Penicilliosis

(Figure 4.35C)
  • Penicillium marneffei
  • Carried by healthy bamboo rats
  • Presents with acneiform papules resembling molluscum contagiosum (seen especially in AIDS patients)
  • Histology: suppurative granulomatous inflammation with intracellular and extracellular yeast
   
 
Following infections may resemble molluscum-like lesions: coccidioidomycosis, cryptococcosis, histoplasmosis, penicilliosis
 
   

   
 
Organisms found within histiocytes: histoplasmosis, granuloma inguinale, leishmaniasis, penicilliosis (His GIrLPenelope)
 
   

   
 
Table 4-15 Microscopic Appearance of Select Fungi and Protozoa
 OrganismDescriptionSize (µm)
 
Histoplasma capsulatum
Round yeast with surrounding thin, clear halo; distributed evenly within cytoplasm of histiocyte
2–4
 
Leishmania spp.
Small, grouped intracellular organisms with rod-shaped kinetoplast, no halo
2–4
 
Apergillus spp.
Septate hyphae with 45° branching, often in blood vessels
2–4
 
Penicillium marneffei
Oval to round yeast, may be intracellular or extracellular
3–5
 
Sporothrix schenckii
Round to cigar-shaped yeast, difficult to find
3–8
 
Prototheca spp.
Spherule with morula formation with numerous septations (resembles soccer ball)
3–11
 
Blastomyces dermatitidis
Thick-walled spores, characteristic broad-based budding
8–15
 
Cryptococcus neoformans
Budding yeast with prominent mucinous capsule (does not stain with H&E)
5–20
 
Coccidioides immitis
Double contoured spheres with endospores
10–80
 
Mucor spp.
Broad hyphae with 90° branching
10–25
 
Paracoccidioides brasiliensis
Characteristic buds resembling mariner’s wheel
5–60
 
Rhinosporidium seeberi
Spherule with endospores (6–10 µm)
250–500
      
 
   





Figure 4.35 A: Alternaria spp.* B: Fusarium spp.* C: Penicillium spp.* *Courtesy of Sandra Arduin, Michigan Department of Community Health
Figure 4.35
A: Alternaria spp.*
B: Fusarium spp.*
C: Penicillium spp.*
*Courtesy of Sandra Arduin,
Michigan Department of
Community Health