Mycology Slide Set 6

8/2/2019 Mycology Slide Set 6

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X-ray of a pulmonary aspergillosis case



Wet mount preparation in 10% KOH from

a patient sputum with pulmonary aspergillosis.

Note the branching hyphae of the genus

Aspergillus.



This is aspergillosis in the liver tissue showing septate hyphae

with branches.



A silver stained section of a tissueforked with septate hyphae with

branches in 45o angle typical of the

genus Aspergillus.



Occasionally the genus Aspergillus in cavities of

the body could form conidiophores as it does on

cultures on agar plates. This an example of

conidiophores of Aspergillus from a cavity.



Colony of Aspergillus fumigatus with

a typical gray-green colored conidia.



A typical conidiophore of A. fumigatus.Note its smooth-walled and flask-shape

vesicle. A single row of phialids produces

chains of echinulate, globose conidia



Aspergillus terreus is an occasionaletiologic agent of aspergillosis. The

colony is velvety with masses of

cinnamon-buff conidia on the surface



Microscopic features

of a A, terreus colonyshowing a conidiophore

with a dome-like vesicle

and two series of phialids.

Smooth-walled sphericalconidia are produced in

chains from the phialids.



This is a colony of Aspergillus niger. The vegetative

mycelium around the edges of the colony is white or

yellow with large, black conidial heads toward the

center of the colony.



Microscopic features of the conidiophores of A. niger. They

are characterized by a dark pigmentation near the globose

vesicle. Black to brown conidia are observed around the

conidiophores.



Mucocutaneous candidiasis

on the face of a baby

associated with a chronic

granulomatous disease.This disease is observed

in children with various

genetic defects.



This is case of candidiasis with fissures of the mouth

as well as an inactive paronychia.



Candidiasis is not uncommon in babies lacking goodhygienic conditions. Symptoms may become severe

around the face, axillae, or on others areas of the

body. Diaper candidiasis is a good example. This

figure shows a pure culture of Candida albicans

on this baby’s neck.



Onycomycosis is a common form of cutaneous candidiasis.

The surface of the nails appears as a hardened, thickened,

brownish-discolored nail plate.



Vaginal candidiasis better

known as “yeast infection”.

Predisposition factors for

vaginal candidiasis includediabetes, antibiotic therapy,

oral contraceptives, and

pregnancy. This disease is

characterized by the

presence of a thick, yellow,milky discharge and whitish

patches on the surface the

genitalia.



This is pruritus ani due

to colonization of Candida

spp. This condition may

occur after the use of abroad spectrum bacterial

antibiotic for one week

or more.

The most affected arechildren and the elderly

population.



Disseminate candidiasis. The figure shows a kidney after

dissemination of the Candida spp. from the original site.

This patient was debilitated by a acute case of leukemia.





This Gram stained slide is a smear from a mouth

candidiasis case. Note the pseudophyphae (blue

arrows), the budding yeast cells (yellow arrows),

the hyphae (green arrow) and bacteria (arrow heads)



A case of systemic candidiasis. Silver stained slide of a

renal candidiasis showing pseudohyphae and budding

yeast cells.

YeastPsuedohyphae



A close-up view shows yeast colonies of Candida spp. on

Sabouraud dextrose agar from a vaginal sample of

Candidiasis. Note the typical features of the yeast colonies.



The most rapid method

for identification of

Candida albicans in theclinical laboratory is by

checking for the formation

of these germ tubes in

serum at 37o

C after twohours incubation. Germ

tubes have parallel walls.



Candida albicans is the only Candida species that will from

chlamydoconidia in corn meal agar. The chlamydoconidia are

the larger, thicker-walled, spherical cells that have formed on

the tips of hyphae. Small budding yeast cells are also observed



In addition to the germ tube and chlamydoconidia formation

carbohydrate assimilation and/or fermentation are alsouseful to identify Candida and other yeast species. This is the

API 20C identification kit. In this example those cups in which

the three lines are not clear mean positive reaction for that

particular carbohydrate.



Auxanograma is an assimilation test for carbohydrates. In this

example, the yeast strain has been spread on the surface.

Each disc contains the carbohydrate under investigation.

Growth around the disks will results in pH and color change,

(red) meaning that a particular carbohydrate has been used.



This is a case of Candida glabrata in theplacenta. This PAS section shows small

2-3 μm budding yeast cells (arrow).



This is an enlargement of the latter slide

showing a section of a placenta. Note the

many budding yeast cells



Culture plate with Candida glabrata

from the placenta case. Note the typical

yeast colonies.



Microscopic features of C. glabrata from

culture plates (lactophenol blue). Note the

small budding yeast cells.



This API 20C kit shows the assimilation

of glucose and trehalose a feature of C.

glabrata (arrows).



This is a Gram stain from a sputum

showing hyphae and arthrospores of

Geotrichum candidum an opportunistic

pathogen



This is the colony of G. candidum from

the sputum sample. The colony is flat

membranous or mealy-surfaced, waxy,

and white to cream in color.



Microscopic slide of Geotrichum candidum

from a culture plate. Note the presence

of septate hyaline hyphae, and arthroconidia

Arthroconidia

Hyphae



Skin lesions from a case of disseminated

cryptococcosis.



An X-ray of the lung showing a

nonhomogenous mass in the upper right

lung due to Cryptococcus neoformans



A 50% India ink preparation of spinal

fluid shows encapsulated yeast cells

of C. neoformans. This pathogen is the

only known encapsulated fungus



Cryptococcus neoformans has a special tropism forthe central nervous system. This a H&E section of

human brain showing yeast cells surrounded by

capsules.



Colonies of Cryptococcus neoformans

at 24 or 37oC are mucoid, slimy, and

cream to brown in color.



When C. neoformans

is incubated on birdsee agar, the yeast

assimilates creatinine,

resulting in the colonybecoming brown in

color on the medium.

In contrast , Candida albicans remains white

in color in this medium



Spinal fluid sample in 50% India ink. Notethe healthy capsule developed by this

opportunistic fungus. The presence of this

capsule is pathognomonic of cryptococcosis.



The sexual stage of C. neoformans is

Filobasidiella neoformans and it istaxonomically closer to the basidiomycetes

(mushrooms ). The arrows point to the

formation of basidiospores.



Brain showing a case of systemic

zygomycosis. Note the necrotic areas

affected by Mucor sp.



Histopathological section (PAS) of the

brain showing aseptate broad hyphae

typical of the zygomycetes.



Another case of zygomycosis showing

large aseptate broad hyphae.



Example of mycotic abortion of a calf

due to species of Mucor.



A typical colony of the zygomycete

Rhizopus sp. The colony takes all the

petri dish and have a cottony-like

appearance.



The microphotograph shows the

rhizoids (arrow) typical of the genus

Rhizopus. The sporangia is at the top

of the figure (blue arrow)



These sporangia are typical of the species

Mucor. One sporangium has not released

its endospores (arrow).



This is Rhizomucor spp a zygomycete that

can cause systemic infections in immun-

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Mycology Slide Set 6