev Clin Pharmacol ; 13(4): 391-401, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32310683

RESUMEN

INTRODUCTION: Pharmacological treatment of Buruli ulcer (Mycobacterium ulcerans infection; BU) is highly effective, as shown in two randomized trials in Africa. AREAS COVERED: We review BU drug treatment - in vitro, in vivo and clinical trials (PubMed: '(Buruli OR (Mycobacterium AND ulcerans)) AND (treatment OR therapy).' We also highlight the pathogenesis of M. ulcerans infection that is dominated by mycolactone, a secreted exotoxin, that causes skin and soft tissue necrosis, and impaired immune response and tissue repair. Healing is slow, due to the delayed wash-out of mycolactone. An array of repurposed tuberculosis and leprosy drugs appears effective in vitro and in animal models. In clinical trials and observational studies, only rifamycins (notably, rifampicin), macrolides (notably, clarithromycin), aminoglycosides (notably, streptomycin) and fluoroquinolones (notably, moxifloxacin, and ciprofloxacin) have been tested. EXPERT OPINION: A combination of rifampicin and clarithromycin is highly effective but lesions still take a long time to heal. Novel drugs like telacebec have the potential to reduce treatment duration but this drug may remain unaffordable in low-resourced settings. Research should address ulcer treatment in general; essays to measure mycolactone over time hold promise to use as a readout for studies to compare drug treatment schedules for larger lesions of Buruli ulcer.


Asunto(s)
Antibacterianos/farmacología , Úlcera de Buruli/tratamiento farmacológico , Mycobacterium ulcerans/efectos de los fármacos , Animales , Antibacterianos/administración & dosificación , Úlcera de Buruli/microbiología , Reposicionamiento de Medicamentos , Quimioterapia Combinada , Humanos , Macrólidos/metabolismo , Mycobacterium ulcerans/aislamiento & purificación , Ensayos Clínicos Controlados Aleatorios como Asunto , Cicatrización de Heridas/efectos de los fármacos
6.
Front Pharmacol ; 10: 378, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31031626

RESUMEN

Mycobacterium ulcerans is the bacillus responsible for Buruli ulcer, an infectious disease and the third most important mycobacterial disease worldwide, after tuberculosis and leprosy. M. ulcerans infection is a type of panniculitis beginning mostly with a nodule or an oedema, which can progress to large ulcerative lesions. The lesions are caused by mycolactone, the polyketide toxin of M. ulcerans. Mycolactone plays a central role for host colonization as it has immunomodulatory and analgesic effects. On one hand, mycolactone induces analgesia by targeting type-2 angiotensin II receptors (AT2R), causing cellular hyperpolarization and neuron desensitization. Indeed, a single subcutaneous injection of mycolactone into the mouse footpad induces a long-lasting hypoesthesia up to 48 h. It was suggested that the long-lasting hypoesthesia may result from the persistence of a significant amount of mycolactone locally following its injection, which could be probably due to its slow elimination from tissues. To verify this hypothesis, we investigated the correlation between hypoesthesia and mycolactone bioavailability directly at the tissue level. Various quantities of mycolactone were then injected in mouse tissue and hypoesthesia was recorded with nociception assays over a period of 48 h. The hypoesthesia was maximal 6 h after the injection of 4 µg mycolactone. The basal state was reached 48 h after injection, which demonstrated the absence of nerve damage. Surprisingly, mycolactone levels decreased strongly during the first hours with a reduction of 70 and 90% after 4 and 10 h, respectively. Also, mycolactone did not diffuse in neighboring skin tissue and only poorly into the bloodstream upon direct injection. Nevertheless, the remaining amount was sufficient to induce hypoesthesia during 24 h. Our results thus demonstrate that intact mycolactone is rapidly eliminated and that very small amounts of mycolactone are sufficient to induce hypoesthesia. Taken together, our study points out that mycolactone ought to be considered as a promising analgesic.

