• sporotrichosis
• chromoblastomycosis
• mycetoma
• subcutaneous zygomycosis
• subcutaneous hyphomycosis
• lobomycosis 

Lymphocutaneous Sporotrichosis  

(Sporothrix schenckii)

Morphology and Epidemiology

• dimorphic fungus grows rapidly, wrinckled membrane surface that's tan, brown, or black
• narrow, hyaline, septate hyphae w/ oval conidia on conidiophores
• rarely see yeast spores in prep
• warm climates, get via traumatic inoculation
• zoonotic transmission via armadillo, infected cats 

Lymphocutaneous Sporotrichosis

(Sporothrix schenckii)

Clinical Presentation, Lab Diagnosis 

• chronic infection, 
• primary ulcerative lesion (pus)-->2wks later get secondary nodules: linear chain of painless subcutaneous nodules extending proximally along lymphatic drainage of primary lesion
• Dissemination to secondary sites = rare
• at 25C=mold; at 37C=yeast; grow on Sabouraud agar 
• culture pus or tissue 2-5 days for diagnosis 
• Splendore-Hoeppli around yeast (asteroid body) but not diagnostic 

Lymphocutaneous Sporotrichosis

(Sporothrix schenckii)

Host Response, Treatment

• host response: mixed suppurative and granulomatous Splendore-Hoeppli material surrounding fungus (asteroid body)
• Treat with oral potassium iodide in saturated solution, orally over 3-4wks
  • nausea, salivary gland enlargement
• Itraconazole = treatment of choice
• Fluconazole if pt can't tolerate others
• heat to treat 

Chromoblastomycosis 

(Cladophialophora carrionii, Fonsecaea compacta, F. pedrosoi, Phialophora verrucosa, Rhinocladiella, Exophiala spp.)

Morphology and Epidemiology

• dematiaceous (naturally pigmented) molds, septate
  • different mechanisms of sporulation made ID difficult
• in tissue: form muriform cells (sclerotic bodies, medlar bodies) that are chestnut brown due to melanin in cell walls
  • divide by internal septation, appear as vertical and horizontal lines
  • medlar bodies = pigmented, bilaterally dividing, rounded, sclerotic cells
• often find in macrophages or giant cells
• Exophiala can produce conidia bearing annelids
• rural reas of tropics if lack protective footwear (direct innoculation of soil)
• Madagascar Fonsecaea pedrosi in areas of high rainfall
• Madagascar F. pedrosoi is main cause; lesion in lower extremities
• Australia C. carrionii lesions w/ upper limbs esp in hands 

Chromoblastomycosis

Clinical Presentation, Lab Diagnostics

• large, spherical, thick-walled, brown muriform cells (sclerotic bodies w/ septations along 1 or 2 planes); pigmented hyphae 
• infxn: chronic, pruritic, progressive, indolent, resistant to treatment
• early lesions are small and warty papules that enlarge slowly
• cauliflower-like growths clustered in satellite lesions; secondary to inoculation 
• ulceration and cyst formation, large lesions are hyperkeratotic, limb distorted b/c of fibrosis and secondary lymphadema
• secondary bacterial infection-->regional lymphadenitis, lymph stasis, elephantiasis
• Must isolate in culture to confirm diagnosis 
• Medlar

Chromoblastomycosis 

Characteristic host reponse, Treatment and interventions

• mixed suppurative and granulomatous
• pseudoepitheliomatous hyperplasia 
• Try to shrink larger lesions w/ heat, cryotherapy before using antifungals
• Itraconazole and terbinafine
• posaconazole w/ some success
• combine agents with flucytosine
• risk of recurrences w/in scar; no surgery 
• may get squamous cell carcinoma in long-standing lesions 

Eumycotic Mycetoma

(Phaeoacremonium spp., fusarium spp., aspergillus nidulans, seedosporium apiospermum, madurella spp., exophiala jeanselmei)

Morphology and Epidemiology

• caused by true fungi as opposed to actinomycotic mycetomas
• tropical areas w/ low rainfall
• Africa, india, brazil, venezuela, middle east
• infection via traumatic percutaneous implantation into exposed body part; foot and hand most common 
• men > women
• causative fungi differ by country 
• not contagious  

Eumycotic Mycetoma

Clinical Presentation, Lab Diagnosis

• localized, chronic, granulomatous, involve cutaneous and subcutaneous tissues
• multiple granulomas with aggregates of fungal hyphae (granules=grains)
  • granules/grains=many variations of internal and external structures such as: 
    • reduplications of cell wall to formation of a hard, cement-like ECM 
• granules composed of broad, (2-6mm) hyaline (pale granules) or dematiaceous (black granules), septate hyphae branching and forming chlamydoconidia 
• longstanding infxn; early lesions painless and increase in size until are disfigured by chronic inflammation and fibrosis
• sinus tracts appear on skin surface, drain serosanguineous fluid containing visible granules
• infection breaches tissue planes, destroys muscle and bone locally--> secondary spread is rare
• diagnosis based on grains or granules 

