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