7.
J Leukoc Biol ; 105(2): 233-242, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30168876

RESUMEN

Buruli ulcer (BU), caused by Mycobacterium ulcerans (MU), is the third most important mycobacterial diseases after tuberculosis and leprosy in immunocompetent individuals. Although the mode of transmission remains an enigma, disease incidence has been strongly linked to disturbed environment and wetlands. The blunt of the diseases is recorded in West African countries along the Gulf of Guinea, and children 15 years and below account for about 48% of all cases globally. Prior to 2004, wide surgical excisions and debridement of infected necrotic tissues followed by skin grafting was the accepted definitive treatment of BU. However, introduction of antibiotic therapy, daily oral rifampicin (10 mg/kg) plus intramuscular injection of streptomycin (15 mg/kg), for 8 weeks by the WHO in 2004 has reduced surgery as an adjunct for correction of deformities and improved wound healing. An all-oral regimen is currently on clinical trial to replace the injectable. It is thought that a protective cloud of the cytotoxic toxin mycolactone kills infiltrating leucocytes leading to local immunosuppression and down-regulation of the systemic immune system. Our studies of lesions from BU patients treated with SR have demonstrated treatment-associated initiation of vigorous immune responses and the development of ectopic lymphoid tissue in the BU lesions. Despite these interventions, there are still challenges that bedevil the management of BU including paradoxical reactions, evolution of lesions after therapy, prolong viability of MU in BU lesions, and development of secondary bacterial infection. In this paper, we will mainly focus on the critical and pertinent challenges that undermine BU treatment toward effective control of BU.


Asunto(s)
Úlcera de Buruli/terapia , Animales , Úlcera de Buruli/complicaciones , Úlcera de Buruli/inmunología , Úlcera de Buruli/patología , Coinfección/microbiología , Coinfección/virología , Infecciones por VIH/complicaciones , Humanos , Terapia de Inmunosupresión , Mycobacterium ulcerans/fisiología
8.
Clin Microbiol Rev ; 32(1)2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-30429139

RESUMEN

Humans encounter mycobacterial species due to their ubiquity in different environmental niches. In many individuals, pathogenic mycobacterial species may breach our first-line barrier defenses of the innate immune system and modulate the activation of phagocytes to cause disease of the respiratory tract or the skin and soft tissues, sometimes resulting in disseminated infection. Cutaneous mycobacterial infections may cause a wide range of clinical manifestations, which are divided into four main disease categories: (i) cutaneous manifestations of Mycobacterium tuberculosis infection, (ii) Buruli ulcer caused by Mycobacterium ulcerans and other related slowly growing mycobacteria, (iii) leprosy caused by Mycobacterium leprae and Mycobacterium lepromatosis, and (iv) cutaneous infections caused by rapidly growing mycobacteria. Clinically, cutaneous mycobacterial infections present with widely different clinical presentations, including cellulitis, nonhealing ulcers, subacute or chronic nodular lesions, abscesses, superficial lymphadenitis, verrucous lesions, and other types of findings. Mycobacterial infections of the skin and subcutaneous tissue are associated with important stigma, deformity, and disability. Geography-based environmental exposures influence the epidemiology of cutaneous mycobacterial infections. Cutaneous tuberculosis exhibits different clinical phenotypes acquired through different routes, including via extrinsic inoculation of the tuberculous bacilli and dissemination to the skin from other sites, or represents hypersensitivity reactions to M. tuberculosis infection. In many settings, leprosy remains an important cause of neurological impairment, deformity, limb loss, and stigma. Mycobacterium lepromatosis, a mycobacterial species related to M. leprae, is linked to diffuse lepromatous leprosy of Lucio and Latapí. Mycobacterium ulcerans produces a mycolactone toxin that leads to subcutaneous tissue destruction and immunosuppression, resulting in deep ulcerations that often produce substantial disfigurement and disability. Mycobacterium marinum, a close relative of M. ulcerans, is an important cause of cutaneous sporotrichoid nodular lymphangitic lesions. Among patients with advanced immunosuppression, Mycobacterium kansasii, the Mycobacterium avium-intracellulare complex, and Mycobacterium haemophilum may cause cutaneous or disseminated disease. Rapidly growing mycobacteria, including the Mycobacterium abscessus group, Mycobacterium chelonei, and Mycobacterium fortuitum, are increasingly recognized pathogens in cutaneous infections associated particularly with plastic surgery and cosmetic procedures. Skin biopsies of cutaneous lesions to identify acid-fast staining bacilli and cultures represent the cornerstone of diagnosis. Additionally, histopathological evaluation of skin biopsy specimens may be useful in identifying leprosy, Buruli ulcer, and cutaneous tuberculosis. Molecular assays are useful in some cases. The treatment for cutaneous mycobacterial infections depends on the specific pathogen and therefore requires a careful consideration of antimicrobial choices based on official treatment guidelines.


