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Indian Journal of Dermatology,... 2022Background Mycetoma is widespread in Yemen; however, there are only a few documented reports on the entity from this geographical area. Methods A prospective study of...
Background Mycetoma is widespread in Yemen; however, there are only a few documented reports on the entity from this geographical area. Methods A prospective study of 184 cases of mycetoma (male 145 and female 39) from different regions of north-western Yemen was conducted between July 2000 and May 2014. Clinical profile was recorded in a standardized protocol. The diagnosis was based on clinical features, X-ray studies, examination of grains, and histopathology. Results Eumycetoma was diagnosed in 129, caused by Madurella mycetomatis in 124, Leptosphaeria senegalensis in one and pale grain fungus in four, whereas actinomycetoma occurred in 55, caused by Streptomyces somaliensis in 29, Actinomadura madurai in nine, Actinomadura pelletieri in one, and Nocardia in sixteen. Eumycetoma cases were treated with prolonged course of antifungal drugs, mostly ketoconazole, with itraconazole being used in four patients, along with excision or debulking. Results were better when antifungal drugs were given two to three months before surgery and in those who received itraconazole. Actinomycetoma cases were initially treated with co-trimoxazole monotherapy; later streptomycin was added in 30 cases. Six patients who did not show adequate improvement and two others from the start were treated with modified Welsh regimen and with good results. Limitations Identification of different causative agents was done by histopathology and could not be reconfirmed by culture. Conclusion Mycetoma is widespread in north-western Yemen with a higher incidence of eumycetoma and a majority of the cases were caused by Madurella mycetomatis. Modified Welsh regimen in actinomycetoma and itraconazole with excision in eumycetoma showed the best results.
Topics: Antifungal Agents; Female; Humans; India; Itraconazole; Madurella; Male; Mycetoma; Prospective Studies; Yemen
PubMed: 35389029
DOI: 10.25259/IJDVL_500_2021 -
PLoS Neglected Tropical Diseases Mar 2022Mycetoma is a tropical disease caused by several fungi and bacteria present in the soil. Fungal mycetoma and eumycetoma are especially challenging to treat; therefore,...
Mycetoma is a tropical disease caused by several fungi and bacteria present in the soil. Fungal mycetoma and eumycetoma are especially challenging to treat; therefore, prevention, early diagnosis, and early treatment are important, but it is also necessary to understand the geographic distribution of these pathogenic fungi. In this study, we used DNA metabarcoding methodology to identify fungal species from soil samples. Soil sampling was implemented at seven villages in an endemic area of Sennar State in Sudan in 2019, and ten sampling sites were selected in each village according to land-use conditions. In total, 70 soil samples were collected from ground surfaces, and DNA in the soil was extracted with a combined method of alkaline DNA extraction and a commercial soil DNA extraction kit. The region for universal primers was selected to be the ribosomal internal transcribed spacer one region for metabarcoding. After the second PCR for DNA library preparation, the amplicon-based DNA analysis was performed using next-generation sequencing with two sets of universal primers. A total of twelve mycetoma-causative fungal species were identified, including the prime agent, Madurella mycetomatis, and additional pathogens, Falciformispora senegalensis and Falciformispora tompkinsii, in 53 soil samples. This study demonstrated that soil DNA metabarcoding can elucidate the presence of multiple mycetoma-causative fungi, which may contribute to accurate diagnosis for patient treatment and geographical mapping.
Topics: Animals; Coleoptera; DNA; DNA Primers; DNA, Fungal; Humans; Madurella; Mycetoma; Soil; Sudan
PubMed: 35275915
DOI: 10.1371/journal.pntd.0010274 -
Medical Mycology Case Reports Mar 2022Canine eumycetoma is a rare granulomatous disease caused by dematiaceous fungi. A 2-year-old Great Dane dog had a subcutaneous mass in the right thigh that was...
