Transcript wet conidia - Squarespace

Fungi Identification
a dichotomous key approach
Microscopic appearance of
colonies:
budding cells
few or no
hyphae
hyphae seen
Macroscopic appearance of
colonies:
colonies black
Aureobasidium
Chapter 8
colonies
white
cream
pink
red
Yeas
t
Hyphal
appearance:
septate
aseptate
Mucoraceous moulds
Conidial
appearance:
arthroconidia
Other forms
(other forms
absent)
(arthroconidia
absent)
Chapter 3
Conidia formed in
chains:
present
absent
Conidial chains in
branches:
present
absent
CHAPTER
6
CHAPTER
7
Conidial chain
arrangement:
Positive for
dermatophyte
chains formed
singly on sides
of hyphae or on
short branches
Negative for
dermatophyte
CHAPTER 4, 5,
6
chains formed
in succession
at the same
point,
aggregating in
masses
fruiting bodies
present?
CHAPTER
8
CHAPTER
10
ARTHROSPOR
IC MOULDS
Colony
appearance:
colony
dark brown or
black
Neoscytalidium dimidiatum
colony white or
cream
ARTHROSPOR
IC MOULDS
Arthrospore
arrangement:
Arthrospores
regularly
alternating with
empty cells
Arthrospores
not separated
by empty cells
ARTHROSPOR
IC MOULDS
Arthrospore
Size:
Wider than
2 microns
Mostly 1 - 1.5
microns wide
Coccidioides spp
Malbranchea spp.
ARTHROSPOR
IC MOULDS
Colony
morphology
Colony with
little aerial
mycelium
Geotrichum spp OR
Trichosporon spp
Colony floccose
ARTHROSPOR
IC MOULDS
Culture growth speed:
Rapid growth
(diameter >20mm
in 1 week)
Slow growth
Onychocola canadensis
ARTHROSPOR
IC MOULDS
Arthrospore numbers:
abundant, 4-8
microns wide,
rounded
appearance
few, 2-5
microns wide,
flat-ended
Hyaline variant of
Neoscytalidium dimidiatum
Basidiomycete moulds
ARTHROSPOR
IC MOULDS
Presence of
blastoconidia:
Present
Absent
Trichosporon spp
Geotrichum spp
DERMATOPHYT
IC MOULDS
Pattern of
conidia:
Macroconidia
predominant
Microconidia
predominant
Neither macro
nor micro
conidia present
DERMATOPHYT
IC MOULDS
Surface of
macroconidia:
Rough
Smooth
DERMATOPHYT
IC MOULDS
Presence of terminal beak
on macroconidia
Present
Absent
Microsporum gypseum
Microsporum fulvum
DERMATOPHYT
IC MOULDS
Size of
Macroconidia
Large
>50 microns
Microsporum canis
Smaller
<50 microns
Microsporum equinum
DERMATOPHYT
IC MOULDS
Colony
colour:
Khaki-brown to
greenish-yellow
White, cream or
yellow
Some purple
coloration
Epidermophyton floccosum
Trichophyton terrestre
Trichophyton ajelloi
Trichophyton rubrum
(granular form)
DERMATOPHYT
IC MOULDS
Colony
morphology
floccose/velvety,
white with redbrown reverse,
peg-like
microconidia
Trichophyton rubrum
velvety/granular,
cream with dark
brown reverse,
round microconidia
Colony:
OTHERWISE
DERMATOPHYT
IC MOULDS
Microconidia
number:
Spiral hyphae,
microconidia rare
(foot isolate)
brown veins on
colony reverse,
spiral hyphae,
microconidia
common
Trichophyton interdigitale
Trichophyton mentagrophytes
DERMATOPHYT
IC MOULDS
Microconidia
shape
small and
peg-like
small, ovalround with a
wide base
larger, oval
(colony with brown
reverse)
DERMATOPHYT
IC MOULDS
Colony
Morphology:
flat, white,
velvety,
bright yellow
reverse
buff-cream,
velvety, brown
reverse with
yellow edge
Trichophyton erinacei
Trichophyton equinum
floccose, white,
reverse NOT
yellow
DERMATOPHYT
IC MOULDS
Colony Growth
Rate:
Slow-growing
Intermediate
Rapid
(<10 mm/wk)
(10-15mm/wk)
(20-30mm/wk)
Trichophyton verrucosum
(sporulating variants)
Trichophyton rubrum
(poorly-pigmented variants)
Trichophyton interdigitale
(downy form)
DERMATOPHYT
IC MOULDS
Colony
Morphology
heaped, pink or
yellow tinge,
reverse yellow,
reflexive branching
at colony edge
(slow)
reverse brownish,
broad-based
microconidia,
formed at end of
hyphal side
branches
Trichophyton soudanense
Microsporum persicolor
DERMATOPHYT
IC MOULDS
Colony
