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Nyuykonge B, Siddig EE, Nyaoke BA, Zijlstra EE, Verbon A, Bakhiet SM, Fahal AH, van de Sande WWJ. Using (1,3)-β-D-glucan concentrations in serum to monitor the response of azole therapy in patients with eumycetoma caused by Madurella mycetomatis. Mycoses 2024; 67:e13664. [PMID: 37872649 DOI: 10.1111/myc.13664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 10/03/2023] [Accepted: 10/08/2023] [Indexed: 10/25/2023]
Abstract
INTRODUCTION (1,3)-β-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)-β-D-glucan was present in serum of patients with eumycetoma. However, the use of (1,3)-β-D-glucan to monitor treatment responses in patients with eumycetoma has not been evaluated. MATERIALS AND METHODS In this study, we measured (1,3)-β-D-glucan concentrations in serum with the WAKO (1,3)-β-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)-β-D-glucan concentrations were measured at seven different timepoints. Any correlation between initial and final (1,3)-β-D-glucan concentrations and clinical outcome was evaluated. RESULTS The concentration of (1,3)-β-D-glucan was obtained in a total of 654 serum samples. Before treatment, the average (1,3)-β-D-glucan concentration was 22.86 pg/mL. During the first 6 months of treatment, this concentration remained stable. (1,3)-β-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)-β-D-glucan concentration above the 5.5 pg/mL cut-off value for positivity, while in the remaining 11 patients, (1,3)-β-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)-β-D-glucan concentration was noted. CONCLUSION Although in general (1,3)-β-D-glucan concentrations can be measured in the serum of patients with eumycetoma during treatment, a sharp decrease in β-glucan concentration was only noted after surgery and not during or after antimicrobial treatment. (1,3)-β-D-glucan concentrations were not predictive for recurrence and seem to have no value in determining treatment response to azoles in patients with eumycetoma.
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Affiliation(s)
- Bertrand Nyuykonge
- Department of Medical Microbiology and Infectious Diseases, Erasmus MC, University Medical Centre Rotterdam, Rotterdam, Netherlands
| | | | - Borna A Nyaoke
- Drugs for Neglected Diseases initiative (DNDi), Geneva, Switzerland
| | | | - Annelies Verbon
- Department of Medical Microbiology and Infectious Diseases, Erasmus MC, University Medical Centre Rotterdam, Rotterdam, Netherlands
| | - Sahar M Bakhiet
- Mycetoma Research Centre, University of Khartoum, Khartoum, Sudan
| | - Ahmed H Fahal
- Mycetoma Research Centre, University of Khartoum, Khartoum, Sudan
| | - Wendy W J van de Sande
- Department of Medical Microbiology and Infectious Diseases, Erasmus MC, University Medical Centre Rotterdam, Rotterdam, Netherlands
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Konings M, Eadie K, Strepis N, Nyuykonge B, Fahal AH, Verbon A, van de Sande WWJ. The combination of manogepix and itraconazole is synergistic and inhibits the growth of Madurella mycetomatis in vitro but not in vivo. Med Mycol 2023; 61:myad118. [PMID: 37960934 PMCID: PMC10684268 DOI: 10.1093/mmy/myad118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 10/17/2023] [Accepted: 11/10/2023] [Indexed: 11/15/2023] Open
Abstract
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.
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Affiliation(s)
- Mickey Konings
- Department of Medical Microbiology and Infectious Diseases, ErasmusMC University Medical Center Rotterdam, Dr. Molewaterplein 40, 3015GD, Rotterdam, The Netherlands
| | - Kimberly Eadie
- Department of Medical Microbiology and Infectious Diseases, ErasmusMC University Medical Center Rotterdam, Dr. Molewaterplein 40, 3015GD, Rotterdam, The Netherlands
| | - Nikolaos Strepis
- Department of Medical Microbiology and Infectious Diseases, ErasmusMC University Medical Center Rotterdam, Dr. Molewaterplein 40, 3015GD, Rotterdam, The Netherlands
| | - Bertrand Nyuykonge
- Department of Medical Microbiology and Infectious Diseases, ErasmusMC University Medical Center Rotterdam, Dr. Molewaterplein 40, 3015GD, Rotterdam, The Netherlands
| | - Ahmed H Fahal
- Mycetoma Research Center, University of Khartoum, Khartoum, Sudan
| | - Annelies Verbon
- Department of Medical Microbiology and Infectious Diseases, ErasmusMC University Medical Center Rotterdam, Dr. Molewaterplein 40, 3015GD, Rotterdam, The Netherlands
- Department of Internal Medicine, UMC Utrecht, Utrecht, The Netherlands
| | - Wendy W J van de Sande
- Department of Medical Microbiology and Infectious Diseases, ErasmusMC University Medical Center Rotterdam, Dr. Molewaterplein 40, 3015GD, Rotterdam, The Netherlands
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Nyuykonge B, Siddig E, Mhmoud NA, Bakhiet S, Zijlstra E, Verbon A, Fahal AH, van de Sande WWJ. Wako β-D-glucan assay can be used to measure serum β-D-glucan in Sudanese patients to aid with diagnosis of eumycetoma caused by Madurella mycetomatis. J Eur Acad Dermatol Venereol 2023; 37:783-786. [PMID: 36201367 DOI: 10.1111/jdv.18642] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Accepted: 09/14/2022] [Indexed: 11/27/2022]
Abstract
BACKGROUND Eumycetoma is a neglected tropical infection of the subcutaneous tissue commonly caused by the fungus Madurella mycetomatis. Previously, we demonstrated that β-D-glucan was present in the serum of eumycetoma patients. OBJECTIVE To compare the performance of the recently approved easy-to-use Wako β-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 β-glucan serum concentrations using the Wako assay and compared the performance to that of the Fungitell assay. RESULTS With the Fungitell assay, median β-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 β-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.
