Points to Ponder for NEET-PG, FMGE & NEXT
- Mycetoma is a chronic granulomatous infection presenting with swelling, sinuses, and diagnostic granules in the discharge.
- Mycetoma can be caused by fungi (eumycetoma) or bacteria (actinomycetoma).
- Actinomycetoma madurae as the most common cause of actinomycetoma, especially in India.
Definition: Mycetoma is a chronic, localized infection characterized by granulomatous inflammation of the subcutaneous tissues and deeper structures. It most commonly affects the foot but can involve the hand and other areas.
Clinical Presentation:
- Subcutaneous swelling
- Multiple draining sinuses
- Discharge of seropurulent fluid containing diagnostic granules (microcolonies of the causative organism)
Etiology: Mycetoma can be caused by either fungi (eumycetoma) or bacteria (actinomycetoma).
Eumycetoma (Fungal Mycetoma):
- Caused by subcutaneous fungal infection.
- Classified based on the color of the discharged granules:
- Black grain mycetoma: Caused by fungi like Madurella mycetomatis, Madurella grisea, Erophiala dermatitidis, or Allescheria boydii.
- White grain mycetoma: Caused by fungi like Pseudallescheria boydii, Aspergillus nidulans, Fusarium, or Acremonium.
Actinomycetoma (Bacterial Mycetoma):
- Caused by bacteria, most commonly Actinomycetoma madurae (especially in India). Other causative agents include Actinomyces, Nocardia, Streptomyces, and Allescheria boydii.
- Granules are typically white to yellow. However:
- Actinomadura pelletieri can produce red granules.
