Mycetoma (Madura Foot)

Mycetoma, also known as Madura Foot, is a chronic, progressive infection of the skin, subcutaneous tissue, and sometimes bone.

• It is caused either by bacteria (Actinomycetoma) or fungi (Eumycetoma).

• The disease often develops slowly over months to years, leading to disfiguring lesions if untreated.

• Commonly affected populations include farmers, barefoot laborers, or individuals in rural, tropical, and subtropical regions.

• The most frequent site of involvement is the foot, but other areas such as legs, arms, buttocks, scalp, and trunk can also be affected.

• Early recognition is crucial to prevent permanent deformity, disability, and secondary infections.

Etiology:

• Actinomycetoma: caused by filamentous bacteria such as Nocardia, Streptomyces, or Actinomadura species

• Eumycetoma: caused by fungi such as Madurella mycetomatis, Fusarium, or Acremonium species

Signs & Symptoms

• Initial lesion: Small, painless nodule at the site of inoculation

• Progression: Nodules enlarge slowly over months to years

• Characteristic discharging sinuses:

  • Sinuses drain grains (microcolonies)

  • Actinomycetoma: white, yellow, or pale grains

  • Eumycetoma: black grains

• Pain: Often mild initially; may precede rupture of sinuses

• Swelling and deformity: Chronic disease may lead to fibrosis, lymphedema, or bone involvement

• Common localization:

  • Foot (most common) – plantar, dorsum, or toes

  • Legs, arms, buttocks, scalp, trunk

Complications:

• Secondary bacterial infections

• Osteomyelitis in long-standing disease

• Functional impairment due to deformity

Diagnostic Criteria

Clinical features consistent with Mycetoma:

• Slow-growing subcutaneous nodules

• Multiple sinuses with visible grains

• Typical locations: foot, legs, arms, buttocks, scalp, trunk

• Pain preceding sinus discharge

• Chronic course over months to years

Differentiation of type:

• Actinomycetoma: pale white/yellow grains; often responds well to antibiotics

• Eumycetoma: black grains; often requires prolonged antifungal therapy ± surgery

Investigation

• Microscopic examination of grains (Gram stain, KOH mount)

• Culture for bacterial or fungal identification

• Histopathology of biopsy if diagnosis unclear

• Imaging:

  • X-ray: detect bone involvement

  • Ultrasound/MRI: assess soft tissue and sinus tracts

• Blood tests if prolonged antimicrobial therapy is planned (especially for co-trimoxazole)

Treatment

Non-Pharmacological Treatment

• Surgical intervention: Excision or debridement may be indicated for localized lesions

• Protective measures: Footwear and protective clothing in at-risk populations, e.g., farmers or those in contact with contaminated soil or cattle dung

• Patient education: Emphasize early treatment to prevent deformity

Pharmacological Treatment

Actinomycetoma (Bacterial form)

Combination therapy:

• Co-trimoxazole (PO) 480–960 mg every 12 hours for 5 weeks

AND

• Amikacin 7.5 mg/kg every 12 hours for 5 weeks

Alternatively:

• Co-trimoxazole (PO) 480–960 mg every 12 hours for 5 weeks

AND

• Dapsone (PO):

  • Adults: 100 mg once daily for 2–4 months

  • Paediatric: 25–50 mg once daily for 5 weeks

Monitoring:

• Regular blood tests (CBC, liver function) if co-trimoxazole or dapsone therapy exceeds 14 days.

Eumycetoma (Fungal form)

Non-Pharmacological Treatment

• Surgery where indicated.

• Footwear and protective clothing in at-risk populations (e.g. cattle herders).

Pharmacological Treatment

• Itraconazole (PO) 200 mg every 12 hours for 5 weeks or longer (up to 1 year).

Referral to surgeon

• Radical surgery for selected cases.

Adjunct therapy:

• Analgesics for pain control.

• Management of secondary bacterial infections if present.

Prevention

• Avoid barefoot walking in endemic areas

• Use protective footwear and gloves when handling soil or animals

• Early recognition and treatment of minor skin injuries

• Community health education on risks and hygiene