Asunto(s)
Dermatitis/diagnóstico , Dermatitis/microbiología , Infecciones por Mycobacterium/diagnóstico , Infecciones por Mycobacterium/microbiología , Mycobacterium , Animales , Humanos , Mycobacterium/clasificación , Mycobacterium/fisiología
9.
Trop Med Infect Dis ; 3(2)2018 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-30274452

RESUMEN

Mycobacterium ulcerans is the causative agent of Buruli ulcer, also known in Australia as Daintree ulcer or Bairnsdale ulcer. This destructive skin disease is characterized by extensive and painless necrosis of the skin and soft tissue with the formation of large ulcers, commonly on the leg or arm. To date, 33 countries with tropical, subtropical and temperate climates in Africa, the Americas, Asia and the Western Pacific have reported cases of Buruli ulcer. The disease is rarely fatal, although it may lead to permanent disability and/or disfigurement if not treated appropriately or in time. It is the third most common mycobacterial infection in the world after tuberculosis and leprosy. The precise mode of transmission of M. ulcerans is yet to be elucidated. Nevertheless, it is possible that the mode of transmission varies with different geographical areas and epidemiological settings. The knowledge about the possible routes of transmission and potential animal reservoirs of M. ulcerans is poorly understood and still remains patchy. Infectious diseases arise from the interaction of agent, host and environment. The majority of emerging or remerging infectious disease in human populations is spread by animals: either wildlife, livestock or pets. Animals may act as hosts or reservoirs and subsequently spread the organism to the environment or directly to the human population. The reservoirs may or may not be the direct source of infection for the hosts; however, they play a major role in maintenance of the organism in the environment, and in the mode of transmission. This remains valid for M. ulcerans. Possums have been suggested as one of the reservoir of M. ulcerans in south-eastern Australia, where possums ingest M. ulcerans from the environment, amplify them and shed the organism through their faeces. We conducted a systematic review with selected key words on PubMed and INFORMIT databases to aggregate available published data on animal reservoirs of M. ulcerans around the world. After certain inclusion and exclusion criteria were implemented, a total of 17 studies was included in the review. A variety of animals around the world e.g., rodents, shrews, possums (ringtail and brushtail), horses, dogs, alpacas, koalas and Indian flap-shelled turtles have been recorded as being infected with M. ulcerans. The majority of studies included in this review identified animal reservoirs as predisposing to the emergence and reemergence of M. ulcerans infection. Taken together, from the selected studies in this systematic review, it is clear that exotic wildlife and native mammals play a significant role as reservoirs for M. ulcerans.

10.
Molecules ; 21(4): 445, 2016 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-27089314

RESUMEN

Buruli ulcer (BU) is the third most prevalent mycobacteriosis, after tuberculosis and leprosy. The currently recommended combination of rifampicin-streptomycin suffers from side effects and poor compliance, which leads to reliance on local herbal remedies. The objective of this study was to investigate the antimycobacterial properties and toxicity of selected medicinal plants. Sixty-five extracts from 27 plant species were screened against Mycobacterium ulcerans and Mycobacterium smegmatis, using the Resazurin Microtiter Assay (REMA). The cytotoxicity of promising extracts was assayed on normal Chang liver cells by an MTT assay. Twenty five extracts showed activity with minimal inhibitory concentration (MIC) values ranging from 16 µg/mL to 250 µg/mL against M. smegmatis, while 17 showed activity against M. ulcerans with MIC values ranging from 125 µg/mL to 250 µg/mL. In most of the cases, plant extracts with antimycobacterial activity showed no cytotoxicity on normal human liver cells. Exception were Carica papaya, Cleistopholis patens, and Polyalthia suaveolens with 50% cell cytotoxic concentrations (CC50) ranging from 3.8 to 223 µg/mL. These preliminary results support the use of some West African plants in the treatment of Buruli ulcer. Meanwhile, further studies are required to isolate and characterize the active ingredients in the extracts.