Morphology
granular/velvety,
reddish colour,
reverse darkbrown, clear white
edge
granular/velvety,
brown to cream,
reverse dark-brown
with colourless
edge
Trichophyton rubrum
(granular form)
Microsporum tonsurans
DERMATOPHYT
IC MOULDS
Growth Rate:
Moderately Rapid
(>15mm/wk)
Slow
(<15mm/wk)
DERMATOPHYT
IC MOULDS
Colony
Morphology:
Densely floccose
Trichophyton rubrum
Loosely floccose or
velvet
DERMATOPHYT
IC MOULDS
Colony
Colour:
Reverse pale
pinkish-brown,
pectinate hyphae
seen
Microsporum audouinii
Reverse yellow
DERMATOPHYT
IC MOULDS
Colony
Colour:
Reverse intense
orange-yellow,
mostly no aerial
hyphae
Trichophyton interdigitale
(nodular form)
Reverse clearyellow, mostly
floccose
Microsporum canis
DERMATOPHYT
IC MOULDS
Colony
Colour:
dark purple-brown,
little or no aerial
growth
Trichophyton violaceum
white, grey or
cream,
floccose or folded
DERMATOPHYT
IC MOULDS
Colony
Morphology:
colony strongly
folded
colony almost
microscopic,
floccose
Trichophyton verrucosum
DERMATOPHYT
IC MOULDS
Microscopic
appearance:
Nail-head hyphae
and favic
chandeliers
present, grows
without thiamine
Trichophyton schoenleinii
Nail-head hyphae
and favic
chandeliers absent,
thiamine dependent
Trichophyton concentricum
Order
onygenales
Presence of
conidia:
absent
Paracoccidioides brasiliensis
present
Order
onygenales
Conidia
morphology:
conidia large,
spherical,
rough-walled or
tuberculate
Histoplasma capsulatum
Not as
described
Order
onygenales
Conidia
size:
small
<4 microns long
longer than
4 microns
Order
onygenales
Conidia
arrangement:
broad-based on
acutely angled
conidiophores
Geomyces pannorum
very narrow
based, on sides
of hyphae or on
short stalks
Blastomyces dermatitidis
Order
onygenales
Colony
morphology:
cinnamon-brown in
centre, some
conidia on swollen
hyphal cells
Myceliopthora thermophila
white to cream in
centre, conidia
NOT on swollen
hyphal cells
Chrysosporium keratinophilum
dematiaceous
hyphomycetes
Conidial
forms:
Single-celled
conidia
Multi-celled
conidia
dematiaceous
hyphomycetes
Colony
morphology:
mucoid, white
or pale pink
turning dark
later
floccose or
velvety, brownolive colour
dematiaceous
hyphomycetes
Conidia
morphology:
conidia
produced in
clusters on the
sides of the
hyphae
Aureobasidium pullulans
conidia
produced in
terminal
rosettes on
denticles
Sporothrix schenkii
dematiaceous
hyphomycetes
Conidia
morphology:
conidia
produced in
chains
conidia NOT in
chains
dematiaceous
hyphomycetes
Conidia chain length and
form:
conidia chains
long and rarely
branching
conidial chains
short and
heavily
branched
dematiaceous
hyphomycetes
Growth
requirements:
no growth or
very poor
growth at 37 C
Cladeophialophora carrionii
good growth at
37 C and 40 C
Cladeophialophora bantiana
dematiaceous
hyphomycetes
Conidial wall
texture
conidia roughwalled
Cladiosporium herbarum
conidia smoothwalled
dematiaceous
hyphomycetes
Conidial
shape:
Most conidia
round
Cladosporium sphaerospermum
Most conidia
oval or lemon
shaped
dematiaceous
hyphomycetes
Conidial chain
length:
conidial chains
very short and
compact
Fonsecaea pedrosi
conidial chains
longer, more
divergent
Cladosporium cladosporioides
dematiaceous
hyphomycetes
Conidia
morphology:
conidia
elongate, less
than 2 microns
wide
Rhinocladiella atrovirens
conidia broadly
oval, more than
2 microns wide
Rhinocladiella mackenziei
dematiaceous
hyphomycetes
Conidia
cellularity:
conidia all twocelled and thinwalled
Ochroconis gallopava
conidia with
more than two
cells
dematiaceous
hyphomycetes
Conidia
septa:
some conidia with
oblique or
longitudinal septa in
addition to
transverse septa
conidia with
transverse
septa only
dematiaceous
hyphomycetes
Conidia
morphology:
conidia in chains,
