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− | {{unfinished}}
| + | #REDIRECT[[:Category:Yeast-like Fungi]] |
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− | {{toplink
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− | |linkpage =Fungi
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− | |linktext =FUNGI
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− | |pagetype=Bugs
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− | <br>
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− | ==Candidosis==
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− | *''Candidia albicans'' is the most important species
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− | **''C. tropicalis'' and ''C. pelliculosa'' are other important species
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− | *World wide distribution
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− | *Usually an endogenous mycoses
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− | *Noramlly present on skin, vagina and in the [[Alimentary - Anatomy & Physiology|GI tract]]
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− | *Immunocompromised animals may show symptoms
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− | *Usually lesions on mucous membranes and at mucocutaneous junctions
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− | *Many species have been implicated in bovine mastitis
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− | *''C. albicans'' has been isolated in porcine stomach ulcers
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− | *''C. rugosa'' has been implicated in pyometra in mares
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− | *Infection of the crop, oesophagus and mouth occur in poultry and other birds leading to 'sour crop'
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− | **White-grey lesions in mouth which adhere loosly to the mucous membrane
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− | **Crop wall may be thickened
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− | **Crop wall may be covered by a yellow-white necrotic material
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− | **Underlying tissue is inflammed
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− | *Causes thrush in humans
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− | *''C. albicans'' causes metritis and vaginitis in mares and genital candidiosis in stallions (and bulls)
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− | *Skin scrapings in 20% KOH for microscopy
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− | *Diphtheritic membranes, pus and fluids can be examined by Lactophenol Cotton Blue and stained by Gram or Methylene Blue
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− | *Gram positive, oval, thin-walled budding cells with hyphal fragments
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− | *Grow on blood agar and Sabouraud's Dextrose agar producing soft, creamy colonies in 24-48 hours
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− | *Grossly:
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− | **Exudative, papular, pustular to ulcerative dermatitis
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− | **Stomatitis and otitis externa may develop
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− | *Microscopically:
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− | **Spongiotic neutrophilic pustular inflammation
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− | **Parakeratosis
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− | **Ulcerations
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− | **Superficial exudate containing organisms
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− | ==Cryptococcosis==
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− | *Over 19 species
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− | **''C. neoformans'' only major pathogen
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− | *Worldwide
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− | *Occurs in high concentrations in pigeon droppings (high creatinine concentration)
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− | **The pigeon is not infected
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− | **''C. neoformis'' colonise the droppings after they have been excreted
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− | **Also found in fruit, milk and soil
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− | *Exogenous, inhaled infection which is generally sporadic (non-contageous)
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− | **Can also be absorbed via skin penetration and ingestion
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− | *May be a primary pathogen or opportunistic
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− | *Targets the respiratory system
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− | **Including the paranasal sinuses
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− | **Also can be systemic, cutaneous, visceral, skeletal or ocular
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− | *Causes sporadic mastitis in cattle
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− | **Can spread within the herd
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− | *Affects the CNS of dogs and cats
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− | **Paranasal sinuses and pharynx can be infected with dissemination to the CNS and other tissues
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− | ***E.g. Lungs, kidneys and joints
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− | **Also causes subcutaneous granulomas
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− | **The tip of the nose is a common site of infection in cats
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− | *Causes myxoma-like lesions of the lung and lip in horses
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− | *Causes cryptococcal meningitis in humans
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− | *Also affects dolphins, foxes, ferrets, monkeys, birds, cheetahs and guinea-pigs
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− | *Large yeast with capsule seen using India ink stain
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− | *Stains with PAS (Periodic acis Schiff)
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− | *Gram positive
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− | *Grows on blood agar and Sabouraud's Dextrose agar forming white, granular colonies which become slimy, mucoid and turn cream/brown within a week
