249.1 🎓 醫孞生版

249.1.0.1 📌 䞀頁重點

249.1.0.1.1 Sporotrichosis (“Rose Gardener’s Disease”)
249.1.0.1.1.1 Pathogen
  • Sporothrix schenckii complex (S. brasiliensis, S. globosa, S. luriei)
  • Dimorphic fungus
  • Mold in environment (soil, plants, decaying wood, rose thorns, sphagnum moss)
  • Yeast in tissue
249.1.0.1.1.2 Transmission
  • Traumatic inoculation through skin (rose thorn, sphagnum moss, hay bales)
  • Zoonotic (cats — Brazil epidemic of cat-borne S. brasiliensis since 1998)
  • Rarely inhaled / disseminated
249.1.0.1.1.3 Geography
  • Worldwide, tropical + subtropical
  • Brazil epidemic ongoing (cat-borne S. brasiliensis)
  • USA + Latin America + Japan + Africa + Asia
  • Outdoor workers, gardeners, florists
249.1.0.1.1.4 Clinical Forms
249.1.0.1.1.5 Lymphocutaneous (Most Common)
  • 1-12 weeks post-inoculation
  • Papulonodular lesion at inoculation site (often pruritic, may ulcerate)
  • Lymphatic spread in chain along nodes (proximal to lesion)
  • “Sporotrichoid pattern” — multiple nodules in lymphatic chain
  • Often painless
  • Months without treatment
249.1.0.1.1.6 Fixed Cutaneous
  • Single non-lymphatic lesion
  • More chronic course
249.1.0.1.1.7 Pulmonary (Rare; Inhalation)
  • COPD + immunocompromise
  • Mimics TB
249.1.0.1.1.8 Disseminated (Rare)
  • HIV + immunocompromise
  • Skin + joints + bone + CNS
249.1.0.1.1.9 Osteoarticular
  • Joint involvement
  • Sometimes from disseminated
249.1.0.1.1.10 Diagnosis
  • Culture of biopsy / aspirate (mold + yeast forms)
  • Histology: oval / cigar-shaped yeast (less reliable than culture)
  • Asteroid body (Splendore-Hoeppli reaction)
249.1.0.1.1.11 Treatment
  • Itraconazole 200 mg PO bid × 3-6 months — preferred for cutaneous
  • Potassium iodide (SSKI) — historic, cheap; tropical settings
  • Liposomal AmB → itraconazole for severe / disseminated / pregnant
  • Treat for 2-4 weeks beyond clinical resolution
249.1.0.1.2 Chromoblastomycosis
249.1.0.1.2.1 Pathogen
  • Dematiaceous (pigmented, black) fungi: Fonsecaea pedrosoi, Cladophialophora carrionii, Phialophora verrucosa, Rhinocladiella aquaspersa
  • “Black fungi” in tissue
249.1.0.1.2.2 Geography
  • Tropical + subtropical (Latin America, Africa, Asia, parts of Australia)
  • Brazil, Madagascar, Cuba, Mexico, Venezuela, Cameroon
249.1.0.1.2.3 Transmission
  • Traumatic inoculation through skin (thorn, splinter, soil exposure)
  • Agricultural workers + barefoot rural
249.1.0.1.2.4 Clinical
  • Chronic slow-growing skin lesion (often years-decades)
  • Lower extremities + arms
  • Papules → nodules → verrucous (cauliflower-like) plaques + ulcers + scarring
  • Often single limb / area
  • Lymphatic + hematogenous spread rare (mostly localized)
249.1.0.1.2.5 Diagnosis
  • Histology: “sclerotic bodies / Medlar bodies / muriform cells” — round brown thick-walled cells in tissue (pathognomonic)
  • KOH preparation of skin scraping
  • Culture (slow growth of dematiaceous mold)
249.1.0.1.2.6 Treatment
  • Itraconazole + terbinafine combination × months-years
  • Cryotherapy + thermotherapy adjunctive
  • Surgical excision for small lesions
  • Difficult to cure; long-term suppression often
249.1.0.1.3 Mycetoma
249.1.0.1.3.1 Background
  • Chronic granulomatous infection of skin + subcutaneous tissue → bone + tissue invasion
  • Triad: tumor + sinus tracts + granules
  • “Madura foot” (after Madurai, India)
249.1.0.1.3.2 2 Categories
249.1.0.1.3.3 Eumycetoma (True Fungi)
  • Madurella mycetomatis (most common)
  • Madurella grisea
  • Scedosporium boydii (Pseudallescheria)
  • Curvularia, Acremonium, Fusarium (others)
  • Black grains typically
249.1.0.1.3.4 Actinomycetoma (Filamentous Bacteria)
  • Nocardia brasiliensis (most common, Latin America)
  • Actinomadura madurae
  • Streptomyces somaliensis (Africa)
  • White, yellow, or red grains
249.1.0.1.3.5 Geography
  • Tropical “Mycetoma belt”: Sudan, Senegal, India (Madurai), Mexico, Venezuela
  • WHO neglected tropical disease
249.1.0.1.3.6 Clinical
  • Years of slow progression
  • Painless initially (foot most common)
  • Progressive tumor + sinus tracts + grains
  • Grain colors helpful diagnostic clue (eumycetoma vs actinomycetoma)
  • Bone invasion + osteomyelitis
  • Functional impairment
249.1.0.1.3.7 Diagnosis
  • Grains examined microscopically + cultured
  • Sclerotia (grains) color + texture
  • PCR identification
  • Imaging (X-ray, MRI for bone)
  • Biopsy histology
249.1.0.1.3.8 Treatment
249.1.0.1.3.9 Eumycetoma
  • Itraconazole 400 mg/d × months-years
  • Surgical resection often required
  • Combination (itraconazole + terbinafine + posaconazole) some cases
249.1.0.1.3.10 Actinomycetoma
  • TMP-SMX + dapsone or rifampin × months-years
  • More responsive to antimicrobial than eumycetoma
  • WHO MDA programs in some endemic regions