Host genetic susceptibility to mycetoma

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.

Epidemiologic Aspects of Mycetoma in Africa

Mycetoma is a chronic, disabling infection caused by fungi or actinomycetes that affects the disadvantaged rural populations of arid tropical regions. The identification of etiological agents is long, difficult, and often imprecise or unsuccessful. Recently developed molecular methods can be used to identify causal agents at the species level. However, diagnosis can only be implemented in specialized laboratories. For these reasons, the distribution of causal agents in endemic African countries remains approximate. It is known that the pathogenic organisms of mycetoma are present in the environment, introduced as a result of injuries or trauma. There are still unknowns concerning the natural habitats of agents and the mode of infection. A potential association between mycetoma and acacia was uncovered in Sudan, allowing the elaboration of a risk map of the country. A new hypothesis for the mode of contamination involves the intervention of an intermediate host. The first surveys in Sudanese endemic villages gave a higher prevalence than the previous estimates, indicating that the prevalence of mycetoma in endemic African countries has previously been underestimated.

Role of socioeconomic factors in developing mycetoma: Results from a household survey in Sennar State, Sudan

BACKGROUND

Mycetoma is a chronic, progressively destructive disease of subcutaneous tissues and bones caused by certain species of bacteria or fungi. We conducted a cross-sectional community-based study alongside mapping of mycetoma in five administrative units with high mycetoma endemicity in the Eastern Sennar Locality, Sennar State, Sudan.

METHODS

A household survey was administered which included questions about the household members, household characteristics, economic activity and history of mycetoma. A clinical examination was conducted on all members of the household. If mycetoma was suspected, an individual questionnaire was completed collecting demographic, clinical and epidemiological data as well as information on the use of health care and associated costs. Geographical coordinates and photos of the lesions were taken, and the affected persons were referred to the medical centre for confirmation of the diagnosis and treatment. We compared the characteristics of households with confirmed cases of mycetoma with those without confirmed cases, and individuals with confirmed mycetoma with those in whom mycetoma was not confirmed.

RESULTS

In total 7,798 households in 60 villages were surveyed; 515 suspected cases were identified and 359 cases of mycetoma were confirmed. Approximately 15% of households with mycetoma had more than one household member affected by this disease. Households with mycetoma were worse off with respect to water supply, toilet facilities, electricity and electrical appliances compared to the survey households. Only 23% of study participants with mycetoma had sought professional help. Of these, 77% of patients travelled an average of six hours to visit a medical facility. More than half of patients had to pay towards their treatment. The estimated average cost of treatment was 26,957 Sudanese pounds per year (566 US dollars, exchange rate 2018).

CONCLUSIONS

Results of this survey suggest that agricultural practices and reduced access to sanitation and clean water can be risk factors in developing mycetoma. Poor access to health care and substantial financial costs were barriers to seeking treatment for mycetoma.

Chronic Painless, Multiple Papulo-Nodular Skin Lesion at Foot Resembles Mycetoma Infection (Madura Foot): A Case Report

Madura foot is a chronic, progressively destructive bacterial or fungal infection of the subcutaneous tissues, which may affect skin, muscle, and bone. It is endemic in tropical and subtropical areas known as the "Mycetoma belt" between latitude 30°N and 15°S. Mycetoma is prevalent in the poor population living in remote areas of developing countries that lack proper reporting system and management. The World Health Organization recognized mycetoma as a neglected tropical disease back in 2016. Though the diagnosis is challenging, early detection and proper treatment can reduce morbidity and provide a promising outcome. We report a case of chronic painless, multiple papulo-nodular skin lesions at the foot that resembles mycetoma infection which was detected early and recovered with a satisfactory outcome with proper treatment.

A study of 87 mycetoma patients seen at three health facilities in Nouakchott, Mauritania

BACKGROUND

Mycetoma is a chronic, progressive and destructive inflammatory disease that affects the skin, subcutaneous and other tissues. The objective of this study was to identify all cases of mycetoma diagnosed in three health facilities in Nouakchott, Mauritania during 2016-2018.

