Dermatology Test Questions - Canine & Feline Pruritis Flashcards

Question

Miliary Dermatitis - Diagnosis (8)

Answer 1

``` Skin scraping Acetate tape preparation Flea combing Wood's lamp examination Dermatophyte culture Parasiticidal therapeutic trial Dietary restriction-provocation trial Intradermal test, immunoglobulin E serum test ```

Answer 2

Bilaterally symmetrical alopecia Often localized to dorso-lumbar area and ventral abdomen, but can also affect limbs and flanks Head and neck spared Non-inflammatory (no other skin lesions)

Answer 3

Allergy (CAFR (Cutaneous adverse food reaction) > feline atopic dermatitis, FAD) Ectoparasitic infestation (e.g. Fleas) Dermatophytosis Psychogenic (psychological origin) Paraneoplastic Endocrinopathy (rare) Idiopathic

Answer 4

``` Skin scraping Acetate tape preparation Flea combing Wood`s lamp examination Dermatophyte culture Parasiticidal therapeutic trial Dietary restriction-provocation trial Intradermal test, immunoglobulin E serum test Dermatohistopathology (lack of dermal inflammation is not a good indicator of psychogenic alopecia) ```

Answer 5

Avoid using the name `Eosinophilic granuloma complex` clinically and histopathologically as it is an inconsitent mixture of clinical and histopathological terms The 2 different forms of this cutaneous pattern: (1. Papule/ plaque / nodule / edema 2. Ulcer) Have the same underlying causes Have a common histoptahological feature: an eosinophilic cell infiltrate in the dermis Can be observed in the same cat concurrently

Answer 6

1. Papule/ plaque / nodule / edema Variable pruritus and pain Papules or coalescing, firm, flat-topped erythematous and moist plaques, often localized to the ventral abdomen Linear, vertical and firm lesions seen on caudal thighs, more rarely on the neck, lateral thorax and thoracic limbs Firm nodule found in oral cavity (tongue, palate). May become ulcerated. May cause halitosis, partial anorexia, dysphagia and ptyalism Pododermatitis with ulcerated or edematous footpads and interdigital erythema Edema of lower lip or chin 2. Indolent ulcer Non-pruritic and painless Usually located on midline of upper lip or adjacent to canine upper teeth. May affect philtrum (between nose & upper lip) Often unilateral, sometimes bilateral Size varies from 2 mm - 5 cm, enlarges progressively

Answer 7

Allergy (Feline atopic dermatitis, CAFR, FAD) Ectoparasitic infestation Neoplasia (plaque = cutaneous lymphoma, mast cell tumor, mammary tumor metastases ; ulcer = squamous cell carcinoma) Viral, fungal and bacterial dermatosis Idiopathic

Answer 8

``` Skin scraping Acetate tape preparation Flea combing Parasiticidal therapeutic trial Dietary restriction-provocation trial Intradermal test, immunoglobulin E serum test Skin cytology Dermatohistopathology PCR (viral diseases) ```

Answer 9

Cat self-inflicts severe and spectacular lesions on the head and neck Very pruritic and striking in appearance Crusts, erosions, ulcers

Answer 10

Allergy (CAFR, feline atopic dermatitis, FAD) Ectoparasitic infestation Viral dermatosis (herpesvirus , calicivirus, FeLV; a history of sneezing, ocular or nasal discharge may aid in providing a clue) Néoplasia Idiopathic

Answer 11

``` Skin scraping Acetate tape preparation Flea combing Parasiticidal therapeutic trial Dietary restriction-provocation trial Intradermal test, immunoglobulin E serum test Skin cytology Dermatohistopathology PCR (viral diseases) ```

Answer 12

Large and thick crusts | Often localized to the face

Answer 13

Allergy (Feline atopic dermatitis, CAFR, FAD) Ectoparasictic infestation Dermatophytosis Auto-immune skin disease (Pemphigus foliaceus) Neoplasia