Canine eumycetoma is a rare granulomatous disease caused by dematiaceous fungi. A 2-year-old Great Dane dog had a subcutaneous mass in the right thigh that was surgically removed. Grossly, numerous black-grains were visible. Histologically subcutaneous pyogranulomas were centered on myriads of pigmented fungal elements. was molecularly characterized.
PubMed: 35169536
DOI: 10.1016/j.mmcr.2022.01.007 -
PLoS Neglected Tropical Diseases Feb 2022Eumycetoma is a chronic subcutaneous neglected tropical disease that can be caused by more than 40 different fungal causative agents. The most common causative agents...
Eumycetoma is a chronic subcutaneous neglected tropical disease that can be caused by more than 40 different fungal causative agents. The most common causative agents produce black grains and belong to the fungal orders Sordariales and Pleosporales. The current antifungal agents used to treat eumycetoma are itraconazole or terbinafine, however, their cure rates are low. To find novel drugs for eumycetoma, we screened 400 diverse drug-like molecules from the Pandemic Response Box against common eumycetoma causative agents as part of the Open Source Mycetoma initiative (MycetOS). 26 compounds were able to inhibit the growth of Madurella mycetomatis, Madurella pseudomycetomatis and Madurella tropicana, 26 compounds inhibited Falciformispora senegalensis and seven inhibited growth of Medicopsis romeroi in vitro. Four compounds were able to inhibit the growth of all five species of fungi tested. They are the benzimidazole carbamates fenbendazole and carbendazim, the 8-aminoquinolone derivative tafenoquine and MMV1578570. Minimal inhibitory concentrations were then determined for the compounds active against M. mycetomatis. Compounds showing potent activity in vitro were further tested in vivo. Fenbendazole, MMV1782387, ravuconazole and olorofim were able to significantly prolong Galleria mellonella larvae survival and are promising candidates to explore in mycetoma treatment and to also serve as scaffolds for medicinal chemistry optimisation in the search for novel antifungals to treat eumycetoma.
Topics: Acetamides; Animals; Antifungal Agents; Ascomycota; Drug Discovery; Drug Evaluation, Preclinical; Fenbendazole; Madurella; Moths; Mycetoma; Neglected Diseases; Piperazines; Pyrimidines; Pyrroles; Thiazoles; Triazoles
PubMed: 35120131
DOI: 10.1371/journal.pntd.0010159 -
Medical Mycology Feb 2022Eumycetoma is a neglected tropical disease, and Madurella mycetomatis, the most common causative agent of this disease forms black grains in hosts. Melanin was...
UNLABELLED
Eumycetoma is a neglected tropical disease, and Madurella mycetomatis, the most common causative agent of this disease forms black grains in hosts. Melanin was discovered to be one of the constituents in grains. Melanins are hydrophobic, macromolecular pigments formed by oxidative polymerisation of phenolic or indolic compounds. M. mycetomatis was previously known to produce DHN-melanin and pyomelanin in vitro. These melanin was also discovered to decrease M. mycetomatis's susceptibility to antifungals itraconazole and ketoconazole in vitro. These findings, however, have not been confirmed in vivo. To discover the melanin biosynthesis pathways used by M. mycetomatis in vivo and to determine if inhibiting melanin production would increase M. mycetomatis's susceptibility to itraconazole, inhibitors targeting DHN-, DOPA- and pyomelanin were used. Treatment with DHN-melanin inhibitors tricyclazole, carpropamid, fenoxanil and DOPA-melanin inhibitor glyphosate in M. mycetomatis infected Galleria mellonella larvae resulted in presence of non-melanized grains. Our finding suggested that M. mycetomatis is able to produce DOPA-melanin in vivo. Inhibiting DHN-melanin with carpropamid in combination with the antifungal itraconazole also significantly increased larvae survival. Our results suggested that combination treatment of antifungals and melanin inhibitors can be an alternative treatment strategy that can be further explored. Since the common black-grain eumycetoma causing agents uses similar melanin biosynthesis pathways, this strategy may be applied to them and other eumycetoma causative agents.
