The performance and costs of XTT, resazurin, MTS and luciferin as viability dyes in in vitro susceptibility testing of Madurella mycetomatis.

BACKGROUND: in vitro susceptibility testing for the non-sporulating fungus Madurella mycetomatis is performed with a hyphal suspension as starting inoculum and a viability dye for endpoint reading. Here we compared the performance of four different viability dyes for their use in in vitro susceptibility testing of M. mycetomatis. METHODS: To compare the reproducibility and the agreement between the viability dyes 2,3-bis-(2-methoxy-4-nitro-5-sulfphenyl)-2H-tetrazolium-5-carboxanilide salt (XTT), resazurin, 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium salt (MTS) and luciferin, the in vitro susceptibilities of 14 genetically diverse M. mycetomatis isolates were determined for itraconazole and amphotericin B. The reproducibility, agreement, price and ease of use were compared. RESULTS: Each of the four dyes gave highly reproducible results with >85.7% reproducibility. Percentage agreement ranged between 78.9% and 92.9%. Resazurin was the most economical to use (0.0009 €/minimal inhibitory concentration [MIC]) and could be followed in real time. Luciferin omitted the need to transfer the supernatant to a new 96-well plate, but cost 6.07 €/MIC. CONCLUSION: All four viability dyes were suitable to determine the in vitro susceptibility of M. mycetomatis against itraconazole and amphotericin B. Based on the high reproducibility, high percentage agreement, price and possibility to monitor in real time, resazurin was the most suited for routine in vitro susceptibility testing in the diagnostic laboratory in mycetoma-endemic countries. Because luminescence could be measured directly without the need to transfer the supernatant to a new 96-well plate, luciferin is suitable for drug-screening campaigns. LAY SUMMARY: To determine the in vitro susceptibility testing in the non-sporulating fungus Madurella mycetomatis, a viability dye is needed for endpoint reading. In this study we tested the viability dyes XTT, resazurin, MTS and luciferin for their use in in vitro susceptibility testing. It appeared that they all could be used but there were differences in time to result and costs associated with them.

An updated list of eumycetoma causative agents and their differences in grain formation and treatment response.

SUMMARYIn 2023, the World Health Organization designated eumycetoma causative agents as high-priority pathogens on its list of fungal priority pathogens. Despite this recognition, a comprehensive understanding of these causative agents is lacking, and potential variations in clinical manifestations or therapeutic responses remain unclear. In this review, 12,379 eumycetoma cases were reviewed. In total, 69 different fungal species were identified as causative agents. However, some were only identified once, and there was no supporting evidence that they were indeed present in the grain. Madurella mycetomatis was by far the most commonly reported fungal causative agent. In most studies, identification of the fungus at the species level was based on culture or histology, which was prone to misidentifications. The newly used molecular identification tools identified new causative agents. Clinically, no differences were reported in the appearance of the lesion, but variations in mycetoma grain formation and antifungal susceptibility were observed. Although attempts were made to explore the differences in clinical outcomes based on antifungal susceptibility, the lack of large clinical trials and the inclusion of surgery as standard treatment posed challenges in drawing definitive conclusions. Limited case series suggested that eumycetoma cases caused by Fusarium species were less responsive to treatment than those caused by Madurella mycetomatis. However, further research is imperative for a comprehensive understanding.

Protoplast-mediated transformation of Madurella mycetomatis using hygromycin resistance as a selection marker.

Madurella mycetomatis is the main cause of mycetoma, a chronic granulomatous infection for which currently no adequate therapy is available. To improve therapy, more knowledge on a molecular level is required to understand how M. mycetomatis is able to cause this disease. However, the genetic toolbox for M. mycetomatis is limited. To date, no method is available to genetically modify M. mycetomatis. In this paper, a protoplast-mediated transformation protocol was successfully developed for this fungal species, using hygromycin as a selection marker. Furthermore, using this method, a cytoplasmic-GFP-expressing M. mycetomatis strain was created. The reported methodology will be invaluable to explore the pathogenicity of M. mycetomatis and to develop reporter strains which can be useful in drug discovery as well as in genetic studies.

Complete Genome Sequence of the Itraconazole Decreased Susceptible Madurella fahalii Type-Strain CBS 129176.

