Subcutaneous Mycoses Flashcards
Dimorphic fungi and fungus-like microorganisms affect the _____ and _____________ tissues.
skin, subcutaneous
Sporothrix schenckii, which is the cause of _____________ in a variety of animal species, but more frequently in ?
sporotrichosis, humans, horses, dogs, and
cats
Histoplasma capsulatum var. farciminosum, is the cause of __________ ____________ in equids (horses, donkeys, and mules)
epizootic
lymphangitis
Oomycosis (Aphanomyces, Lagenidium, Pythium, and Saprolegnia), cause a variety of diseases in ____ and _______ and
miscellaneous conditions involving the ____ and __________ tissues,
including ?
fish, mammals, skin, subcutaneous, chromoblastomycosis, phaeohyphomycosis, and mycetoma.
Sporothrix schenkii is a __________, ________ fungi. In immune-competent people, this disease usually manifests as a _____, ________ _________ of skin and subcutaneous tissue.
* In immune-competent horses and dogs, the disease is usually limited to the _______ or ____________ form, and organisms are typically ______ or ____ within the lesions.
* Disseminated disease is very rare in ______ and _____ unless the patient is
immunosuppressed.
* Cats with sporotrichosis will develop _______ or _______
disease regardless of their immune status at the time of infection.
saprophytic, dimorphic, chronic, ulcerative, lymphangitis, cutaneous, cutaneolymphatic, sparse, rare, horses, dogs, cutaneolymphatic, disseminated
Sporothrix schenkii is a ________ fungus and it exhibits a different morphology depending upon the ________ of
growth. At room temperature (25 ◦C, on Sabouraud’s agar), S.
schenckii grows as a ______.
* At 35–37 ◦C (in tissue or on rich media, e.g., blood agar, incubated at
that temperature), it exists as _______ ________ yeasts (characterized typically by the unique “______ bodies” but yeasts can also be ____ shaped)
* The yeast phase stains with the _____ stain, and either phase accepts _________-type stain (e.g., Wright’s or Giemsa) or _____ stains (periodic acid Schiff, Grocott methenamine silver, and Gridley).
dimorphic, conditions, mold, budding, pleomorphic, cigar, round, Gram’s, Romanowsky, fungal
List the cell wall components of Sporothrix schenkii
SLAMPP
* Adhesins affinity for extracellular matrix proteins
* Lipid inhibits phagocytosis by monocytes and macrophages.
* Melanin protects from the effects of reactive oxygen intermediates within
phagolysosomes of phagocytic cells.
* Peptide-rhamnomannan acts as an immunosuppressive substance by
suppressing the liberation of proinflammatory cytokines by phagocytic cells.
* Sialic acids inhibit uptake by phagocytic cells and directs complement proteins
toward the degradative pathway, rather than generating effective opsonizing
fragments and anaphylatoxins needed to generate an effective inflammatory
response.
* Proteinases (secreted enzymes) unknown activity/hydrolyze stratum
corneum
Sporothrix schenkii
Ecology
* Soil rich in ______ and organic matter; it has also been isolated on
many ____ plants
* Disease has been reported in people, dogs, cats, horses, mules,
donkeys, goats, cattle, rats, mice, hamsters, foxes, birds, camels,
dolphins, armadillos, and chimpanzees.
* The disease is most common in the ___, ___, and _____ where it
occurs in multiple forms. Human infections are often associated with ______ gardening (and often called a “______ gardener’s disease”)
decaying, live, cat, dog, horse, rose, rose
Sporothrix schenkii
Transmission/Pathogenesis
Sporothrix schenkii
Immunology/Diagnsotic/Treatment
* ______-mediated immunity is significantly related to resistance. No ______ immunization procedures exist.
* Identification of the organism is _______ forward assuming the classic ____ to _____-shaped yeast forms (____ bodies) are seen
(exudates/biopsies) (staining/culture)
* Immunofluorescence, latex agglutination, agar gel diffusion, PCR
(Chitin synthase 1)
* Susceptible to _______/_________ iodides as well as ?
Cell, artificial, straight, oval, cigar, cigar, sodium, potassium, ketoconazole,
amphotericin B + flucytosine (deep and disseminated forms).
What can be seen in the image below?
What can be seen in the image below?
What can be seen in the image?
Sporothrix schenckii
What can be seen in the image?
Sporothrix schenckii
What can be seen in the image?
Sporothrix schenckii
What can be seen in the image?
Sporothrix schenckii
What can be seen in the image?
Sporothrix schenckii
What can be seen in the image?
Sporothrix schenckii
What can be seen in the image?
