Advanced Eumycetoma of the Right Foot Resulting in Below-Knee Amputation in Somalia: A Case Report

Abstract

Introduction

Mycetoma is a chronic, progressively destructive neglected tropical disease that presents with localised swelling, multiple sinus tracts and a discharge containing grains, and that may extend into deep tissue and bone. Somalia lies within the recognised mycetoma belt, but the national burden is poorly documented, and few patients reach specialist care early enough for the limb to be saved.

Case Presentation

A 33-year-old man from Qoryooley District, Lower Shabelle, Somalia, presented with a seven-year history of progressive swelling of the right foot. Examination showed massive tumefaction and multiple discharging sinuses containing black grains. Magnetic resonance imaging demonstrated extensive soft-tissue destruction, sinus tracts, tendon involvement and osteomyelitis of several tarsal and metatarsal bones. Histopathological examination confirmed eumycetoma. Specialised fungal culture and molecular testing were not available at the institution, so the causative species could not be identified. Because the extent of soft-tissue destruction and multi-bone involvement left no viable limb-sparing option, a right below-knee amputation was performed, followed by oral itraconazole planned for twelve months. At three months the stump had healed with no clinical evidence of recurrence, and the patient continued antifungal treatment and rehabilitation.

Conclusion

Delayed diagnosis of eumycetoma can cost the patient a limb. Magnetic resonance imaging determined management here by mapping the extent of disease and showing that limb-sparing surgery was no longer feasible. Earlier referral, and better access to imaging, mycological diagnosis and antifungal treatment, would spare other patients in Somalia the same outcome.

Introduction

The World Health Organization classifies mycetoma as a neglected tropical disease. It is a chronic granulomatous infection of subcutaneous tissue that produces tumorous swelling, sinus tracts and a discharge containing grains, and may be caused either by filamentous bacteria (actinomycetoma) or by fungi (eumycetoma).^1–3 Organisms probably enter through minor penetrating injury such as a thorn prick, then form compact colonies known as grains, around which a granulomatous reaction develops.^1,2 The distinction between the two forms matters clinically, because actinomycetoma usually responds to prolonged combination antibacterial therapy whereas eumycetoma requires long-term antifungal treatment, generally combined with surgery.^1,4

The disease is concentrated in the mycetoma belt, which stretches roughly between 15° south and 30° north of the equator.^2,5 Somalia lies in the eastern part of this belt and is listed by the World Health Organization among endemic countries, alongside Sudan, Ethiopia and Yemen.^3,5 What is known of the Somali burden, however, rests on a thin literature. A recent review identified only 11 publications on mycetoma in Somalia since 1927, comprising six case reports covering 12 patients and three case series covering 163 patients, a total of 175 reported cases.⁶ A hospital series from Mogadishu subsequently described 50 patients, of whom 76% were male and 44% were farmers, with the lower limb affected in 80%.⁷ An earlier series from the same city reported 10 patients.⁸ Individual Somali reports document eumycetoma of the foot, wrist and gluteal region, actinomycetoma of the neck, and one species-confirmed case caused by Biatriospora mackinnonii (Table 1).^9–13 Mycetoma is not a notifiable disease in Somalia, and the true number of cases is certainly higher than these figures suggest.⁶ Neighbouring Sudan, by contrast, has reported several thousand patients from a single referral centre and has generated most of the clinical evidence base.^14,15

Table 1.

Published Reports of Mycetoma from Somalia, with the Present Case for Comparison

Patients	Type and Site	Management	Outcome	Report Reference
175 in 11 publications since 1927	Both types, sites not aggregated	Not aggregated	Concluded that reported cases substantially understate the true burden	[6]
10	Both types, lower limb predominant	Surgery with antibacterial or antifungal therapy	Not reported in detail	[8]
50	Both types, lower limb in 80%	Varied	Diagnostic and follow-up difficulties described	[7]
1	Eumycetoma caused by Biatriospora mackinnonii	Not available in the indexed record	Not available in the indexed record	[9]
1	Actinomycetoma of the neck	Co-trimoxazole and amikacin	Marked improvement at three months	[10]
1	Eumycetoma of the gluteal region, 10-year history	Surgical excision with antifungal therapy	Marked improvement	[11]
1	Eumycetoma of the wrist, 3-year history	En bloc surgical excision	Curative, limb preserved	[12]
1	Eumycetoma of the right calcaneus, 4-year history	Wide debridement with adjuvant itraconazole	Limb preserved	[13]
1	Eumycetoma of the right foot and ankle, 7-year history	Right below-knee amputation with itraconazole	Stump healed at three months, limb lost	Present case

Untreated lesions enlarge and invade deep tissue and bone. Late presentation after ineffective treatment can therefore end in extensive bone destruction, disability and amputation.^1,14,16 We describe a Somali patient whose eumycetoma had reached that stage before he was seen at a specialist centre.