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− | *Species identified by carbohydrate assimilation tests
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− | *Antigen and antibody should be tested for as antibody formed by the body is soon overwhelmed and neutralised by abundent polysaccharide antigen from the capsule, in active, systemic infections
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− | **Latex agglutination for antigen, complement fixation, ELISA and IFAT can be used
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− | ==Geotrichosis==
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− | *''G. candidum''
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− | *Rare
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− | *Two forms: the yeast-like (glaborous) and fluffy
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− | *Affects a wide range of species
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− | *Usually diagnosed post-mortem
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− | *Affects the mucous membranes, udder, bronchi and lungs
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− | *Usually mild, causing suppurative granulomas
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− | *Can be recovered from otitis externa infections in dogs
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− | *Organisms appear as rectangular or spherical arthrospores on wet mounts
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− | **Thick walled, non-budding, gram positive
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− | *Grow on Sabouraud's Dextrose agar
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− | **Membranous colonies
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− | **Does not grow well on blood agar
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− | ==''Malassezia pachydermidis''==
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− | *Caused by [[Fungi|''Malassezia pachydermatis'']]
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− | *Normally present in oily areas on the external ear canal and skin in dogs
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− | **Some strains have been recovered from the ear canal of cats
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− | *Bottle-shaped, small budding cells, non-mycelial
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− | *Gram stain shows purple yeast cells with a very wide base
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− | *Grow on Sabouraud's Dextrose agar in 2 weeks of incubation at room temperature
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− | *Greenish discolouration on blood agar
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− | *Clinical disease may cause yeast to proliferate and cause infection
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− | *Grossly:
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− | **Regional lesions: muzzle, ears, interdigital, perianal
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− | **Or generalised disease
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− | **Erythematous, hyperpigmented, [[Skin Glossary - Pathology|lichenified]] and scaly lesions with alopecia
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− | *Microscopically:
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− | **[[Skin Glossary - Pathology|hyperkeratosis, parakeratosis]]
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− | **Spongiotic pustular dermatitis
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− | **[[Skin Glossary - Pathology|Acanthosis]]
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− | **Organisms are usually present, minimum 3-5 yeasts per high-power field must be found to imply cause of disease
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− | ==''Rhodotorula''==
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− | *''Rhodotorula minuta'' and ''R. rubra''
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− | *Canine ear infections
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− | *Equine uterus
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− | *Seldom seen in animal infections
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− | ==''Torulopsis glabrata''==
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− | *Commensal in animals and is found in the soil
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− | *Implicated in cases of:
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− | **Pyelonephritis, pneumonia, septicaemia and meningitis (humans)
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− | **Mastitis and abortion in cattle
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− | **Systemic infection of monkeys and dogs
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− | ==Trichosporonosis==
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− | *Found in soil
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− | *Deuteromycetes yeast
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− | *''Trichosporonosis beigelii''
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− | **Implicated in feline nasal granuloma, [[Mycotic skin infections - Pathology#Superficial mycoses|skin infections]] in horses and monkeys, mastitis in cattle and sheep and in feline bladder infections
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− | *''T. capitum'' implicated in bovine mastitis
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− | ==Further Links==
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− | *[[Mycotic skin infections - Pathology]]
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− | *''Cryptococcus neoformans'' causes granulomatous [[Nasal Cavity Inflammatory - Pathology#Infectious causes of rhinitis|rhinitis]] in cats, see [[Respiratory Fungal Infections - Pathology#In Cats|respiratory infections]]
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− | * ''Candida'' is an opportunistic pathogen at mucus membranes, causing thrush.
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− | *''Blastomyces dermatitidis'' in [[Respiratory Fungal Infections - Pathology#Blastomycosis|blastomycosis in lungs]]
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− | *''Histoplasma capsulatum'' in [[Respiratory Fungal Infections - Pathology#Histoplasmosis|histoplasmosis in lungs]]
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− | *''Candida'' spp. in [[Mycotic skin infections - Pathology#Candidiasis|candidiasis]]
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− | *''Malassezia pachydermis'' in [[Mycotic skin infections - Pathology#Malassezia dermatitis|malassezia dermatitis]]
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