Mycetoma of the foot--diagnosis of the etiologic agent and surgical treatment

Mycetoma caused by Madurella mycetomatis in immunocompromised patients – a case report and systematic literature review

Abstract. The aim of this study was to review the available literature concerning Madura foot (“mycetoma”) caused by Madurella mycetomatis in immunocompromised patients. With a systematic literature search, we identified only three papers, describing a total of three immunocompromised patients. Hence, the clinical presentation and prognosis of the disease in this patient population have not yet been well described. In addition, we present a case from our institution, illustrating the complexity of the treatment of this rare disease. Although very rare in non-endemic countries, we emphasize that mycetoma should be included in the differential diagnoses of (immunocompromised) patients who have been residing in a geographical area where the disease is endemic and presenting with soft tissue inflammation of one of the extremities.

Identification of Streptomyces spp. in a clinical sample: always contamination? Results of a French Retrospective Study

Background

Streptomyces are environmental Gram-positive bacilli that can cause ubiquitous mycetoma and, more rarely, invasive infections. We describe the clinical relevance of Streptomyces spp. identified in human samples and characteristics of patients with invasive Streptomyces infections.

Methods

We conducted a retrospective (2006-2017) study of Streptomyces isolates identified in clinical samples in French microbiology laboratories. Streptomyces genus was confirmed by a specific 16S rRNA PCR and antibiotic susceptibility testing was performed by disk diffusion and trimethoprim-sulfamethoxazole MIC (E-test) if resistance was suspected. Patient characteristics, treatment and outcomes were collected. Invasive infection was defined as a positive culture from a sterile site with signs of infection but without cutaneous inoculation.

Results

Of 137 Streptomyces isolates, all were susceptible to amikacin (113/113) and linezolid (112/112) and 92.9% to imipenem (105/113). Using disk diffusion, 50.9% (57/112) of isolates were susceptible to trimethoprim-sulfamethoxazole but most of apparently-resistant isolates (25/36, 69.4%) tested by E-test were ultimately classified as susceptible. Clinical data were obtained for 63/137 (45.9%) isolates: 30 (47.6%) invasive infections, 8 (12.7%) primary cutaneous infections, 22 (34.9%) contaminations, 3 (4.7%) respiratory colonization. Patients with invasive infection were more frequently receiving corticosteroids than patients without invasive infection (11/30, 36.7% vs 2/25, 8.0%, P = 0.03) and at 6-months follow-up, 14 of them were cured, three had relapsed, four were dead and nine were lost to follow-up.

Conclusions

Half of the clinical samples that grew Streptomyces were from patients with invasive infection. In that case, antimicrobial therapy should include one or two antibiotics among linezolid, amikacin or imipenem.

Mycetoma in West Africa

BACKGROUND

Mycetoma is a neglected disease, which is socioeconomically important, and with the possibility of permanent disability in infected persons if not treated early. This is especially true in resource-limited settings such as West Africa, where there is a lack of facilities and skilled personnel to make a definitive laboratory diagnosis. Countries in West Africa have similar climatic conditions to Sudan. The majority of patients seek medical care very late, when there is already bone involvement, resulting in amputations. This results in poor capture of the true burden of the problem in the literature.

METHODS

A review of the literature revealed about 2685 documented cases in West Africa from 1929 to 2020; from 15 out of 16 countries, Senegal accounted for 74.1% (1943) of cases in the subregion.

RESULTS

The majority of lesions were found on the foot; however, other body parts were also reported. Rural dwellers accounted for most cases. Only 547 (20.4%) cases had identified isolates reported. Actinomycetoma accounted for 47.9% of cases, eumycetoma 39.7% and unidentified pathogens 12.4%. Actinomadura pelletieri was the predominant pathogen isolated (21.4%; 117 isolates).

CONCLUSION

There is a dire need for capacity building, provision of facility and health education to raise awareness of this debilitating disease in West Africa.

Treatment of Madura foot: a systematic review

REVIEW QUESTION/OBJECTIVE

The objective of this review was to determine the best available evidence on the most effective treatment of Madura foot.

INTRODUCTION

Madura foot or mycetoma is a chronic granulomatous soft-tissue infection that is endemic to several regions of Africa and Asia. It may be of fungal (eumycetoma) or bacterial (actinomycetoma) origin, warranting therapy with either antifungal or antibacterial medication as well as surgery. Without timely intervention, it often results in lifelong disability. However, it is unclear what regimes are most effective for treatment.

INCLUSION CRITERIA

This review considered studies that included individuals of all ages with Madura foot (actinomycetoma or eumycetoma) as confirmed by microbiological or histological studies. Studies that evaluated antibiotic and antifungal regimens (any drug, dosage, frequency, duration) as well as surgical interventions (wound debridement, advanced excision or limb amputation) for Madura foot were included. Outcomes of interest were disease resolution (as determined by complete healing of mycetoma lesion after treatment), recurrence (return of mycetoma lesion after successful treatment) and mortality. Although this review considered both experimental and epidemiological study designs for inclusion, only case series and individual case reports were identified and were therefore included in the review.