Case Presentation

A 33-year-old man from Qoryooley District, Lower Shabelle, southern Somalia, attended the outpatient clinic of Mogadishu Somali Türkiye Recep Tayyip Erdogan Training and Research Hospital with a seven-year history of an enlarging mass of the right foot. The course of the illness is set out in Figure 1.

Figure 1.

Schematic timeline of disease progression, from a painless subcutaneous nodule to below-knee amputation and the three-month outcome. Boxes above and below the axis mark successive clinical stages. The interval from onset to definitive surgery was seven years.

The lesion began as a small painless nodule and expanded slowly into a diffuse swelling of the whole foot. For more than a year before presentation, multiple sinuses had been discharging black grains. He recalled no penetrating injury. Over those seven years he attended several hospitals and received repeated courses of antimicrobial treatment without benefit. No records of that treatment were available, so the agents, doses and durations could not be established, and it is not known whether any antifungal drug was ever given. Walking had become progressively difficult. He had no comorbidity and no known allergy.

On examination the right foot and ankle were grossly swollen and deformed (Figure 2), with multiple actively discharging sinuses over the ankle and metatarsal region. The discharge was purulent and contained visible black grains, and the surrounding skin was thickened and hyperpigmented. Distal neurovascular status was intact, but the foot had lost all useful function. The triad of tumefaction, sinuses and grains indicated mycetoma, and the black colour of the grains favoured a fungal cause. Actinomycetoma was the principal alternative. Chronic bacterial osteomyelitis, skeletal tuberculosis, botryomycosis, nocardiosis and soft-tissue malignancy were also considered, since each can produce a chronic destructive mass of the foot.¹⁷

Figure 2.

Clinical appearance of the right foot and ankle at presentation. Labels identify diffuse tumefaction, hyperpigmented and thickened skin over the swelling, and gross deformity of the foot contour.

Magnetic resonance imaging (MRI) of the right foot and ankle showed multiple heterogeneous lesions of the tarsal and metatarsal bones, with marrow oedema consistent with chronic osteomyelitis. Sinus tracts extended to the skin, and peritendinous collections contained nodular foci indicating tenosynovitis with intralesional grains (Figure 3). No compartment of the foot was spared. Laboratory testing showed an elevated C-reactive protein with a normal white cell count, normal renal and liver function, and negative screening for human immunodeficiency virus, hepatitis B virus and hepatitis C virus. The imaging, laboratory and pathological findings are given in full in Table 2.

Figure 3.

Sagittal magnetic resonance image of the right foot and ankle. Labels identify abnormal marrow signal in the hindfoot, extensive heterogeneous signal abnormality in the midfoot, and nodular hypointense foci consistent with intralesional grains. Imaging also demonstrated bone marrow oedema consistent with chronic osteomyelitis, sinus tracts extending to the overlying skin, and peritendinous fluid collections. No dot-in-circle sign was identified.

Table 2.

