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Background: Previous studies have reported that presence and severity of Buruli ulcer (BU) may reflect the underlying immunosuppression in HIV infected individuals by causing increased incidence of multiple, larger and ulcerated lesions. We report cases of BU-HIV coinfection and the accompanying programmatic challenges encountered in central Ghana.Methods: Patients with PCR confirmed BU in central Ghana who were HIV positive were identified and their BU01 forms were retrieved and reviewed in further detail. A combined 16S rRNA reverse transcriptase / IS2404 qPCR assay was used to assess the Mycobacterium ulcerans load. The characteristics of coinfected patients (BU+HIV+) were compared with a group of matched controls.Results: The prevalence of HIV in this BU cohort was 2.4% (compared to national HIV prevalence of 1.7%). Eight of 9 BU+HIV+ patients had a single lesion and ulcers were the most common lesion type. The lesions presented were predominantly category II (5/9) followed by category I lesions. The median (IQR) time to healing was 14 (8-28) weeks in the BU+HIV+ compared to 28 (12-33) weeks in the control BU+HIV- group (p = 0.360). Only one BU+HIV+ developed a paradoxical reaction at week 16 but the lesion healed completely at week 20. The median bacterial load (16SrRNA) of BU+HIV+ patients was 750 copies /ml (95% CI 0-398,000) versus 500 copies/ml (95% CI 0-126,855,500) in BU+HIV- group. Similarly, the median count using the IS2404 assay was 500 copies/ml (95% CI 0-500) for BU+HIV+ patients versus 500 copies/ml (95% CI 500-31,000) for BU+HIV- patients. BU+HIV- patients mounted a significantly higher interferon-γ response compared to the BU+HIV+ co-infected patients with respective median (range) responses of [1687(81.11-4399) pg/ml] versus [137.5(4.436-1406) pg/ml, p = 0.03]. There were challenges with the integration of HIV and BU care in this cohort.Conclusion: The prevalence of HIV in the BU+ infected population was not significantly increased when compared to the prevalence of HIV in the general population. There was no clear relationship between BU lesion severity and HIV viral load or CD4 counts. Efforts should be made to encourage the integration of care of patients with BU-HIV coinfection. [ABSTRACT FROM AUTHOR]

This article discusses a severe case of Buruli ulcer disease in an 8-year-old girl from Ghana. The patient initially had a painless nodule on her chest that rapidly increased in size. After seeking medical attention, she was diagnosed with Buruli ulcer disease and started on antibiotic therapy. However, two weeks into treatment, she developed pleural effusions, which is a rare complication of the disease. The patient was successfully treated with thoracocentesis, steroid therapy, and surgical therapy. The article highlights the challenges and successes of managing Buruli ulcer disease in rural communities and discusses the phenomenon of paradoxical reactions during antibiotic therapy. [Extracted from the article]

Culture of Mycobacterium ulcerans from Buruli ulcer patients has very low sensitivity. Thus confirmation of M. ulcerans infection is primarily based on PCR directed against IS2404. In this study we compare the genotypes obtained by variable number of tandem repeat analysis of DNA from IS2404-PCR positive cultures with that obtained from IS2404 positive, culture-negative tissue. A significantly greater genetic heterogeneity was found among culture-negative samples compared with that found in cultured strains but a single genotype is over-represented in both sample sets. This study provides evidence that both the focal location of bacteria in a lesion as well as differences in the ability to culture a particular genotype may underlie the low sensitivity of culture. Though preliminary, data from this work also suggests that mycobacteria previously associated with fish disease (M. pseudoshottsii) may be pathogenic for humans. [ABSTRACT FROM AUTHOR]

Background: Mycobacterium ulcerans, the causative agent of Buruli ulcer (BU), is unique among human pathogens in its capacity to produce a polyketide-derived macrolide called mycolactone, making this molecule an attractive candidate target for diagnosis and disease monitoring. Whether mycolactone diffuses from ulcerated lesions in clinically accessible samples and is modulated by antibiotic therapy remained to be established. Methodology/Principal Finding: Peripheral blood and ulcer exudates were sampled from patients at various stages of antibiotic therapy in Ghana and Ivory Coast. Total lipids were extracted from serum, white cell pellets and ulcer exudates with organic solvents. The presence of mycolactone in these extracts was then analyzed by a recently published, field-friendly method using thin layer chromatography and fluorescence detection. This approach did not allow us to detect mycolactone accurately, because of a high background due to co-extracted human lipids. We thus used a previously established approach based on high performance liquid chromatography coupled to mass spectrometry. By this means, we could identify structurally intact mycolactone in ulcer exudates and serum of patients, and evaluate the impact of antibiotic treatment on the concentration of mycolactone. Conclusions/Significance: Our study provides the proof of concept that assays based on mycolactone detection in serum and ulcer exudates can form the basis of BU diagnostic tests. However, the identification of mycolactone required a technology that is not compatible with field conditions and point-of-care assays for mycolactone detection remain to be worked out. Notably, we found mycolactone in ulcer exudates harvested at the end of antibiotic therapy, suggesting that the toxin is eliminated by BU patients at a slow rate. Our results also indicated that mycolactone titres in the serum may reflect a positive response to antibiotics, a possibility that it will be interesting to examine further through longitudinal studies. Author Summary: Mycolactone is a diffusible cytotoxin produced by Mycobacterium ulcerans, the causative agent of the skin disease Buruli ulcer. In a previous study using animal models, we reported that mycolactone released by cutaneous foci of infection gains access to the peripheral blood. Here we investigated whether mycolactone circulates in human patients and is detectable in clinically accessible samples. Using a combination of solvent extraction, high performance liquid chromatography and mass spectrometry analysis, we found that structurally intact mycolactone was present in ulcer exudates obtained from wound swabs and in the serum of patients. Unexpectedly, high titres of mycolactone were detected in ulcer exudates after completion of antibiotic treatment. In contrast, mycolactone could only be detected in the serum of newly diagnosed patients. Our results demonstrate that mycolactone detection in serum and ulcer exudates may be used to diagnose BU. Moreover, they suggest that the kinetics of mycolactone concentration in serum may be indicative of the clinical response of patients to antibiotic therapy. [ABSTRACT FROM AUTHOR]

