Dermatopathology Flashcards
1
Q
Summaries the Dermal reaction patterns
A
- Dermal fibrosis: increased collagenous connective tissue
-
Fibrosis
- desmoplasia/scirrhous response when induced by neoplasia (carcinomas, typically)
- Fibroplasia: normal healing response
-
Dermal atrophy: thinning of the dermal layer
- hyperadrenocorticism, topical steroids, chronic ischemia, advanced age, starvation
- Dermal edema: perivascular or interstitial, can contribute to epidermal edema
-
Dermal deposits: can presents as papules, nodules or plaques
- Amyloid - plasmacytomas in dogs, hyperglobinemia, idiopathic
- Calcium:
- Calcinosis circumscripta: tumor-like growth composed of discrete calcium deposits surrounded by granulomatous inflammation; surgical removal curative
- Calcinosis cutis: dermal calcium deposits associated the Cushings
- Lipid:
- Xanthomas - lipid deposits in the dermis that induce granulomatous inflammation; abnormal circulating lipids
2
Q
What is Ichthyosis?
A
- Heterogenous group of inherited, usually congenital alteration in epidermal cornification (stratum corneum) multiple species affected
- severe orthokeratotic hyperkeratosis
- Can be fatal (harlequin calf)
3
Q
What is Hereditary Zinc Deficiency?
A
- Abnormalities in zinc absorption and metabolism
- Parakeratotic hyperkeratosis
- Associated w/ thymic hypoplasia and diarrhea
- Autosomal recessive
- Lethal acrodermatitis of bull terriers: non-responsive to oral Zn supplementation
- Cattle- respond to oral Zn supplementation
4
Q
What is Epidermolysis bullosa
A
- Heterogenous group of diseases
- Cutaneous blister formation in response to minor mechanical trauma
- Poor dermal/epidermal cohesion
- Reported in horses, cattle, sheep, dogs, cats,
- Genetic mutation in structural proteins
5
Q
What is Aplasia cutis congenital (epitheliogenesis imperfecta)
A
- Distinct disease of swine
- Defect typically in caudal half of body
- Some piglets have hydroureter and hydronephrosis
6
Q
What is Congenital hypotrichosis?
A
- Partial or complete hair loss
- May be assocciated with other congenital abnormalities (brachygnathism, dental defects, thymic or genital abnormalities)
- Predisposes animals to sunburn, adverse reaction to extreme temperatures, bacterial/fungal infections
7
Q
What are the 2 types of Hypotrichosis associated with pigmentary alteration?
A
- Black hair follicular dysplasia
- bi- or tri- colored black & white dogs
- hair loss confined to pigmented areas
- onset: weeks to months old
- Rare hereditary disease
- Color-dilution alopecia
- Slow progressive development
- Onset 4 m to 3 y
- Most common in blue doberman
- relatively uncommon
8
Q
What is canine dermatomyositis?
A
- idiopathic inflammatory condition of skin, muscle, and occasionally blood vessels
- skin lesions usually develop in juvenile dogs at 7 weeks to 6 months
- Variability severity ad presentation with waxing/waning clinical signs
- Early skin lesions: pustules, vesicles, papules, nodules
- Skin lesions evolve into erythematous, crusty, ulcerated areas of alopecia w/ pigmentation abnormalities
- Histologic changes are variables subtle, and or non-specific
9
Q
What are the 2 categories of hereditary hypopigmentation?
A
- Melanocytopenic hypomelanosis (absences of melanocytes)
- Melanopenic hypomelanosis (melanocytes present but defective
- Chediak-Higashi syndrome, cyclic hematopoiesis
10
Q
What is primary seborrhea
A
- Suspected inherited skin disease
- increased epithelial turnover without release of keratin
- Excessive scaling, crust, greasy coat
- Predisposed to skin infections (bacterial/fungi)
- Rule out other causes of seborrhea (acquired)
11
Q
What is acanthosis nigricans?
A
- Primary or idiopathic form occurs predominately in young dachshunds
- Bilaterally symmetric, axillary hyperpigmentation (subtle at first)
- Progresses to lichenification and alopecia
12
Q
What is collagen dysplasia
A
- group of inherited diseases; abnormal dermal collagen
- Enzyme defects of collagen synthesis
- Synonyms: Ehlers Danlos syndrome, cutaneous asthenia, dermatosparaxis
- Many species affected (including humans)
- Very loss, fragile skin
13
Q
What is Hereditary Equine Regional Dermal Asthenia (HERDA)?
A
- hyperelastosis cutis
- recessive inheritance
- very loose elastic skin
- non-healing wounds
- scarring