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.

Naphthylisoquinoline alkaloids: novel agents against the causative pathogens of eumycetoma and actinomycetoma-en route to broad-spectrum antimycetomal drugs.

Mycetoma is a devastating neglected tropical infection of the subcutaneous tissues. It is caused by fungal and bacterial pathogens recognized as eumycetoma and actinomycetoma, respectively. Mycetoma treatment involves diagnosing the causative microorganism as a prerequisite to prescribing a proper medication. Current therapy of fungal eumycetoma causative agents, such as Madurella mycetomatis, consists of long-term antifungal medication with itraconazole followed by surgery, yet with usually unsatisfactory clinical outcomes. Actinomycetoma, on the contrary, usually responds to treatment with co-trimoxazole and amikacin. Therefore, there is a pressing need to discover novel broad-spectrum antimicrobial agents to circumvent the time-consuming and costly diagnosis. Using the resazurin assay, a series of 23 naphthylisoquinoline (NIQ) alkaloids and related naphthoquinones were subjected to in vitro screening against two fungal strains of M. mycetomatis and three bacterial strains of Actinomadura madurae and A. syzygii. Seven NIQs, mostly dimers, showed promising in vitro activities against at least one strain of the mycetoma-causative pathogens, while the naphthoquinones did not show any activity. A synthetic NIQ dimer, 8,8'''-O,O-dimethylmichellamine A (18), inhibited all tested fungal and bacterial strains (IC50 = 2.81-12.07 µg/mL). One of the dimeric NIQs, michellamine B (14), inhibited a strain of M. mycetomatis and significantly enhanced the survival rate of Galleria mellonella larvae infected with M. mycetomatis at concentrations of 1 and 4 µg/mL, without being toxic to the uninfected larvae. As a result, broad-spectrum dimeric NIQs like 14 and 18 with antimicrobial activity are considered hit compounds that could be worth further optimization to develop novel lead antimycetomal agents.

Clinical features and antifungal treatment of invasive Scedosporium boydii infection: report of a case and literature overview.

OBJECTIVE: This study aims to present a case of persistent mycetoma caused by Scedosporium boydii and undertake a systematic literature overview to elucidate the clinical characteristics and antifungal treatment exhibited by such patients. METHODS: We report the case of a 24-year-old female who sustained a Scedosporium boydii infection in her right foot over a decade ago following a nail puncture. Concurrently, a comprehensive literature overview was conducted on PubMed, focusing on documented cases of Scedosporium boydii infections with the intent of extracting relevant clinical data. RESULTS: Our analysis revealed that post-transplantation, trauma, near drowning, corticosteroid administration, and prior surgical history were the main risk factors for Scedosporium boydii infection. Prevalent infection sites included skin/bone tissues, the central nervous system, and ocular regions. Among the 49 patients identified, 24 received itraconazole therapy and 25 received voriconazole, with no significant difference in patient outcomes (P = 0.158). Of these, 12 patients experienced treatment failure. Notably, prolonged antifungal treatment duration was identified as a protective factor against mortality in Scedosporium boydii infections [P = 0.022, OR(95%CI): 0.972(0.949-0.996)]. Conversely, a history of post-transplantation emerged as a potential risk factor for mortality[P = 0.046, OR(95%CI): 7.017(1.034-47.636)]. CONCLUSION: While uncommon, Scedosporium boydii infections carry a significant burden of morbidity and adverse outcomes. Heightened clinical vigilance is warranted in individuals presenting with risk factors for this pathogen. Timely and effective antifungal intervention is crucial, with both voriconazole and itraconazole demonstrating positive treatment outcomes for Scedosporium boydii infection. Therefore, prioritizing these antifungal agents should be considered a key therapeutic strategy in the management of this patient population.

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.

Tropicoporus tropicalis: A Newly Recognised Pathogen in Eumycetoma and Refractory Mycoses in Humans.

Tropicoporus tropicalis (formerly Phellinus tropicalis) is a saprophytic basidiomycete that has been implicated in refractory mycoses in humans, particularly in patients with chronic granulomatous disease. Despite its clinical significance, T. tropicalis is an under-recognised cause of eumycetoma, with no prior reports available. We present a case of white grain eumycetoma with associated osteomyelitis of the left foot, caused by T. tropicalis, confirmed through 18S-ITS1-5.8S-ITS2-28S rRNA gene amplification and sequencing. The patient was treated with itraconazole 200 mg daily, leading to gradual improvement. A review of the literature on T. tropicalis infections in humans reveals its characteristic manifestations, which include osteomyelitis, soft tissue abscesses, pulmonary nodules and keratitis. These infections are locally destructive but have the potential to disseminate. Diagnosis is often delayed and relies on molecular techniques. Amphotericin B combined with an azole appears to be the most effective treatment, often necessitating concurrent surgical drainage. In conclusion, T. tropicalis is a newly recognised pathogen associated with eumycetoma and poses an increased risk of osteomyelitis. Molecular identification, such as sequencing the internal transcribed spacer (ITS) region from cultures or tissue specimens, is crucial for accurate identification of this pathogen.

