Epidemiological observations and management challenges in extrapedal mycetoma: A three-decade review of 420 cases.

Mycetoma is a serious, destructive, disfiguring chronic granulomatous inflammatory disease affecting the subcutaneous tissues that spread to involve the skin, deep tissues and bone. The disease predominately affects the limbs, and extrapedal mycetoma is rarely reported. The reported extrapedal ones are characterised by high morbidity and mortality. This communication reports on 420 patients with extrapedal mycetoma seen and managed at the Mycetoma Research Centre (MRC), University of Khartoum, between January 1991 and December 2021. In this descriptive, cross-sectional, hospital-based study, the electronic records of all mycetoma-confirmed patients seen during the study period were carefully and meticulously reviewed. The confirmed patients with extrapedal mycetoma were included in this study. The study included 420 patients with extrapedal mycetoma, 298 (70.7%) had eumycetoma, and 122 (29.3%) had actinomycetoma. There were 343 male patients (81.7%) and 77 (18.3%) females, with a male-to-female ratio of 4:1. Their ages ranged between 1.5 and 95 years, with a median of 28 years. Most of the patients were students and farmers. The majority of patients were from El Gezira, North Kordofan, and the White Nile States. Mycetoma was painful in 21%, and a family history of mycetoma was recorded in 11.5% of patients. The buttocks (37.9%) and head and neck (16.9%) were affected most. Less frequently affected sites were the trunk and back (12%) each, abdominal and chest walls (4.5%) each and loin (1%). The prominent clinical presentation findings were multiple sinuses discharging grains (55%), massive swellings (46%), and lymphadenopathy (11.5%). Less commonly observed clinical findings were local hyperhidrosis (5.3%) and dilated tortuous veins close to mycetoma lesions (0.5%). The study showed that 204 patients (48.6%) had clinical improvement in terms of decreased lesion size and healing of sinuses following medical therapy. Sixty-six patients (15.7%) had no noticeable improvement. The lesion continued progressing despite treatment in 44 patients (10.5%). In the study, 118 patients were on regular follow-up, and in this group, a cure was documented in 25 patients (21.1%) with eumycetoma and 23 (19.4%) with actinomycetoma. Post-operative recurrence among eumycetoma patients was 40%, with a 1% mortality rate. The treatment outcome was unsatisfactory, characterised by a low cure rate, high recurrence (40%) and follow-up dropout (57%) rates. This emphasises the importance of early case detection and management, objective health education programmes and thorough patient counselling to urge people to seek treatment early and reduce dropouts.

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

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

Actinomycetoma in a patient with pre-existing sensorineural hearing loss: a linezolid-based treatment paradigm.

Mycetoma is a chronic granulomatous infectious disease with a triad of subcutaneous swelling, discharging sinuses and the presence of granules. The infection may occur following minor trauma or penetrating thorn injury. We report a case of a man in his 40s with a history of thorn prick 9 years ago, followed by the formation of painless discharging sinuses on the right foot for the past 2 years. Clinical, local epidemiological, histopathological examination and Gram stain confirmed the diagnosis of actinomycetoma. Prior to initiating the Welsh regimen, a pretreatment assessment of the patient's auditory function was conducted through pure tone audiometry, indicating the existence of pre-existing high-frequency bilateral sensorineural hearing loss. The patient was treated with linezolid as an alternative to amikacin, at a dosage of 600 mg two times per day, leading to complete resolution within 3 weeks. This underscores linezolid's efficacy as a safe and cost-effective alternative for actinomycetoma, without causing ototoxic side effects.

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.

Evaluation of a computational model for mycetoma-causative agents identification.

BACKGROUND: The therapeutic strategy for mycetoma relies heavily on the identification of the causative agents, which are either fungal or bacterial. While histopathological examination of surgical biopsies is currently the most used diagnostic tool, it requires well-trained pathologists, who are lacking in most rural areas where mycetoma is endemic. In this work we propose and evaluate a machine learning approach that semi-automatically analyses histopathological microscopic images of grains and provides a classification of the disease as eumycetoma or actinomycetoma. METHODS: The computational model is based on radiomics and partial least squares. It is assessed on a dataset that includes 890 individual grains collected from 168 patients originating from the Mycetoma Research Centre in Sudan. The dataset contained 94 eumycetoma cases and 74 actinomycetoma cases, with a distribution of the species among the two causative agents that is representative of the Sudanese distribution. RESULTS: The proposed model achieved identification of causative agents with an accuracy of 91.89%, which is comparable to the accuracy of experts from the domain. The method was found to be robust to a small error in the segmentation of the grain and to changes in the acquisition protocol. Among the radiomics features, the homogeneity of mycetoma grain textures was found to be the most discriminative feature for causative agent identification. CONCLUSION: The results presented in this study support that this computational approach could greatly benefit rural areas with limited access to specialized clinical centres and also provide a second opinion for expert pathologists to implement the appropriate therapeutic strategy.

