Skin and Wound I

Question 1

treponema spp. general characteristics

Answer 1

• spirochete
• gram neg staining not true gram neg(w/ 2 membrenes outer no lps; have cell wall)
• flagella in periplasmic space
• anaerobes

Question 2

treponema spp. found where

Answer 2

• environement
• mucosal surfaces and digestive tract
• feet of infected animals

Question 3

treponema spp. spread how

Answer 3

• direct contact
• indirect contact
• effected when we underwood especially in fecally contaminated environment (bacteria from digestive tract into environment)

Question 4

treponema spp. cause what

Answer 4

• bovine digital dermatitis “hairy foot” “hell wart”

Question 5

treponema spp. see what

Answer 5

• ulcerative or proliferative lesions along coronary band typically affects hind feet
• lameness

Question 6

treponema spp. affects who

Answer 6

diary cows > beef

Question 7

treponema geography

Answer 7

in Europe more ulcerative lesions

in us more granulomatous/ proliferative type lesions

Question 8

skin lesions can be spread to feet when its wet underfoot why

Answer 8

When wet underfoot -> masceration of skin -> tight juncitons between cells dec so this can get in

Question 9

fusobacterium necrophorum general characteristics

Answer 9

• gram neg
• bacilli or fillamenous
• obligate anerobes

Question 10

fusobacerium necrophorum natural inhabitation of

Answer 10

mucous membranes

Question 11

fusobacteirum necrophorum spread how

Answer 11

• persistent soaking on wet pastures (breaks in skin make animal susceptible to foot infections)

Question 12

fusobacterium necrophorum causes what in who

Answer 12

• affects cows -> interdigital dermatitis (foot rot) (not for this week but also causes calf diphtheria in GI tract)
• horses -> thrush (same kind of dx as cows diff name)
• foot dx small ruminants

Question 13

fusobacteirum necrophorum see what in cows

Answer 13

• fissures in interdigital space
• foul smelling
• lameness
• starts btwn digits often stays there
• usually just one foot on animal effected, often mult animals in same environment effected at once

Question 14

testing trephanimes

Answer 14

• pcr for trephanimes (usually dont test organism in foot dx)

Question 15

testing for fusobacterium necrophorum

Answer 15

• culture and grow acerbically (usually dont test organism in foot dx)

Question 16

tx bovine foot dxs (treponema and fusobacteirum necrophoru)

Answer 16

• trim hooves
• antibiotics (topical, foot bath)
• improve hygine
• fence wet areas

Question 17

causative agents foot dx in small ruminants

Answer 17

• dichelobacter nodosus
• fusobacteirum necorphorum
• fusobacteirum necrophorum starts things off causing damage to interdigital epidermis persistent soaking on wet pasture then dichelobacter nodosus comes in -> damage

Question 18

dichelobacter nodosus general characteristics

Answer 18

• gram neg
• obligate anaerobe
• bacillus
• swelling at end of bacilli can be helpful to ID

Question 19

dichelobacter nodosus causes what in who

Answer 19

• footrot in small rumiants (interdigital swelling then invasion of epidermal structures)

Question 20

dichelobacter nodosus see what

Answer 20

• lamness (loss of hoof sole)

- foul smelling lesions

Question 21

foot rot in small ruminants diagonsis

Answer 21

• clinical presentation

- gram neg rods in exudates (dichelobacter nodosus)

Question 22

foot rot small ruminants tx

Answer 22

• removal and exposure and diseased tissues (expose to o2)
• topical disinfectants or antibiotics
• ideally catch when early (just fusobacterium necrophorum) and segregate infected from non infected
• vac w/ bacteria helpful not totally preventable though

Question 23

dermatophyte infections include

Answer 23

• ringworm
• tinea
• dermatophytosis

Question 24

dermatophytes of interst

Answer 24

• trichophyton spp.
• microsporum spp.
• both in asexual forms

Question 25

dermatophyte general characteristics

Answer 25

- obligate anaerobes - macroconidia, microconidia formed off aerial hyphae in free living form (diff candid depending on where formed) - arthrocondida in parasitic form - ZOONOTIC

Question 26

dermatophyte found where

Answer 26

- geophillic (soil) - zoophlic - antrhophillic (ppl) - dnt like temps > 35 degrees c so keeps lesions superficial

Question 27

dermatophyte spread how

Answer 27

direct and indirect contact

Question 28

dermatophytes cause what broadly and how

Answer 28

fungal skin dxs by making keritinases so can live in keratinized tissues

Question 29

ringworm see what

Answer 29

- erythema or vesicles or pustules - usually circular lesions bc fungi move out radially from initial inoculation site; active fungal growth at edge of rings (this is also where host response to fungi is) - alopecia with scaling or crusting - self limiting - generally infection in younger animals - generally not pyritic (animal not itchy)

Question 30

dermatophytoses pathogenicity

Answer 30

- conidia germinate in host after entering via breaks in stratum corneum mycelium grow along cornfield epithelium and w/ in hair - grow in to hyphae after time hyphae differentiate into arthrocondida (repro form) which can be spread - produce keritinase and other proteases allowing them to colonize keratinized tissues - inflam response to fungi radiating form site of inoculation -> ring shaped lesion

Question 31

dermatophytoses lesions

Answer 31

- lesions often circular

Question 32

diagnosis of dermatophytoses

Answer 32

- woods lamp for Microsprum canis (doesn't tell you for sure that its ring worm) - examine hair/ scales in mineral oil - tx hair/ scales w/ Koh for hyphae and arthrocondida - fungal culture (dermatophyte test medium for up to 3 weeks, characteric macroconidia)

Question 33

dermatophyte test medium works how

Answer 33

- 10 days see saprophytes (change color of media) | - dermatophytes grow slow so see slower change color or media

Question 34

differentiation dermatophytes

Answer 34

- macrocondida from microsporum spp. and trichophyton spp. look v different so can tease off areas where there are hyphae and look at these in culture under microscope - rRNA sequencing

Question 35

tx dermatophytes

Answer 35

- topical antifingals - systemic tx - these are self limited but v contagious which = why treat - vac for trichophyton verrucosum but not really used in us but yes used in Europe

Question 36

staphylococcus pseudintermedius general characteristics

Answer 36

- gram pos - fac an - coccus - clusters

Question 37

staphylococcus pseudintermedis infections general

Answer 37

- primarily superficial | - humans can be transiently colonized w/this one but this is primarily in animals

Question 38

staphylococcus pseudintermedius natural inhabitatng

Answer 38

mucusouls membranes of skin

Question 39

staphylococcus pseudintermedius infeciton predisposing factors

Answer 39

- endogenous infection - skin dx - (normal flora overgrows -> staph infection)

Question 40

staphylococcus psuedointermedius causes what in who

Answer 40

- pyoderma usually in dogs | - rarely also in cats

Question 41

staphylococcus pseudintermedius usually see what

Answer 41

- papular lesions initially then pustules then folliculitis - often also allopecia - lesions usually start in moist areas (neck areas)

Question 42

staphylococcus pseudintemedius outcome determinents

Answer 42

- host factors = key determinant | - confection w/ normal commensals of skin = possible

Question 43

staphylococcus pseudintermedius diagonsis

Answer 43

- skin scarping - direct impression smear (gram pos cocci in large numbers = indicative of this ) - culture if evidence mixed infection or if tx fails ot resolve signs in 6 weeks

Question 44

staphylococcus pseudintermdis tx

Answer 44

- systemic ab therapy w/ topical ab shampoos - bc pt of normal commensal point is to prevent underlying dx or whatever is -> overgrowth not get rid of this completely