Dermatophytes, Candida albicans, Malassezia pachydermatis, Sporothrix schenckii Flashcards
Dermatophytes are what that infect what
Molds that infect keratinized epidermal structures
Dermatophytes disease is called what and what species cause it
Ring worm
Microsporum and Trichophyton
Dermatophytes Cause more severe disease in what
Younger animals
Dermatophyte transmission
Directly or indirectly from fomites or environment
Dermatophytsis pathogenesis
Arthrospore (arthroconidium) adheres to keratinized epithelium to enter stratum corneum and Germination occurs
A) Hyphae branch grows under skin and some of the growth will turn into arthroconidia as the hyphae contact the hair follicles
B). As hair shaft grows the arthroconidia form
C) Arthroconidia then invade hair shaft making hair brittle and will break
D) Arthrospores can disperse
Feline Dermatophytosis causative agent
Mycosporum canis
Feline Dermatophytosis Disease
Mild or asymptomatic in adults and lesions in kittens and infected kittens are very congageous
Also is zoonotic
Canine Dermatophytosis causative agent
Microsporum canis
Canine Dermatophytosis is common in what
Puppies
Bovine Dermatophytosis causative agent
Trichophyton verrucosum
Bovine Dermatophytosis disease spread and symptoms
Fomites spread and causes thick crusty lesions with alopecia
Commonly seen in crowded young cattle housed inside for extended periods
More of a cosmetic issue, lesions resolve when cattle are exposed to UV light
Poultry Dermatophytosis causative agent
Microsporum gallinae
Poultry Dermatophytosis is a what disease and where does it occur
Cosmetic disease in flocks with poor husbandry
Dermatophytosis diagnosis
Physical exam, exam hair under microscope, color change on DTM media, and **examine conidia produced on sporulation media
Are the Micro or Macroconidia seen in skin scrapings under a microscope with Dermatophytosis
No
Dermatophytosis treatment
Exposure to sunlight and dry conditions and topical anti-fungal treatments if needed
Can also do systemic antifungal treatment like Griseofulvin or Azole antifungals but neither are approved for food animals
Dermatophytosis Prevention
Clean and disinfect environment and fomites
No vaccine
Candida albicans is where
Normal Flora of GI, respiratory tracts, and genital tracts
How does Candida albicans grow
As budding yeast
What are the 2 growth forms of Candida albicans
Pseudohyphae (elongated yeast cells) and hyphae
Candida albicans types of Infections
Superficial and disseminated
Candida albicans Infections are associated with what
Allergy or immune deficiency or dysfunction
Candida albicans Disease
Candidiasis
Candida albicans Transmission
Endogenous, opportunistic pathogen
Candida albicans Disease is where usually
Usually where agent is normally located
Candida albicans Superinfections usually occur when
After antibiotics or poor sanitation in the same place the other infection was
Candida albicans systemic infection has
A poor prognosis
Candidiasis diagnosis
Microscopic examination, culture, PCR
How to treat candidiasis
Manage underlying immunosuppressive disorder and initiate antifungal therapy but resistance is a problem
Malassezia pachydermatis is what
A yeast, no hyphae formation
Malassezia pachydermatis transmission
Endogenous, normal flora
Malassezia pachydermatis pathogenesis
Alteration in the skin microclimate ex. Moisture, excessive sebum production
Malassezia pachydermatis Disease
Otitis external or dermatitis (folded skin)
Malassezia pachydermatis Diagnosis
Peanut shaped organisms via cytology or culture
Malassezia pachydermatis Treatment
Antifungals
Sporothrix schenckii complex is what type of fungus
Dimorphic- mold form in soil or media and yeast in hosts
Sporothrix schenckii complex Is seen where
In warmer regions on hay, rose thorns, soil
Sporothrix schenckii pathogenesis
Implanted into skin via cut and then mold form changes to yeast which are them phagocytosed by macrophages and then the yeast can hitch a ride to the lymph nodes and be spread in lymphatics. Overlying skin may ulcerate
Sporothrix schenckii disease and in what
Sporotrichosis- can be in many species but most severe in cats, causes skin ulcers and can disseminate through lymphatics sometimes spreading to lungs or liver
Sporotrichosis Diagnosis
Biopsy looking for cigar-shaped yeast
Sporotrichosis Treatment
Antifungals and continue treating 1 month after lesions disappear
Sporotrichosis Zoonosis?
Yes, wear gloves and wash hands
Avian candidiasis affects what and is related to what
young poultry usually as a result stress from poor sanitation or over crowding