Mycetoma case series in Somalia.

Mycetoma is a suppurative chronic bacterial or fungal disease inoculated into the body by minor trauma which may penetrate from subcutaneous tissue to bone. Although the lower extremities are most commonly affected, rare forms can also be seen from time to time. The diagnostic triad of swelling in the affected area, multiple sinus formation, and purulent discharge with grains are typical. Definitive diagnosis is made by isolation of the causative pathogen, radiologic imaging, and histopathologic examination. Antifungal and antibacterial options are applied together with surgery. Our aim in this case series is to report and analyze 10 rare cases of mycetoma.

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.

Invasive Eumycotic mycetoma of the nasal septum in a post-dialysis patient: A case report.

BACKGROUND: Mycetoma is a slowly progressive chronic granulomatous disease of the skin, subcutaneous tissue, and underlying or adjacent cartilage or bone. Most commonly involves the foot region. Other parts such as the knee, arm, leg, head, neck, thigh, perineum, chest, abdominal walls, facial bones, mandible, paranasal sinuses, eyelid, vulva, orbit, and scrotum are seldom affected. METHODS: This is a rare presentation of Eumycotic mycetoma involving the nasal septum. Surgical debridement is done under local anesthesia. Histopathological examination of debrided specimen guided in the diagnosis and treatment. RESULTS: Histopathological examination is the one that confirms the diagnosis and rules out the other granulomatous conditions and fungal rhinitis causing septal perforation. CONCLUSIONS: In an immunocompromised state, we know that mucormycosis and zygomycosis are known to cause aggressive complications like orbital invasion and palatal perforation by vascular route. However, other fungal infections also can lead to septal perforations whenever there is lessened resistance by the mucosal barrier due to trauma (nasal intubations).

Fungal mycetoma and pregnancy: An association with costly and difficult management, about a case.

Mycetomas are endemic diseases in tropical and sub-tropical countries of Africa, Asia and America, mainly affecting rural populations living below the poverty line. We report a particular case of a mycetoma associated with pregnancy whose evolution was good, but at the cost of significant financial expenses. This was a 39-year-old woman who developed a fungal mycetoma due to Madurella mycetomatis from the ingunocrural region. The patient had to develop several previous pregnancies on this site of mycetoma, the outcome of which was favorable. The last pregnancy was accompanied by an aggravation of the mycetoma in the form of polyfistulized inflammatory swelling of the right inguino-crural region emitting black grains. Magnetic Resonance Imaging (MRI) of the region showed invasion of the adductor muscles at the level of the root of the thigh on its antero-internal side with no sign of pelvic extension or underlying bone lesion. The patient was treated by surgery associated with antifungal treatment. The evolution was favorable for pregnancy and mycetoma.

First report on mycetoma in Turkana County-North-western Kenya.