Madurella fahalii is a causative agent of the implantation mycosis mycetoma with decreased susceptibility to itraconazole, the preferred therapeutic drug to combat mycetoma. Here, we report the M. fahalii type-strain CBS 129176 genome assembly and annotation to identify a glutamic acid insert near the azole-binding pocket in the Cyp51A protein.

Using (1,3)-ß-D-glucan concentrations in serum to monitor the response of azole therapy in patients with eumycetoma caused by Madurella mycetomatis.

INTRODUCTION: (1,3)-ß-D-glucan is a panfungal biomarker secreted by many fungi, including Madurella mycetomatis, the main causative agent of eumycetoma. Previously we demonstrated that (1,3)-ß-D-glucan was present in serum of patients with eumycetoma. However, the use of (1,3)-ß-D-glucan to monitor treatment responses in patients with eumycetoma has not been evaluated. MATERIALS AND METHODS: In this study, we measured (1,3)-ß-D-glucan concentrations in serum with the WAKO (1,3)-ß-D-glucan assay in 104 patients with eumycetoma treated with either 400 mg itraconazole daily, or 200 mg or 300 mg fosravuconazole weekly. Serial serum (1,3)-ß-D-glucan concentrations were measured at seven different timepoints. Any correlation between initial and final (1,3)-ß-D-glucan concentrations and clinical outcome was evaluated. RESULTS: The concentration of (1,3)-ß-D-glucan was obtained in a total of 654 serum samples. Before treatment, the average (1,3)-ß-D-glucan concentration was 22.86 pg/mL. During the first 6 months of treatment, this concentration remained stable. (1,3)-ß-D-glucan concentrations significantly dropped after surgery to 8.56 pg/mL. After treatment was stopped, there was clinical evidence of recurrence in 18 patients. Seven of these 18 patients had a (1,3)-ß-D-glucan concentration above the 5.5 pg/mL cut-off value for positivity, while in the remaining 11 patients, (1,3)-ß-D-glucan concentrations were below the cut-off value. This resulted in a sensitivity of 38.9% and specificity of 75.0%. A correlation between lesion size and (1,3)-ß-D-glucan concentration was noted. CONCLUSION: Although in general (1,3)-ß-D-glucan concentrations can be measured in the serum of patients with eumycetoma during treatment, a sharp decrease in ß-glucan concentration was only noted after surgery and not during or after antimicrobial treatment. (1,3)-ß-D-glucan concentrations were not predictive for recurrence and seem to have no value in determining treatment response to azoles in patients with eumycetoma.

The combination of manogepix and itraconazole is synergistic and inhibits the growth of Madurella mycetomatis in vitro but not in vivo.

Mycetoma is a neglected tropical disease commonly caused by the fungus Madurella mycetomatis. Standard treatment consists of extensive treatment with itraconazole in combination with surgical excision of the infected tissue, but has a low success rate. To improve treatment outcomes, novel treatment strategies are needed. Here, we determined the potential of manogepix, a novel antifungal agent that targets the GPI-anchor biosynthesis pathway by inhibition of the GWT1 enzyme. Manogepix was evaluated by determining the minimal inhibitory concentrations (MICs) according to the CLSI-based in vitro susceptibility assay for 22 M. mycetomatis strains and by in silico protein comparison of the target protein. The synergy between manogepix and itraconazole was determined using a checkerboard assay. The efficacy of clinically relevant dosages was assessed in an in vivo grain model in Galleria mellonella larvae. MICs for manogepix ranged from <0.008 to >8 mg/l and 16/22 M. mycetomatis strains had an MIC ≥4 mg/ml. Differences in MICs were not related to differences observed in the GWT1 protein sequence. For 70% of the tested isolates, synergism was found between manogepix and itraconazole in vitro. In vivo, enhanced survival was not observed upon admission of 8.6 mg/kg manogepix, nor in combination treatment with 5.7 mg/kg itraconazole. MICs of manogepix were high, but the in vitro antifungal activity of itraconazole was enhanced in combination therapy. However, no efficacy of manogepix was found in an in vivo grain model using clinically relevant dosages. Therefore, the therapeutic potential of manogepix in mycetoma caused by M. mycetomatis seems limited.

Treatment of Madurella mycetomatis-caused mycetoma consists of extensive exposure to antifungals and surgery. To improve therapy, we evaluated manogepix, a novel antifungal agent, as a therapeutic option against M. mycetomatis. Our findings suggest limited therapeutic potential for manogepix.

