II. Definitions
-
Mycetoma (Maduramycosis)
- Chronic progressive subcutaneous, Granulomatous infection
- Caused by non-acid fast Bacteria (Actinomycetoma) and fungi (Eumycetoma)
- Subcutaneous Nodules, abscesses, fistulae and swelling, typically on legs, and may involve hands
- Complications include local disfiguring lesions, and if untreated, Osteomyelitis or ankylosis
- Rare, life threatening systemic spread to Pelvis, lungs, spinal cord
-
Actinomycetoma
- Chronic subcutaneous, Granulomatous lesions due to Actinomycetes, non-acid fast Bacteria
- Actinomycetes include soil-based Bacteria, Actinomadura, Nocardia, Streptomyces
-
Eumycetoma
- Chronic subcutaneous, Granulomatous lesions due to fungal infection
III. Causes: Nodular Lymphangitis
- Common Causes
- Sporotrichosis: Sporothrix schenckii (fungus)
- Classic prototype of 'sporotrichoid' infection
- Gardening, splinters or Animal Bites or scratches
- Nocardia brasiliensis (Nocardiosis)
- Gardening or splinter exposure
- Mycobacterium marinum
- Aquariums, fish handling or other water exposure
- Leishmania brasiliensis (Leishmaniasis)
- Limited to sandfly endemic areas
- Sporotrichosis: Sporothrix schenckii (fungus)
- Other Causes
IV. Findings: Nodular Lymphangitis
- Exposure to soil or water borne organisms
-
Granulomatous reaction up extremity lymph chain
- Nodular lesions
- Local tissue necrosis
- Abscess formation
- No systemic symptoms
V. Labs: Histology
-
Mycetoma
- Suppurative Granulomas
- Neutrophil infiltrates
- Palisaded histiocytes
-
Actinomycetoma
- Thin filaments (0.5 to 1 um) on Gram Stain or methenamine silver stain
-
Eumycetoma
- Thick fungal hyphae
VI. Differential Diagnosis
- See Subcutaneous Nodule (e.g. Rheumatoid Nodule)
- Cellulitis with ascending lymphangitis