Role of special stains in identification of fungi in eumycetoma among Sudanese patients in Soba University Hospital

Background: Mycetoma is a unique neglected tropical disease caused by a substantial number of microorganisms of fungal or bacterial origins. Identification of the causative organism and the disease extension are the first steps in the management of the affected patients and predicting disease treatment outcome and prognosis. Objectives: To determine the role of special stain in identification of fungi in eumycetoma among Sudanese patients at Soba University Hospital. Method: This descriptive cross- sectional study was conducted of Fifty-nine archival formalin fixed paraffin- embedded tissue blocks, four identical sections from each archival paraffin-embedded tissue block were obtained and stained with routine H&E and special stains {Periodic-Acid-Schiff (PAS) and Grocott-Gomori silver (GMS) and Gridley stain}, then the collected data was analyzed using SPSS version 23.0. Results: The use of special stains especially periodic acid Schiff’s and Grocott methenamine-silver (GMS) stain are of value (specific and sensitive) in identifying the fungal hyphae and yeast of eumycetoma. Mycetoma is more commonly reported in males than females; also mycetoma is most common in young adults (16–40 years old) and is uncommon in children. No significant relationship was demonstrated between diagnosis and variables (gender, age). Type I and II was the commonest type of the host tissue reaction encountered in this study. Conclusion: Results showed that GMS and PAS had the ability to stain both fungal hyphae and yeast in compare to Gridley’s stain which had some limitations to stain fungal structures

The Combination of Amoxicillin-Clavulanic Acid and Ketoconazole in the Treatment of Madurella mycetomatis Eumycetoma and Staphylococcus aureus Co-infection

Eumycetoma is a chronic progressive disabling and destructive inflammatory disease which is commonly caused by the fungus Madurella mycetomatis. It is characterized by the formation of multiple discharging sinuses. It is usually treated by antifungal agents but it is assumed that the therapeutic efficiency of these agents is reduced by the co-existence of Staphylococcus aureus co-infection developing in these sinuses. This prospective study was conducted to investigate the safety, efficacy and clinical outcome of combined antibiotic and antifungal therapy in eumycetoma patients with superimposed Staphylococcus aureus infection. The study enrolled 337 patients with confirmed M. mycetomatis eumycetoma and S. aureus co-infection. Patients were allocated into three groups; 142 patients received amoxicillin-clavulanic acid and ketoconazole, 93 patients received ciprofloxacin and ketoconazole and 102 patients received ketoconazole only. The study showed that, patients who received amoxicillin-clavulanic acid and ketoconazole treatment had an overall better clinical outcome compared to those who had combined ciprofloxacin and ketoconazole or to those who received ketoconazol

Madurella mycetomatis Is Highly Susceptible to Ravuconazole

The current treatment of eumycetoma utilizing ketoconazole is unsatisfactory because of high recurrence rates, which often leads to complications and unnecessary amputations, and its comparatively high cost in endemic areas. Hence, an effective and affordable drug is required to improve therapeutic outcome. E1224 is a potent orally available, broad-spectrum triazole currently being developed for the treatment of Chagas disease. E1224 is a prodrug that is rapidly converted to ravuconazole. Plasma levels of E1224 are low and transient, and its therapeutically active moiety, ravuconazole is therapeutically active. In the present study, the in vitro activity of ravuconazole against Madurella mycetomatis, the most common etiologic agent of eumycetoma, was evaluated and compared to that of ketoconazole and itraconazole. Ravuconazole showed excellent activity with MICs ranging between ≤0.002 and 0.031 μg/ml, which were significantly lower than the MICs reported for ketoconazole and itraconazole. On the basis of our findings, E1224 with its resultant active moiety, ravuconazole, could be an effective and affordable therapeutic option for the treatment of eumycetoma

Proteomic analysis of the processes leading to Madurella mycetomatis grain formation in Galleria mellonella larvae

