Derm 1 Flashcards
1
Q
Skin
A
- Largest organ of the body
- See derm cases everyday as a small animal practitioner
2
Q
Anagen: most common phase in which animals?
A
- 90%: Poodles and humans= growing
- Only 9% in huskies=double coated
o Can take a year for their hair to grow back
o b/c most is in telogen=resting phase
o *permanently damaged
3
Q
What is follicular growth simulated by?
A
- TH, GH and melatonin
o Some dogs need melatonin in winter (Ex. bulldogs) - *needs protein
o If undernourished=trouble growing hair and hair will be BRITTLE
4
Q
What is follicular growth suppressed by?
A
- Estrogen
- Glucocorticoids
5
Q
Adnexal glandular secretions: functions
A
- Sebaceous: sebum (oil)
- Apocrine: sweat to protect skin surface
- Eccrine: foot sweat
6
Q
Panniculus (subcutis): functions
A
- Padding and anchoring
- Facilitates movement
- Stores fat, etc.
7
Q
Sources of injury: 2 broad categories
A
- Endogenous
- Exogenous
**usually multifactorial: might not be able to get them all under control
*try to find a PATTERN (on the animal, seasonal)
8
Q
What are the 4 responses of the epidermis to injury?
A
- Alterations in epidermal growth or differentiation
- Alterations in fluid balance and cellular adhesion
- Inflammatory lesions
- Alteration in pigmentation
9
Q
Hyperkeratosis: epidermis
A
- Normal in some locations (paw pads, nasal planum)
- *stratum corneum=many layers!
o Times of disease=can start to flake off - Ex. skunk with canine distemper virus (could see in the lesion)
- **Orthokeratosis=MORE COMMON
- Parakeratosis=less common (cells do NOT loss their nuclei=still present!)
o Quick and necrotic process
10
Q
Acanthosis: epidermis
A
- Hyperplasia of all layers except the stratum corneum of the epidermis
- Usually goes hand in hand with hyperkeratosis
- Ex. if mild acanthosis = milk keratosis
o **also down in hair follicles=plug them up
11
Q
Mouses response to doxycycline: epidermis
A
- Normal to mild epidermal hyperplasia to severe hyperplasia
o Acanthosis and hyperkeratosis
12
Q
Apoptosis: epidermis
A
- Can happen in skin (certain diseases)
- NOT often
- Cell dying randomly and on their own
13
Q
Edema: epidermis
A
- More common
- Might see ‘spines’ = attaches between the cells
- *caused by Staph and Malassezia spp. =epidermitis
14
Q
What might you see in dogs with Cushing’s?
A
- Epidermal atrophy
- *thin skin
15
Q
What is epitheliogenesis imperfecta?
A
- Bare segments with no skin
o Lots of bacteria can get in=usually die of septicemia - *see sporadically in cattle, puppies and pigs
- *congenital abnormalities
- if small=will close as it grows=scar tissue and can survive
16
Q
Leukoderma: epidermis
A
- Pigmentation that disappears
o Used to be pigmented and it is gone (can see melanin underneath) - Not common
17
Q
Lentigo: epidermis
A
- The places they rub: anus, nose, lips, ears
- *darker areas=not melanoma
- *normal for orange cats=will increase as they get older
18
Q
What are the responses to injury in the dermis?
A
- Alterations in dermal growth or differentiation
a. Atrophy
b. Fibrosis
c. Solar elastosis - Inflammatory lesions and depositions
19
Q
Granulation tissue: horses
A
- Make lots of it
- Skin grows a giant mass
- Well vascularized
20
Q
What is the response to injury of the adnexa?
A
- Alterations in growth or differentiation
a. Atrophy
b. Hypertrophy - Inflammatory
21
Q
Follicular physiological atrophy
A
- Growth of hair is SEASONAL and it is controlled by enivironmental and genetic factors
22
Q
Follicular pathological atrophy
A
- Hormonal abnormality
- Inflammation
- *often mixed together
23
Q
Folliculitis
A
- Usually starts with blood vessels
- Just by the bulb or sebaceous glands
24
Q
Panniculitis: primary and secondary causes
A
- Primary
a. Vitamin E deficiency
b. Vaccination: will usually resolve and go away (maybe hair loss, but unusual)
c. Infection - Secondary
a. Bacterial folliculitis and furunculosis
25
Q
Furunculosis
A
- Dark outline=edema
- Likely necrosis and an abscess may form and create a drainage tract
- **fully invades the tissue and has ruptured=PAINFUL
26
Q
What is the progression of folliculitis/furunculosis?
A
- Perivascular
- Mural
- Luminal
- Rupture
- Drain
27
Q
Sebaceous adenitis
A
- Can’t find any sebaceous glands: only a little bit remains
o Inflammation knocks it out - Ex. certain breeds: standard poodles
- Alopecia and bumpy skin
o Cannot produce sebum because of inflammation of glands
28
Q
Collagen dysplasia
A
- Ex. cocker spaniels
- *overly stretchy skin
29
Q
Ichthyosis fetalis
A
- Puppies and calves
- On feet and muzzle (sometimes ears)
o Charolais cattle=entire body - *don’t see much anymore=have ‘removed’ the genes