Asunto(s)
Antibacterianos/administración & dosificación , Úlcera de Buruli/tratamiento farmacológico , Mycobacterium ulcerans/efectos de los fármacos , Extractos Vegetales/administración & dosificación , África Occidental , Antibacterianos/química , Úlcera de Buruli/microbiología , Línea Celular , Proliferación Celular/efectos de los fármacos , Humanos , Hígado/citología , Hígado/efectos de los fármacos , Mycobacterium ulcerans/patogenicidad , Extractos Vegetales/química , Plantas Medicinales/química
11.
Int J Mycobacteriol ; 5 Suppl 1: S105, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28043490

RESUMEN

OBJECTIVE/BACKGROUND: Buruli ulcer, known as necrotizing skin disease caused by Mycobacterium ulcerans, has emerged as the most prevalent mycobacteriosis after leprosy and tuberculosis. Accordingly, it has been classified by the World Health Organization as a neglected disease with high significance in tropical areas, including Cameroon. So far, the control of the disease relies mainly on the rifampin-streptomycin combination. Despite its efficiency, it has shown considerable issues, including availability and side effects. Therefore, more effective and safer drugs are urgently warranted. For this fact, natural plant-based products have always been of great importance in drug discovery. Therefore, the present study was initiated to assess the antimycobacterial properties of four medicinal plants against M. ulcerans. METHODS: The methanolic and aqueous crude extracts prepared from Ficus binjamina, Ficus elastica, Ficus saussureana, and Terminalia superba were screened against M. ulcerans using the resazurin microtiter assay method. The phytochemical screening of promising extracts was performed to reveal bioactive components that might explain the exhibited activity. RESULTS: Out of the 24 tested extracts, 11 extracts showed promising activity with minimal inhibitory concentration ranging from 62.5µg/mL to 250µg/mL. The phytochemical screening revealed the presence of phenols, flavonoids, tanins, triterpenes, glucosides, and saponins. CONCLUSION: The obtained results further strengthened the exploitation of these extracts as potent hits in the treatment of Buruli ulcer. Meanwhile, further studies are required to fully characterize the bioactive compounds.