Imaging, Laboratory and Pathological Findings at Presentation

Investigation	Findings
Magnetic resonance imaging of the right foot and ankle	Multiple heterogeneous lesions of the tarsal and metatarsal bones, hypointense on T1- and T2-weighted images, with diffuse peripheral and internal contrast enhancement. Bone marrow oedema consistent with chronic osteomyelitis. Multiple sinus tracts extending to the overlying skin. Fluid collections adjacent to the flexor and extensor tendons containing nodular T2-hypointense foci, indicating tenosynovitis with intralesional grains. Diffuse soft-tissue oedema throughout the foot. No acute fracture and no dot-in-circle sign.
Inflammatory markers	Elevated C-reactive protein at 25 mg/L. Normal white cell count at 7.58 × 103/µL
Haematology	Haemoglobin 12.9 g/dL, red cell count 4.88 × 106/µL, platelets 336 × 103/µL
Renal and liver function	Within normal limits at baseline, before antifungal therapy
Viral screening	Negative for human immunodeficiency virus, hepatitis B virus and hepatitis C virus
Macroscopic pathology	Grey-brown tissue fragments measuring 3.5 × 2 × 2 cm with necrotic cut surfaces
Histopathological examination	Granulomatous inflammation with a chronic inflammatory infiltrate and black grains, diagnostic of eumycetoma
Special stains	Periodic acid-Schiff and Grocott methenamine silver confirmed the fungal nature of the grains
Fungal culture and molecular identification	Not performed and not available at the institution. Causative species not determined
Bacterial tissue culture	Coagulase-negative Staphylococcus epidermidis, susceptible to ciprofloxacin, linezolid and trimethoprim-sulfamethoxazole and resistant to penicillin G. Interpreted as colonisation or contamination

Note: T1 and T2 denote longitudinal and transverse relaxation time weighted sequences.

An excisional biopsy was performed. Haematoxylin and eosin sections showed granulomatous inflammation with a chronic inflammatory infiltrate and black grains diagnostic of eumycetoma (Figure 4). Periodic acid-Schiff and Grocott methenamine silver stains confirmed the fungal nature of the grains. Fungal culture and molecular identification were not available at the institution, so the causative species was not determined. Tissue culture grew coagulase-negative Staphylococcus epidermidis, susceptible to ciprofloxacin, linezolid and trimethoprim-sulfamethoxazole and resistant to penicillin G. With no systemic features of infection and a normal white cell count, the treating team judged this to represent colonisation or contamination rather than a clinically significant secondary infection, and no antibacterial treatment was given.

Figure 4.

Histopathological section of the excised tissue stained with haematoxylin and eosin. Labels identify a fungal grain, brown pigment within the grain, and the surrounding granulomatous and chronic inflammatory infiltrate.

Limb-sparing surgery was considered and rejected. Wide local excision is appropriate for localised disease with a definable margin, but here the infection occupied every compartment of the foot, involved several tarsal and metatarsal bones, and had produced sinus tracts running from skin to bone. No plane of clearance existed that would have left a functional, infection-free foot. Seven years of antimicrobial treatment had already failed. In mycetoma, amputation is reserved for advanced disease with massive bone involvement and severe secondary infection,¹⁷ and this patient met that description. A right below-knee amputation was therefore performed.

The procedure was carried out under spinal anaesthesia with the patient supine, with division at the distal third of the leg. The operative findings confirmed extensive chronic infection, with necrotic tissue, foul-smelling purulent discharge, sinus tracts reaching bone, and abundant black grains within deep tissue planes and bone (Figure 5). Haemostasis was secured, myoplasty was performed, a drain was inserted, and the fascia and skin were closed in layers.

Figure 5.

Intraoperative photograph of the amputated specimen following right below-knee amputation. Labels identify the amputated foot with gross tumefaction, transected bone, and divided muscle and soft tissue at the level of section.

Oral itraconazole 200 mg twice daily was started once the histopathological diagnosis was confirmed. This dose is the accepted standard for eumycetoma, and a total duration of twelve months was planned, in line with reported regimens and current guidance.^4,18,19 Response was assessed clinically at each visit by inspecting the stump for swelling, sinus formation, discharge or grains, and safety was monitored by serial renal and liver function tests. Postoperative care included analgesia and wound care, and the patient was referred to physiotherapy for stump management and prosthetic fitting.

Recovery was uncomplicated. The patient remained haemodynamically stable, the wound healed without complication, and the drain was removed according to protocol. He described relief once the chronically infected limb had been removed. At three months the stump had healed, with no swelling, sinus formation, discharge or grains. Renal and liver function remained normal, and he remained adherent to itraconazole while continuing physiotherapy and awaiting a prosthesis.

Discussion

Seven years separated a painless nodule from a below-knee amputation. That interval, rather than any unusual feature of the organism or the host, determined the outcome. Mycetoma is painless in its early stages, which is why patients delay, and in Somalia the delay is compounded by limited awareness, few referral pathways and restricted access to specialist diagnosis.^6,7 By the time he reached a centre able to image and biopsy the lesion, the foot could no longer be saved.