LAY SUMMARY
Melanin protects fungi from environmental stress and antifungals. We have discovered that Madurella mycetomatis produces DHN-, pyomelanin and DOPA-melanin in vivo. Inhibiting M. mycetomatis DHN-melanin biosynthesis increases therapeutic value of the antifungal itraconazole in vivo.
Topics: Animals; Antifungal Agents; Dihydroxyphenylalanine; Itraconazole; Madurella; Mycetoma
PubMed: 35064672
DOI: 10.1093/mmy/myac003 -
Antibiotics (Basel, Switzerland) Dec 2021Larvae of the greater wax moth, , are a convenient in vivo model for assessing the activity and toxicity of antimicrobial agents and for studying the immune response to... (Review)
Review
Larvae of the greater wax moth, , are a convenient in vivo model for assessing the activity and toxicity of antimicrobial agents and for studying the immune response to pathogens and provide results similar to those from mammals. larvae are now widely used in academia and industry and their use can assist in the identification and evaluation of novel antimicrobial agents. larvae are inexpensive to purchase and house, easy to inoculate, generate results within 24-48 h and their use is not restricted by legal or ethical considerations. This review will highlight how larvae can be used to assess the efficacy of novel antimicrobial therapies (photodynamic therapy, phage therapy, metal-based drugs, triazole-amino acid hybrids) and for determining the in vivo toxicity of compounds (e.g., food preservatives, ionic liquids) and/or solvents (polysorbate 80). In addition, the disease development processes are associated with a variety of pathogens (e.g., , , , ) in mammals are also present in larvae thus providing a simple in vivo model for characterising disease progression. The use of larvae offers many advantages and can lead to an acceleration in the development of novel antimicrobials and may be a prerequisite to mammalian testing.
PubMed: 34943757
DOI: 10.3390/antibiotics10121545 -
Acta Tropica Jan 2022Mycetoma is a chronic granulomatous inflammatory disease that is caused either by bacteria or fungi. Bacterial mycetoma (actinomycetoma) can be caused by various... (Review)
Review
Mycetoma is a chronic granulomatous inflammatory disease that is caused either by bacteria or fungi. Bacterial mycetoma (actinomycetoma) can be caused by various causative agents of the genera Nocardia, Streptomyces and Actinomadura. On the other hand, fungal mycetoma (eumycetoma) is most commonly caused by causative agents belonging to the genera Madurella, Scedosporium and Falciformispora. Early and accurate diagnosis of the causative organisms can guide proper patient management and treatment. To allow rapid and accurate species identification, different molecular techniques were developed over the past decades. These techniques can be protein based (MALDI-TOF MS) as well as DNA based (Sequencing, PCR and isothermal amplification methods). In this review, we provide an overview of the different molecular techniques currently in use and identify knowledge gaps, which need to be addressed before we can implement molecular diagnostics for mycetoma in different clinical settings.
Topics: Fungi; Humans; Madurella; Mycetoma; Polymerase Chain Reaction; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
PubMed: 34687643
DOI: 10.1016/j.actatropica.2021.106205 -
Molecules (Basel, Switzerland) Jun 2021Redox-active drugs are the mainstay of parasite chemotherapy. To assess their repurposing potential for eumycetoma, we have tested a set of nitroheterocycles and...
Redox-active drugs are the mainstay of parasite chemotherapy. To assess their repurposing potential for eumycetoma, we have tested a set of nitroheterocycles and peroxides in vitro against two isolates of , the main causative agent of eumycetoma in Sudan. All the tested compounds were inactive except for niclosamide, which had minimal inhibitory concentrations of around 1 µg/mL. Further tests with niclosamide and niclosamide ethanolamine demonstrated in vitro activity not only against but also against spp., causative agents of actinomycetoma, with minimal inhibitory concentrations below 1 µg/mL. The experimental compound MMV665807, a related salicylanilide without a nitro group, was as active as niclosamide, indicating that the antimycetomal action of niclosamide is independent of its redox chemistry (which is in agreement with the complete lack of activity in all other nitroheterocyclic drugs tested). Based on these results, we propose to further evaluate the salicylanilides, niclosamidein particular, as drug repurposing candidates for mycetoma.
