Clinical Classification by 5gi202gp

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									       Clinical Classification
• Systemic (deep seated) mycoses
  – Blastomycosis
  – Coccidiomycosis
  – Cryptococcosis
  – Histoplasmosis
  – Paracoccidiomycosis
  – Sporotrichosis (rarely systemic usually
    subcutaneous)
         Clinical classification:
             subcutaneous
•   See table 19-3, pg 986
•   Relatively low virulence
•   Access gained via traumatic implantation
•   3 groups - next page
•   Subcutaneous:
      dermis connective tissue? lymphatics?
    Clinical Classification: subcut
Mycetoma (maduromycosis): tissue form is a
 “grain” (microcolony of hyphae),
 environmental form is a mould – not
 dimorphic
Chromoblastomycosis (Chromomycosis)
   a)chromo = pigmented
   b)tissue form is a “sclerotic body” = hard
   environmental form is a mould = dimorphic
Sporotrichosis : single species. Dimorphic:
 tissue form is a yeast, environmental form is
 a mould
          Clinical Classification:
•                  cutaneous
  Lots of overlap here: cutaneous vs superficial ???
• effect keratinized tissues: epidermis and dermis of
  hair, skin, and nails
• Why they don’t spread deeper? Mechanism
  uncertain
• Below is opposite of your book? Table 19-3
   – Dermatophytoses (caused by one of three
     “dermatophytes”: Microsporum species,
     Trichophyton species, and Epidermophyton
     floccosum)
   – Dermatomycosis (caused by any fungus other
     than the dermatophytes)
           Clinical Classification
• Superficial mycoses (affecting only the outermost
  surface of skin, hair, and nails)
   – Black piedra – hair shaft
   – White piedra – hair shaft
   – Tinea nigra – skin of the palms
   – Tinea versicolor – skin global, affects skin
     pigmentation; light or dark patches
   – Tinea unguium – fungal infection around nails
   – Onychomycosis – similar to Tinea unguium
   – Mycotic keratitis - affecting only the cornea of
     the eye
          Clinical Classification
• Lame use of the term – lame lame lame: if all fungi
  are free-living then all are opportunistic. This is
  laziness and ignorance. I don’t know what
  reasonable scientific explanation would make
  sense out of this.
• Opportunistic mycoses (the implication is that
  they may affect any part of the body)
   – Aspergillosis
   – Candidosis
   – Geotrichosis
   – Phaeohyphomycosis
   – Hyalohyphomycosis
   – Zygomycosis
Terminology and Characteristics
• Fungi do not possess chlorophyll (they
  are nonphotosynthetic)
• Fungi do not have roots, stems and
  leaves, but…
• Fungi do require organic chemicals for
  their carbon and energy source
  (chemoheterotrophs)
Terminology and Characteristics
• Fungi can use non-living sources for
  carbon and energy (saprobes or
  saprophytes) or they can use living cells
  and tissue for carbon and energy
  (parasites or pathogens)
• Fungi can reproduce both sexually and/or
  asexually
• If fungi reproduce sexually they usually
  require two mating types; called + or -
  male vs female?
 Terminology and Characteristics
• Most Fungi grow as one of two
  morphotypes: yeast or molds
• Dimorphic fungi can have either yeast or
  mold forms depending environmental
  conditions
  – They are yeast in vivo or in cultures that
    simulate the human body such as blood agar
    incubated at body temperature in CO2
  – They are moulds in their natural environment
    outside the human body as well cultures that
    contain nutritionally poor media at room
    temperature
      Characteristics of Yeasts
• Yeast are one-celled fungi that reproduce
  asexually by budding (blastoconidia) or
  sexually by ascospores       or
  basidiospores




• If buds elongate and do not detach from their
  parent cell and they form chains of conidia
  resembling the hyphae of molds, these are
  called pseudohyphae – see slide 24

								
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