Sporothrix schenckii
Histoplasma capsulatum
* H. capsulatum is a _________ fungus existing as a _____ at 25–30 ◦C
( _____________ phase) and as a _____ at 37 ◦C (_________ phase)
* This fungus has three varieties: ?
dimorphic, mold, saprophytic, yeast, parasitic, H. capsulatum var. capsulatum, H.
capsulatum var. duboisii, and H. capsulatum var. farciminosum.
Varieties H. capsulatum and H. duboisii cause __________, a systemic fungal disease.
* Variety farciminosum causes _________ _________ (__________), a chronic ____________ disease typically involving the ____ and __________ that mainly affects horses, donkeys, and mules but has
also been reported in camels, cattle and dogs.
histoplasmosis, epizootic lymphangitis, pseudoglanders, pyogranulomatous, skin, lymphatics
Histoplasma capsulatum var. farciminosum
* __________ fungus, produces ________ yeasts in tissue, and usually _____ hyphae in its mycelial form when grown at ___ ◦C or _____ temperature.
* Exceptionally, ? are seen.
* The yeast phase is best demonstrated with a ___________-type stain (e.g., Wright’s or Giemsa) or _______ stains (periodic acid Schiff, Grocott
methenamine silver, and Gridley).
* Grows on common laboratory media (_____) 25–30 ◦C, taking several weeks to form a _______, ____ to _____ colony.
* Conversion of mold to yeast on _____-containing agar requires incubation
at 37 ◦C under 15–20% CO2.
Dimorphic, budding, sterile, 25, room, arthroconidia, chlamydoconidia, and spherical, thick-walled
macroconidia, Romanowsky, fungal, SDA, cottony, white, brown, blood
H. capsulatum var. farciminosum is quite resistant to _____ and ______ agents. It survives in ___ at ambient temperatures for _____ (several weeks in _____ and ______) and at ________
temperature or in a _______ form for years.
physical, chemical, soil, months, corrals, stables, refrigerator, desiccated
The primary reservoir for Histoplasma species is ________-rich ____.
nitrogen, soil
Histoplasma infection occurs through skin _________.
* Yeast from skin lesions, or nasal and/or ocular exudates ???
* _____ form from soil
* Fomites: ______ and _____ equipment
* __________ may play a role in the transmission
wounds, Mycelial, grooming, harness, Arthropods
Histoplasma capsulatum var. Farciminosum
Pathogenesis
Histoplasma capsulatum var. Farciminosum
Seasonal peaks suggest __________ transmission.
arthropod
Histoplasma capsulatum var. Farciminosum disease mainly affects ______ but (3) may also be
affected. ______ horses (less than __ years of age) are most susceptible.
equids, cattle, camelids, and dogs ,Young, 6
For patients infected with Histoplasma capsulatum var. Farciminosum, ____-mediated immunity is probably the key host defense.
Cell
How can you identify H. capsulatum vaar. Farciminosum
* ______ demonstrable by agar gel diffusion or by the serum agglutination test.
* Direct examination of stained exudates ( (2?) stained) or _____ material (hematoxylin–eosin, periodic acid Schiff, and Grocott methenamine
silver) may reveal intracellular (within _______) or extracellular
characteristic yeasts.
Antigens, Wright’s or Giemsa, biopsy, macrophages
H. capsulatum var. farciminosum grows on _____.
SDA
Treatment for Histoplasma capsulatum var. Farciminosum: ____________ have been relatively successful. ____________ __ has been
used with some success. Itraconazole and fluconazole may also be used.
griseofulvin, Amphotericin B
These animals are suffering from?
Histoplasma capsulatum var. Farciminosum
Phytiosis is also known as?
(Swamp cancer/”Florida horse leeches”)
The agent that causes Phytiosis is an ________ _________ (“aquatic fungus”) with ____ (4 μm), sparsely _____ hyphae.
aquatic oomycete, wide, septate
Phytiosis (pyogranulomatous disease, caused by ________ __________, of a variety of animal species). __________ conditions (pythiosis) of dogs (“ ______ cancer”), horses (“ ______ horse leeches”), cattle, cats, and people.
* In North America this disease is seen most frequently diagnosed along the ______ ______. _____ and ____ are the species most commonly affected.
Pythium insidiosum, Pyogranulomatous, swamp, Florida, Gulf Coast, Dogs, horses
Phytiosis causes ?
ulcerative fibrogranulomatous or pyogranulomatous and eosinophilic cutaneous and subcutaneous lesions.
Phytiosis Pathogenesis/ Diagnostic/
Treatment
* Lesions in horses are typically _____, _________ swellings, usually on ________, _____ trunk, or ____. The ____ mucosa may be involved. Hyphae are demonstrable within _________ coagula (termed “ ________ ”or “ ________” in horses) consisting of necrotic macrophages (including _______ and ________ macrophages), eosinophils.
large, exudative, extremities, ventral, head, nasal, granulomatous, kunkers, leeches, epithelioid, multinucleated
How would you diagnose a patient with Phytiosis?
