Derm Flashcards

1
Q

What species does pemphigus foliaceus affect?

A

goats

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What type of hypersensitivity occurs in pemphigus foliaceus?

A

Type II

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Where are the lesions in pemphigus foliaceus?

A

face, limbs, abdomen, perineum and scrotum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the proposed mechanism for the pathophys of pemphigus foliaceus?

A

Autoantibodies directed against the glycocalyx or keratinocytes leads to loss of intracellular cohesiveness and blister formation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Dx of pemphigus foliaceus

A

biopsy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Trt for pemphigus foliaceus

A

prednisolone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Prognosis of pemphigus foliaceus

A

Unknown - not enough cases documented to adequately comment.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

synonym for urticaria

A

wheels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

definition of urticaria

A

transient focal swelling of the skin +/- mucous membranes representing localized areas of dermal edema.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

common immune mediated mechanism of urticaria

A

reactions to allergens such as drugs or ingested/inhaled allergens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Treatment of urticaria

A

avoid the allergen and give corticosteroids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

urticaria is one of the main manifestations of:

A

milk allergies in dairy cows

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the most common type of contact dermatitis?

A

irritant- most of the time iatrogenic due to bedding, wood, medications etc…

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

causative agent of dermatophiliosis

A

dermatophilus conglensis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

etiology of dermatophiliosis

A

G+ aerobic sporulating bacteria with branching filamentous ‘railroad tracks” growth pattern

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

synonyms for dermatophilosis:

A

curaneous streptothricosis (cattle/goats), rain scald (equine), lumpy wool, mycotic dermatitis (misnormer in sheep); strawberry footrot (sheep);

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Is dermatophiliosis zoonotic?

A

YES!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the risk factors for dermatophilosis?

A

Humid weather (warm/cool)

prolonged rainy season

frequent spraying/dipping

crowding

breed (Merino sheep)

High fly/tick populations

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Pathophys of dermatophilosis:

A

skin becomes soft and comprimised by excessive moisture –> motile zoospores germinate in the defect in the stratum corneum –> mycelium proliferate in living areas of the epidermis and cause initiation of neutrophilic inflammatory response –> response prvents local spread of the organism –> organism sheds in serocellular crusts with reepithelialization;

Healing requires cell mediated and humoral immune responses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the source of infection of dermatophilosis?

A

suspected to be from the soil but hasn’t officially been isolated from soil

fairly ubiquitous and survives in the environment (spores)

Chronic carrier animals tend to be a problem

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

clinical signs of dermatophilosis

A

proliferative suppurative crusts, matted hair, “paintbrush” appearance, pink to grey moist, PAINFUL granulation bed like lesions;

***Painful NOT pruritic!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

How do you diagnose dermatophilosis?

A

Impression smear of the lesion under the crust and stain it to look for the railroad like morphology– scraping can disrupt this!

Biopsy

There are also ELISA tests and you could do culture but it requires special techniques

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Treatment for dermatophilosis:

A

remove the predisposing factors/insult

dry out

bathing with pivodine iodine shampoos when appropriate for the operation.