most often > 3,
most conidia with
apical beak
Alternaria alternata
conidia formed
singly or in chains
of 2-3, mostly
without a beak
Ulocladium chartarum
dematiaceous
hyphomycetes
Conidia
morphology:
Conidia
symmetrical
Curvularia lunata
Conidia oval or
asymmetrical
dematiaceous
hyphomycetes
Conidial septa and
hila:
conidia oval
with few septa
and hila not
protruding
conidia oval
with many
septa and
strongly
protruding hila
dematiaceous
hyphomycetes
Number of
septa:
conidia mostly
with five septa
Bipolaris hawaiiensis
conidia mostly
with three septa
Bipolaris australiensis
dematiaceous
hyphomycetes
Conidia
morphology:
conidia widest
near the base
conidia NOT widest
near the base,
some worth
projections on
conidia walls
Exserohilum mcginisii
dematiaceous
hyphomycetes
Conidia
morphology:
conidia with
both the basal
septum and
apical septum
dark
Exserohilum
rostratum
conidia with basal
septum only darker
than the others
Exserohilum longistratum
moulds with chains of dry conidia arising
from phialides
Presence of vesicles at the tip
of
conidiophore stalk
Present
Absent
aspergillus species
complexes
Colony
colour:
Some shade of
green
Not green
aspergillus species
complexes
Vesicle
shape:
elongated
vesicle
(>100 microns
long)
Aspergillus clavatus
vesicles
rounded
aspergillus species
complexes
Colony
morphology:
colony
uniformly
yellow-green,
stalks rough
Aspergillus flavus
Colony dark green,
sometimes with
yellow areas, stalks
smooth
aspergillus species
complexes
Presence of metulae
(cell layer between vesicle and spore-forming
phialides)
absent
present
aspergillus species
complexes
Distribution of
phialides
Over upper
two-thirds of
small flattened
vesicle
Aspergillus fumigatus
Over entire
surface of
large, round
vesicle
Aspergillus glaucus
aspergillus species
complexes
Colony
morphology
stalks pale
brown, heads
columnar in old
cultures
Aspergillus nidulans
Stalks
colourless,
heads globose
or irregular
Aspergillus versicolor
aspergillus species
complexes
Colony
morphology
Stalks rough,
colony orange
brown
Aspergillus ochraceus
Stalks brown or
yellow
Stalks
colourless
aspergillus species
complexes
Colony
colour
dull grey to
charcoal
yellow to buff
Aspergillus ustus
Aspergillus flavipes
aspergillus species
complexes
Colony
colour:
black or dark
brown
cinnamon-brown
to
sand-coloured
white or pale
cream
Aspergillus niger
Aspergillus terreus
Aspergillus candidus
other chain-forming
enteroblastic moulds
Colony
colour:
colony green
Penicillium spp
colony not
green
other chain-forming
enteroblastic moulds
Conidia
morphology:
conidia large,
round, with a
flat scar
Scopulariopsis brevicaulis
conidia small,
oval, with a
minute scar
other chain-forming
enteroblastic moulds
Conidia
colour:
colony pale
purple
colony
greenish-buff
Purpureocillium lilacinum
Paecilomyces variotti
moulds with wet conidia
adhering in masses
Colony
colour:
white,
grey,
pink OR
red colonies
brown
OR
black colonies
moulds with wet conidia
adhering in masses
Colour of old
colonies:
remain white or
pink without
brown pigment
develop dark
pigment
moulds with wet conidia
adhering in masses
Presence of
macroconidia:
absent
present
(only unicellular
microconidia
present)
moulds with wet conidia
adhering in masses
Macroconidia
morphology:
macroconidia
straight with
round ends
Fusarium lichenicola
macroconidia
curved with
pointed ends
moulds with wet conidia
adhering in masses
Macroconidia
morphology:
macroconidia
mostly twocelled
macroconidia
on
polyphialides
Fusarium dimerum
Fusarium semitectum
moulds with wet conidia
adhering in masses
Microconidia
arrangement:
microconidia on
short phialides
microconidia on
long phialides
moulds with wet conidia