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Affiliation(s)
- Bertrand Nyuykonge
- Department of Medical Microbiology and Infectious Diseases, Erasmus MC University Medical Centre Rotterdam, Rotterdam, The Netherlands
| | - Emmanuel Siddig
- Department of Medical Microbiology and Infectious Diseases, Erasmus MC University Medical Centre Rotterdam, Rotterdam, The Netherlands.,Mycetoma Research Centre, University of Khartoum, Khartoum, Sudan
| | - Najwa A Mhmoud
- Mycetoma Research Centre, University of Khartoum, Khartoum, Sudan
| | - Sahar Bakhiet
- Mycetoma Research Centre, University of Khartoum, Khartoum, Sudan
| | - Eduard Zijlstra
- Drugs for Neglected Diseases Initiative (DNDi), Geneva, Switzerland
| | - Annelies Verbon
- Department of Medical Microbiology and Infectious Diseases, Erasmus MC University Medical Centre Rotterdam, Rotterdam, The Netherlands
| | - Ahmed H Fahal
- Mycetoma Research Centre, University of Khartoum, Khartoum, Sudan
| | - Wendy W J van de Sande
- Department of Medical Microbiology and Infectious Diseases, Erasmus MC University Medical Centre Rotterdam, Rotterdam, The Netherlands
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Siddig EE, Nyuykonge B, Mhmoud NA, Abdallah OB, Bahar MEN, Ahmed ES, Nyaoke B, Zijlstra EE, Verbon A, Bakhiet SM, Fahal AH, van de Sande WWJ. Comparing the performance of the common used eumycetoma diagnostic tests. Mycoses 2022; 66:420-429. [PMID: 36583225 DOI: 10.1111/myc.13561] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 12/15/2022] [Accepted: 12/20/2022] [Indexed: 12/31/2022]
Abstract
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.
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Affiliation(s)
- Emmanuel Edwar Siddig
- Department of Medical Microbiology and Infectious Diseases, Erasmus MC, University Medical Centre Rotterdam, Rotterdam, the Netherlands.,Mycetoma Research Centre, University of Khartoum, Khartoum, Sudan.,Faculty of Medical Laboratory Sciences, University of Khartoum, Khartoum, Sudan
| | - Bertrand Nyuykonge
- Department of Medical Microbiology and Infectious Diseases, Erasmus MC, University Medical Centre Rotterdam, Rotterdam, the Netherlands
| | - Najwa Adam Mhmoud
- Mycetoma Research Centre, University of Khartoum, Khartoum, Sudan.,Faculty of Medical Laboratory Sciences, University of Khartoum, Khartoum, Sudan
| | | | | | | | - Borna Nyaoke
- Drugs for Neglected Diseases initiative, DNDi, Nairobi, Kenya
| | | | - Annelies Verbon
- Department of Medical Microbiology and Infectious Diseases, Erasmus MC, University Medical Centre Rotterdam, Rotterdam, the Netherlands
| | | | | | - Wendy W J van de Sande
- Department of Medical Microbiology and Infectious Diseases, Erasmus MC, University Medical Centre Rotterdam, Rotterdam, the Netherlands
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Nyuykonge B, Siddig EE, Mhmoud NA, Nyaoke BA, Zijlstra EE, Verbon A, Bakhiet S, Fahal AH, van de Sande WWJ. Epidemiological cut-off values for itraconazole and ravuconazole for Madurella mycetomatis, the most common causative agent of mycetoma. Mycoses 2022; 65:1170-1178. [PMID: 36005544 PMCID: PMC9804462 DOI: 10.1111/myc.13509] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 07/16/2022] [Accepted: 07/26/2022] [Indexed: 01/05/2023]
Abstract
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.