A Falciformispora senegalensis grain model in Galleria mellonella larvae.

Eumycetoma is a subcutaneous implantation mycosis often found in the foot. One of the hallmarks of eumycetoma is the formation of grains. These grains are either black or white, and the consistency and morphology differs per causative agent. The two most common causative agents of black-grain eumycetoma are Madurella mycetomatis and Falciformispora senegalensis. Since grains cannot be formed in vitro, in vivo models are needed to study grain formation. Here, we used the invertebrate Galleria mellonella to establish an in vivo grain model for F. senegalensis. Three different F. senegalensis strains were selected, and four different inocula were used to infect G. mellonella larvae, ranging from 0.04 mg/larvae to 10 mg/larvae. Larval survival was monitored for 10 days. Grain formation was studied macroscopically and histologically. The efficacy of antifungal therapy was determined for itraconazole, amphotericin B, and terbinafine. A concentration of 10 mg F. senegalensis per larva was lethal for the majority of the larvae within 10 days. At this inoculum, grains were formed within 24 h after infection. The grains produced in the larvae resembled those formed in human patients. Amphotericin B given at 1 mg/kg 4 h, 28 h, and 52 h after infection prolonged larval survival. No enhanced survival was noted for itraconazole or terbinafine. In conclusion, we developed a F. senegalensis grain model in G. mellonella larvae in which grains were formed that were similar to those formed in patients. This model can be used to monitor grain formation over time and study antifungal efficacy.

Within eumycetoma lesions, the causative agents are embedded in grains. However, the grains differ per causative agent. In this study, we developed a grain model of Falciformispora senegalensis in the larvae of Galleria mellonella. This model can be used in the future to study the efficacy of novel antifungal agents.

The First Case of Fusarium falciforme Eumycetoma in Sudan and an Extensive Literature Review about Treatment Worldwide.

Eumycetoma is an infectious disease caused by various fungal pathogens. The disease is characterised by black and pale-yellowish grain discharge. In this communication, we report a case of eumycetoma with a pale grain foot-eumycetoma caused by Fusarium falciforme. The patient presented at the outpatient clinic of the Mycetoma Research Centre in Sudan. The causative agent was initially misidentified as Aspergillus nidulans based on its seemingly similar histopathological appearance. However, sequencing the internally transcribed spacer region of the extracted grain confirmed infection with Fusarium falciforme. Although the patient received Itraconazole and underwent surgical excision, the disease was recurrent. To our knowledge, this is the first report on Fusarium falciforme causing eumycetoma in Sudan, indicating the expansion of the geographical distribution of this pathogen. This calls for raising the awareness of healthcare providers and improving the diagnostic and surveillance systems in at-risk areas to improve the case management and reduce the threat of further spread. Considering the potential impacts of F. falciforme infection including threatening the global health, food security, and ecosystem balance, as well as loss of biodiversity and negative socioeconomic changes in endemic countries, we recommend the implementation of an integrated transdisciplinary One Health strategy for the prevention and control of emerging infectious diseases including F. falciforme.

An update on the development of novel antifungal agents for eumycetoma.

Eumycetoma, a chronic subcutaneous mycosis, responds poorly to the available antifungal treatments and patients often require extensive surgical resection or amputation of the affected limb. More effective treatments are needed for eumycetoma. This article will describe some of the approaches being used to develop and evaluate new treatments for eumycetoma, summarise the latest developments and discuss the challenges that lie ahead.

Evaluation of the Antiparasitic and Antifungal Activities of Synthetic Piperlongumine-Type Cinnamide Derivatives: Booster Effect by Halogen Substituents.

A series of synthetic N-acylpyrrolidone and -piperidone derivatives of the natural alkaloid piperlongumine were prepared and tested for their activities against Leishmania major and Toxoplasma gondii parasites. Replacement of one of the aryl meta-methoxy groups by halogens such as chlorine, bromine and iodine led to distinctly increased antiparasitic activities. For instance, the new bromo- and iodo-substituted compounds 3 b/c and 4 b/c showed strong activity against L. major promastigotes (IC50 =4.5-5.8 µM). Their activities against L. major amastigotes were moderate. In addition, the new compounds 3 b, 3 c, and 4 a-c exhibited high activity against T. gondii parasites (IC50 =2.0-3.5 µM) with considerable selectivities when taking their effects on non-malignant Vero cells into account. Notable antitrypanosomal activity against Trypanosoma brucei was also found for 4 b. Antifungal activity against Madurella mycetomatis was observed for compound 4 c at higher doses. Quantitative structure-activity relationship (QSAR) studies were carried out, and docking calculations of test compounds bound to tubulin revealed binding differences between the 2-pyrrolidone and 2-piperidone derivatives. Microtubules-destabilizing effects were observed for 4 b in T. b. brucei cells.

