Module 2 MiniModule 1: Pruritus - Introduction, Approach, and Feline Pruritus Flashcards
Mediators of pruritus:
Histamine, serotonin, platelet-activating factor
Vaso-active amines
Mediators of pruritus:
Prostaglandin, leukotrienes
Eicosanoids
Mediators of pruritus:
Cathepsin, trypsin, fibrinolysin
Proteases
Mediators of pruritus:
Neuropeptides, bradykinin
Peptides
Mediators of pruritus:
IL-31
Cytokines
Role of Cutaneous Neurons in Skin:
Mediators of pruritus are released in close proximity to what nerves?
Primary Afferent Nerves
Role of Cutaneous Neurons in Skin: Fill in the blanks
The signals travel along nerve fibers, received by the _____(1)____ root ganglia and the _____(2)____ horn of the spinal cord to the brain
- Dorsal
- Dorsal
Puritus:
What is the threshold phenomenon and summation effect?
Allergic animals can tolerate certain degrees of stimuli that are involved in their pruritus, but each one has a variable threshold
Hypersensitivities defined:
A pruritic skin disease that is a result of IgE-mediated hypersensitivity to environmental allergens
Atopic Dermatitis (AD)
Hypersensitivities defined:
- Food allergy
- Immunologically mediated adverse response to food
- Food intolerance
- Abnormal physiologic response to a food
- Toxic, pharmacologic, metabolic
Cutaneous adverse food reactions (CAFR)
List the most common causes of pruritis:
- Allergic disease
- FAD, CAFR, AD
- Infections
- Pyoderma, Malassezia (yeast) dermatitis
- Parasites
- Sarcoptes, Notoedres
- Demodex gatoi
- Cheyletiella
Seasonality:
Relating to or characteristic of a particular season of the year
Seasonal
Seasonality:
No varying with the seasons; constant, permanent
Nonseasonal
Seasonality:
Year-round itching, but at certain times during the year the pruritus escalates
“Seasonally nonseasonal”
- Flea allergy dermatitis
- Atopic dermatitis
- Insect hypersensitivity
What seasonality are these?
Seasonal -> Nonseasonal
- Cutaneous adverse food reaction
- Sarcoptic mange
- Infections
What seasonality are these?
Nonseasonal
- these are strictly nonseasonal
(T/F) The clinician rates the pruritus of the animal
False, the owner rates the pruritus (scale of 1-10). Reference point needed to monitor changes.
List the disease with the most intense pruritus:
- Sarcoptic mange
- Flea allergy dermatitis
- CAFR
Age of Onset:
Ectoparasites, FAD, CAFR
< 6 months old
Age of Onset:
Atopic Dermatitis/CAFR
1 to 3 years of age
Age of Onset:
CAFR
> 7 years of age
List some human/animal pruritus:
- Sarcoptic mange, Notoedres
- Dermatophytosis +/- (it can be pruritic but sometimes it isn’t)
- Demodex gatoi (only cat to cat)
Diagnostic procedures:
- Demodicosis
Deep skin scraping
Diagnostic procedures:
- Sarcoptes, Cheyletiella, Notoedres
Superficial skin scraping
Diagnostic procedures:
- Bacteria, yeast
Surface cytology
Diagnostic procedures:
Fleas, flea feces
Flea comb
List some cat skin lesions differences:
- Non-inflammatory alopecia, miliary dermatitis, eosinophilic granuloma complex
- Rare excoriations, lichenification, hyperpigmentation
You identify 10-20 yeast organisms/oil immersion field microscopically from the paws. You want to prescribe a topical product for the owner to use daily on the paws. What active ingredient should the topical product contain?
- Miconazole
- Climbazole
(Azoles are a god choice for topical therapy for yeast)
If you are unsure if a cat is pruritic and the cat has hair loss, what diagnostic test should be performed?
Trichogram
- If the tips of the hairs are blunted, the cat is pruritic; if the tips are pointed, the hairs are falling out and the cat is not pruritic
The least common cause of feline self-induced feline symmetric alopecia is:
Psychogenic
If a cat is pruritic in the “pants” region, what is the most likely cause?
- FAD
- CAFR
- FASS
List skin lesions that are less common to see on a cat:
- Excoriations, lichenification, hyperpigmentation
- Secondary infections, OE
Definition:
- Papulocrustous cutaneous reaction pattern
- NOT an etiologic diagnosis
- Common
- Secondary alopecia, erythema, excoriation
- Localized or generalized
Miliary Dermatitis
Eosinophilic Granuloma Complex:
- Upper lip
- Well-circumscribed
- Disc-shaped
- Uni- or Bilateral
Indolent Ulcer
Eosinophilic Granuloma Complex:
- Linear granuloma
- Pharyngeal granuloma
- Chin/lip form
- Pawpad
Collagenolytic Granuloma
Eosinophilic Granuloma Complex:
- Raised lesion
- Can be anywhere, but mostly seen in the ventral abdomen
Eosinophilic Plaque
Eosinophilic Granuloma Complex:
- Mimics dogs
- Very severe
- Multiple crusts on the lesion
- Mimics autoimmune disease
Head and neck pruritus
Non-Self-Induced Alopecia (Rare):
Endocrine
- Hyperthyroidism
- Diabetes mellitus
- Hyperadrenocorticism (skin tear)
Non-Self-Induced Alopecia (Rare):
Paraneoplastic
- Shinny
- Feline paraneoplastic alopecia
- Pancreatic AC
- Biliary carcinoma