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Affiliation(s)
- Bertrand Nyuykonge
- Department of Medical Microbiology and Infectious DiseasesErasmus MC, University Medical Centre RotterdamRotterdamthe Netherlands
| | | | | | | | | | - Annelies Verbon
- Department of Medical Microbiology and Infectious DiseasesErasmus MC, University Medical Centre RotterdamRotterdamthe Netherlands
| | - Sahar Bakhiet
- Mycetoma Research CentreUniversity of KhartoumKhartoumSudan
| | - Ahmed H. Fahal
- Mycetoma Research CentreUniversity of KhartoumKhartoumSudan
| | - Wendy W. J. van de Sande
- Department of Medical Microbiology and Infectious DiseasesErasmus MC, University Medical Centre RotterdamRotterdamthe Netherlands
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Siddig EE, Nyuykonge B, Bakheit OELH, Hassan OB, Ahmed ES, Osman AA, Bakhiet SM, van de Sande WWJ, Fahal AH. Staphylococcus aureus causing primary foot botryomycosis mimicking actinomycetoma: a case report from Sudan. Int J Infect Dis 2022; 124:224-226. [DOI: 10.1016/j.ijid.2022.10.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Revised: 10/03/2022] [Accepted: 10/06/2022] [Indexed: 11/15/2022] Open
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Nyuykonge B, Siddig E, Mhmoud N, Nyaoke B, Zijlstra E, Verbon A, Bakhiet S, Fahal A, Van de Sande W. S4.5c Using serum beta-glucan measurements and sequencing of the Madurella mycetomatis azole target gene to predict therapeutic outcome during azole treatment in human mycetoma. Med Mycol 2022. [PMCID: PMC9516349 DOI: 10.1093/mmy/myac072.s4.5c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
S4.5 Mycetoma Clinical Trial on fosravuconazole treatment in eumycetoma– Top Line Results, September 22, 2022, 10:30 AM - 12:00 PM
Objectives
Eumycetoma is a neglected tropical disease characterized by large subcutaneous swellings and the formation of grains and most commonly caused by Madurella mycetomatis. The currently recommended therapy is a combination of antifungal therapy with an azole and surgery. Itraconazole is the current recommended drug and fosravuconazole, the pro-drug of ravuconzole, is currently clinically investigated. At the moment, there are no epidemiological cut-off values (ECV) for M. mycetomatis for either of these drugs or rapid diagnostic tests which can predict the therapeutic outcome of these treatments. Therefore, in this study, we determined the ECV for these drugs and determined whether there was a correlation between minimal inhibitory concentration (MIC) and the DNA sequence of the azole target gene CYP51A. We also assessed beta-glucan concentrations in the serum of mycetoma patients during treatment to establish whether any of these values were predictive for therapeutic outcomes.
Methods
In order to determine the ECV for M. mycetomatis, MIC distributions for itraconazole and ravuconazole were determined in genetically diverse clinical M. mycetomatis isolates using the ECOFFinder software. CYP51A sequences were sequenced and comparisons were made between the different CYP51A variants and the MIC distributions. Beta-glucan concentrations were measured in serum with the WAKO beta-glucan assay. Time points analyzed were 0, 22, 85, 176, 267, 358, and 455 days after the start of treatment.
Results
For M. mycetomatis 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. The MIC distributions for itraconazole and ravuconazole were similar between the two variants. No mutations linked to decreased susceptibility were found. Before the start of treatment, beta-glucan concentrations ranged from below the detection limit to 217.9 pg/ml. Of these patients, 61.2% had a beta-glucan concentration above 7 pg/ml, the recommended cut-off value for positivity by the manufacturer, 72.8% had a beta-glucan concentration above 5.5 pg/ml, the recommended cut-off value for M. mycetomatis. During the first months of azole treatment, the beta-glucan concentrations remained relatively stable. After surgery, a sharp decrease in beta-glucan concentration in serum was noted. At the end of the observation period, only 13 patients had a beta-glucan concentration above 7 pg/ml and 14 above 5.5 pg/ml. Of these patients, for only 3, there was clinical evidence of a recurrence. For the remaining 4 patients with clinical evidence of a recurrence, the beta-glucan concentration was below the cut-off value for positivity.
Conclusion
In conclusion, so far there was no link established with the initial in vitro susceptibility and failure or success of the treatment therapy. Beta-glucan levels, in general, remained high during azole treatment, and a sharp drop in beta-glucan concentration in serum was only noted after surgery. A positive beta-glucan concentration at the end of the treatment was not indicative of a recurrence.