Antifungal Activity of Natural Naphthoquinones and Anthraquinones against Madurella mycetomatis.

Eumycetoma, the fungal form of the neglected tropical disease mycetoma, is a crippling infectious disease with low response rates to currently available antifungal drugs. In this study, a series of natural naphthoquinones and anthraquinones was evaluated for their activity against Madurella mycetomatis, which is the most common causative agent of eumycetoma. The metabolic activity of Madurella mycetomatis as well as the viability of Galleria mellonella larvae upon treatment with quinones was investigated. Several hydroxy-substituted naphthoquinones exhibited activity against Madurella mycetomatis. In particular, naphthazarin (5,8-dihydroxy-1,4-naphthoquinone) was identified as a considerably active antifungal compound against Madurella mycetomatis (IC50 =1.4 µM), while it showed reduced toxicity to Galleria mellonella larvae, which is a well-established in vivo invertebrate model for mycetoma drug studies.

Using a Madurella mycetomatis-specific PCR on grains obtained via non-invasive fine-needle aspirated material is more accurate than cytology.

BACKGROUND: Eumycetoma is a chronic subcutaneous inflammatory fungal infection most often caused by the fungus Madurella mycetomatis. Using a species-specific PCR on DNA directly isolated from grains is currently the most reliable method for species identification. However, so far, PCR has been performed on grains obtained through deep-seated surgical biopsies, which are invasive procedures. Grains can also be obtained via ultrasound-guided fine-needle aspiration (US-FNA). Here we determined the diagnostic performance of species-specific PCRs performed on samples obtained through US-FNA. METHODS: From 63 patients, US-FNA was performed to obtain eumycetoma grains; 34 patients also underwent a deep-seated biopsy. From the grains, DNA was isolated, and one pan-fungal and two M. mycetomatis-specific PCRs were performed. The sensitivity and specificity were determined. RESULTS: Of the 63 patients who underwent US-FNA, 78% (49/63) had evidence of eumycetoma based on cytology and 93.7% (59/63) based on species-specific PCRs. In the 34 patients for whom surgical biopsies were performed as well, 31 patients had a positive PCR for M. mycetomatis when DNA was isolated from the deep-seated biopsy, and 30 had a positive PCR when DNA was obtained from the US-FNA material. This resulted in a 96.8% sensitivity, and 100% specificity with 97.1% diagnostic accuracy for PCR performed on US-FNA. CONCLUSION: PCR performed on the US-FNA material has a similar sensitivity and specificity as PCR performed on deep-seated biopsies. Therefore, when using PCR, a deep-seated biopsy may not be necessary to obtain grains.

Comparing the performance of the common used eumycetoma diagnostic tests.

OBJECTIVES: Mycetoma is a neglected tropical implantation disease caused by 70 different infectious agents. Identifying the causative organism to the species level is essential for appropriate patient management. Ultrasound, histopathology, culture and two species-specific PCRs are most the commonly used methods for species identification in endemic regions. The aim of this study was to compare the diagnostic performance of these commonly used assays using sequencing of barcoding genes as the gold standard. METHODS: This descriptive cross-sectional study was conducted at the Mycetoma Research Centre, University of Khartoum, Sudan. It included 222 patients suspected of fungal mycetoma caused by Madurella mycetomatis. RESULTS: 154 (69.3%) were correctly identified by ultrasound, histology, culture and both species-specific PCRs. In 60 patients, at least one of the diagnostic tests failed to identify M. mycetomatis. Five patients had no evidence of eumycetoma, and for three, only the ultrasound was indicative of mycetoma. The two species-specific PCRs were the most sensitive and specific methods, followed by culture and histology. Ultrasound was the least specific as it only allowed differentiation between actinomycetoma and eumycetoma. The time to result was 9.38 minutes for ultrasound, 3.76 hours for PCR, 8.5 days for histopathology and 21 days for grain culturing. CONCLUSION: Currently, PCR directly on DNA isolated from grains is the most rapid and reliable diagnostic tool to identify M. mycetomatis eumycetoma.