Novel Compound MMV1804559 from the Global Health Priority Box Exhibits In Vitro and In Vivo Activity against Madurella mycetomatis.

OBJECTIVES: Eumycetoma is a neglected tropical disease (NTD) characterized by subcutaneous lesions and the formation of grains. Attempts to treat eumycetoma involve a combination of antifungal treatment and surgery, although the outcome is frequently disappointing. Therefore, there is a need to identify novel antifungal drugs to treat eumycetoma. In this respect, Medicines for Malaria Venture (MMV) has assembled libraries of compounds for researchers to use in drug discovery research against NTD. Therefore, we screened two MMVOpen compound libraries to identify novel leads for eumycetoma. METHODS: A total of 400 compounds from the COVID Box and the Global Health Priority Box were screened in vitro at 100 µM and 25 µM against the most common causative agents of eumycetoma, namely Madurella mycetomatis and Falciformispora senegalensis, and the resulting IC50 and MIC50 values were obtained. Compounds with an IC50 < 8 µM were identified for possible in vivo efficacy studies using an M. mycetomatis grain model in Galleria mellonella larvae. RESULTS: Out of the 400 compounds, 22 were able to inhibit both M. mycetomatis and F. senegalensis growth at 100 µM and 25 µM, with compounds MMV1593278, MMV020335, and MMV1804559 being selected for in vivo testing. Of these three, only the pyrazolopyrimidine derivative MMV1804559 was able to prolong the survival of M. mycetomatis-infected G. mellonella larvae. Furthermore, the grains in MMV1804559-treated larvae were significantly smaller compared to the PBS-treated group. CONCLUSION: MMV1804559 shows promising in vitro and in vivo activity against M. mycetomatis.

Sandalwood Oils of Different Origins Are Active In Vitro against Madurella mycetomatis, the Major Fungal Pathogen Responsible for Eumycetoma.

In the search for new bioactive agents against the infectious pathogen responsible for the neglected tropical disease (NTD) mycetoma, we tested a collection of 27 essential oils (EOs) in vitro against Madurella mycetomatis, the primary pathogen responsible for the fungal form of mycetoma, termed eumycetoma. Among this series, the EO of Santalum album (Santalaceae), i.e., East Indian sandalwood oil, stood out prominently with the most potent inhibition in vitro. We, therefore, directed our research toward 15 EOs of Santalum species of different geographical origins, along with two samples of EOs from other plant species often commercialized as "sandalwood oils". Most of these EOs displayed similar strong activity against M. mycetomatis in vitro. All tested oils were thoroughly analyzed by GC-QTOF MS and most of their constituents were identified. Separation of the sandalwood oil into the fractions of sesquiterpene hydrocarbons and alcohols showed that its activity is associated with the sesquiterpene alcohols. The major constituents, the sesquiterpene alcohols (Z)-α- and (Z)-ß-santalol were isolated from the S. album oil by column chromatography on AgNO3-coated silica. They were tested as isolated compounds against the fungus, and (Z)-α-santalol was about two times more active than the ß-isomer.

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.

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.

Mycetoma, chromoblastomycosis and other deep fungal infections: diagnostic and treatment approach.

PURPOSE OF REVIEW: to review recent advances in the epidemiology, diagnosis, and treatment of deep fungal infections. RECENT FINDINGS: Mycetoma and chromoblastomycosis are the only deep fungal infections incorporated in the list of neglected tropical diseases. These infections start in the skin but progress to deep tissues if not recognized early. A wide array of fungal pathogens are the causative agents. Molecular methods allow for early and accurate identification of the pathogens, but are unfortunately not available in endemic areas. Treatment options are mostly based upon clinical experience rather than on well-designed clinical trials. SUMMARY: Deep fungal infections of the skin and soft tissues are rare conditions of wide world distribution but mostly reported from tropical countries. Urgent need for affordable and easily accessible molecular methods and well-conducted studies to allow for accurate diagnosis and to provide evidence to guide proper therapy are urgently needed.

Development and validation of a resazurin assay for in vitro susceptibility testing of Actinomadura madurae: a common causative agent of actinomycetoma.