12.
J Ethnopharmacol ; 172: 297-311, 2015 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-26099634

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Buruli ulcer (BU) is the third most common mycobacterial infection in the world, after tuberculosis and leprosy and has recently been recognized as an important emerging disease. This disease is common in West Africa where more than 99% of the burden is felt and where most affected people live in remote areas with traditional medicine as primary or only option. Reports indicate that the ethnopharmacological control approach of the disease in such settings has shown promise. However, no or very few compilations of traditional knowledge in using medicinal plants to treat BU have been attempted so far. This review aimed to record medicinal plants used traditionally against BU in three countries in West Africa: Ivory Coast, Ghana and Benin and for which ethnopharmacological knowledge supported by pharmacological investigations has been reported. The information recorded in this review will support further pharmacological research to develop appropriate drugs for a better BU control. MATERIAL AND METHODS: A systematic review of the literature on ethnobotanical use and anti-BU activity of plants reported for BU treatment was performed. The approach consisted to search several resources, including Technical Reports, Books, Theses, Conference proceedings, web-based scientific databases such as publications on PubMed, Science direct, Springer, ACS, Scielo, PROTA, Google and Google scholar reporting ethnobotanical surveys and screening of natural products against Mycobacterium ulcerans. This study was limited to papers and documents published either in English or French reporting ethnopharmacological knowledge in BU treatment or pharmacological potency in vitro. This review covered the available literature up to December 2014. RESULTS: The majority of reports originated from the three most affected West African countries (Cote d'Ivoire, Ghana and Benin). Though, 98 plant species belonging to 48 families have been identified as having anti-BU use, many have received no or little attention. Most of the pharmacological studies were performed only on 54 species. To a lesser extent, ethnopharmacological knowledge was validated in vitro for only 13 species. Of those, seven species including Ricinus comminus, Cyperus cyperoides (cited as Mariscus alternifolius), Nicotiana tabacum, Mangifera indica, Solanum rugosum, Carica papaya, and Moringa oleifera demonstrated efficacy in hospitalised BU patients. Four isolated and characterized compounds were reported to have moderate bioactivity in vitro against M. ulcerans. CONCLUSIONS: This review compiles for the first time ethnopharmacologically useful plants against BU. The phamacological potential of 13 of them has been demonstrated in vitro and support BU evidence-based traditional medicines. In addition, 7 species showed activity in BU patients and have emerged as a promising source of the traditional medicine for treatment of BU. Yet, further safety and efficacy study should be initiated prior any approval as alternative therapy. Overall, a huge gap in knowledge appeared, suggesting further well-planned and detailed investigations of the in vitro, in vivo, and safety properties of the claimed anti-BU plants. Therefore, plants with medicinal potential should be scrutinized for biologically active compounds, using bioassay-guided fractionation approach to provide new insights to find novel therapeutics for BU control.


Asunto(s)
Úlcera de Buruli/tratamiento farmacológico , Preparaciones de Plantas/uso terapéutico , Plantas Medicinales/química , África Occidental , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Úlcera de Buruli/microbiología , Etnofarmacología , Humanos , Mycobacterium ulcerans/efectos de los fármacos , Mycobacterium ulcerans/aislamiento & purificación , Preparaciones de Plantas/farmacología
13.
J Wound Care ; 23(8): 417-8, 422-4, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25139600

RESUMEN

OBJECTIVE: Mycobacterium ulcerans is the causative agent of Buruli ulcer disease, the third most common mycobacteriosis after tuberculosis and leprosy and an emerging public health threat in sub-Saharan Africa. The bacteria produce a diffusible cytotoxin called mycolactone, which triggers the formation of necrotic lesions in cutaneous and subcutaneous tissues. The principal aim of this study was to characterise the cell surface hydrophobicity of Mycobacterium ulcerans and determine if bacteria bind to dialkyl carbamoyl chloride (DACC)-coated dressings through hydrophobic interactions in vitro. Since mycolactone displays hydrophobic groups, a secondary aim was to compare mycolactone binding to hydrophobic and standard dressings. METHODS: We used hydrophobic interaction chromatography to evaluate the cell surface hydrophobicity of Mycobacterium ulcerans, compared to that of other microorganisms colonising wounds. The binding of Mycobacterium ulcerans bacteria to DACC-coated and control dressings was then assessed quantitatively by measurement of microbial adenosine triphosphate (ATP), while that of mycolactone was evaluated by fluorescence spectroscopy. RESULTS: Compared to Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa, Mycobacterium ulcerans displayed the highest cell surface hydrophobicity, irrespective of the bacterial production of mycolactone. Mycobacterium ulcerans bacteria bound to DACC-coated dressings [corrected] better than untreated controls. Mycolactone did not bind stably to hydrophobic, nor standard dressings, in the conditions tested. CONCLUSION: Retention of Mycobacterium ulcerans and other wound pathogens to DACC-coated dressings may help reduce the bacterial load in Buruli ulcers and thereby improve healing. Dressings efficiently capturing mycolactone may bring an additional clinical benefit, by accelerating the elimination of the toxin during the course of antibiotic treatment.