Wako ß-D-glucan assay can be used to measure serum ß-D-glucan in Sudanese patients to aid with diagnosis of eumycetoma caused by Madurella mycetomatis.

BACKGROUND: Eumycetoma is a neglected tropical infection of the subcutaneous tissue commonly caused by the fungus Madurella mycetomatis. Previously, we demonstrated that ß-D-glucan was present in the serum of eumycetoma patients. OBJECTIVE: To compare the performance of the recently approved easy-to-use Wako ß-D-glucan assay to that of the Fungitell assay in eumycetoma patients. METHODS: Using sera obtained from 41 eumycetoma, 12 actinomycetoma and 29 healthy endemic controls, we measured the ß-glucan serum concentrations using the Wako assay and compared the performance to that of the Fungitell assay. RESULTS: With the Fungitell assay, median ß-glucan serum concentrations of 208, 70 and 27 pg/ml were obtained for the 41 eumycetoma patients, the 12 actinomycetoma patients and the 29 healthy endemic controls, respectively. With the Wako assay these concentrations were 14.45, 11.57 and 2.5 pg/ml, respectively. We demonstrated that when using the optimized cut-off value (5.5 pg/ml) for the Wako assay, the Wako and Fungitell assays had comparable performance in terms of sensitivity and specificity. CONCLUSION: The Wako assay is comparable to the Fungitell assay for measurement of serum ß-glucan in mycetoma patients and hence can be used in combination with current diagnostic tools. However, this test should be used in combination with other tests to differentiate actinomycetoma from eumycetoma.

Diagnostics to support mycetoma management-Development of two target product profiles.

OBJECTIVE: Mycetoma is a neglected tropical disease caused by more than 70 different microorganisms and identified by the WHO as one of the high-priority diseases for developing diagnostic tests. To ensure the production of diagnostic assays for use by clinical staff in endemic regions, target product profiles (TPPs) were designed. METHODS: We describe the development of two TPPs: one for a diagnostic test able to identify the causative agent of mycetoma and another that would determine when treatment could be stopped. The TPPs were developed by considering product use, design, performance, product configuration and costs. RESULTS: Version 1.0 TPPs for two uses were posted by WHO for a 1-month online public consultation on 25 October 2021, and the final TPP was posted online on 5 May 2022. CONCLUSION: A major difficulty encountered in developing both TPPs was the large number of agents able to cause mycetoma and the lack of specific biomarkers for most of them.

Staphylococcus aureus causing primary foot botryomycosis mimicking actinomycetoma: a case report from Sudan.

OBJECTIVES: Botryomycosis is a rare chronic granulomatous inflammatory disease of bacterial origin. Two forms of the disease exist; the cutaneous and the visceral form. The subcutaneous form mimics actinomycetoma clinically and histologically; however, the treatment is different. In this communication, we report on a Sudanese male patient who presented with foot botryomycosis. DESIGN: Case report. RESULTS: The patient was initially diagnosed with actinomycetoma by the presence of Streptomyces somaliensis like-grains in the histological slides. The patient was treated with a combination of co-trimoxazole and amikacin sulfate and shifted after 1 year to co-trimoxazole, amoxicillin, and clavulanic acid. Despite treatment, the infection progressed, and the bone was invaded. The infected limb was amputated. The histopathological report of the surgical biopsy showed gram-positive cocci inside the grain. The 16S sequence identified these cocci as Staphylococcus aureus. CONCLUSION: This is the first reported botryomycosis case from Sudan, and it highlights why molecular identification is vital in diagnosis.

Encapsulated eumycetoma caused by Biatriospora mackinnonii.

Eumycetoma is a chronic infection due to filamentous fungi. Herein, we report a case of eumycetoma presenting as a subcutaneous encapsulated lesion on the right leg with no previous traumatic implantation. From microscopic morphological characteristics and molecular analysis, the pathogenic fungal species were identified as Biatriospora mackinnonii. Surgical excision of the entire lesion was performed to reduce the fungal load and improve antifungal therapy response.

Epidemiological cut-off values for itraconazole and ravuconazole for Madurella mycetomatis, the most common causative agent of mycetoma.

