Highly contagious, can affect any cat (Usually more than one cat affected in household)
Does Notoedres cati cause pruritus?
Can cause intense pruritus (Hypersensitivity reaction)
how does notoedres cati mange live on the body?
Female mite burrows into skin, then lays eggs (Can transiently infest dogs, people)
where does Notoedres cati live geographically?
Very uncommon in N. America, common in Australia, certain parts of Europe
clinical signs of a notoedres cati infection? distribution of CS?
Intense pruritus (9-10/10) which Typically affects head and pinnae (If chronic, entire body and feet). Also see Crusting, scaling, erythema, alopecia, 2o self-trauma, “seizure”. In severe cases, peripheral lymphadenopathy, anorexia, emaciation, death
will you see systemic signs with notoedric mange?
In severe cases, peripheral lymphadenopathy, anorexia, emaciation, death
what are the two ways to dx notoedric mange?
(1) Superficial skin scrapings (2) Response to treatment (i.e. if history is suspicious, do empirical acaricidal therapy)
is notoedric mange a deep or superficial skin scrape?
SUPERFICIAL (they burrow in skin like scabies)
what Acaricidal Therapy do you use for tx notoedric mange?
Selamectin or moxidectin! (q 2 weeks, 3 times). Can also try: Ivermectin, 2% lime sulfur, Amitraz. Treat all in-contact mammals!
(1) Superficial skin scrapings (Non-affected cats should also be scraped- if you can't find them on the itchy affected cat, you might be able to find them on a clinically unaffected cat) (2) Acetate tape test (3) Fecal floats* (might ingest them when grooming) (4) Empirical treatment and response to lime sulfur dips
deep or superficial scrape for feline demodicosis?
SUPERFICIAL!!! these guys live superficially unlike the dog ones!!
what are two treatments for feline demodicosis?
(1) Lime sulfur dips (2-4%) (1-2 times per week for 2 months) (2) Amitraz dips (Anorexia, lethargy, diarrhea)
which type of demodex can resolve spontaneously in cats?
D. cati can resolve spontaneously if underlying disease is addressed (bc normal commensal that just gets out of control due to immunosuppression)
Superficial fungal infection of hair shafts and stratum corneum. Proteolytic / keratolytic enzymes allow keratin to be used as nutrition
how are dermatophytes transmitted?
Transmission by direct-indirect contact
what are the 3 species of dermatophytes which affect cats? which is the most common one in cats?
Microsporum canis (zoophilic) (*most common- 98% of the time. common but should not be considered a normal flora), Microsporum gypseum (geophilic), Trichophyton mentagrophytes (zoophilic)
what 3 populations of cats are esp sensitive to dermatophytes?
(1) Young , immunocompromised (2) Cats with skin trauma (Pruritus, playing / fighting, ectoparasites, clipping, Poor hygiene, "social stress" (3) Asymptomatic (subclinical) carriers (Long-haired cats, Persians)
Which cats tend to be asymptomatic carriers of dermatophytes?
Long-haired cats, Persians
what are the clinical signs of dermatophytosis?
(Many different presentations!) Circular areas of alopecia with erythematous border, Transient follicular pustules, Miliary dermatitis, Scale/crusts absent to severe, Rarely, dermal nodules (pseudomycetoma), Pruritus variable
what is a pseudomycetoma?
dermal nodules, rarely a clinical sign of dermatophytosis
5 ways to dx dermatophytes?
(1) Wood’s lamp examination (****REMEMBER: Only 50% of M.canis will fluoresce) (2) Trichogram (3) Dermatophyte PCR (4) Fungal culture and ID (Sabouraud’s agar) (5) Biopsy + special stains (PAS)
which stain would you stain a dermatophyte bx with?
*woods lamp only works when?
Only 50% of M.canis will fluoresce!
easy way to collect sample for culture?
brush cheap toothbrush over lesions and over non-lesioned areas, dip toothbrush in culture medium, send it away
what is the culture medium you use to grow dermatophytes? what is in the culture medium?
(can be plain Sabouraud’s agar also) Dermatophyte test medium (DTM) which contains Antibiotics (Gentamicin, chlortetracycline), Cycloheximide, Phenol red, Carbohydrate and protein nutrients
how does DMT medium encourage dermatophytes to grow, as opposed to saprophytes which are just around and in the air? What is a color change which helps indicate growth?
Dermatophytes use protein as energy first vs. saprophytes which use carbs. DMT has protein nutrients in it. Also, DTM changes from yellow to red due to production of alkaline by-products
what are you looking for with the DMT culture for your dermatophytes? (3 things you do)
(1) Check sample daily to observe yellow to red colour change (2) Assess growth colony macroscopically (White, buff, tan) (3) Assess growth colony microscopically (more on this in diff card)
what colors of colonies are you looking for when culturing dermatophytes on DMT?
white buff and tan
how do you Assess growth colony microscopically (how do you get a sample? what stain? what should Macroconidia of M. canis look like?)
use tape to gather a sample from the growth medium, and stain with blue modified Wright’s stain (Diff quik #3). Macroconidia of M. canis should have >6 cells with thick cell walls and knobs on their ends
what are the Principles of Treatment for dermatophytes? (4) (when can you stop treating is one of them)
(1) Identify all affected animals/subclinical carriers (2) Quarantine all affected (3) Treat until 2 consecutive negative fungal cultures, 2 weeks apart (4) Environmental decontamination
how do you know when to stop tx for dermatophytes?
Treat until 2 consecutive negative fungal cultures, 2 weeks apart
what are 4 options for topical therapy for dermatophytes?
Lime sulfur dips, Enilconazole spray, Miconazole 2% shampoo, Terbinafine cream (Lamisil®) (Not always effective as sole therapy)
what should you warn owners about lime sulfur dips as a topical tx for dermatophytes?
Will stain white cats, Smells awful, Remove silver jewelry or it will be tarnished
what are three options for systemic tx of dermatophytes? what should you NOT USE for tx cats with dermatophytes?
CAN USE: Itraconazole/fluconazole 7-10mg/kg/day PO with food. OR Terbinafine 40mg/kg PO q 24h. DO NOT USE: Cats do not tolerate ketoconazole~ --> GI upset, hepatotoxicosis
4 things you can do to help reduce environmental contamination of dermatophytes?
(1) Daily cleaning with dilute bleach 1:10 for all hard surfaces (2) Change air filters (3) Throw away anything that may harbour spores (4) Steam clean carpets, drapes, wash bedding