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 µm 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