C' albicans versus C' dublinensis

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C. albicans versus C. dublinensis

• Recently a Candida species isolated from AIDS
  patients appeared to be C. albicans since it was
  germ tube and chlamydoconidia positive
• Closer examination showed it to differ from C.
  albicans by several phenotypic and genotypic
  traits
• The name C. dubliniensis has been proposed for
  this organism

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C. albicans versus C. dubliniensis

• Whether C. dubliniensis needs to be
  differentiated from C. albicans in the mycology
  lab is not clear
• Differentiation could be as simple as culturing
  an isolate at different temperatures or on
  differential media
• C. albicans grows well at 45oC whereas C.
  dubliniensis does not
• C. dubliniensis produces spreading colonies on
  bird seed agar whereas C. albicans grows as
  smooth colonies on this medium

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Candidiasis Candida glabrata

• A.K.A Torulopsis glabrata the taxonomic status
  of this organism is not yet settled - some
  mycologists refer to it as Candida glabrata and
  others call it Torulopsis glabrata
• If it is a Candida species it is morphologically
  very atypical - it does not produce the hyphae or
  pseudohyphae, a characteristic of all other
  Candida species.

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Candidiasis Candida glabrata

• Epidemiology
• Candida (Torulopsis) glabrata is part of the
  human normal microbiota inhabiting mouth, GI
  tract, skin and urogenital tract. It can coexist
  with no harm to the human host or can function as
  a pathogen recent data suggests it may be much
  more prevalent as a human pathogen that
  previously thought
• Predisposing factors that lead to serious
  infections include intravenous catheters,
  malignancy, immunosuppressive therapy, diabetes
  mellitus and antimicrobial therapy same old
  story
• If it is a Candida species its virulence seems to
  be less than C. albicans but greater than other
  Candida species opportunist as are the other
  Candidas

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Candidiasis Candida glabrata

• Clinical Manifestations of Candida (Torulopsis)
  glabrata infections
• Genitourinary tract infections most common
• Nappy rash
• Infections of the lung, kidney, heart, and CNS
• Internal / disseminating infection only occurs in
  immunocompromised patients

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Candidiasis Candida glabrata

• Colonies on primary isolation media are smaller
  than most yeasts, pasty, cream color and
  glistening
• It tends to be more nutritionally fastidious
• Individual cells are very small about half the
  size of other Candida species.
• Other characteristics
• Germ tube negative
• No hyphae, pseudohyphae, or capsules seen on CMT

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Candidiasis Candida glabrata

• Other characteristics
• Small size is quite evident to the trained
  observer on CMT-80
• Urease and birdseed agar are negative
• Assimilates only glucose and trehalose

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Candida glabrata on CMT