- Cytology, ELISA, PCR, Immunohistochemistry.
- Cultural techniques are tedious and time consuming and entail
growth of a mold-like microorganism on SDA,24–48 h at 30 ◦C.
How would you treat a patient with Phytiosis?
- Amphotericine B, Immunotherapy utilizing killed whole organisms or
extracts has shown promise.
What can be seen below?
What can be seen here?
What can be seen here?
What can be seen here?
Chromoblastomycosis and phaeohyphomycosis are caused by _____-
pigmented (___________) fungi.
dark, dematiaceous
Chromoblastomycosis is rare in __________ mammals, but occurs in _____ and ______.
nonhuman, frogs, toads
Phaeohyphomycosis is seen sporadically in ? and may be ________.
cats, dogs, horses, cattle, and goats, systemic
Cladophialophora bantiana is the fungus most commonly seen in _____ and ______, with ________ nervous system localization frequently observed.
dogs, cats, central
Chromoblastomycosis and Phaeohyphomycosis
Pathogenesis/Diagnostic/Treatment
* The agents, _____-and ___-associated saprophytes, enter through ____ and
multiply ___________, causing __________ reactions. No _____ colonies
or ____ are seen. _______ or larger swellings develop, which may ______ and discharge ____.
soil, plant, skin, subcutaneously, pyogranulomatous, tissue, granules, Nodular, ulcerate, pus
Diagnosis of Chromoblastomycosis and Phaeohyphomycosis is made by:
1. _____ and ______. _______ bodies (chromoblastomycosis)
and _______ (phaeohyphomycosis) are seen in stained (?) biopsy sections.
2. Culture, on _________ agar without ______, often requires lengthy
incubation. The resulting colonies range from _____ to _____ to ______, depending
on the color of _____ of fungus involved.
3. Lesions are _______, but may ______.
* Treatment: flucytosine, itraconazole, amphotericin B, and ketoconazole has given mixed results
biopsy, culture, Sclerotic, hyphae, hematoxylin–eosin, periodic acid Schiff, and Grocott methenamine silver, Sabouraud’s, inhibitors, olive, brown, black, species, excised, recur
Eumycotic Mycetoma is a fungi associated with eumycotic mycetoma including ?
- All are saprophytes that presumably enter via a _______.
Pseudallescheria boydii, Cochliobolus spiciferus (the sexual forms of Scedosporium apiospermum and Bipolaris spicifera, respectively), and Curvularia
geniculata.
wound
- List the characteristics of a mycetoma. 2. They may be associated with bacteria, most notably an actinomycete such as members of the genus ______ or _____
(actinomycotic mycetoma).
Swelling, granule formation, and discharging sinus tracts are characteristics.
Nocardia, Actinomyces
Eumycotic Mycetoma gungal colonies are surrounded by ________ bordered by ________ reactions. _______ _____ carry pus and granules, consisting of ______ and inflammatory components, to the surface.
suppuration, granulomatous, Sinus tracts, microorganisms
Treatment of Eumycotic Mycetoma is ______ if possible. _____ agents (azoles and
amphotericin B) have been disappointing.
excision, Antifungal
- Rhinosporidiosis is the cause of this disease is ?
- It causes ________ ________ type of infection at ___________
junction
Rhinosporidium seeberi.
chronic granulomatous, mucocutaneous
Rhinosporidiosis affects which species? Rare in which species?
horses, cattle, mules, dogs, goats, and wild waterfowls. Infection, though rare, occurs in humans.
Rhinosporidiosis results in the formation of ____________-like growths, also known as ______, is very characteristic of infection caused by this fungus.
cauliflower, polyps
Rhinosporidiosis occurs mostly in _______ and _______ countries; however, sporadic cases have been reported in the _______ ______.
tropical, subtropical, United States
Diagnosis of Rhinosporidiosis is based on _______ lesion and microscopic examination of _____ sections or _______ from polyps. On tissue section, presence
of large _____ (200–300 μm) filled with _______ is sufficient to make a definitive diagnosis of this disease. On cytologic preparations, however, ______ are rarely seen and the numerous _______ are
the typical finding (Figure 46.2).
* Treatment is not effective. _______ excision is practiced, but many
lesions ____.
gross, tissue, discharge, sporangia, endospores, sporangia, endospores, Surgical, recur
What can be seen here?
Rhinosporidiosis
What can be seen here?
Rhinosporidiosis
What can be seen here?
Rhinosporidiosis