Asunto(s)
Adhesión Bacteriana , Vendajes/microbiología , Úlcera de Buruli/microbiología , Carbamatos/administración & dosificación , Mycobacterium ulcerans/fisiología , Cicatrización de Heridas/efectos de los fármacos , Carga Bacteriana/efectos de los fármacos , Úlcera de Buruli/tratamiento farmacológico , Movimiento Celular , Escherichia coli/fisiología , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Macrólidos/metabolismo , Pseudomonas aeruginosa/fisiología , Staphylococcus aureus/fisiología
14.
Ann Dermatol Venereol ; 141(6-7): 413-8, 2014.
Artículo en Francés | MEDLINE | ID: mdl-24951139

RESUMEN

BACKGROUND: In recent years, first-line therapy for Mycobacterium ulcerans infection in French Guiana has consisted of antibiotics active against this organism. Two regimens are used comprising rifampicin associated with clarithromycin or amikacin. PATIENTS AND METHODS: We describe four patients presenting apparent worsening of their lesions during treatment: ulceration of a nodular lesion in a 32-year-old woman and worsening of an ulcerated lesion in three patients aged 16, 27 and 79 years. DISCUSSION: In these 4 patients, we concluded that the symptoms were caused by a paradoxical response or a reaction, a phenomenon already described in tuberculosis and leprosy. Such worsening is transient and must not be misinterpreted as failure to respond to treatment. The most plausible pathophysiological hypothesis involves the re-emergence of potentially necrotizing cellular immunity secondary to the loss of mycolactone, a necrotizing and immunosuppressive toxin produced by M. ulcerans, resulting from the action of the antibiotics.


Asunto(s)
Amicacina/efectos adversos , Antibacterianos/efectos adversos , Úlcera de Buruli/tratamiento farmacológico , Claritromicina/efectos adversos , Rifampin/efectos adversos , Adolescente , Adulto , Anciano , Amicacina/administración & dosificación , Amicacina/farmacología , Amicacina/uso terapéutico , Antibacterianos/administración & dosificación , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Asia/etnología , Brasil/etnología , Úlcera de Buruli/patología , Úlcera de Buruli/cirugía , Claritromicina/administración & dosificación , Claritromicina/farmacología , Claritromicina/uso terapéutico , Terapia Combinada , Desbridamiento , Quimioterapia Combinada , Europa (Continente)/etnología , Femenino , Úlcera del Pie/tratamiento farmacológico , Úlcera del Pie/etiología , Úlcera del Pie/cirugía , Guyana Francesa , Humanos , Inmunidad Celular/efectos de los fármacos , Macrólidos/metabolismo , Masculino , Mycobacterium ulcerans/efectos de los fármacos , Mycobacterium ulcerans/metabolismo , Rifampin/administración & dosificación , Rifampin/farmacología , Rifampin/uso terapéutico , Cicatrización de Heridas
15.
Open Forum Infect Dis ; 1(1): ofu021, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25734094

RESUMEN

BACKGROUND: Buruli ulcer is the third most common mycobacterial disease after tuberculosis and leprosy and is particularly frequent in rural West and Central Africa. However, the impact of HIV infection on BU severity and prevalence remains unclear. METHODS: This was a retrospective study of data collected at the Akonolinga District Hospital, Cameroon, from January 1, 2002 to March 27, 2013. Human immunodeficiency virus prevalence among BU patients was compared with regional HIV prevalence. Baseline characteristics of BU patients were compared between HIV-negative and HIV-positive patients and according to CD4 cell count strata in the latter group. Buruli ulcer time-to-healing was assessed in different CD4 count strata, and factors associated with BU main lesion size at baseline were identified. RESULTS: Human immunodeficiency virus prevalence among BU patients was significantly higher than the regional estimated prevalence in each group (children, 4.00% vs 0.68% [P < .001]; men, 17.0% vs 4.7% [P < .001]; women, 36.0% vs 8.0% [P < .001]). Individuals who were HIV positive had a more severe form of BU, with an increased severity in those with a higher level of immunosuppression. Low CD4 cell count was significantly associated with a larger main lesion size (ß-coefficient, -0.50; P = .015; 95% confidence interval [CI], -0.91-0.10). Buruli ulcer time-to-healing was more than double in patients with a CD4 cell count below 500 cell/mm(3) (hazard ratio, 2.39; P = .001; 95% CI, 1.44-3.98). CONCLUSION: Patients who are HIV positive are at higher risk for BU. Human immunodeficiency virus-induced immunosuppression seems to have an impact on BU clinical presentation and disease evolution.