Among 6792 patients seen at the Mycetoma Research Centre in Khartoum between 1991 and 2014, 37% already had massive lesions when first seen. Of the 807 who underwent surgery, 248 or 30.7% developed postoperative recurrence, and 120 patients, 1.7% of the cohort, required amputation.¹⁴ Lesion size of 5 cm or more independently predicts reduced odds of cure.²⁰ Localised eumycetoma can often be managed with prolonged itraconazole and wide excision, and a preoperative course of itraconazole encapsulates and localises the lesion, which facilitates complete excision and helps to avoid mutilating surgery.¹⁸ Neither approach was applicable here, because the disease was neither localised nor amenable to encapsulation.

Two recently reported Somali patients kept the affected limb. A 25-year-old man with eumycetoma of the right calcaneus of four years’ duration, reported previously by our group, was treated with wide debridement and adjuvant itraconazole.¹³ A three-year wrist lesion in a Somali woman was cured by en bloc excision alone.¹² What separates them from the present patient is duration, compartmental spread and the number of bones involved, not the organism or the treatment available.

MRI defined the full extent of soft-tissue and osseous involvement and showed tenosynovitis with intralesional grains. The dot-in-circle sign, produced by grains surrounded by granulomatous tissue, is highly specific for mycetoma and can secure the diagnosis in less advanced disease,^21,22 and it was reported in the calcaneal case noted above.¹³ Its absence here is unsurprising once grains are dispersed through necrotic tissue. In advanced disease the value of MRI lies less in diagnosis than in mapping bone destruction, periosteal reaction and soft-tissue spread for operative planning,¹⁷ which is what established that limb-sparing surgery was not feasible.

Histopathological examination identifies Madurella mycetomatis correctly in 97.5% of confirmed cases, appreciably better than fine-needle aspiration cytology, which makes it a reasonable primary diagnostic method where mycological capacity is limited.²³ It cannot, however, substitute for species identification. Molecular methods identify the organism to species level and so guide treatment, but they are expensive, not field-friendly and largely unavailable in endemic areas.²⁴ A recent World Health Organization landscape analysis found the same pattern across low-income and middle-income countries, where most fungal diagnostic platforms are culture-dependent and infrastructure-intensive.²⁵

Limitations

The causative species was not identified, because neither fungal culture nor molecular testing was available. Madurella mycetomatis is the commonest causative agent worldwide and accounted for 70% of cases in neighbouring Sudan,^5,14 but its role here remains an inference. Records of the antimicrobial treatment given elsewhere over seven years could not be retrieved, so neither the agents used nor their duration is known, and previous antifungal exposure cannot be excluded. Follow-up extended to only three months, too short to assess recurrence. Recurrence after apparently successful treatment is well documented, and the Sudanese postoperative recurrence rate of 30.7% argues for surveillance measured in years rather than months.^14,18,20 Findings from a single patient cannot be generalised to the Somali mycetoma population.

Future Directions

Somalia has neither mycetoma surveillance nor a national registry. Making the disease notifiable and recording cases systematically would establish the true burden. Modest mycological capacity would identify the species involved and allow outcomes to be compared with those reported from Sudan and other endemic countries.^6,7

Conclusion

This patient lost a leg to a disease that had been treatable for most of its seven-year course. The lesion was painless early on, the treatment he received elsewhere was ineffective, and neither imaging nor mycological diagnosis was available to him until the foot had been destroyed. MRI then defined the extent of disease and established that no limb-sparing option remained, and histopathology supplied the diagnosis that culture could not. The practical lesson is not a new drug or technique but earlier recognition of the clinical triad and a referral route that leads to imaging and biopsy.

Funding Statement

The authors received no specific funding for this work.

Data Sharing Statement

All clinical information supporting this case report is contained within the article. Further de-identified information may be obtained from the corresponding author on reasonable request, subject to patient confidentiality and institutional requirements.

Ethical Considerations

The Ethics Committee of SIMAD University, Mogadishu, Somalia, approved this case report. The patient was diagnosed and treated at Mogadishu Somali Türkiye Recep Tayyip Erdogan Training and Research Hospital, Mogadishu, Somalia. Under the policy of that institution, separate institutional approval was not required for publication of a single de-identified case report, and publication is covered by the written informed consent given by the patient.

Consent for Publication

Written informed consent was obtained from the patient for publication of this case report and of all accompanying clinical, radiological, histopathological and intraoperative images.

Disclosure

The authors report no conflicts of interest in this work.