OBJECTIVES: Actinomycetoma is a chronic granulomatous disease affecting skin, subcutaneous tissue, fascia, muscle and bones. With increasing resistance against commonly used treatment regimens, susceptibility testing is urgently needed. METHODS: We developed an in vitro susceptibility assay for Actinomadura madurae, one of the common causative agents of actinomycetoma, employing resazurin for endpoint reading. Using this assay, reproducible MICs were determined for the most commonly used antibacterial agents for actinomycetoma treatment. The tested antibacterial agents included trimethoprim/sulfamethoxazole, amikacin, streptomycin, amoxicillin, ceftriaxone, gentamicin, ciprofloxacin, doxycycline, imipenem, linezolid, penicillin G and rifampicin. RESULTS: Following the clinical breakpoints as stated by CLSI, 100% of the tested strains were susceptible to trimethoprim/sulfamethoxazole (MIC 0.03/0.59-1/19 mg/L), amikacin (MIC 0.0078-0.25 mg/L), doxycycline (MIC <0.25-1 mg/L) and linezolid (MIC <0.25-2 mg/L), 90% to ciprofloxacin (MIC <0.25-2 mg/L), 80% to ceftriaxone (MIC <0.5 to >64 mg/L) and imipenem (MIC <0.25-32 mg/L) and only 20% to amoxicillin (MIC <0.5 to >64 mg/L) and rifampicin (MIC 0.5 to >32 mg/L). CONCLUSIONS: Determinations of MICs by visual readings of colour changes versus spectrophotometric readings were comparable. This convenient visual reading has the advantage of feasible implementation in endemic settings.

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.

Inhibiting DHN- and DOPA-melanin biosynthesis pathway increased the therapeutic value of itraconazole in Madurella mycetomatis infected Galleria mellonella.

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.

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.

Eumycetoma causative agents are inhibited in vitro by luliconazole, lanoconazole and ravuconazole.

INTRODUCTION: Eumycetoma is a subcutaneous mutilating disease that can be caused by many different fungi. Current treatment consists of prolonged itraconazole administration in combination with surgery. In many centres, due to their slow growth rate, the treatment for eumycetoma is often started before the causative agent is identified. This harbours the risk that the causative fungus is not susceptible to the given empirical therapy. In the open-source drug program MycetOS, ravuconazole and luliconazole were promising antifungal agents that were able to inhibit the growth of Madurella mycetomatis, the most common causative agent of mycetoma. However, it is currently not known whether these drugs inhibit the growth of other eumycetoma causative agents. MATERIALS AND METHODS: Here, we determined the in vitro activity of luliconazole, lanoconazole and ravuconazole against commonly encountered eumycetoma causative agents. MICs were determined for lanoconazole, luliconazole and ravuconazole against 37 fungal isolates which included Madurella species, Falciformispora senegalensis, Medicopsis romeroi and Trematosphaeria grisea and compared to those of itraconazole. RESULTS: Ravuconazole, luliconazole and lanoconazole showed high activity against all eumycetoma causative agents tested with median minimal inhibitory concentrations (MICs) ranging from 0.008-2 µg/ml, 0.001-0.064 µg/ml and 0.001-0.064 µg/ml, respectively. Even Ma. fahalii and Me. romeroi, which are not inhibited in growth by itraconazole at a concentration of 4 µg/ml, were inhibited by these azoles. CONCLUSION: The commonly encountered eumycetoma causative agents are inhibited by lanoconazole, luliconazole and ravuconazole. These drugs are promising candidates for further evaluation as potential treatment for eumycetoma.

Eumycetoma Osteomyelitis Calcaneus in Adolescent; report of case and literature review.

BACKGROUND: Mycetoma is the most common neglected disease in humans. It is a chronic, progressive, and destructive disease primarily caused by fungi or bacteria characterized by formation of dark pale grains commonly involve skin, soft tissue and rarely bone. CASE PRESENTATION: A 19 year old male patient with chronic right ankle pain, swelling and abscess formation for more than 1 year, patient was treated repeatedly with incision and drainage without any success. No X-ray, biopsy or swab for culture and sensitivity had been considered through the course of presentation. Patient was referred to Omdurman hospital where osteomyelitis secondary euomycetoma infection has been confirmed based on radiological and pathological assessment. Patient was treated surgically with aggressive debridement and bone curettage plus postoperative Itraconazole for 1 year. CONCLUSION: Clinicians must consider osteomyelitis as important differential diagnosis during initial assessment Eumycetoma infection in adults. Aggressive bone curettage followed by regular X-ray follow up can be limb saving procedure in such cases.

First report of cutaneous mycetoma by Paecilomyces variotii and the successful treatment with combined itraconazole and terbinafine along with resection surgeries.

Mycetoma is a progressively mutilating infectious disease of the subcutaneous tissue that affects the skin and deep structures, which is poorly responsive to chemotherapy. Here, we report a skin mycetoma caused by Paecilomyces variotii, an uncommon fungus of human infections, and the therapeutic approach that resulted in a complete cure of the patient.

