Lesson 3.2

Cards (18)

  • fungal infections of the deeper tissues which includes but not limited to the dermis, subcutaneous fat and muscles.
    Subcutaneous mycoses
  • -They invade deeper into tissues, trigger inflammatory or immunologic reactions.
    -generally caused by a single specie or small group of fungi.
    Subcutaneous mycoses
  • -transmitted through skin trauma/prick: farming, gardening, forest work, mining
    -environmental pathogens
    -from soil, water, vegetable or organic matter
    -produces granules which are collected from biopsy (stain: H&E/PAS)

    *Characteristics of Dermatophytoses
    • Etiologic Agent: Sporothrix schenckii
    • present in soil, vegetable/organic matter
    • nodular and ulcerative lesions along lymphatics that drain the primary site of inoculation (cord-like w/ multiple draining sinus tracts)
    • dissemination to other sites is rare (<1%)
    • on direct detection, they may appear as cigar-shaped yeasts (smear) and manifest Splendore-Hoeppli phenomenon (biopsy)

    Sporothrichosis/Rose Gardener's Disease
  • rosette/ flowerette conidia
    Culture for Sporotrichosis
    • Etiologic Agent: Rhinosporidiosis
    • Polyploidy masses in nose/pharynx
    • seen in water
    • (*)Tissue: sporangium-sac-like structure filled with endospores
    Rhinosporidiosis
    • Etiologic Agent: Loboa loboi
    • Keloid-like subcutaneous nodule involving the extremities
    • Tissue: multiple budding cells in chain/ "string of beads"
    • does NOT grow in culture
    Lobomycosis
    • aka verrucous dermatitis or chromomycosis
    • chronic, pruritic, progressive, indolent infection that is resistant to treatment
    • exhibits verrucous nodules progressing to multiple, large, warty, "cauliflower-like" lesions in long term
    • complications: fibrosis, secondary lymphedema, secondary bacterial infection
    Chromoblastomycosis
  • brown sclerotic/copper/medlar/fission bodies AKA musiform cells

    Direct Exam of Biopsy in Chromoblastomycosis reveals
    • dematiaceous fungi
    • Fonsecaea pedrosoi
    • Phialophora verrucosa
    • Cladosporium carrionii
    • Exophiala spp
    • Cladophialophora spp
    • Rhinocladiella spp

    Agents in Chromoblastomycosis
  • short chain (acrotheca) - most common cause

    Fonsecaea pedrosoi
  • vase/flask-shaped

    Phialophora verrucosa
  • long chain (shield cell)

    Cladosporium carrionii
  • granulomatous lesions on foot with granules containing mycelial masses, sinuses with grains ("sulfur granules")

    Eumycotic Mycetoma/Madura foot/Madura mycosis
    • Pseudallescheria boydii - common cause (US)
    • Madurella spp
    • Leptosphaeria spp
    • Phaeoacremonium spp
    • Curvularia spp
    • Fusarium spp
    • Exophiala spp
    • Scedosporium spp
    Etiologic agents of Eumycotic Mycetoma
    • Nocardia spp - modified acid-fast
    • Actinomyces spp - sulfur granules

    Etologic Agents of Actinomycotic Mycetoma
    • usually painless solitary inflammatory cyst on legs, feet, and hands
    • grows slowly and may be firm or fluctant
    Subcutaneous Phaeohyphomycosis
    • Alternaria spp
    • Bipolaris spp
    • Curvularia spp
    • Phaeoacremonium spp
    • Exophiala jeanselmei
    Etiologic Agents of Subcutaneous Phaeaohyphomycosis