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Affiliation(s)
- Bertrand Nyuykonge
- ErasmusMC - Erasmus University Hospital - Department of Medical Microbiology & Infectious Diseases , Rotterdam , Netherlands
| | - Emmanuel Siddig
- ErasmusMC - Erasmus University Hospital - Department of Medical Microbiology & Infectious Diseases , Rotterdam , Netherlands
- Mycetoma Research Centre , University of Khartoum, Khartoum , Sudan
- University of Khartoum , Faculty of medical laboratory sciences, Khartoum , Sudan
| | - Najwa Mhmoud
- Mycetoma Research Centre , University of Khartoum, Khartoum , Sudan
| | - Borna Nyaoke
- Drugs for Neglected Diseases initiative (DNDi) , Geneva , Switzerland
| | - Ed Zijlstra
- Drugs for Neglected Diseases initiative (DNDi) , Geneva , Switzerland
| | - Annelies Verbon
- ErasmusMC - Erasmus University Hospital - Department of Medical Microbiology & Infectious Diseases , Rotterdam , Netherlands
| | - Sahar Bakhiet
- Mycetoma Research Centre , University of Khartoum, Khartoum , Sudan
| | - Ahmed Fahal
- Mycetoma Research Centre , University of Khartoum, Khartoum , Sudan
| | - Wendy Van de Sande
- ErasmusMC - Erasmus University Hospital - Department of Medical Microbiology & Infectious Diseases , Rotterdam , Netherlands
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Siddig E, Nyuykonge B, Mhmoud N, Abdallah O, Bahar M, Ahmed E, Nyaoke B, Zijlstra E, Verbon A, Bakhiet S, Fahal A, van de Sande W. S4.5d Comparing the diagnostic performance of the commonly used eumycetoma diagnostic tests using sequencing of the internally transcribed spacer region as the gold standard. Med Mycol 2022. [PMCID: PMC9516265 DOI: 10.1093/mmy/myac072.s4.5d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
S4.5 Mycetoma Clinical Trial on fosravuconazole treatment in eumycetoma– Top Line Results, September 22, 2022, 10:30 AM - 12:00 PM 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 In total 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. A total of 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 h 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.
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Affiliation(s)
- Emmanuel Siddig
- Erasmus MC , University Medical Centre Rotterdam, Department of Medical Microbiology and Infectious Diseases, Rotterdam, Netherlands, Rotterdam , Netherlands
- Mycetoma Research Centre , University of Khartoum, Khartoum, Sudan, Sudan , Sudan
- University of Khartoum , Faculty of medical laboratory sciences, Khartoum, Sudan, Khartoum , Sudan
| | - Bertrand Nyuykonge
- Erasmus MC , University Medical Centre Rotterdam, Department of Medical Microbiology and Infectious Diseases, Rotterdam, Netherlands, Rotterdam , Netherlands
| | - Najwa Mhmoud
- Mycetoma Research Centre , University of Khartoum, Khartoum, Sudan, Sudan , Sudan
- University of Khartoum , Faculty of medical laboratory sciences, Khartoum, Sudan, Khartoum , Sudan
| | - Omnia Abdallah
- Mycetoma Research Centre , University of Khartoum, Khartoum, Sudan, Sudan , Sudan
| | - Mustafa Bahar
- Mycetoma Research Centre , University of Khartoum, Khartoum, Sudan, Sudan , Sudan
| | - Eiman Ahmed
- Mycetoma Research Centre , University of Khartoum, Khartoum, Sudan, Sudan , Sudan
| | - Borna Nyaoke
- Drugs for Neglected Diseases initiative (DNDi) , Switzerland , Switzerland
| | - Ed Zijlstra
- Drugs for Neglected Diseases initiative (DNDi) , Switzerland , Switzerland
| | - Annelies Verbon
- Erasmus MC , University Medical Centre Rotterdam, Department of Medical Microbiology and Infectious Diseases, Rotterdam, Netherlands, Rotterdam , Netherlands
| | - Sahar Bakhiet
- Mycetoma Research Centre , University of Khartoum, Khartoum, Sudan, Sudan , Sudan
| | - Ahmed Fahal
- Mycetoma Research Centre , University of Khartoum, Khartoum, Sudan, Sudan , Sudan
| | - Wendy van de Sande
- Erasmus MC , University Medical Centre Rotterdam, Department of Medical Microbiology and Infectious Diseases, Rotterdam, Netherlands, Rotterdam , Netherlands
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Siddig E, Nyuykonge B, Mhmoud N, Abdallah O, Bahar M, Ahmed E, Nyaoke B, Zijlstra E, Verbon A, Bakhiet S, Fahal A, van de Sande W. P445 Clinical evaluation of the performance of the most commonly used eumycetoma diagnostic tests using sequencing of the internally transcribed spacer region as the golden standard. Med Mycol 2022. [PMCID: PMC9515937 DOI: 10.1093/mmy/myac072.p445] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Poster session 3, September 23, 2022, 12:30 PM - 1:30 PM Objective Mycetoma is a neglected tropical skin disease, caused by 70 different causative agents. For most of the causative agents, molecular identification is the only reliable method to identify the species level. In practice, ultrasound, histopathology, culturing, and species-specific PCRs are most commonly used for species identification. However, the performance of these different tests was not validated using molecular identification by sequencing barcoding genes. Methods In this study, we validated the performance of the most commonly used diagnostic tools including culture, histopathology, Ultrasound and two species-specific PCR for Madurella mycetomatis on 222 patients suspected of fungal mycetoma by M. mycetomatis; the sensitivity, specificity, and accuracy of each method was calculated. Results From the 222 patients, 154 (69.3%) were correctly identified by ultrasound, histology, culture, and both species-specific PCRs. For five patients all tests were negative and for three only the ultrasound was indicative of mycetoma. For the other 60 patients, at least one of the assays was negative for M. mycetomatis. The two species-specific PCRs were the most sensitive and specific, followed by culture and histology. Ultrasound was the least specific as it only allows to differentiate between actinomycetoma and eumycetoma. However, with ultrasound, an identification could be obtained in 9.38 min. PCR took 3.76 h, histology 8.5 days, and culturing 21 days. Conclusion We concluded that PCR directly on DNA isolated from grains is the most rapid and reliable diagnostic tool to identify M. mycetomatis from eumycetoma grains to use species-specific PCRs. In order to shorten the time to identification of other causative agents, the focus should be on developing more molecular assays for those species.