Background: Buruli ulcer is a neglected tropical disease caused by Mycobacterium ulcerans infection that damages the skin and subcutis. It is most prevalent in western and central Africa and Australia. Standard antimicrobial treatment with oral rifampicin 10 mg/kg plus intramuscular streptomycin 15 mg/kg once daily for 8 weeks (RS8) is highly effective, but streptomycin injections are painful and potentially harmful. We aimed to compare the efficacy and tolerability of fully oral rifampicin 10 mg/kg plus clarithromycin 15 mg/kg extended release once daily for 8 weeks (RC8) with that of RS8 for treatment of early Buruli ulcer lesions.Methods: We did an open-label, non-inferiority, randomised (1:1 with blocks of six), multicentre, phase 3 clinical trial comparing fully oral RC8 with RS8 in patients with early, limited Buruli ulcer lesions. There were four trial sites in hospitals in Ghana (Agogo, Tepa, Nkawie, Dunkwa) and one in Benin (Pobè). Participants were included if they were aged 5 years or older and had typical Buruli ulcer with no more than one lesion (caterories I and II) no larger than 10 cm in diameter. The trial was open label, and neither the investigators who took measurements of the lesions nor the attending doctors were masked to treatment assignment. The primary clinical endpoint was lesion healing (ie, full epithelialisation or stable scar) without recurrence at 52 weeks after start of antimicrobial therapy. The primary endpoint and safety were assessed in the intention-to-treat population. A sample size of 332 participants was calculated to detect inferiority of RC8 by a margin of 12%. This study was registered with ClinicalTrials.gov, NCT01659437.Findings: Between Jan 1, 2013, and Dec 31, 2017, participants were recruited to the trial. We stopped recruitment after 310 participants. Median age of participants was 14 years (IQR 10-29) and 153 (52%) were female. 297 patients had PCR-confirmed Buruli ulcer; 151 (51%) were assigned to RS8 treatment, and 146 (49%) received oral RC8 treatment. In the RS8 group, lesions healed in 144 (95%, 95% CI 91 to 98) of 151 patients, whereas lesions healed in 140 (96%, 91 to 99) of 146 patients in the RC8 group. The difference in proportion, -0·5% (-5·2 to 4·2), was not significantly greater than zero (p=0·59), showing that RC8 treatment is non-inferior to RS8 treatment for lesion healing at 52 weeks. Treatment-related adverse events were recorded in 20 (13%) patients receiving RS8 and in nine (7%) patients receiving RC8. Most adverse events were grade 1-2, but one (1%) patient receiving RS8 developed serious ototoxicity and ended treatment after 6 weeks. No patients needed surgical resection. Four patients (two in each study group) had skin grafts.Interpretation: Fully oral RC8 regimen was non-inferior to RS8 for treatment of early, limited Buruli ulcer and was associated with fewer adverse events. Therefore, we propose that fully oral RC8 should be the preferred therapy for early, limited lesions of Buruli ulcer.Funding: WHO with additional support from MAP International, American Leprosy Missions, Fondation Raoul Follereau France, Buruli ulcer Groningen Foundation, Sanofi-Pasteur, and BuruliVac. [ABSTRACT FROM AUTHOR]

During August 2010-December 2012, we conducted a study of patients in Ghana who had Buruli ulcer, caused by Mycobacterium ulcerans, and found that 23% were co-infected with Mansonella perstans nematodes; 13% of controls also had M. perstans infection. M. perstans co-infection should be considered in the diagnosis and treatment of Buruli ulcer.

Culture of Mycobacterium ulcerans from Buruli ulcer patients has very low sensitivity. Thus confirmation of M. ulcerans infection is primarily based on PCR directed against IS2404. In this study we compare the genotypes obtained by variable number of tandem repeat analysis of DNA from IS2404-PCR positive cultures with that obtained from IS2404 positive, culture-negative tissue. A significantly greater genetic heterogeneity was found among culture-negative samples compared with that found in cultured strains but a single genotype is over-represented in both sample sets. This study provides evidence that both the focal location of bacteria in a lesion as well as differences in the ability to culture a particular genotype may underlie the low sensitivity of culture. Though preliminary, data from this work also suggests that mycobacteria previously associated with fish disease (M. pseudoshottsii) may be pathogenic for humans.

Buruli ulcer, an ulcerating skin disease caused by Mycobacterium ulcerans infection, is common in tropical areas of western Africa. We determined the clinical and microbiological responses to administration of rifampin and streptomycin for 2 weeks followed by administration of rifampin and clarithromycin for 6 weeks in 43 patients with small laboratory-confirmed Buruli lesions and monitored for recurrence-free healing. Bacterial load in tissue samples before and after treatment for 6 and 12 weeks was monitored by semiquantitative culture. The success rate was 93%, and there was no recurrence after a 12-month follow-up. Eight percent had a positive culture 4 weeks after antibiotic treatment, but their lesions went on to heal. The findings indicate that rifampin and clarithromycin can replace rifampin and streptomycin for the continuation phase after rifampin and streptomycin administration for 2 weeks without any apparent loss of efficacy.