Derm3- Keratinization

  1. Defect in the keratinizing epithelium or glandular function, usually due to hereditary causes or breed predilections.
    primary disorders of keratinization
  2. The major of keratinization disorders are ______________.
    secondary to another dermatosis
  3. What are PE findings with keratinization disorders? (7)
    dry, waxy, or greasy scaling, comedones, follicular casts, alopecia, inflammation, crusts, pruritus
  4. How do you diagnose a primary keratinization defect?
    rule out all potential causes of secondary scaling disorders!!!
  5. What are pruritic causes of secondary scale? (7)
    FAD, atopic dermatitis, CAFR, sarcoptic mange, Cheyletiella, pyoderma, Malassezia
  6. What are non-pruritic causes of secondary scale? (9)
    demodex, dermatophytosis, hypothyroidism, cushings, alopecia X, metabolic diseases, autoimmune diseases (pemphigus), pyoderma/ yeast (usually pruritic but always rule out, even in the absence of pruritus), neoplastic
  7. What are the most common canine primary keratinization disorders? (4)
    zinc-responsive dermatosis, sebaceous adenitis/granulomatous periadnexal dermatitis, canine acne, canine ichthyosis
  8. What are the syndromes associated with zinc-responsive dermatoses?
    • Syndrome I- huskies, malamutes, bull terriers; genetic; occurs at 1-3 years of age
    • Syndrome II- less common; associated with an inappropriate diet
  9. What are clinical signs of zinc-responsive dermatosis syndrome I? (6)
    • scaling, crusting, alopecia, erythema, hyperkeratotic footpads, pruritus¬†
    • [mouth, chin, eyes, ears, scrotum, vulva, prepuce, elbows]
  10. What are the usual locations of zinc-responsive dermatosis syndrome I? (9)
    mouth, chin, eyes, ears, scrotum, vulva, prepuce, elbows, hyperkeratotic footpads
  11. What breeds are associated with zinc-responsive dermatosis syndrome I? (3)
    huskies, malamutes, bull terriers
  12. How do you diagnose zinc-responsive dermatosis syndrome I? (4)
    history, PE, rule out diseases that cause secondary scale, biopsy (suggestive)
  13. What will you likely see on biopsy of a dog with zinc-responsive dermatosis syndrome I?
    marked diffuse epidermal and follicular parakeratotic hyperkeratosis (no nuclei)
  14. How do you manage zinc-responsive dermatosis syndrome I? (5)
    oral zinc supplementation (dose split b/w BID), low dose glucocorticoids, fatty acid supplementation, treat secondary infections, keratolytic shampoos
  15. An inflammatory disease directed against the sebaceous glands.
    sebaceous adenitis
  16. What is the cause and pathogenesis of sebaceous adenitis?
    cornification abnormality that causes obstruction of sebaceous ducts and inflammation of the glands
  17. What age and breed of dog is usually affected by sebaceous adenitis? (4 breeds)
    young to middle-aged; standard poodle, akita, samoyed, belgian sheepdog
  18. What are clinical signs of sebaceous adenitis? (5)
    bilaterally symmetrical alopecia, scaling, dull brittle hairs, may progress to generalized dermatosis with tightly adherent scales and matted tufts of hair
  19. Where on the body does sebaceous adenitis usually begin? (5)
    dorsal surfaces (head, cervical, pinnae, face), may progress to generalized
  20. How do you diagnose sebaceous adenitis? (3)
    history/PE, rule out causes of secondary scaling, biopsy
  21. What do you see on biopsy of a dog with sebaceous adenitis? (2)
    granulomatous inflammation at the level of the sebaceous glands, absence of sebaceous glands in advanced disease
  22. What is granulomatous/ pyogranulomatous periadnexal dermatitis?
    the short-coat version of sebaceous adenitis; inflammatory disease directed against the entire periadnexal region with occasional destruction of the sebaceous gland
