Mycetoma, a chronic subcutaneous infection caused by bacterial or fungal species from soil and water, presents a diagnostic challenge due to its rarity and diverse clinical manifestations. Predominantly affecting male workers in endemic regions, mycetoma typically manifests as painless swelling evolving into purulent lesions with draining sinuses in the extremities. Although historically uncommon in regions like North America, rising immigration and international travel have led to an increased prevalence, necessitating heightened clinical suspicion. Early diagnosis is crucial to prevent severe complications such as limb loss and septicemia. This case report details the diagnosis and management of chronic actinomycetoma due to Nocardia spp. in a Guatemalan immigrant landscaper and emphasizes the importance of comprehensive understanding and timely intervention in mycetoma cases.

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.

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.

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Mycetoma is a chronic discharging infection involving the skin, subcutaneous tissue, fascia, and bone, which is endemic in tropical and subtropical countries. We report a rare case of mycetoma localized on the foot of a patient living in a country with a temperate climate. A 32-year-old male patient presented with painless swelling in the right foot. He had undergone surgery 3 years ago with the same complaints. Magnetic resonance imaging revealed a 90 × 65 × 37 mm cystic soft tissue lesion in the posterior of the right ankle. Histological analysis identified the fungus. Extensive resection was performed. Mycetoma is characterized by chronic granulomatous inflammatory response, often associated with sinus tract formations due to fungal (eumycetoma) or bacterial (actinomycetoma) organisms. Here we provide a literature review and highlight the importance of increasing awareness toward mycetoma, particularly in non-endemic regions.

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

Mycetoma is a chronic infectious disease endemic in sub-Saharan Africa (SSA), India and parts of South and North America. The epidemiologic profile of the disease in Egypt, which neighbours SSA, has not been explored previously. Therefore we conducted a scoping review of the literature on mycetoma in Egypt. We searched the literature comprehensively on MEDLINE and Google Scholar using free-text words and Medical Subject Headings and terms. Both published and non-peer-reviewed (grey literature) articles were included. The initial search identified 133 reports. Of these, only eight were found to be relevant and were included in the study. The total number of mycetoma patients was 59, reported between 1949 and 2015. There was a predilection for eumycetoma (44 of 59) patients (75%), while actinomycetoma constituted 15 patients (25%). Six patients were female, 28 were male and 25 were unreported. Children and adolescents constituted 3 of 59 (5%), 52 (88%) were adults and age was not provided for 4 patients. Only four patients (7%) were non-autochthonous. The incidence of mycetoma in Egypt is higher than previously reported. Egypt is probably a low-endemic country. An accurate estimate of the prevalence and epidemiology of mycetoma necessitates further research collaboration.

The objective of this study was to describe the epidemiological and clinical aspects as well as the therapeutic methods of mycetomical lesions.
This was a longitudinal retrospective study, which included all patients treated for mycetoma from January 2016 to December 2018 including two years of recruitment and one year of monitoring (2019). The study concerned 19 patients who were hospitalized and treated in the department of surgery.
Patients represented 2.3% of hospitalizations and consisted of 11 males and 8 females with an average age of 38 years with extremes of 15 - 70 years, and an average time between the onset of symptoms and presentation to the hospital of 10 years (range 1 - 40 years). Eight livestock breeders and seven farmers were concerned, 14 of whom have started the disease after trauma. The foot was involved in 13 patients. Twelve suffered from osteoarticular lesions. Black grains were present in 16 cases attributed to Madurella sp. We performed 12 amputations, six carcinological ablation to which specific local treatments were added (thin skin graft in two patients, fasciocutaneous flap in one patient and directed healing in the others) and local treatment in the last case.
Mycetoma should be discussed and diagnosed at an early stage in predisposed patients particularly in farmers and breeders. Prevention is necessary; it is based on wound disinfection and wearing safety shoes.

Background Mycetoma is widespread in Yemen; however, there are only a few documented reports on the entity from this geographical area. Methods A prospective study of 184 cases of mycetoma (male 145 and female 39) from different regions of north-western Yemen was conducted between July 2000 and May 2014. Clinical profile was recorded in a standardized protocol. The diagnosis was based on clinical features, X-ray studies, examination of grains, and histopathology. Results Eumycetoma was diagnosed in 129, caused by Madurella mycetomatis in 124, Leptosphaeria senegalensis in one and pale grain fungus in four, whereas actinomycetoma occurred in 55, caused by Streptomyces somaliensis in 29, Actinomadura madurai in nine, Actinomadura pelletieri in one, and Nocardia in sixteen. Eumycetoma cases were treated with prolonged course of antifungal drugs, mostly ketoconazole, with itraconazole being used in four patients, along with excision or debulking. Results were better when antifungal drugs were given two to three months before surgery and in those who received itraconazole. Actinomycetoma cases were initially treated with co-trimoxazole monotherapy; later streptomycin was added in 30 cases. Six patients who did not show adequate improvement and two others from the start were treated with modified Welsh regimen and with good results. Limitations Identification of different causative agents was done by histopathology and could not be reconfirmed by culture. Conclusion Mycetoma is widespread in north-western Yemen with a higher incidence of eumycetoma and a majority of the cases were caused by Madurella mycetomatis. Modified Welsh regimen in actinomycetoma and itraconazole with excision in eumycetoma showed the best results.

BACKGROUND: Mycetoma is a neglected tropical disease that commonly affects the lower extremity. The disease is attributed to subcutaneous granulomatous inflammation leading to distinct clinical features of gradual painless swelling accompanied by nodules and drains. Orbital mycetoma is an extremely rare entity of the disease. We reported the clinical presentation, diagnosis, and surgical outcomes in a case of orbital mycetoma with cranial extension.
METHODS: A 25-years-old male complained of left eye protrusion for 8 years, followed by complete loss of vision on the left eye for 7 years and eventually left eye pain for the last year. The left eye was displaced anteriorly and inferiorly with normal oculomotor, abducent, and trochlear examination. Brain CT scan showed an increase in orbital bone thickness with extension to the anterior cranial base, middle cranial base, and the orbital process of the zygomatic bone. MRI revealed a large lesion involving the left frontotemporal region with extension to left orbit, left posterior ethmoid air cells, and left temporal suprasellar region. The lesion was homogenously enhanced with contrast. The patient underwent a left orbitozygomatic cranitomy for resection of the lesion. However, total resection was inapplicable due to the extension of the bony lesion up to the petrous bone. Cranioplasty was performed by titanium mesh.
CONCLUSIONS: Mycetoma is a chronic inflammatory disease affecting subcutaneous tissues commonly in the lower limbs. The disease can be caused by fungi (Eumycetoma) or bacteria (Actinomycetoma). Orbital mycetoma is an extremely rare entity of the disease. However, it is commonly associated with the cranial extension. Early diagnosis and prompt surgical and medical treatment are the keys to good outcomes.