BACKGROUND: Eumycetoma is a neglected tropical disease. It is a chronic inflammatory subcutaneous infection characterised by painless swellings which produce grains. It is currently treated with a combination of itraconazole and surgery. In an ongoing clinical study, the efficacy of fosravuconazole, the prodrug of ravuconazole, is being investigated. For both itraconazole and ravuconazole, no clinical breakpoints or epidemiological cut-off values (ECV) to guide treatment are currently available. OBJECTIVE: To determine tentative ECVs for itraconazole and ravuconazole in Madurella mycetomatis, the main causative agent of eumycetoma. MATERIALS AND METHODS: Minimal inhibitory concentrations (MICs) for itraconazole and ravuconazole were determined in 131 genetically diverse clinical M. mycetomatis isolates with the modified CLSI M38 broth microdilution method. The MIC distributions were established and used to determine ECVs with the ECOFFinder software. CYP51A sequences were sequenced to determine whether mutations occurred in this azole target gene, and comparisons were made between the different CYP51A variants and the MIC distributions. RESULTS: The MICs ranged from 0.008 to 1 mg/L for itraconazole and from 0.002 to 0.125 mg/L for ravuconazole. The M. mycetomatis ECV for itraconazole was 1 mg/L and for ravuconazole 0.064 mg/L. In the wild-type population, two CYP51A variants were found for M. mycetomatis, which differed in one amino acid at position 499 (S499G). The MIC distributions for itraconazole and ravuconazole were similar between the two variants. No mutations linked to decreased susceptibility were found. CONCLUSION: The proposed M. mycetomatis ECV for itraconazole is 1 mg/L and for ravuconazole 0.064 mg/L.

Madurella mycetomatis grains within a eumycetoma lesion are clonal.

Eumycetoma is a neglected tropical infection of the subcutaneous tissue, characterized by tumor-like lesions and most commonly caused by the fungus Madurella mycetomatis. In the tissue, M. mycetomatis organizes itself in grains, and within a single lesion, thousands of grains can be present. The current hypothesis is that all these grains originate from a single causative agent, however, this hypothesis was never proven. Here, we used our recently developed MmySTR assay, a highly discriminative typing method, to determine the genotypes of multiple grains within a single lesion. Multiple grains from surgical lesions obtained from 11 patients were isolated and genotyped using the MmySTR panel. Within a single lesion, all tested grains shared the same genotype. Only in one single grain from one patient, a difference of one repeat unit in one MmySTR marker was noted relative to the other grains from that patient. We conclude that within these lesions the grains originate from a single clone and that the inherent unstable nature of the microsatellite markers may lead to small genotypic differences. LAY ABSTRACT: In lesions of the implantation mycosis mycetoma many Madurella mycetomatis grains are noted. It was unknown if grains arose after implantation of a single isolate or a mixture of genetically diverse isolates. By typing the mycetoma grains we showed that all grains within a single lesion were clonal and originated from a single isolate.

Identifying novel drugs with new modes of action for neglected tropical fungal skin diseases (fungal skinNTDs) using an Open Source Drug discovery approach.

INTRODUCTION: The three fungal skin neglected tropical diseases (NTD) - mycetoma, chromoblastomycosis and sporotrichosis - currently lack prioritization and support to establish drug discovery programs in search for novel treatment options. This has made the efforts to identify novel drugs for these fragmented skinNTDs. AREAS COVERED: To help escalate the discovery of novel drugs to treat these fungal skinNTDs, the authors have prepared an overview of the compounds with activity against fungal skinNTDs by analyzing data from individual drug discovery studies, including those performed on the Medicines for Malaria Venture (MMV) open access boxes. EXPERT OPINION: The authors were unable to identify studies in which causative agents of all three skinNTDs were included, indicating that an integrated approach is currently lacking. From current available data, the azoles and iodoquinol were the only compounds with activity against causative agents from the three different fungal skinNTDs. Fungal melanin inhibition enhanced the activity of antifungal agents. For mycetoma, the fenarimols, aminothiazoles and benzimidazole carbamates are currently being investigated in the MycetOS initiative. To come to a more integrated approach to identify drugs active against all three fungal skinNTDs, compounds made in the MycetOS initiative could also be explored for chromoblastomycosis and sporotrichosis.