  23. What 2 breeds most commonly get granulomatous to granulomatous periadnexal dermatitis?
    vizsla, dachshund
  24. What are the clinical features of pyo/granulomatous periadnexal dermatitis? (4)
    annular areas of scaling and alopecia that enlarge and coalesce, intermittent edematous swelling of muzzle, lips, and eyes
  25. How do you treat pyogranulomatous to granulomatous periadnexal dermatitis? (4) [first choice]
    topical degreaser then spray with emolliant (applied for 30 min) weekly then decreased to PRN; spray with emolliant every day; omega-3 and omega-6 fatty acids
  26. How do you treat pyogranulomatous to granulomatous periadnexal dermatitis? (2) [second choice]
    cyclosporine (atopica), vitamin A supplement [systemic- use this method when topical only first choice treatments are not feasible for the owner (a lot of work)]
  27. What is the etiology of ichthyosis?
    hereditary and usually congenital
  28. What breeds are usually associated with ichthyosis? (5)
    norfolk terrier, jack russell, golden retriever, american bulldog, cavalier king charles spaniel
  29. How do you get a definitive diagnosis of ichthyosis?
  30. Describe the ichthyosis that Norfolk terriers get. (4)
    epidermolytic ichthyosis- suprabasal keratinocyte vacuolation and lysis, hypergranulosis, marked hyperkeratosis
  31. Describe the ichthyosis that jack russell terriers, golden retrievers, and american bulldogs get.
    Non-epidermolytic ichthyosis- laminated orthokeratotoic hyperkeratosis on biopsy
  32. Describe clinical presentation of ichthyosis in jack russells. (4)
    non-epidermolytic ichthyosis, severe, thick adherent scale, severe yeast infections
  33. Describe clinical presentation of ichthyosis in golden retrievers. (3)
    autosomal recessive non-epidermolytic ichthyosis, large soft white adherent scaling, ventral hyperpigmentation
  34. Describe the clinical presentation of ichthyosis in american bulldogs. (6)
    autosomal recessive non-epidermolytic ichthyosis, dissheveled coat after birth, brown adherent scale, large white scale, yeast overgrowth, +/- pruritus
  35. What types of ichthyosis have genetic tests?
    golden retrievers, american bulldogs- autosomal recessive non-epidermolytic ichthyoses (2 different gene mutations)
  36. Describe the clinical presentation of ichthyosis in CKCS. (8)
    congenital non-epidermolytic ichthyosis and keratoconjunctivitis sicca and ichthyosiform dermatosis, present at birth, curly hair, autosomal recessive, abnormal nail growth, orthokeratotic hyperkeratosis
  37. How do you treat ichthyosis in CKCS. (2)
    • no successful treatment for skin- moisturizing, emollient sprays, vitamin A
    • ocular treatment to prevent progression of keratitis
  38. What primary keratinization disorders occur in the cat? (4)
    [all very rare] feline acne, feline seborrhea, sebaceous adenitis, ichthyosis
  39. Describe feline acne pathologic process.
    idiopathic disorder of follicular keratinization (unlike canine acne, occurs in young AND adults)
  40. What are the clinical features of feline acne? (10)
    crusts, comedones, chin/lips, may progress to papules, pustules, folliculitis, furunculosis, cellulitis, alopecia, edematous/thick
  41. How do you diagnose feline acne? (3)
    • classic lesions (comedones)- rule out demodex, dermatophytosis, yeast/pyoderma
    • culture for secondary bacterial infections
    • chin edema- rule out eosinophilic granuloma with biopsy
  42. What do you see on biopsy of feline acne? (6)
    follicular keratosis, plugging, dilatation, [if advanced] perifolliculitis, folliculitis, furunculosis
  43. How do you treat feline acne?
    • clip fur, antiseborrheic/follicular flushing shampoo, [if papules/secondary infection] topical mupurocin 3 weeks, +/- oral antibiotics for deep infections/inflammation
    • once controlled, find minimum maintenance therapy
Card Set
Derm3- Keratinization
vetmed derm3