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Affiliation(s)
| | - Bertrand Nyuykonge
- Erasmus MC , University Medical Centre Rotterdam, Department of Medical Microbiology and Infectious Diseases, Rotterdam, Netherlands., Rotterdam , The Netherland
| | | | | | | | | | - Borna Nyaoke
- Drugs for Neglected Tropical Disease Initiative , Switzerland
| | - Eduard Zijlstra
- Drugs for Neglected Tropical Disease Initiative , Switzerland
| | - Annelies Verbon
- Erasmus MC , University Medical Centre Rotterdam, Department of Medical Microbiology and Infectious Diseases, Rotterdam, Netherlands., Rotterdam , The Netherland
| | | | | | - Wendy van de Sande
- Erasmus MC , University Medical Centre Rotterdam, Department of Medical Microbiology and Infectious Diseases, Rotterdam, Netherlands., Rotterdam , The Netherland
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10
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Nyuykonge B, Siddig EE, Konings M, Bakhiet S, Verbon A, Klaassen CHW, Fahal AH, van de Sande WWJ. Madurella mycetomatis grains within a eumycetoma lesion are clonal. Med Mycol 2022; 60:6643561. [PMID: 35833294 PMCID: PMC9335062 DOI: 10.1093/mmy/myac051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Revised: 06/16/2022] [Accepted: 07/12/2022] [Indexed: 11/23/2022] Open
Abstract
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.
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Affiliation(s)
- Bertrand Nyuykonge
- Department of Medical Microbiology and Infectious Diseases, Erasmus MC, University Medical Centre Rotterdam, Rotterdam, Netherlands
| | - Emmanuel Edwar Siddig
- Mycetoma Research Centre, University of Khartoum, Khartoum, Sudan.,Faculty of medical laboratory sciences, University of Khartoum, Khartoum, Sudan
| | - Mickey Konings
- Department of Medical Microbiology and Infectious Diseases, Erasmus MC, University Medical Centre Rotterdam, Rotterdam, Netherlands
| | - Sahar Bakhiet
- Mycetoma Research Centre, University of Khartoum, Khartoum, Sudan
| | - Annelies Verbon
- Department of Medical Microbiology and Infectious Diseases, Erasmus MC, University Medical Centre Rotterdam, Rotterdam, Netherlands
| | - Corné H W Klaassen
- Department of Medical Microbiology and Infectious Diseases, Erasmus MC, University Medical Centre Rotterdam, Rotterdam, Netherlands
| | | | - Wendy W J van de Sande
- Department of Medical Microbiology and Infectious Diseases, Erasmus MC, University Medical Centre Rotterdam, Rotterdam, Netherlands
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11
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Nyuykonge B, Lim W, van Amelsvoort L, Bonifaz A, Fahal A, Badali H, Abbastabar M, Verbon A, van de Sande W. Eumycetoma Causative Agents are Inhibited
in vitro
by Luliconazole, Lanoconazole and Ravuconazole. Mycoses 2022; 65:650-655. [PMID: 35398930 PMCID: PMC9321754 DOI: 10.1111/myc.13442] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Revised: 03/30/2022] [Accepted: 04/04/2022] [Indexed: 11/29/2022]
Abstract
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.
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Affiliation(s)
- Bertrand Nyuykonge
- Erasmus MC University Medical Center Rotterdam Department of Medical Microbiology and Infectious Diseases Dr Molewaterplein 40 3015 GD Rotterdam The Netherlands
| | - Wilson Lim
- Erasmus MC University Medical Center Rotterdam Department of Medical Microbiology and Infectious Diseases Dr Molewaterplein 40 3015 GD Rotterdam The Netherlands
| | - Lukas van Amelsvoort
- Erasmus MC University Medical Center Rotterdam Department of Medical Microbiology and Infectious Diseases Dr Molewaterplein 40 3015 GD Rotterdam The Netherlands
| | | | | | - Hamid Badali
- Invasive Fungi Research Center (IFRC) Communicable Diseases Institute Mazandaran University of Medical Sciences Sari Iran
| | - Mahdi Abbastabar
- Invasive Fungi Research Center (IFRC) Communicable Diseases Institute Mazandaran University of Medical Sciences Sari Iran
| | - Annelies Verbon
- Erasmus MC University Medical Center Rotterdam Department of Medical Microbiology and Infectious Diseases Dr Molewaterplein 40 3015 GD Rotterdam The Netherlands
| | - Wendy van de Sande
- Erasmus MC University Medical Center Rotterdam Department of Medical Microbiology and Infectious Diseases Dr Molewaterplein 40 3015 GD Rotterdam The Netherlands
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12
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Lim W, Nyuykonge B, Eadie K, Konings M, Smeets J, Fahal A, Bonifaz A, Todd M, Perry B, Samby K, Burrows J, Verbon A, van de Sande W. Screening the pandemic response box identified benzimidazole carbamates, Olorofim and ravuconazole as promising drug candidates for the treatment of eumycetoma. PLoS Negl Trop Dis 2022; 16:e0010159. [PMID: 35120131 PMCID: PMC8815882 DOI: 10.1371/journal.pntd.0010159] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Accepted: 01/10/2022] [Indexed: 12/18/2022] Open
Abstract
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.
