SAD - Chapter 12 - Congenital Keratinization Defects Flashcards
An autosomal dominant mutation in what gene(s) of Rhodesian or Thai ridgebacks result(s) in formation of a dermoid sinus?
fibroblast growth factors (FGF3, FGF4, FGF19)
T/F: Animals with follicular parakeratosis have normal nasal planums and footpads.
TRUE
What are the clinical features of urticaria pigmentosa?
macular and/or crusted papular rash on head and neck, +/- pruritus, +/- hyperpigmentation
What is the pigmentary abnormality with color dilution alopecia?
irregularities in melanin transfer and storage – mature (stage IV) melanosomes are stored irregularly in hairs and epidermal keratinocytes and vacuolization of melanocytes in some hair bulbs
Darier disease is due to mutations in genes that encode what molecules?
calcium pumps
What are the clinical features of dermatomyositis?
skin lesions in areas of mechanical trauma (face, periocular, muzzle, tips of ears, carpal/tarsal region, digits, tip of the tail, onychorrhexis): alopecia, erythema, scale, crust, ulceration
Cats with a blue or cream-colored coat carry what dilution gene?
Maltese dilution gene
An autosomal recessive ectodermal dysplasia-skin fragility syndrome of Chesapeak Bay retrievers has been shown to be due to what defects?
reduced number of partially formed desmosomes; due to lack of plakophilin-1 and anomalies in desmoplakin and keratins 10 & 14
___ is longitudinal splitting of the distal end of a hair.
trichoptilosis
___ is a rare disorder of young intact male Kerry blue terriers where affected dogs have multiple, hard, brittle follicular spicules.
Spiculosis
In addition to hair loss, animals with ectodermal dysplasia have abnormalities in what other organ systems?
dentition and glandular formation/function (epitrichial and atrichial sweat, sebaceous, lacrimal, tracheal and bronchial)
An autosomal recessive primary seborrhea has been reported in what breed ofr cats?
Persians
Dystrophic epidermolysis bullosa results from decreased expression of what protein? Due to a defect in what gene?
collagen VII; mutation in COL7A1 gene
What can worsen the skin lesions of dermatomyositis?
trauma and solar exposure
What is the skin extensibility index for dogs affected with Ehlers Danlos? Cats?
> 14.5% - dogs, >19% - cats
What are clinical signs of myositis in animals with dermatomyositis?
dysphagia, megaesophagus, high-stepping stiff gait, asymptomatic muscle atrophy
In the German Shorthaired Pointer, ______ is an autosomal recessive trait associated with decreased expression of laminin-332.
junctional epidermolysis bullosa
Familial footpad hyperkeratosis has been described in what breed(s)?
Irish terriers and Dogue de Bordeaux
____ is a neural tube defect resulting from incomplete separation of the skin and neural tube during embryonic development.
Dermoid sinus
T/F: The presence of melanin clumping is diagnostic for color dilution alopecia.
False - indicates action of dilution genes, does not necessarily mean the animal has color dilution alopecia
In the German Shorthaired Pointer, junctional epidermolysis bullosa is an autosomal recessive trait associated with decreased expression of what?
laminin-332 laminin 5)
What are the clinical lesions of canine Darier disease?
alopecia, erythema, scaling –> plaquelike
What is the primary cause of acral mutilation syndrome?
pathologic lesions at the level of the primary sensory neuron, decrease in promeninence of the spinal ganglia and dorsal roots
With epidermolysis bullosa simplex, where does clefting occur?
basal layer of epidermis (most superficial of epidermolysis bullosa types)
Darier disease due to abnormal calcium homeostasis has been reported in what breed(s)?
English setters, Doberman pinscher