practical identification of subcutaneous species
TRANSCRIPT
PRACTICAL IDENTIFICATION OF
SUBCUTANEOUS SPECIES
KIMAIGA H.O
MBChB (University of Nairobi)
SUBCUTANEOUS SPECIES
• Acremonium
• Cladosporium
• Fusarium
• Sporotrichox
Acremonium spp• Macroscopic
morphology• SDA colony texture
•Often compact and moist at first,
•Becoming - powdery, suede-like
•Colony color•May be - white, grey,
pink, rose or orange
• Macroscopic morphology
• Lactophenol cotton blue (LCB) stain
•Hyphae
• Fine and hyaline
•Conidia•One celled
•Hyaline or pigmented
•Globose or cylindrical
•Mostly aggregated in shiny heads at the apex of each phialide
Cladosporium
Fusarium spp
• Macroscopic morphology• SDA colony texture
• Fast growing, woolly to cottony, flat, spreading
• Colony color• Front: white, cream, tan, salmon, cinnamon, yellow, red, violet,
pink or purple
• Microscopic morphology• Lactophenol cotton blue (LCB) stain• Phiolides
• Cylindrical with a small collarette• Solitary or produced as a component of a complex branching
system• Monophialides and polyphialides (in heads or chains) may be
observed
• Macroconidia• Produced from
phialides on unbranched or branched conidophores
• Thick walled• Smooth and cylindrical
or sickle shaped• Distinct basal foot cell
and painted distal ends• Tend to accumulate in
balls or rafts
• Microconidia• Formed on long or
short simple conidophores
• One celled, occasionally 2 or 3 celled
• Smooth, hyaline, ovoid to cylindrical
• Arranged in balls (occasionally in chains)
• Chlamydospores: when present• Sparse,• In pairs, clumps or
chains• Thick walled• Hyaline• Intercalary or terminal
Fusarium spp
S.schenckii
• Macroscopic morphology• SDA colony texture
• Moist and glabrous• Wrinkled and folded
surface• Some spp may produce
short arial hyphae
• Colony color• Pigmentation may vary
from white to cream to black
• Macroscopic morphology• Lactophenol cotton blue
(LCB) stain
• Conidopheres:• Arise at right angles from
the septate hyphae• Visually: solitary, erect
and tapered towards the apex
• Conidia:• Formed in clusters on tiny
denticles• Arrangement often
suggestive of a flower• Ovoid or elongated• Hyaline• One celled and smooth
walled