adhering in masses
Microconidia
morphology:
microconidia
elongated,
some forming
chains
microconidia
ovoid to kidneyshaped, not in
chains
Fusarium proliferatum or
Fusarium verticilloides
Fusarium oxysporum
moulds with wet conidia
adhering in masses
Conidia
size:
conidia mostly
wider than
2 microns
conidia
narrower than
2 microns
Fusarium
solani
Acremonium strictum
moulds with wet conidia
adhering in masses
Colony
morphology:
colonies mostly
glabrous
(at least near the
edge)
colonies mostly
floccose
moulds with wet conidia
adhering in masses
Phialide
morphology:
long and
tapering
reduced to
short
outgrowths of
hyphal cells
short annelids
with swollen
bases
Acremonium kiliense
or
Phaeoacremonium parasiticum
Lecythophora mutabilis
Scedosporium prolificans
moulds with wet conidia
adhering in masses
Conidia
size:
conidia large,
6 - 12 microns
long
conidia smaller,
3 - 7 microns
long
Scedosporium apiospermum
Phaeoacremonium parasiticum
moulds with wet conidia
adhering in masses
Presence of collarettes
on
conidiogenous cells:
distinct
collarettes
present
collarettes
absent
moulds with wet conidia
adhering in masses
Collarette
morphology:
minute and
cylindrical
flared or
reflexed
cup-shaped or
funnel-shaped
Phaeoacremonium parasiticum
Pleurostomophora richardsiae
Phialophora verrucosa
moulds with wet conidia
adhering in masses
Presence of two-celled
yeasts:
two-celled
yeasts
abundant; large
annellidic pegs
Hortaea werneckii
two-celled
yeasts absent,
minute
annellidic pegs
moulds with wet conidia
adhering in masses
Conidia
arrangement:
branched
conidiophores
of thick-walled
segments
Exophalia spinifera
conidia borne
on sides of
hyphae, or on
simple
branches
conidia borne
on short
annelids with
swollen bases
Scedosporium prolificans
moulds with wet conidia
adhering in masses
Growth
features:
grows at 40C;
nitrate test
negative
(some conidia formed
without obvious
annellidic pegs)
Exophalia dermatitidis
no growth at
40C, nitrate test
negative
(annellidic pegs
visible)
Exophalia jeanselmei
mucoraceous
moulds
Sporulation on Sabouraud’s Dextrose
Agar
Yes
No
mucoraceous
moulds
Colony morphology and
growth:
colonies
floccose, rapid
growth at 37C
colonies
floccose, no
growth at 37C
colonies
membranous
and waxy, slow
growing
mucoraceous
moulds
Spore formation:
spores
produced
outside a
vesicle
Cunninghamella bertholletiae
spores
produced inside
a sporangia
mucoraceous
moulds
Sporangia
morphology:
sporangia with
funnel-shaped
bases
Lichtheimia corymbifera
sporangial base
narrowing
abruptly to a
stalk
mucoraceous
moulds
Stalk
morphology:
stalks with a
few side
branches
stalks
unbranched
mucoraceous
moulds
Branching of
sporangia
one or two
small sporangia
just under main
sporangia
branches more
widely spaced,
often curved
Rhizomucos pusillus
Mucor circinelloides
mucoraceous
moulds
Colony
morphology:
colony 3-5mm
deep,
sporangia grey
Rhizomucos pusillus
colony filling
the plate air
space,
sporangia black
mucoraceous
moulds
Stalk and spore
morphology:
stalks about
500 microns
long, spores 46 microns
stalks over
1000 microns
long, spores 68 microns
Rhizopus microsporus
Rhizopus arrhizus
mucoraceous
moulds
Sporangia morphology and
Presence of Rhizoids:
sporangia
black, rhizoids
prominent at
base of stalk
Rhizopus stolonifer
sporangia pale
or brownish,
rhizoids absent
mucoraceous
moulds
Colony
colour
colonies pale
yellow
Mucor hiemalis
colonies pale
brown,
some stalks with
chlamydospores
Mucor racemosus
mucoraceous
moulds
Spore morphology:
spores without
conical papillae
spores with
conical papillae
Basidiobolus ranarum
Conidiobolus coronatus
mucoraceous
moulds
Nature of
spores:
motile
zoospores
produced in
liquid culture
Pythium spp.