Niclosamide Is Active In Vitro against Mycetoma Pathogens.

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 Madurella mycetomatis, 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 M. mycetomatis but also against Actinomadura 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.

[The Importance of Mycological Diagnosis: A Scedosporium apiospermum Complex Mycetoma Case Neglected For 20 Years]. / Mikolojik Taninin Önemi: 20 Yil Ihmal Edilen Bir Scedosporium apiospermum Kompleks Miçetoma Olgusu.

Scedosporium apiospermum complex members are opportunistic fungi that can be found in environments such as soil and polluted water. In this report, we aimed to present a case of mycetoma caused by Scedosporium apiospermum complex that developed in a 40-year-old female patient with immunocompetent system and diagnosed by fungal culture. In the anamnesis of the patient who admitted in 2015 with the complaint of more than one fistulized discharge wound, pain and swelling in the dorsal of the right hand and wrist; it was learned that her complaints started about 20 years ago with a slight swelling on the back of the wrist, and when it worsened, the abscess was drained and antibiotic treatment was initiated in a private surgical center. However, it was learned that she did not benefit from the treatments, and over time, fistulized, yellow-discharged wounds appeared on the back of her hand and wrist, and she had undergone various surgical interventions and used antibiotics. Routine laboratory tests of the patient, who did not have an underlying chronic disease, were normal. Magnetic resonance imaging (MRI) and X-ray findings were compatible with osteomyelitis and 'dot in circle' sign seen on MRI was characteristic for mycetoma. Pathological examination was interpreted as active chronic inflammatory reaction in the soft tissue and chronic osteomyelitis. Mycobacteria, bacteriological and fungal cultures of the two biopsy samples taken during surgical debridement and one month later were performed. Bacteriological and mycobacterial cultures were negative, while Scedosporium genus grew in the fungal cultures of the both samples. Isolates were identified as Scedosporium apiospermum/Pseudallescheria boydii with MALDI Biotyper (Bruker Daltonics, Bremen, Germany) system and Scedosporium boydi by sequence analysis of the ITS region. The antifungal susceptibility tests were performed according to CLSI M38-A2 criteria, and were evaluated at the 72nd hour. The minimum inhibitory concentration (MIC) values of fluconazole, caspofungin, amphotericin B, itraconazole, vorikonazole, posaconazole and isavuconazole were > 64 µg/ml, 16 µg/ml, 4 µg/ml, 16 µg/ml, 0.25 µg/ml, 2 µg/ml and 0.25 µg/ml, respectively. Voriconazole and terbinafine treatment was initiated. In the control performed in the 9th month of the treatment, it was observed that the complaints of discharge, pain and swelling were resolved, pain and swelling complaints were recovered, fistula tracts were closed and joint movements were painless. In the control MRI performed at 15th and 18th months, it was observed that there was no soft tissue involvement and the findings were compatible with osteoarthritis after infective osteomyelitis. This case whose longterm complaints improved with mycological diagnosis and appropriate treatment; reveals the importance of keeping mycological diagnosis in mind in chronic bone and soft tissue infections. Identifying the fungus to the genus and species level and arranging the treatment according to the antifungal susceptibility test results are very important in patient management.

Madurella mycetomatis, the main causative agent of eumycetoma, is highly susceptible to olorofim.

OBJECTIVES: Eumycetoma is currently treated with a combination of itraconazole therapy and surgery, with limited success. Recently, olorofim, the lead candidate of the orotomides, a novel class of antifungal agents, entered a Phase II trial for the treatment of invasive fungal infections. Here we determined the activity of olorofim against Madurella mycetomatis, the main causative agent of eumycetoma. METHODS: Activity of olorofim against M. mycetomatis was determined by in silico comparison of the target gene, dihydroorotate dehydrogenase (DHODH), and in vitro susceptibility testing. We also investigated the in vitro interaction between olorofim and itraconazole against M. mycetomatis. RESULTS: M. mycetomatis and Aspergillus fumigatus share six out of seven predicted binding residues in their DHODH DNA sequence, predicting susceptibility to olorofim. Olorofim demonstrated excellent potency against M. mycetomatis in vivo with MICs ranging from 0.004 to 0.125 mg/L and an MIC90 of 0.063 mg/L. Olorofim MICs were mostly one dilution step lower than the itraconazole MICs. In vitro interaction studies demonstrated that olorofim and itraconazole work indifferently when combined. CONCLUSIONS: We demonstrated olorofim has potent in vitro activity against M. mycetomatis and should be further evaluated in vivo as a treatment option for this disease.