METHODS

This retrospective hospital-based study was conducted at the Dermatology, Orthopedics, Mycology and Pathology departments of the National Hospital Center of Nouakchott, the Military Hospital of Nouakchott and the National Institute for Research in Public Health of Nouakchott.

RESULTS

Eighty-seven patients were included in this study. They comprised 65 male patients (74.71%) and 22 females (25.28%) with a gender ratio of 4:1. The mean age was 41.87 y and ages ranged from 14 to 70 y. The most common age group was 40-45 y (11%). The foot was the most frequently affected site seen in 60 patients (69%), followed by ankle and hand with 6 patients each (7%). In the study, 56 patients (64%) had regional lymphadenopathy. Forty-nine patients (56%) had bone involvement. Thirty-two patients (37%) had medical treatment. Twenty-seven patients (87%) received fluconazole and four patients (13%) had co-trimoxazole treatment.

CONCLUSION

The mycetoma patients seen in these three centres were mainly male farmers from rural areas. The lesions were seen mainly in the lower limbs and the majority had bone involvement radiologically.

Mycetoma spatial geographical distribution in the Eastern Sennar locality, Sennar State, Sudan

BACKGROUND

Mycetoma is a unique neglected tropical disease caused by a substantial number of different fungi or bacteria. Many of the disease's epidemiological characteristics are an enigma. Hence, understanding the spatial geographic distribution of mycetoma may clarify the association between the local environmental indicators, the spatial geographical distribution of mycetoma and its epidemiology.

METHODS

This study set out to determine the spatial geographical distribution of mycetoma in the Eastern Sennar locality, Sennar State, one of the highly endemic states in Sudan. It included 594 patients with confirmed mycetoma seen at the Mycetoma Research Centre, University of Khartoum, Khartoum, Sudan, from 1991 to 2020. The spatial geographical distribution of these mycetoma patients was studied. The study area geographic information system data, which included geological, soil, temperature and land cover details, were collected in different geographic information forms. Different geographical analytical techniques were used.

RESULTS

The patients' demographic characteristics were similar to those of the general characteristics of mycetoma patients in Sudan. Eumycetoma was the predominant type of mycetoma encountered in the studied patients. The data studied showed that most patients were located in the southern part of the locality along the Blue Nile river. The study showed an association between patients' spatial geographical distribution and soil types. Most patients' localities had light clay soil (475 patients [80%]), followed by sandy loam soil (79 [13%]) then loam soil (40 [6.71%]). Also, 85% of patients' localities had the same land cover and vegetation. There was no significant correlation between patients' localities with temperature or any other geological characteristic.

CONCLUSION

The present study showed certain associations between mycetoma spatial geographical distribution and certain environmental indicators. However, a further in-depth study to provide greater insight into the disease's epidemiological characteristics is needed.

Global scientific research progress in mycetoma: a bibliometric analysis

BACKGROUND

Mycetoma is a neglected tropical disease that attracts little attention in regard to research and publications and hence this study was undertaken to determine the trends and global scientific research output in mycetoma-related fields.

METHODS

Mycetoma data were retrieved from the Web of Science (WoS) and Scopus databases. The MeSH Browser was used to extract relevant keywords. Biblioshiny software (R-studio cloud), VOSviewer v. 1.6.6 and SPSS software were used for data management.