METHODS

A three-step search strategy, involving an initial search, a second more comprehensive search using identified keywords and a third search involving the reference lists of included articles, was utilized. Ten databases were searched. An additional 13 sources were searched for gray and/or unpublished literature. Included studies were assessed by two independent reviewers for methodological validity prior to inclusion in the review using standardized critical appraisal instruments from the Joanna Briggs Institute. Disagreements were resolved through discussion or with a third reviewer. A data extraction tool was used to extract data on interventions, populations, study designs and outcomes of significance to the review question. Statistical pooling was not possible, therefore a narrative synthesis was performed.

RESULTS

Thirty-one studies were included in the review (27 case reports and four case series). A total of 47 patients with Madura foot were analyzed. Twenty-five had eumycetoma, 21 actinomycetoma and one had both. Therapy involved varying dosages of sulfa drugs (co-trimoxazole and dapsone), amikacin and tetracyclines administered for the therapy of actinomycetoma with resolution of disease in all affected patients. The azole derivatives (itraconazole, ketoconazole, voriconazole, fluconazole and miconazole) as well as co-trimoxazole were the most commonly employed drugs for eumycetoma, with resolution of disease in 88% of included patients. Surgery was performed in a total of 21 patients with resolution of disease in all cases. The overall resolution rate following therapy was 95.7%.

CONCLUSION

Therapy for Madura foot is informed by case series and case reports which provide low level evidence for practice. Antimicrobials in conjunction with surgery lead to resolution of disease.

Mycetoma in a non-endemic area: a diagnostic challenge

Background

Mycetoma is a chronic granulomatous infectious disease caused by filamentous bacteria or by fungi. The disease is endemic in certain tropical and subtropical areas of the world but can be found elsewhere posing sometimes a diagnostic challenge for clinicians.

Case presentation

A 65-year- old man presented with a right foot swelling evolving for 25 years. During that time, several diagnosis and treatments have been made without any improvement. The disease spread to bones, and misdiagnosed as Kaposi’s sarcoma. Transtibial amputation has been performed, and the histopathological examination revealed finally the diagnosis of eumycotic mycetoma. The patient recovered well after surgery and orthopedic prosthesis was prescribed for him.

Conclusion

Mycetoma in non endemic areas is usually misdiagnosed and mismanaged leading to unnecessary and inappropriate surgery. Health practitioners should be aware of that fact in order to provide an accurate management.

Predictors of Post-operative Mycetoma Recurrence Using Machine-Learning Algorithms: The Mycetoma Research Center Experience

Post-operative recurrence in mycetoma after adequate medical and surgical treatment is common and a serious problem. It has health, socio-economic and psychological detrimental effects on patients and families. It is with this in mind, we set out to determine the predictors of post-operative recurrence in mycetoma. The study included 1013 patients with Madurella mycetomatis causing eumycetoma who underwent surgical excision at the Mycetoma Research Centre, Khartoum, Sudan in the period 1991-2015. The clinical records of these patients were reviewed and relevant information was collected using a pre-designed data collection sheet. The study showed, 276 patients (27.2%) of the studied population developed post-operative recurrence, 217 were males (78.6%) and 59 were females (21.4%). Their age ranged between 5 to 70 years with a mean of 32 years. The disease duration at presentation ranged between 2 months and 17 years. The majority of the patients 118 (42.8%) had mycetoma of 1 year duration. In this study, students were the most affected; 105 (38%) followed by workers 70 (25.4%), then farmers 48(17.3%). The majority of the patients were from the Central Sudan 207 (75%), Western Sudan 53 (19.2%) while 11 patients (4%) were from the Northern part. Past history of surgical intervention performed elsewhere was reported in 196 patients (71.1%). Family history of mycetoma was reported in 50 patients (18.1%). The foot was the most affected site, 245 (88.7%), followed by the hand seen in 19 (6.8%) patients and 44 (4.5%) had different sites involvement. Most of the patients 258 (93.5%) had wide local surgical excisions while 18 had major amputation. The model predicted that the certain groups have a high risk of recurrence, and these include patients with disease duration greater than 10 years and extra-pedal mycetoma. Patients with disease duration between [5-10] years, with pedal mycetoma, who had previous surgery, with positive family history and underwent wide local surgical excision. Patients with disease duration [5-10] years, with pedal mycetoma, had previous surgery, with no family history but presented with a disease size (> 10 cm), were non- farmers and underwent wide local surgical excision. Other groups are patients with disease duration (≤5 years), with pedal mycetoma, age <59 years, living in the Western /Eastern / Southern regions of the Sudan and with positive family history and had wide local surgical excision. Also included patients with disease duration (≤5 years), with pedal mycetoma, aged <59 years, living in the northern or central region, with no family history but presented with a disease size >10 cm, working as farmers or students and underwent wide local surgical excision. In conclusion, these groups of patients need special care to reduce the incidence of post-operative recurrence with its morbidity and detrimental consequences. In depth studies for the other predisposing factors for post-operative recurrence such as genetic, immunological and environmental factors are needed.