Answer 14

``` Skin scraping Acetate tape preparation Flea combing Wood`s lamp examination Dermatophyte culture Parasiticidal therapeutic trial Dietary restriction-provocation trial Intradermal test, immunoglobulin E serum test Skin cytology (look for acantholytic cells) Dermatohistopathology (look for acantholytic cells) ```

Answer 15

Scenario # 1 | Year-round pruritus • Atopic dermatitis (involved environmental allergens: house dust and storage mites, epidermals, moulds) • Atopic-like dermatitis • Cutaneous adverse food reaction • Non-seasonal ectoparasitic infestation (scabies, cheletiellosis, otoacariosis)

Answer 16

* Atopic dermatitis (involved environmental allergens: pollens) * Atopic-like dermatitis * Flea allergy dermatitis * Mosquito bite hypersensitivity * Warm weather seasonal ectoparasitic infestation (flea infestation, trombiculosis, Pelodera dermatitis)

Answer 17

* Atopic dermatitis (involved environmental allergens: house dust and storage mites, epidermals, moulds, pollens) * Atopic-like dermatitis * Cutaneous adverse food reaction * Flea allergy dermatitis * Ectoparasitic infestation

Answer 18

* Atopic dermatitis (involved environmental allergens: house dust and storage mites, epidermals, moulds) * Atopic-like dermatitis * Winter seasonal ectoparasitic infestation (pediculosis - body lice)

Answer 19

* Atopic dermatitis (involved environmental allergens: house dust and storage mites, epidermals, moulds, pollens) * Atopic-like dermatitis * Ectoparasitic infestation

Answer 20

* Atopic dermatitis (involved environmental allergens: ?) * Atopic-like dermatitis * Cutaneous adverse food reaction * Flea allergy dermatitis * Ectoparasitic infestation

Answer 21

* In any pruritic patient, the first intervention should consist of ruling out parasitic causes * Deep skin scrapings can rule out demodicosis * However, some mite infestations (e.g. Sarcoptes) might be missed on superficial skin scrapings, trichograms and acetate tape preparations * If a scabies is suspected, a parasiticidal therapeutic trial should be undertaken * Fleas can be ruled in or out on the basis of a history of flea control, response to flea control or finding evidence of flea infestation via flea combing * Flea control practices will also rule out louse infestations

Answer 22

Step 1 – Restriction 1. Slowly introduce restriction diet! • 1 meal of new food followed by 1 meal of old food • Both types of food at the same time 2. Restriction diet is to be fed exclusively! • No treats, rawhides • No flavored medications/toothpaste 3. Duration of trial: 6-10 weeks 4. If pruritus is decreased by at least 50% during this time, a diagnosis of adverse food reaction can be presumed

Answer 23

Step 2 – Provocation 1. Reintroduce previous food 2. If previous food contains offending allergen, pruritus should resume within 14 days 3. May be unacceptable to some pet owners 4. Does not differentiate between mechanisms of adverse food reaction (immunologic vs. non-immunologic adverse food reaction) but establishes a relationship between certain ingredients and observable clinical signs

Answer 24

Step 3 – Sequential provocation (optional) If pet owners want to identify exact offending allergen(s) 1. Feed restriction diet until pruritus resolves 2. Introduce 1 ingredient at a time for up to 14 days  Examples: Beef, chicken, lamb, fish, soybean, corn, wheat 3. Repeat sequence

Answer 25

Two types of environmental allergy tests are available: 1. The intradermal test (skin test, IDT) screens for the presence of allergen-specific immunoglobulin E bound to the surface of dermal mast cells and their ability to degranulate upon exposure to an allergen (visualization of immediate wheal-and- flare reaction, type I hypersensitivity) 2. The allergen-specific immunoglobulin E serum test (ASIST) screens for the presence of allergen-specific immunogobulin E circulating in the peripheral blood

Answer 26

Biological read-out (in-vivo test) Gold standard (measures allergic response in skin = target of allergic reaction) Quick results (15-25 minutes) Allergen tested can be individualized for patient and geographic location Use of positive (histamine), negative control (saline) Higher percentage of dogs produce meaningful positive reactions compared to ASIST More sensitive for Malassezia and flea saliva