Mycetoma is a neglected chronic and granulomatous infection primarily associated with the fungal pathogen Madurella mycetomatis. Characteristic of this infection is the formation of grains. However, the processes leading to grain formation are not known. In this study, we employed a proteomic approach to characterise M. mycetomatis grain formation in Galleria mellonella larvae and map the processes leading to grain formation over time. For this, at 1 day, 3 days and 7 days post-inoculation, proteins from grains and hemolymph were extracted and analysed by label-free mass spectrometry. A total of 87, 51 and 48 M. mycetomatis proteins and 713, 997, 18 G. mellonella proteins were found in grains on day 1, 3 and 7 post-inoculation respectively. M. mycetomatis proteins were mainly involved in cellular metabolic processes and numerous enzymes were encountered. G. mellonella proteins were primarily involved in the nodulation process. The proteins identified were linked to nodulation and grain formation and four steps of grain formation were identified. The results of this proteomic approach could in the future be used to design novel strategies to interfere with mycetoma grain formation and to combat this difficult to treat infection

The In Vitro Antifungal Activity of Sudanese Medicinal Plants against Madurella mycetomatis, the Eumycetoma Major Causative Agent

Eumycetoma is a debilitating chronic inflammatory fungal infection that exists worldwide but it is endemic in many tropical and subtropical regions. The major causative organism is the fungus Madurella mycetomatis. The current treatment of eumycetoma is suboptimal and characterized by low cure rate and high recurrence rates. Hence, an alternative therapy is needed to address this. Here we determined the antifungal activity of seven Sudanese medicinal plant species against Madurella mycetomatis. Of these, only three species; Boswellia papyrifera, Acacia nubica and Nigella sativa, showed some antifungal activity against M. mycetomatis and were further studied. Crude methanol, hexane and defatted methanol extracts of these species were tested for their antifungal activity. B. papyrifera had the highest antifungal activity (MIC50 of 1 ug/ml) and it was further fractionated. The crude methanol and the soluble ethyl acetate fractions of B. papyrifera showed some antifungal activity. The Gas-Liquid-Chromatography hybrid Mass-Spectrophotometer analysis of these two fractions showed the existence of beta-amyrin, beta-amyrone, beta-Sitosterol and stigmatriene. Stigmatriene had the best antifungal activity, compared to other three phytoconstituents, with an MIC-50 of 32 μg/ml. Although the antifungal activity of the identified phytoconstituents was only limited, the antifungal activity of the complete extracts is more promising, indicating synergism. Furthermore these plant extracts are also known to have anti-inflammatory activity and can stimulate wound-healing; characteristics which might also be of great value in the development of novel therapeutic drugs for this chronic inflammatory disease. Therefore further exploration of these plant species in the treatment of mycetoma is encouraging

The Mycetoma Knowledge Gap: Identification of Research Priorities

Mycetoma is a tropical disease which is caused by a taxonomically diverse range of actinomycetes (actinomycetoma) and fungi (eumycetoma). The disease was only recently listed by the World Health Organization (WHO) as a neglected tropical disease (NTD). This recognition is the direct result of a meeting held in Geneva on February 1, 2013, in which experts on the disease from around the world met to identify the key research priorities needed to combat mycetoma. The areas that need to be addressed are highlighted here. The initial priority is to establish the incidence and prevalence of the disease in regions where mycetoma is endemic, prior to determining the primary reservoirs of the predominant causal agents and their mode of transmission to susceptible individuals in order to establish novel interventions that will reduce the impact of the disease on individuals, families, and communities. Critically, economical, reliable, and effective methods are required to achieve early diagnosis of infections and consequential improved therapeutic outcomes. Molecular techniques and serological assays were considered the most promising in the development of novel diagnostic tools to be used in endemic settings. Improved strategies for treating eumycetoma and actinomycetoma are also considered

Genome sequence of Madurella mycetomatis mm55, isolated from a human mycetoma case in Sudan

We present the first genome sequence for a strain of the main mycetoma causative agent, Madurella mycetomatis. This 36.7-Mb genome sequence will offer new insights into the pathogenesis of mycetoma, and it will contribute to the development of better therapies for this neglected tropical disease