Mycetoma is one of the six Neglected Tropical Diseases that are prevalent in Turkana County (northwest Kenya). The aim of the study was to estimate the prevalence of mycetoma in the county, as well as to describe the main causative agents involved in the disease using methods affordable locally. Based on the data collected by the team of cooperative medicine Cirugia en Turkana (Surgery in Turkana), a specific study for mycetoma was started during the 16th humanitarian medicine campaign in February 2019. Patients with suspected mycetoma were studied at the Lodwar County Referral Hospital (LCRH). After informing the patient and getting their consent, the lesions were examined and sampled (mainly by biopsy) and clinical data were recorded. Samples were washed in sterile saline solution and cut in fragments. Some of these were inoculated on Sabouraud Dextrose Agar, Malt Extract Agar, and diluted Nutrient Agar plates. One fragment of each sample was used for DNA extraction. The DNA and the rest of the fragments of samples were kept at -20°C. All cultures were incubated at room temperature at the LCRH laboratory. The DNA obtained from clinical samples was submitted to PCR amplification of the ITS-5.8S and the V4-V5 16S rRNA gene region, for the detection and identification of fungi and bacteria respectively. From February 2019 till February 2022, 60 patients were studied. Most of them were men (43, 74,1%) between 13 and 78 y.o. (mean age 37). Half of the patients were herdsmen but, among women 40% (6) were housewives and 26.7% (4) charcoal burners. Lesions were mainly located at the feet (87.9%) and most of the patients (54; 93.1%) reported discharge of grains in the exudate, being 27 (46.6%) yellow or pale colored and 19 (32.8%) of them dark grains. Culture of clinical samples yielded 35 fungal and bacterial putative causative agents. Culture and molecular methods allowed the identification of a total of 21 causative agents of mycetoma (39.6% of cases studied). Most of them (17) corresponded to fungi causing eumycetoma (80.9%) being the most prevalent the genus Madurella (7; 41.2%), with two species involved (M. mycetomatis and M. fahalii), followed by Aspergillus (2; 11.8%). Other minority genera detected were Cladosporium, Fusarium, Acremonium, Penicillium, and Trichophyton (5.9% each of them). Actinobacteria were detected in 19.1% of samples, but only Streptomyces somaliensis was identified as a known agent of mycetoma, the rest being actinobacteria not previously described as causative agents of the disease, such as Cellulosimicrobium cellulans detected in two of the patients. Although Kenya is geographically located in the mycetoma belt, to our knowledge this is the first report on mycetoma in this country from 1973, and the first one for Turkana County.

A surgeon's trial success of curing pedal eumycetoma.

Mycetoma is a chronic infection of underlying fungal (eumycetoma) or bacterial (actinomycetoma) origin. It is characterised by a clinical triad of tumour-like swelling, actively draining sinuses and macroscopic grains of characteristic colours.We the case of a 66-year-old woman on immunosuppressive therapy presenting with eumycetoma of the foot (Madura foot). The fungal organism cultured was Acrophialophora fusisporaThis case was managed with a combination of extensive surgical debridement, and packing with calcium sulfate (Stimulan) beads impregnated with vancomycin and voriconazole. As far as the authors are aware, this is a novel adjunct to the surgical treatment of deep fungal infection in the foot.Eumycetoma treated with surgery and oral antifungal therapy leads to cure rates of 25%-35%. This novel treatment seems to bear further investigation for the potential to improve cure rates. At 8 months follow-up, our patient appears to be making good progress with no current signs of recurrence.

Linezolid: a safer and effective substitute to aminoglycoside in the treatment of actinomycetoma by Nocardia species.

Actinomycetoma is chronic, suppurative, granulomatous infection caused by bacteria and requires prolonged antibiotic therapy preferrably in combinations. Nephrotoxicity is a common side effect of aminoglycosides used in the management of actinomycetoma. We report here two cases of actinomycetoma due to Nocardia species who received linezolid as a substitute to aminoglycosides after developing nephrotoxicity.

Genetic variability of the 16S rRNA gene of Nocardia brasiliensis, the most common causative agent of actinomycetoma in Latin America and the Caribbean.

Mycetoma is a neglected tropical disease (NTD) declared by the World Health Organization (WHO) in 2016. It is characterized by the progressive growth of nodules and granulomatous lesions on the legs, arms, and trunk. It is potentially disfiguring and causes disability or amputations in working-age people from marginalized areas. The causative agents can be fungi (eumycetoma) or actinobacteria (actinomycetoma), the latter being the most common in America and Asia. Nocardia brasiliensis is the most important causal agent of actinomycetoma in the Americas. Taxonomic problems have been reported when identifying this species, so this study aimed to detect the 16S rRNA gene variations in N. brasiliensis strains using an in silico enzymatic restriction technique. The study included strains from clinical cases of actinomycetoma in Mexico, isolated from humans and previously identified as N. brasiliensis by traditional methods. The strains were characterized microscopically and macroscopically, then subjected to DNA extraction and amplification of the 16S rRNA gene by PCR. The amplification products were sequenced, and consensus sequences were constructed and used for genetic identification and in silico restriction enzyme analysis with the New England BioLabs® NEBcutter program. All study strains were molecularly identified as N. brasiliensis; however, in silico restriction analysis detected a diversity in the restriction patterns that were finally grouped and subclassified into 7 ribotypes. This finding confirms the existence of subgroups within N. brasiliensis. The results support the need to consider N. brasiliensis as a complex species.

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

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

Mycetoma management and clinical outcomes: the Mycetoma Research Center experience.

