Table 1 Clinical, radiological and microbiological differential features between eumycetoma and actinomycetoma
| Eumycetoma | Actinomycetoma | |
|---|---|---|
| Causative organism | =Fungi, mainly four Madurella mycetomatis (most common) Madurella grisea Pseudoallescheria boydii Leptosphaeria senegalensis Others … | =Bacteria, numerous Nocardia spp. (mostly in regions with higher humidity) Nocardia brasiliensis Nocardia asteroides Nocardia otidiscaviarum Actinomadura spp Actinomadura madurae Actinomadura pelletieri Streptomyces somaliensis Actinomyces israeli Others … |
| Clinical | Slow evolution Most often the foot Well-limited tumor with a clear margin White or black grains Rare lymphatic metastasis | Rapid evolution Most commonly the foot, but also the chest, head and abdomen Diffuse mass with no clear margin, more inflammatory and destructive Many grain colors, but not black Frequent lymphatic metastasis |
| MRI | Few but large well limited soft tissues cavities Less osteophilic | Numerous soft tissues cavities with a small size and unclear margins Rapid bone involvement |
| Direct microscopic examination of the grains | Black or white Diameter > 3 μm Few thick hyphae dilated in places to form vesicles No fringes Periodic-acid–Schiff stain Gomori methanamine silver stain | Red or white Diameter < 1 μm Thin and numerous grains, no hyphae Fringes in the outskirt Gram stain |
| Culture of the grains | Sabouraud - antibiotics culture media Slow growth 2–3 weeks | Sabourauld without antibiotics media Loewenstein culture media Rapid growth |