topical cholorhexadine solutions

Systemic antimicrobials if severe and generalized

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Define folliculitis

A

inflammation of hair follicles secondary to bacterial infection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Define impetigo
Less severe inflammation of epidermis NOT involving the hair follicles.
26
Define furunculosis
more severe inflammation involving rupture of follicles and subsequent infection of surrounding dermis and subQ tissues.
27
What species is folliculitis/furunculosis/impetigo occur in and what typically causes it?
Goats - caused by coag + staph spp. (S. aureus and S. pseudintermedius)
28
Where on the body will you observe folliculitis/furunculosis/impetigo lesions?
on the udder, abdomen, thigh and perineum Painful not really pruritic lesions
29
Papillomatous digital dermatitis = ?
``` hairy heel warts foot warts heel warts Mortellaro's dz Strawberry heel warts ```
30
Define papillomatous digital dermatitis
infectous/contagious dermatitis of the digital skin of cattle
31
Do hairy heal warts occur more in dairy or beef cattle?
Dairy **key cause of lameness in dairy cattle!
32
Do hairy heel warts occur more in hind or front feet?
Hind (80%) proximal to heel bulb and extending into the interdigital space
33
describe the lesion seen with hairy heel warts
raised, circular to oval, discrete demarcation, with filiform papillae on the lesion and hairs 2-3X the normal length surrounding, VERY PAINFUL +/- foul odor!
34
What are your DfDx for hairy heel warts?
foot rot corns (interdigitial fibroma) interdigital dermatitis
35
What is the posterchild cow to get hairy heal warts and why?
1st or 2nd lactation shortly after lactation because the cow is immunocomprimised during this period due to increased energy demands and colostrum synthesis
36
What are the risk factors for hairy heel warts?
muddy wet conditions (low O2 tension) introduciton of carrier replacement animals
37
What is the most common organism found in hairy heel warts
treponema spp. typically the pathogenesis is multifactorial including environmental, microbial, host, and mangagement factors
38
Treatment/prevention for hairy heel warts
topical antibiotics (none are labeled - be aware of extra-label drug use) Footbaths are effective (lincomycin, oxytet, formalin, coppersulfate, zinc sulfate) Improve stall/alley hygiene reduce stocking rate improve ventilation to aid in drying disinfect foot trimming equipment
39
define papillomatosis
warts or fibropapillomas (occurs in cattle, goats, and sheep (primarily young))
40
What causes fibropapillomas?
Viral! There are at least 6 bovine papilloma viruses; Goats have their own papilloma viruses this is rare in sheep! *animals that become overwhelmed with these lesions are thought to have abnormalities in cellular immunity.
41
TRT for warts
crush/pinch off/surically excise/ cryosurgery There are also vaccines available - both commercial and autogenous
42
Define Dermatophytosis
Ringworm/ dermatomycosis (infection of the keratinized layers of epidermis, hair, nails, hoof, and horns)
43
What is the causative agent of ringworm?
Trichophyton primarily seen in ruminants; transmitted via direct contact between animals or via fomites (lives in organic material like wood and bedding so the enviromnent can become contaminated for years)
44
What are some risk factors for development of ringworm?
``` young age high stocking rate group/indoor housing poor nutrition comorbidities high humidity/temperatures carrier animals ```
45
Clinical signs of ringworm
alopecia, scaling, crusting, +/- pruritis lesions are multifocal, variable in size, and have minimal inflammation
46
Diagnosis of ringworm
clinical signs, microscopic exam of hair around edge of lesion, culture on DTM
47
Treatment of ringworm
typically self limiting and spontaneously regresses can treat individuals with iodine ointments, miconazole shampoos, griseofulvin, in groups - can mix Captan in water and spray animals 1X weekly for 2 weeks; can also mix and spray on housing material and equipment to prevent reinfection
48
define pediculosis
infestation with lice
49
how are lice maintained in the animal population
on carrier animals
50
Clinical signs of pediculosis
PURITIS, dry/scaly skin, patchy alopecia, anemia if the infection is heavy with sucking lice, phytobezoars and weight loss
51
Treatment for pediculosis
Ivermectin (for sucking lice) Powder rubbed deeply into the hair for chewing
52
Define Acariasis
mite infestation
53
4 types of mites that infect ag animals are:
Psoroptic Chorioptic Sarcoptic Demodectic
54
Which mites are reportable?
Psoroptic in cattle in the USA Sarcoptic Demodectic and chorioptic in some states
55
What mite species is zoonotic?
sarcoptic
56
What is the key clinical sign in psoroptic, chorioptic, and sarcoptic mange?
PRURITIS!!
57
Where are the lesions in psoroptic mange?
epithelial surface, crusty, papular lesions on the withers, head and ears
58
Where are the lesions in chorioptic mange?
"Foot and leg mange" alopecia, scaling, crusting on the lower limbs and perineum, tail/tailfold
59
Where are the lesions in sarcoptic mange?
scaling, cursting, alopecia, and self trauma seen with the head, neck, and ears commonly affected. (can be generalized)
60
What are the lesions like in demodectic mange?
zit like in goats - completely filled with mites; nodular lesions typically on the head, neck, and shoulder in cattle/goats;
61
What is the treatment for acariasis?
ivermectin (effective in all species) Amitraz for demodex or it may spontaneously regress.
62
What is stephanofilariasis?
filarial dermatitis transmitted by the female horn fly when she feeds on the ventral midline of cattle; see ventral midline dermatitis which progresses to nodules and alopecia - not typically treated.
63
What are 3 types of photosensitizaton?
Primary - circulating photodynamic agents that are activated by UV light and emit energy damaging tisues; Secondary which there is an initial insult that damages the liver previenting it from conjugating phylloerythrin which then acts as a photodynamic agent; Phylloerythrin is a normal byproduct from the degradation of chlorophyl. Congenital; in which there are aberrant pigments being synthesized in the body (rare)
64
What are some plants that can cause primary photosensitization?
``` ST. JOHN'S WORT buckwheat (fagopyrum) wild carrot (daucus) perennial rye grass (lolium) burr trefoil (medicago) Lady's thumb ```
65
What are some drugs that can cause primary photosensetization
sulfonamides tetracyclines phenothiazine thiazides
66
Treatmetn of photosensetization
``` Remove photo agent source avoid sunlight -provide shade source Abx if you have a secondary pyoderma Wound management symptomatic trt for liver disease. ```
67
What is the prognosis for the types of photosensetization?
Primary - favorable Secondary (hepatogenous) - poor Congenital (porphyra) - poor
68
What are other names for contagious ecthyma?
Orf | Sore mouth
69
What causes orf?
poxvirus - subgroup parapoxvirus
70
Is orf zoonotic/reportable?
YES! and YES!
71
What are some risk factors for developing orf?
dry seasons access to wild ruminants surgical procedures Failure of passive transfer (for malignant form)
72
Where do orf lesions tend to occur on the body?
on the mucous membranes - around the nose, lips, gingiva, udder, and heel bulbs, lungs, trachea, and esophagus etc.. in the malignant form
73
How is orf transmitted?
via contact with infected animals, surfaces, or environments! highly contagious with high morbidity rates; and the pox virus is stable in the environment for up to 12 years!
74
describe the clinical progresion of orf
lesions are papular --> vesicular --> pustular --> proliferative, coalescing, and scabbed they are painful and tend to spontaneously regress in 2-3 weeks Lambs with lesions on their muzzel and dams with lesions on their udder will be reluctant to participate in nursing.
75
How do you diagnose orf?
Hx, clinical signs, serology +/- viral ID via culture or EM;
76
What are some DfDx for orf?
sheep pox/goat pox -- these are more virulent and cause pyrexia/rhinitis Bluetongue - mostly mouth lesions and is seasonal for the fall while orf tends to occur in the spring Ulcerative dermatosis
77
What is the treatment for orf?
supportive - tube feeding etc. Do NOT debride the lesions - can do intralesional steroids and prevent secondary bacterial infections
78
How do you control orf?
isolate early cases and try not to contaminate the environment vaccination is an iption but it is ineffective if the incidence is already high as well as via ewe vaccination -- if your going to do it giving autogneous vaccines to 6-8 week old lambs is most effective