16.
Pan Afr Med J ; 16: 63, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24711863

RESUMEN

INTRODUCTION: Buruli ulcer (BU) is a skin disease caused by Mycobacterium ulcerans. It is the third most common mycobacterial infection after tuberculosis and leprosy. Community Health Workers (CHWs) hold the potential to support patients and their families at the community level. METHODS: We conducted a cross-sectional descriptive study to assess the participation of CHWs in the early diagnosis and treatment of BU in Ngoantet, Cameroon. The CHWs performance was measured using: the number of cases referred to the Ngoantet Health Centre, the percentage of accomplished referrals, the percentage of cases referred by CHWs confirmed by the staff of Ngoantet Health Centre. Data was analyzed using Epi-info version 3.4.1. and Microsoft Office Excel 2003. The study focused on 51 CHWs in the Ngoantet health area. RESULTS: The referral rate was 95.0%. Most of the suspicious cases (91.5%) referred were confirmed by health workers. Most CHWs (78.4%) declared that they had identified at least one presumptive case of BU infection. CONCLUSION: We conclude that the CHWs can play a key role in scaling up BU control activities using a referral system. This study confirms the role of home visits and inspections in the early detection and treatment of BU.


Asunto(s)
Úlcera de Buruli/prevención & control , Control de Enfermedades Transmisibles/métodos , Agentes Comunitarios de Salud , Rol Profesional , Adulto , Anciano , Úlcera de Buruli/diagnóstico , Úlcera de Buruli/epidemiología , Camerún/epidemiología , Estudios Transversales , Diagnóstico Precoz , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mycobacterium ulcerans , Enfermedades Desatendidas , Derivación y Consulta/estadística & datos numéricos
17.
An. bras. dermatol ; 85(3): 281-301, jun. 2010. ilus, mapas
Artículo en Inglés, Portugués | LILACS | ID: lil-553035

RESUMEN

A úlcera de Buruli, uma doença infecciosa causada pela Mycobacterium ulcerans (M. ulcerans),é a terceira micobacteriose em ocorrência, após a hanseníase e a tuberculose. Essa micobacteriose atípica tem sido relatada em mais de 30 países, principalmente, nos que têm climas tropicais e subtropicais, mas a sua epidemiologia permanece obscura. Recentemente, os primeiros casos autóctones do Brasil foram relatados, fazendo com que dermatologistas brasileiros estejam atentos a esse diagnóstico. O quadro clínico varia: nódulos, áreas de edema, placas, mas a manifestação mais típica é uma grande úlcera, que ocorre, em geral, nas pernas ou nos braços. Apesar do amplo conhecimento quanto ao seu quadro clínico em países endêmicos, nas outras áreas, esse diagnóstico pode passar despercebido. Assim, médicos devem ser orientados quanto à úlcera de Buruli, pois o diagnóstico precoce, o tratamento específico e a introdução de cuidados na prevenção de incapacidades são essenciais para uma boa evolução.


Buruli ulcer, an infectious disease caused by Mycobacterium ulcerans, is the third most prevalent mycobacteriosis, after tuberculosis and leprosy. This atypical mycobacteriosis has been reported in over 30 countries, mainly those with tropical and subtropical climates, but its epidemiology remains unclear. The first autochthonous cases of infection in Brazil have recently been described, making this diagnosis important for Brazilian dermatologists. Clinical manifestations vary from nodules, areas of edema, and plaques, but the most typical presentation is a large ulcer, usually in the limbs. Despite considerable knowledge about its clinical manifestations in some endemic countries, in other areas the diagnosis may be overlooked. Therefore, physicians should be educated about Buruli ulcer, since early diagnosis and treatment, including measures to prevent disability, are essential for a good outcome.


Asunto(s)
Humanos , Úlcera de Buruli , Úlcera de Buruli/diagnóstico , Úlcera de Buruli/epidemiología , Úlcera de Buruli/etiología , Úlcera de Buruli/inmunología , Úlcera de Buruli/terapia
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