Prototheca wickerhamii
(Tubaki and Soneda, 1959)

Morphology:

  • yeast like colonies, smooth surface and  smooth margin

  • beige or ocher colored.

  • Micro morphology: round single cells (4-10 Ám in diameter) and
    some large Sporangiospores with round endospores inside.

 

Diagnostics

  • plate culture on fungi medium, e.g. Sabouraud-glucose-agar, Kimmig-agar

  • subsequent microscopical  examination of smears with lactophenole cotton blue 
    or with PAS-staining or Immunofluoreszence (pathohistology)

  • Differentiation between P. zopfii and P. wickerhamii by assimilation of Trehalose.
    P. wickerhamii utilize trehalose; P. zopfii could not assimilate this carbon source.  

 

Infections:

Human protothecosis

  • most frequent pathogen of protothecosis of humans.

  • cutaneous form and  systemical form

 

Canine protothecosis

  • just as frequent as P. zopfii

  • cutaneous form and systemical form

 

Bovine protothecosis 

  • only in exceptional cases, usually caused by P. zopfii 

 

Pathogenity

  • facultative pathogen

  • mostly in combination with immunosupression, e.g. AIDS, 
    cortisone therapy, diabetes mellitus or Hodgekin lymphome

 

Immune response

  • induction of specific antibodies of immunglobuline isotypes G and A

  • high resistance to phagozytosis 

  • Persistence and proliferation within macrophages and PMN's