Topics: Actinomadura; Animals; Humans; Madurella; Mycetoma; Niclosamide
PubMed: 34209118
DOI: 10.3390/molecules26134005 -
Antimicrobial Agents and Chemotherapy Aug 2021For many fungal infections, susceptibility testing is used to predict if an isolate is resistant or susceptible to the antifungal agent used to treat the infection. For...
For many fungal infections, susceptibility testing is used to predict if an isolate is resistant or susceptible to the antifungal agent used to treat the infection. For Madurella mycetomatis, the main causative agent of mycetoma, susceptibility testing currently is not performed on a routine basis. The current susceptibility testing method is labor-intensive, and sonication must be done to generate a hyphal inoculum. For endpoint visualization, expensive viability dyes are needed. Here, we investigated if the currently used susceptibility method could be adapted to make it amendable for use in a routine setting which can be used in low-income countries, where mycetoma is endemic. First, we developed a methodology in which hyphal fragments can be generated without the need for sonication, by comparing different bead beating methodologies. Next, susceptibility was assessed using standard broth microdilution assays as well as disc diffusion, Etest, and VIPcheck methodologies. We demonstrate that after a hyphal suspension is generated by glass bead beating, disc diffusion, Etest, and VIPcheck can be used to determine susceptibility of Madurella mycetomatis to itraconazole, posaconazole, and voriconazole. The MICs found with Etest were comparable to those obtained with our modified CLSI-based broth microdilution susceptibility assay for itraconazole and posaconazole. Furthermore, we found an inverse relationship between the zones of inhibition and MICs obtained with the Etest and those obtained by the modified CLSI broth microdilution technique.
Topics: Antifungal Agents; Disk Diffusion Antimicrobial Tests; Itraconazole; Madurella; Microbial Sensitivity Tests; Triazoles; Voriconazole
PubMed: 34181477
DOI: 10.1128/AAC.00433-21 -
PLoS Neglected Tropical Diseases Jun 2021Mycetoma is a devastating neglected tropical infection of the subcutaneous tissue and most commonly caused by the fungus Madurella mycetomatis. Treatment of mycetoma...
Mycetoma is a devastating neglected tropical infection of the subcutaneous tissue and most commonly caused by the fungus Madurella mycetomatis. Treatment of mycetoma consists of a combination of a long term antifungal treatment with itraconazole and surgery. However, treatment is associated with low success rates. Therefore, there is a need to identify novel treatments for mycetoma. CIN-102 is a synthetic partial copy of cinnamon oils with activity against many pathogenic bacteria and fungi. In this study we determined the in vitro activity of CIN-102 against 21 M. mycetomatis isolates and its in vivo efficacy in a M. mycetomatis infected Galleria mellonella larval model. In vitro, CIN-102 was active against M. mycetomatis with MICs ranging from 32 μg/mL to 512 μg/mL. 128 μg/mL was needed to inhibit the growth in 50% of tested isolates. In vivo, concentrations below the MIC of 40 mg/kg and 80 mg/kg CIN-102 prolonged larval survival, but higher concentrations of CIN-102 did not.
Topics: Animals; Antifungal Agents; Benzoates; Cinnamates; Cinnamomum zeylanicum; Drug Combinations; Drug Synergism; Humans; Larva; Madurella; Microbial Sensitivity Tests; Moths; Mycetoma; Terpenes
PubMed: 34106933
DOI: 10.1371/journal.pntd.0009488