BACKGROUND: Mycetoma is a chronic granulomatous inflammatory disease that affects the cutaneous and subcutaneous tissues, leading to gruesome complications if not treated early. As a neglected disease, it has received scant attention in developing curable drugs. Mycetoma treatment is still based on expert opinions in the absence of guidelines. METHODS: This descriptive, cross-sectional, hospital-based study aimed to determine and assess the disease treatment outcomes observed at Mycetoma Research Center, Sudan. RESULTS: In this study, 75% of patients had eumycetoma, all of whom were treated with itraconazole and 37.4% underwent surgical excision, while 25% of the patients had actinomycetoma, 99.2% of whom were treated with a combination of cotrimoxazole and amoxicillin-clavulanate. The cure rate was 12.7% and 14.3% for patients with eumycetoma and actinomycetoma, respectively. Only 6.1% of eumycetoma patients underwent amputation. Remarkably, no patient with actinomycetoma underwent an amputation. Small lesions (OR=10.09, p<0.001) and good follow-up (OR=6.81, p=0.002) were positive predictors of complete cure. In terms of amputation, history of surgical recurrence at presentation (OR=3.67, p=0.020) and presence of grains (OR=7.13, p=0.012) were positive predictors, whereas small lesions were negative predictors (OR=0.06, p=0.009). CONCLUSIONS: Treatment of mycetoma was suboptimal, with a low cure rate despite a long treatment duration. Complete cure has a significant association with small lesions and good follow-up.

Expansile Sphenoid Mycetoma Presenting With Headache and Galactorrhea.

This case report describes an immunocompetent woman in her 30s with daily vertex headaches over 13 months duration who developed spontaneous galactorrhea and was diagnosed with noninvasive fungal sinusitis.

Clinical triad with multi-biopsy histopathology as a reliable diagnostic marker of mycetomas: a retrospective review from a tertiary care center.

BACKGROUND: Mycetoma is a neglected tropical infectious disease which runs a prolonged and protracted course. Microbiological confirmation is diagnostic yet unreliable due to poor sensitivity and variable availability of culture facilities in resource poor settings. METHODS: A retrospective review was performed on electronic records (histopathology, microbiology, and radiology) of all patients who underwent skin biopsies with mycetoma as one of the clinical differential diagnoses from year 2016 to 2020. RESULTS: Out of 73 patients biopsied with a differential of mycetoma, 42 fit the clinical triad of swelling-sinuses-granules. After clinical, microbiological, pathological, and radiological correlation, 31 cases were of eumycetoma and seven were of actinomycetoma. Mean patient age was 37.58 ± 13.8 years with a male to female ratio 2.45 : 1 and mean disease duration of 11.31 ± 10.9 years. Histopathological findings revealed fungal hyphae in 18 cases and gram-positive bacteria in six cases. Fungal culture was positive in 13 cases with the three commonest organisms being Madurella mycetomatis in five cases, Fusarium and Aspergillus nidulans in two cases each. X-ray changes of soft tissue, bones, and joints were seen in 25 cases, and "dot-in-circle" sign was seen in eight of nine MRIs. CONCLUSION: Eumycetoma was more common than actinomycetoma in our setup, ratio being 4.43 : 1. A clinical triad of swelling, multiple sinuses and grainy discharge with any one diagnostic support (histopathology/radiology) is sufficient to make a definitive diagnosis of mycetoma in the absence of microbiological identification.

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

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

Identification of Differentially Expressed Genes in Nocardia brasiliensis Induced by Progesterone and Dihydrotestosterone Using Differential Display PCR.

Sex steroid hormones have an important physiological role in humans. They can also affect the gene expression of many organisms, including bacteria. In Mexico, Nocardia brasiliensis is the main causative agent of actinomycetoma, a granulomatous disease more frequent in men than women, which is thought to be related to a higher occupational risk in men. Therefore, it has been suggested that differences in clinical presentation could be related to sex steroid hormone levels. Attempting to explain the differences in actinomycetoma prevalence between men and women, in this work, the effect of progesterone and dihydrotestosterone on the genetic expression of N. brasiliensis was investigated using a differential display polymerase chain reaction assay. The results showed that both hormones affected the expression of genes encoding proteins related to central metabolism and hypothetical proteins with unknown functions. This study also demonstrated the utility of differential display in this modern era and provided a first approach to the effect of sex hormones on N. brasiliensis gene expression.