mucoraceous
sporangia
produced on
special media
mucoraceous
moulds
Sporangia
morphology:
sporangia on
funnel-shaped
bases
sporangia with
apical tubular
extensions
Apophysomyces elegans
Saksenaea
vasiformis
sporangia
round,
rupturing without
leaving a columella
Mortierella wolfii
moulds that produce macroscopic
fruiting bodies
and miscellaneous moulds
Production of fruiting
bodies:
within 2 weeks
after 2 weeks
fruiting bodies
absent
moulds that produce macroscopic
fruiting bodies
and miscellaneous moulds
Fruiting body
morphology:
pale-walled
fruiting bodies
dark-walled
fruiting bodies
moulds that produce macroscopic
fruiting bodies
and miscellaneous moulds
Colony
colour:
colonies white
to buff coloured
colonies dark
purple
Aphanoascus fulvescens
Monascus ruber
moulds that produce macroscopic
fruiting bodies
and miscellaneous moulds
Fruiting body
morphology:
thick-walled
ascocarps,
covered in long
brown hyphae
Pycnidia, with
thin smooth
walls
Chaetomium spp.
Phoma herbarum
moulds that produce macroscopic
fruiting bodies
and miscellaneous moulds
Fruiting body
morphology:
loose network
of dark hyphae
Myxotrichum deflexum
flattened, palecoloured with
gills
Schizophyllum commune
black, with a
definite wall
moulds that produce macroscopic
fruiting bodies
and miscellaneous moulds
Fruiting body
morphology:
thick-walled
ascocarps,
containing asci
Pycnidia, with
thin smooth
walls
moulds that produce macroscopic
fruiting bodies
and miscellaneous moulds
Ascospore
morphology:
large, mostly
five-celled
small, twocelled,
ascocarp wall
of interlocking
plates
long, flexuous,
with tapered
ends
Leptosphaeria senegalensis
Neotestudina rosatii
Piedraia hortae
moulds that produce macroscopic
fruiting bodies
and miscellaneous moulds
Conidia
morphology:
conidia large,
two-celled
when mature
conidia small,
one-celled,
pycnidia with
spines
Lasiodiplodia theobromae
Pyrenochaeta
romeroi
moulds that produce macroscopic
fruiting bodies
and miscellaneous moulds
Colony
morphology:
colony flat or
folded, velvety,
with diffusing
brown pigment
colony domed,
densely floccose,
without diffusing
pigment
Madurella mycetomatis
Madurella grisea group
identification of
yeasts
Colony
morphology:
minute colonies
on glucose
peptone agar
presumptive
Malassezia furfur
pink or red
colonies on
glucose
peptone agar
presumptive
Rhodotorula spp OR
Sporobolomyces spp
white or cream
colonies on
glucose
peptone agar
identification of
yeasts
Germ Tube
test:
positive
Candida albicans
Candida dubliniensis
Candida africana
negative
identification of
yeasts
Presence of
capsule:
present
presumptive
Cryptococcus spp.
absent
identification of
yeasts
Urease
test:
positive
presumptive
Cryptococcus spp.
OR Trichosporon spp
OR Malassezia pachydermatis
negative
identification of
yeasts
Presence of chlamydospores
on cornmeal agar:
present
Candia albicans
Candida dubliniensis
negative
identification of
yeasts
Presence of arthrospores
on cornmeal agar:
present
negative
identification of
yeasts
Presence of budding cells
on cornmeal agar:
negative
present
presumptive
Trichosporon spp
OR Saprochaete capitata
dichotomously
branching hyphae
present
Geotrichum candidum
identification of
yeasts
Pseudohyphae
present:
present
presumptive
Candida spp
negative
Neoscatylidium dimidiatum
Microscopic
Features
Macroscopic
Features
dy/dx:
clinical
significanc
e
skin and nail infections among
immigrants from the tropics and
sub-tropics.
Not contagious (unlike
dermatophytosis)