Answer 27

Lesions are crusts in elbows, hocks and interface/margins of ears

Answer 28

Canine Atopic Dermatitis: a genetically predisposed inflammatory and pruritic allergic skin disease with characteristic clinical features associated with IgE antibodies most commonly directed against environmental allergens. - Percutaneous +++, Inhalation, ingestion, conjunctival Type I hypersensitivity reaction followed by a type IV hypersensitivity reaction Canine Adverse food reaction: reactions involving a clearly demonstrated humoral response mediated by immunoglobulin E Ingestion A type I followed by a type III, followed by type IV

Answer 29

Objective Easy to perform Simple blood draw No sedation, clipping Less effect of drugs No effect of stress Good alternative to IDT for veterinarian Who chooses not to refer patients Who does not perform IDT When pet owners decline referral When referral is impossible Good alternative to IDT when a patient cannot be skin tested (drug withdrawal times not respected, patient cannot be sedated for medical reasons, very small dog)

Answer 30

Sedation (issue with certain breeds) Clipping Healthy lateral thoracic skin Effect of drugs (glucocorticoids, antihistamines, must be withdrawn days to weeks in advance) Effect of stress (endogenous steroids) Skilled operator (subjective, effect of color- blindness) Lack of standardization Optimum concentrations are not validated Expensive for veterinarian (> 40 allergens, cost- effective if multiple tests are performed within kit shelf life) Suspect allergic patients may not react during peak of their allergic season (anergy, retest at more appropriate time?)

Answer 31

Extrapolation (in-vitro test) Presence and quantity of allergen-specific IgE do not correlate with severity of allergic disease Serum samples need to be sent out (2-3 weeks) No positive or negative control Limitations due to laboratories No interlaboratory standardization Results not always reproducible in same patient between different samples Variability of methods Lack of information about specificity of reagents Allergen tested are those offered by laboratory Interference from other antibodies (IgG) Arbitrary cut-off between positive an negative reaction Can be expensive for the owner Higher percentage of false positive reactions Patient may not have had recent exposure to allergen (retest at more appropriate time?)

Answer 32

Dorso-lumbar area, base of tail, medial & caudal thighs

Answer 33

Use the pinnal-pedal reflex Look for IgG serum antibodies Conduct an anti-parasitic trial & see if the clear it up

Answer 34

scales/flakes on dorsal body of young or immuno-compromised individual living in a dirty environment (skin scraping, tape, anti-parasitic trial)

Answer 35

1. Feline miliary dermatitis (FMD) 2. Feline symmetrical alopecia (FSA) 3. Feline eosinophilic dermatoses (ESD, ex-EGC) 4. Erosive/crusting dermatosis of head/neck (ECDHN) 5. Spontaneously occurring large crusts (SOLC)

Answer 36

atopic & atopic-like dermatitis are always on the table | add lice in winter, fleas & ectoparasites + mosquitoes in summer

Answer 37

1. Take away food gradually (alternate old/new) 2. Keep away for 6-10 weeks 3. If pruritis is decreased by 50% -> sign! 4. Re-introduce, possibly one ingredient at a time 5. see if after 14 days the pruritis is back

Answer 38

1. > 3 years 2. mostly indoor 3. corticosteroids makes it go away 4. originally no lesions 5. on pinnae of ears 6. not on margins of ears (scabies) 7. on front paws 8. not on dorso-lumbar area (fleas)

Answer 39

intra-dermal -> fast, gold standard, good results, may have to refer, remove drugs if on them, stressful, clipping etc IgE serum antibody --> cheaper, not as good results, may not need referral, less stressful

Answer 40

``` 3 allergic skin diseases 1. Canine atopic dermatitis (CAD) 2. Cutaneous adverse food reaction (CAFR) 3. Flea allergy dermatitis (FAD) parasitic skin diseases 4. Scabies 5. Cheletiellosis (mites) 6. Pediculosis (lice) ```

Dermatology Test Questions - Canine & Feline Pruritis Flashcards

(64 cards)