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Affiliation(s)
- Wilson Lim
- Erasmus MC, University Medical Center Rotterdam, Department of Microbiology and Infectious Diseases, Rotterdam, The Netherlands
| | - Bertrand Nyuykonge
- Erasmus MC, University Medical Center Rotterdam, Department of Microbiology and Infectious Diseases, Rotterdam, The Netherlands
| | - Kimberly Eadie
- Erasmus MC, University Medical Center Rotterdam, Department of Microbiology and Infectious Diseases, Rotterdam, The Netherlands
| | - Mickey Konings
- Erasmus MC, University Medical Center Rotterdam, Department of Microbiology and Infectious Diseases, Rotterdam, The Netherlands
| | - Juli Smeets
- Erasmus MC, University Medical Center Rotterdam, Department of Microbiology and Infectious Diseases, Rotterdam, The Netherlands
| | - Ahmed Fahal
- Mycetoma Research Centre, University of Khartoum, Khartoum, Sudan
| | | | - Matthew Todd
- University College London, School of Pharmacy, London, United Kingdom
| | - Benjamin Perry
- Drugs for Neglected Diseases initiative (DNDi), Geneva, Switzerland
| | | | - Jeremy Burrows
- Medicines for Malaria Venture (MMV), Geneva, Switzerland
| | - Annelies Verbon
- Erasmus MC, University Medical Center Rotterdam, Department of Microbiology and Infectious Diseases, Rotterdam, The Netherlands
| | - Wendy van de Sande
- Erasmus MC, University Medical Center Rotterdam, Department of Microbiology and Infectious Diseases, Rotterdam, The Netherlands
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13
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Siddig EE, Nyuykonge B, Ahmed MT, Hassan R, Saad ESA, Mhmoud NA, Bakhiet SM, van de Sande WWJ, Fahal AH. Human actinomycetoma caused by Actinomadura mexicana in Sudan: the first report. Trans R Soc Trop Med Hyg 2021; 115:406-410. [PMID: 33382899 DOI: 10.1093/trstmh/traa145] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Revised: 10/09/2020] [Accepted: 11/08/2020] [Indexed: 11/14/2022] Open
Abstract
Mycetoma is a localized, chronic, granulomatous disease that can be caused by fungi (eumycetoma) or bacteria (actinomycetoma). Of the 70 different causative agents implicated in mycetoma worldwide, Actinomadura madurae is the only one that causes multiple cases on all continents. Recently, new Actinomadura species were described as causative agents of human mycetoma. One of these new causative agents was Actinomadura mexicana, which was identified in Latin America. Here we demonstrate that this causative agent is not confined to Latin America and that it is also a causative agent of actinomycetoma in Sudan. The disease was managed by antibiotic treatment alone and resulted in complete cure after 6 months of treatment, which is quick when compared with actinomycetoma cases caused by other Actinomadura species.
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Affiliation(s)
- Emmanuel Edwar Siddig
- Mycetoma Research Centre, University of Khartoum, P.O. Box 102, Khartoum, Sudan.,Department of Medical Microbiology and Infectious Diseases, Erasmus University Medical Centre, Rotterdam, The Netherlands
| | - Bertrand Nyuykonge
- Department of Medical Microbiology and Infectious Diseases, Erasmus University Medical Centre, Rotterdam, The Netherlands
| | | | - Rowa Hassan
- Mycetoma Research Centre, University of Khartoum, P.O. Box 102, Khartoum, Sudan.,Brighton and Sussex Centre for Global Health Research, Brighton and Sussex Medical School, Brighton, UK
| | | | - Najwa Adam Mhmoud
- Mycetoma Research Centre, University of Khartoum, P.O. Box 102, Khartoum, Sudan
| | - Sahar Mubarak Bakhiet
- Mycetoma Research Centre, University of Khartoum, P.O. Box 102, Khartoum, Sudan.,Institute of Endemic Diseases, University of Khartoum, Khartoum, Sudan
| | - Wendy W J van de Sande
- Department of Medical Microbiology and Infectious Diseases, Erasmus University Medical Centre, Rotterdam, The Netherlands
| | - Ahmed Hassan Fahal
- Mycetoma Research Centre, University of Khartoum, P.O. Box 102, Khartoum, Sudan
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14
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Mhmoud NA, Siddig EE, Nyuykonge B, Bakhiet SM, van de Sande WWJ, Fahal AH. Mycetoma caused by Microascus gracilis: a novel agent of human eumycetoma in Sudan. Trans R Soc Trop Med Hyg 2021; 115:426-430. [PMID: 33515449 DOI: 10.1093/trstmh/trab010] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Revised: 12/06/2020] [Accepted: 01/08/2021] [Indexed: 11/13/2022] Open
Abstract
Species of the genus Microascus are uncommon agents of human diseases despite their ubiquitous presence in the environment. In this communication, the first case of white grain eumycetoma caused by the fungus Microascus gracilis is reported. The patient was initially misdiagnosed as having actinomycetoma based on the grains morphological and cytological features and was treated with antimicrobial therapy with no clinical improvement. She underwent wide local surgical excision to improve the response to medical treatment and further grain cultural, molecular and taxonomy techniques were conducted and the diagnosis of mycetoma due to M. gracilis was established. The antifungal susceptibilities of this isolate to nine drugs were tested in vitro and they showed poor activity. Combination therapy with surgery and itraconazole led to complete recovery. A medical literature search revealed no previous report on M. gracilis as a causative agent of eumycetoma and hence we are reporting this new causative agent of human eumycetoma. Also, the difficulty in the management of this patient emphasizes the need for accurate and appropriate diagnostic tests for the identification of mycetoma-causative organisms and thus proper management.