RESULTS

Research trends on mycetoma increased globally from 1999 to 2020. The results were 404 documents (4444 citations) in WoS and 513 documents (5709 citations) in Scopus, and the average number of citations per article was 11 in WoS and 11.13 in Scopus. There was a significant association between the total number of citations and the total citations per year in both WoS (r=0.833, p<0.0001) and Scopus (r=0.926, p<0.0001). Sudan, India, the Netherlands and Mexico were the top-ranking productive countries for mycetoma publications in WoS, while India, the USA and Mexico were the top-ranking countries in Scopus. Articles on mycetoma were mainly published in PLoS Neglected Tropical Diseases, the International Journal of Dermatology and the Journal of Clinical Microbiology. A. H. Fahal from the Mycetoma Research Centre, University of Khartoum, Sudan, had the highest number of citations in mycetoma research during 1999-2020, followed by W. W. J. van de Sande from the Erasmus Medical Centre, University of Rotterdam, the Netherlands, during 2003-2020.

CONCLUSION

The analysis provides insight into a global overview of Mycetoma research. In addition, the analysis holds a better understanding of the development trends that have emerged in Mycetoma over the past 21 years, which can also offer a scientific reference for future research.

Eumycetoma of the Foot due to Fusarium solani in a Person with Diabetes Mellitus: Report of a Case and Review of Literature

Eumycetomas are chronic suppurative granulomas caused by fungi characterised by invasive tumefactive lesions, sinuses and discharging grains. Herein, we describe a case of pedal eumycetoma due to Fusarium solani sensu stricto in a person with diabetes mellitus. A 45-year-old gentleman presented with an insidious onset swelling over his right foot with nodules and discharging grains. He had received itraconazole and anti-tuberculous therapy elsewhere, without response. Re-evaluation included a biopsy which confirmed eumycetoma and newly diagnosed diabetes. Surgical excision followed by histopathological, microbiological and multigene sequencing analyses [translation elongation factor, calmodulin and internal transcribed spacer region of rDNA] of the mould on culture were performed. Histopathology revealed septate fungal hyphae amidst a dense inflammatory infiltrate (Splendore-Hoeppli) reaction. Oral voriconazole was started and good glycemic control attained. Tissue growth sequences showed > 99% similarity with Fusarium solani sensu stricto. Antifungal susceptibility testing showed lowest MIC to voriconazole (0.5 mg/L). The patient showed excellent response to combined therapeutic modality with a near-complete resolution in size of lesion and obliteration of sinuses following 4 months of therapy and is planned for prolonged voriconazole therapy till complete radiological resolution. Diabetes predisposes to fungal infections of foot but eumycetomas are uncommon. Combined surgery and antifungals can improve morbidity and avoid amputations.

Actinomycetoma by Actinomadura madurae: Clinical Characteristics and Treatment of 47 Cases

Context:

Mycetoma is a chronic, granulomatous disease caused by fungi (eumycetoma) or aerobic filamentous actinomycetes (actinomycetoma). Actinomadura madurae is one of the most frequent actinomycetes.

Aim:

The study aims to provide an update on clinical, diagnostic, therapeutic, and outcome data for patients with actinomycetoma in a single center in Mexico.

Settings and Design:

This was a retrospective study of 47 cases diagnosed with actinomycetoma.

Subjects and Methods:

The cases were selected from a total of 536 mycetoma obtained during 35 years (from 1985 to 2019). Clinical data were retrieved from the clinical records of our department. Microbiological data were obtained from our Mycology laboratory.

Statistical Analysis:

Frequencies and percentages were used for categorical variables. Normality was determined with the Kolmogorov–Smirnov test. We used means and medians to describe the variables.

Results:

Forty-seven patients with actinomycetoma were included; female:male ratio 1.9:1; median age 38 years. The foot was the most affected region in 76.5% of cases. The bone invasion was observed in 89%. The time between symptoms onset and diagnosis was 5.5 years. Grain detection by direct examination was positive in 95% of cases. The most commonly used, as well as the most effective treatment scheme was streptomycin + sulfamethoxazole-trimethoprim with dapsone. Sixty-three percent (30 patients) achieved clinical and mycological cure, and 10.6% (5 patients) had treatment failure.

Conclusions:

We highlight the importance of designing therapeutic strategies to standardize treatments and gain more experience to improve the care of these patients.