Protothecosis

Figure 4.34 A: Mucormycosis (Courtesy of Dr. Paul Getz) B: Rhinosporidiosis* C: Rhinosporidiosis* *Reproduced with permission from: Kumari R, Laxmisha C, Thappa, DM. Disseminated cutaneous rhinosporidiosis. Dermatol Online J. Mar 2005;11 (1) :19 D: Protothecosis (Courtesy of Sandra Arduin, Michigan Department of Community Health)
Figure 4.34
A: Mucormycosis
(Courtesy of Dr. Paul Getz)
B: Rhinosporidiosis*
C: Rhinosporidiosis*
*Reproduced with permission
from: Kumari R, Laxmisha C,
Thappa, DM. Disseminated
cutaneous rhinosporidiosis.
Dermatol Online J.
Mar 2005;11 (1) :19

D: Protothecosis
(Courtesy of Sandra Arduin,
Michigan Department of
Community Health
)
(Figure 4.34D)
  • Prototheca wickerhamii, an achlorophyllic algae found in stagnant aqueous sources (lakes, stream, even tap water)
  • Endemic to Southeast Asia
  • Presents after traumatic inoculation as solitary cutaneous plaque or nodule typically involving an extremity, may evolve to umbilicated papules in HIV patients; may also present as olecranon bursitis; immunocompentent patients with limited disease but an immunocompromised person may have widespread disease, including algaemia
  • Histology: morula formation (daughter cells within a theca resembling a soccer ball), 6–10 µm either outside or within macrophage, best seen with GMS or PAS; inhibited by cycloheximide
  • Treatment: excision or tetracycline with amphotericin B