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Affiliation(s)
- Najwa A Mhmoud
- Mycetoma Research Centre, University of Khartoum, PO Box 102, Khartoum, Sudan.,Faculty of Medical Laboratory Sciences, University of Khartoum, Khartoum, Sudan
| | - Emmanuel Edwar Siddig
- Mycetoma Research Centre, University of Khartoum, PO Box 102, Khartoum, Sudan.,Faculty of Medical Laboratory Sciences, University of Khartoum, Khartoum, Sudan.,Erasmus MC, University Medical Centre Rotterdam, Department of Medical Microbiology and Infectious Diseases, Rotterdam, The Netherlands
| | - Bertrand Nyuykonge
- Erasmus MC, University Medical Centre Rotterdam, Department of Medical Microbiology and Infectious Diseases, Rotterdam, The Netherlands
| | - Sahar Mubarak Bakhiet
- Mycetoma Research Centre, University of Khartoum, PO Box 102, Khartoum, Sudan.,Institute of Endemic Diseases, University of Khartoum, Khartoum, Sudan
| | - Wendy W J van de Sande
- Erasmus MC, University Medical Centre Rotterdam, Department of Medical Microbiology and Infectious Diseases, Rotterdam, The Netherlands
| | - Ahmed Hassan Fahal
- Mycetoma Research Centre, University of Khartoum, PO Box 102, Khartoum, Sudan
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15
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Lim W, Siddig E, Eadie K, Nyuykonge B, Ahmed S, Fahal A, Verbon A, Smit S, van de Sande WWJ. The development of a novel diagnostic PCR for Madurella mycetomatis using a comparative genome approach. PLoS Negl Trop Dis 2020; 14:e0008897. [PMID: 33326425 PMCID: PMC7743967 DOI: 10.1371/journal.pntd.0008897] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Accepted: 10/17/2020] [Indexed: 12/17/2022] Open
Abstract
Background Eumycetoma is a neglected tropical disease most commonly caused by the fungus Madurella mycetomatis. Identification of eumycetoma causative agents can only be reliably performed by molecular identification, most commonly by species-specific PCR. The current M. mycetomatis specific PCR primers were recently discovered to cross-react with Madurella pseudomycetomatis. Here, we used a comparative genome approach to develop a new M. mycetomatis specific PCR for species identification. Methodology Predicted-protein coding sequences unique to M. mycetomatis were first identified in BLASTCLUST based on E-value, size and presence of orthologues. Primers were then developed for 16 unique sequences and evaluated against 60 M. mycetomatis isolates and other eumycetoma causing agents including the Madurella sibling species. Out of the 16, only one was found to be specific to M. mycetomatis. Conclusion We have discovered a predicted-protein coding sequence unique to M. mycetomatis and have developed a new species-specific PCR to be used as a novel diagnostic marker for M. mycetomatis. Mycetoma is a neglected tropical disease characterised by tumorous swellings and grain formation. This disease can be caused by more than 70 different micro-organisms and is categorised into actinomycetoma (caused by bacteria) and eumycetoma (caused by fungi). The most common causative agent of mycetoma is the fungus Madurella mycetomatis. Diagnosis of eumycetoma is often only done clinically or by histopathological examination and culturing of the grains. Unfortunately, that often leads to misidentifications. Molecular identification is currently the most reliable method to identify the causative agents. However, we have recently discovered that the only M. mycetomatis species-specific PCR primers cross-reacts to Madurella pseudomycetomatis. Since all Madurella species cause eumycetoma and have different susceptibilities to antifungal agents, it is important to be able to accurately identify them to the species level. Here we have used a comparative genome approach to identify and design new M. mycetomatis species-specific PCR primers. These primers can be used to identify M. mycetomatis directly from grains and do not cross-react with any of the other eumycetoma causative agents tested. We, therefore, recommended the use of these primers in reference centres and local laboratories to identify M. mycetomatis to the species level.
