Chromoblastomycosis: Difference between revisions

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* Chronic cutaneous fungal implantation infection
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== Background ==
 
== Background ==
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=== Microbiology ===
* Causative fungi
 
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* Mostly members of the family ''Herpotrichiellaceae'' within the order ''Chaetothyriales''
** ''[[Fonsecaea pedrosoi]]'' (most common): present in Brazil, Mexico, Sri Lanka, Japan, and Madagascar
 
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* [[Is caused by::Fonsecaea species]]
** ''[[Cladosporium carrionii]]''
 
 
** ''[[Is caused by::Fonsecaea pedrosoi]]'' (most common), which is present in Brazil, Mexico, Sri Lanka, Japan, and Madagascar
** ''[[Phialophora verrucosa]]''
 
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** [[Is caused by::Fonsecaea monophora|''F. monophora'']] and [[Is caused by::Fonsecaea pugnacius|''F. pugnacius'']], which both have neurotropism
** ''[[Rhinocladiella aquaspersa]]''
 
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** [[Is caused by::Fonsecaea nubica|''F. nubica'']]
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* [[Is caused by::Cladophialophora species]]
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** ''[[Is caused by::Cladophialophora carrionii]]''
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** ''[[Is caused by::Cladophialophora samoensis]]''
 
* ''[[Is caused by::Cladosporium carrionii]]''
 
* ''[[Is caused by::Phialophora verrucosa]]''
 
* ''[[Is caused by::Rhinocladiella aquaspersa]]''
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* [[Is caused by::Exophiala species]], which is a black yeast-like mold
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** [[Is caused by::Exophiala dermatitidis]]
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=== History ===
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* Known by many names worldwide, including chapa (Cuba), figueira or formigueiro (Brazil), sundo or sustra (South America), foratra, gajo-miala, or didra (Madagascar)
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* Other medical names include black or yellow blastomycosis
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=== Pathophysiology ===
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* Characterized by a non-protective TH2 cell response
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=== Risk Factors ===
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* Agriculture work
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* Adult males (thought to be a protective effect of progesterone)
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=== Epidemiology ===
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* More common in tropics and subtropics worldwide
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* In the US, [[Is caused by::Fonsecaea pedrosoi]], [[Is caused by::Fonsecaea monphora]], and [[Is caused by::Phialophora verrucosa]]
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* Higher rates in Mexico, Brazil, other parts of northern South America, Madagascar, and China
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* Relatively high rate in Japan, as well
   
 
== Clinical Presentation ==
 
== Clinical Presentation ==
 
* Chronic localized fungal infection of the skin and subcutaneous tissue that produces raised, scaly lesions, usually in the lower extremities
 
* Chronic localized fungal infection of the skin and subcutaneous tissue that produces raised, scaly lesions, usually in the lower extremities
* Lesions are warty, cauliflower-like, pathognomonic '''muriform cells''' (copper penny) found on histology
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** Lesions are warty, cauliflower-like
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** Does not usually involve deeper structures like muscle or bone
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* Typically an implantation infection secondary to traumatic inoculation
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** Plants: wood, straw, grass, thorns, palm trees, bamboo, coconut shells, cacti
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** Animals: insect stings, cow stomp, buck rear, cock spine, caterpillars, leeches
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** Farming tools: hoes, axes, knives, and mills
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** May be associated with natural disasters (hurricanes and flooding), motor vehicle collisions, bricks, and shoes
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* '''Severity''' based on
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== Differential Diagnosis ==
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* Fungi
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** Other implantation mycoses: [[sporotrichosis]], [[eumycetoma]], and [[lacaziosis]]
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** [[Dimorphic fungi]]
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* Bacteria
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** Cutaneous [[non-tuberculous mycobacteria]]
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** [[Leprosy]]
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** [[Nocardiosis]]
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** [[Actinomycosis]]
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** [[Yaws]]
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** Tertiary [[syphilis]]
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* Parasites
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** [[Leishmaniasis]]
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** [[Rhinosporidioisis]]
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* Viruses: [[Human papilloma virus]]
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* Non-infectious causes
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** Squamous cell carcinoma
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** Mycosis fungoides (cutaneous T-cell lymphoma)
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** Sarcoidosis
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** Systemic lupus serythematosus
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== Diagnosis ==
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* Skin scrapings or skin biopsy followed by histology and culture
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** Try to get areas where there are black specks ("cayenne pepper")
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* Histology
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** Pathognomonic '''muriform cells''' (copper penny cells)
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* Culture
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** Resistant to cycloheximide
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** May take up to 6 weeks to grow
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== Management ==
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* Surgical excision is the main therapy
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* Can also treat with cryotherapy, laster therapy, or heat therapy
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* Antifungals include [[Is treated by::itraconazole]], [[Is treated by::posaconazole]], [[Is treated by::isavuconazole]], and [[Is treated by::terbinafine]]
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** [[Fonsecaea species]] are relatively difficult to treat
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== Further Reading ==
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* Chromoblastomycosis. ''Clin Microbiol Rev''. 2017;30(1):233–276. doi: [https://dx.doi.org/10.1128/CMR.00032-16 10.1128/CMR.00032-16]
   
 
[[Category:Fungal infections]]
 
[[Category:Fungal infections]]

Revision as of 12:11, 3 November 2019

  • Chronic cutaneous fungal implantation infection

Background

Microbiology

History

  • Known by many names worldwide, including chapa (Cuba), figueira or formigueiro (Brazil), sundo or sustra (South America), foratra, gajo-miala, or didra (Madagascar)
  • Other medical names include black or yellow blastomycosis

Pathophysiology

  • Characterized by a non-protective TH2 cell response

Risk Factors

  • Agriculture work
  • Adult males (thought to be a protective effect of progesterone)

Epidemiology

Clinical Presentation

  • Chronic localized fungal infection of the skin and subcutaneous tissue that produces raised, scaly lesions, usually in the lower extremities
    • Lesions are warty, cauliflower-like
    • Does not usually involve deeper structures like muscle or bone
  • Typically an implantation infection secondary to traumatic inoculation
    • Plants: wood, straw, grass, thorns, palm trees, bamboo, coconut shells, cacti
    • Animals: insect stings, cow stomp, buck rear, cock spine, caterpillars, leeches
    • Farming tools: hoes, axes, knives, and mills
    • May be associated with natural disasters (hurricanes and flooding), motor vehicle collisions, bricks, and shoes
  • Severity based on

Differential Diagnosis

Diagnosis

  • Skin scrapings or skin biopsy followed by histology and culture
    • Try to get areas where there are black specks ("cayenne pepper")
  • Histology
    • Pathognomonic muriform cells (copper penny cells)
  • Culture
    • Resistant to cycloheximide
    • May take up to 6 weeks to grow

Management

Further Reading