Eumycotic Mycetoma

Host Response, Treatment and Intervention

• abscesses drain externally via sinuses; deforming process w/ destruction of muscle, fascia, bone
• suppurative with multiple abscesses, fibrosis, sinus tracts
• Splendore-Hoeppli material at periphery of granule
• Treatments usually unsuccessful
• Local excision ineffective so amputation = only definitive treatment
• must differentiate from actinomycotic mycetoma as treatment usually helps actinomycotic mycetoma 

Subcutaneous Zygomycosis

(Basidiobolus ranarum, conidiobolus coronatus)

Morphology and Epidemiology

• sparese hyphal fragments = thin-walled, poorly stained surrounded by eosinophilis Splendor-Hoeppli material 
  • infrequent septae
  • hyphae not angio-invasive 
• saprophytes in leaf and plant debris; B. ranarum in intestinal contents of small reptiles, amphibians 
• B. ranarum after tarumatic implantation into subq tissues of thigh, buttocks, trunck
  • mainly in kids; 3:1 boys:girls; in middle-east
• C. coronatus following inhalation of spores-->invade tissues of nasal cavity
  • 10:1 male:female; in young adults; rare in kids 
  • in latin america, africa, india

Subcutaneous Zygomycosis

Clinical presentation and Lab Diagnosis

• broad hyphal fragments surrounded by splendore-hoeppli material
• B. ranarum: large, disk-shaped, rubbery, movable masses of shoulder, pelvis, hips; masses may expand locally and ulcerate; rare to disseminate
• C. coronatus: confined to rhinofacial area; firm and painless swelling of upper lip or face-->may get to orbig
  • no angioinvasion so no intracranial extension 
• need biopsy for diagnosis
  • see focal clusters of inflammation w/ eosinophils and typical zygomycotic hyphae surrounded by eosinophilic splendore-hoeppli

Subcutaneous Zygomycosis

Host response, Treatments, 

• Eosinophilic abscesses and granulation tissue with splendore-hoeppli material around fragmented hyphae 
• Treat with itraconazole, oral potassium iodide in saturated solution
• May need facial reconstructive surgery with C. coronatus
• may have extensive fibrosis even after eradicate fungus 

Subcutaneous Phaeohyphomycosis 

(exophiala jeanselmei, wangiella dermatitidis, bipolaris spp., alternaria spp., chaetomium spp., curvularia, phialophora)

Morphology and Epidemiology 

• brown hyphae 2-6mm, branched or unbranched, constricted at prominent septations
• yeast forms; chlamydoconidia may be present 
• grow as black molds in culture and appear as dark-walled, irregular, hyphal and yeastlike forms in tissue 
• Fontana-Masson melanin stain to confirm dematiaceous nature 
• in soil and plant debris; infect from traumatic infection (splinter)
• don't know why some organisms make phaeohyphomycotic cysts and other develop into mycetomas 

Subcutaneous Phaeohyphomycosis 

Clinical Presentation and Lab Diagnosis

• SubQ presents as solitary inflammatory cyst on feet, legs
• lesions grow slowly, expand over years; firm or fluctuant, painless 
• Dx via surgical excision of cyst
• Fontana-Masson melanin stain reveals inflammatory cyst w/ fibrous capsule, granulomatous rxn, and central necrosis
• individual and clustered dematiaceous fungal elements seen w/in giant cells and extracellularly near necrotic debris
• pigmentation seen on H&E
• grown in culture, identified by pattern of sporulation 

Subcutaneous Phaeohyphomycosis 

Host Response, Treatments

• SubQ cystic or solid granulomas
• overlying epidermis rarely affected
• surgical excision= treatment
• plaque-like lesions harder to excise so use itraconazole w/ or w/out concomitant flucytosine

Lacaziosis

(Lacazia laboi: an ascomycete fungus)

Morphology and Epidemiology

• spherical to oval and yeastlike in appearance
• usually intracellular 
• double-refractile cell wall
• sequential budding to reproduce; forms chains of cells connected by narrow, tubelike bridges 
• S and Central American tropics (humans, dolphins)
• Saprophyte of soil and vegetation (amazon rain forest)
• Cutaneous trauma=mode of transmission 
• evidence of dolphin-to-human transmission but no human-to-human
• mostly men (farmers, miners, hunters) 

Lacaziosis

Clinical Presentation and Lab Diagnosis

• NEVER cultured in vitro 
• slow developing cutaneous nodules (40-50 years) 
• lesions vary & may include: macules, papules, keloidal nodules (common), plaques, verrocous and ulcerated lesions 
• local spread via autoinoculation; see in traumatized areas)
• may have pruritus & hypersthesia or anesthesia w/ no symmetric manifestation 
• Dx based on yeast cells in lesion exudates or tissue sections 
• macrophages and giant cells seen may contain phagocytosed fungi

Lacaziosis

Treatments and Interventions

• surgical excision
• if widespread, will usually recur when treated surgically and may not respond to antifungals like clofazimine