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Affiliation(s)
- Wilson Lim
- Erasmus MC, University Medical Center Rotterdam, Department of Microbiology and Infectious Diseases, Rotterdam, The Netherlands
| | - Emmanuel Siddig
- Erasmus MC, University Medical Center Rotterdam, Department of Microbiology and Infectious Diseases, Rotterdam, The Netherlands
- Mycetoma Research Centre, University of Khartoum, Khartoum, Sudan
| | - Kimberly Eadie
- Erasmus MC, University Medical Center Rotterdam, Department of Microbiology and Infectious Diseases, Rotterdam, The Netherlands
| | - Bertrand Nyuykonge
- Erasmus MC, University Medical Center Rotterdam, Department of Microbiology and Infectious Diseases, Rotterdam, The Netherlands
| | - Sarah Ahmed
- Westerdijk Fungal Biodiversity Institute, Utrecht, The Netherlands
| | - Ahmed Fahal
- Mycetoma Research Centre, University of Khartoum, Khartoum, Sudan
| | - Annelies Verbon
- Erasmus MC, University Medical Center Rotterdam, Department of Microbiology and Infectious Diseases, Rotterdam, The Netherlands
| | - Sandra Smit
- Wageningen University & Research, Department of Plant Science, Wageningen, The Netherlands
| | - Wendy WJ van de Sande
- Erasmus MC, University Medical Center Rotterdam, Department of Microbiology and Infectious Diseases, Rotterdam, The Netherlands
- * E-mail:
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16
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Nyuykonge B, Klaassen CHW, Zandijk WHA, de Hoog GS, Ahmed SA, Desnos-Ollivier M, Verbon A, Bonifaz A, van de Sande WWJ. Diagnostic implications of mycetoma derived from Madurella pseudomycetomatis isolates from Mexico. J Eur Acad Dermatol Venereol 2020; 34:1828-1834. [PMID: 32233084 PMCID: PMC7497165 DOI: 10.1111/jdv.16402] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Accepted: 03/10/2020] [Indexed: 01/21/2023]
Abstract
Background At the dermatology service of the General Hospital of Mexico City, Mexico, two patients, father and son, with black‐grain mycetoma were seen. The grains were isolated, and the cultured fungi were identified as Madurella mycetomatis based on morphology. Using the M. mycetomatis specific PCR, amplicons of a different size than that of the M. mycetomatis type strain were obtained. Objective To determine the causative agent of the two black‐grain mycetoma cases and develop non‐culture‐based diagnostic tools to identify them to the species level. Methods The M. mycetomatis specific, the internal transcribed spacer (ITS) region, β‐tubulin (BT) and ribosomal binding protein 2 (RBP2) PCRs were used to confirm the identity of the isolates. Genetic variation was established by amplification fragment length polymorphisms. To determine the antifungal susceptibility profile, the Sensititre™ YeastOne™ assay was used. To develop a species‐specific PCR primers were designed on the sequenced PCR amplicon from the M. mycetomatis specific PCR. Results By analyzing the ITS, BT and RBP2 regions the isolates were identified as Madurella pseudomycetomatis. The isolates from father and son were similar but not identical to M. pseudomycetomatis from Venezuela and one from an unknown origin. Madurella pseudomycetomatis isolates were inhibited by itraconazole, posaconazole and voriconazole but showed increased MIC values for amphotericin B and fluconazole. They were not inhibited by the echinocandins and five flucytosine. The two patients were treated with itraconazole resulting in cure for the father while the son was lost to follow‐up. The species‐specific PCR developed for M. pseudomyceotmatis was discriminative and specific. Conclusion Madurella pseudomycetomatis is genetically diverse with same susceptibility profile as M. mycetomatis and causes eumycetoma in Latin America. The M. pseudomycetomatis specific PCR can be used to identify this causative agent to the species level; however, this needs to be validated in an endemic setting.
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Affiliation(s)
- B Nyuykonge
- Department of Medical Microbiology and Infectious Diseases, Erasmus MC University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - C H W Klaassen
- Department of Medical Microbiology and Infectious Diseases, Erasmus MC University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - W H A Zandijk
- Department of Medical Microbiology and Infectious Diseases, Erasmus MC University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - G S de Hoog
- Westerdijk Fungal Biodiversity Institute, Utrecht, The Netherlands
| | - S A Ahmed
- Westerdijk Fungal Biodiversity Institute, Utrecht, The Netherlands.,Faculty of Medical Laboratory Sciences, University of Khartoum, Khartoum, Sudan
| | - M Desnos-Ollivier
- Molecular Mycology Unit, CNRS UMR 2000, National Reference Center for Invasive Mycoses & Antifungals, Institut Pasteur, Paris, France
| | - A Verbon
- Department of Medical Microbiology and Infectious Diseases, Erasmus MC University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - A Bonifaz
- Hospital General de México Dr Eduardo Liceaga, Mexico City, Mexico
| | - W W J van de Sande
- Department of Medical Microbiology and Infectious Diseases, Erasmus MC University Medical Center Rotterdam, Rotterdam, The Netherlands
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