Test 3: skin Flashcards
(145 cards)
1
Q
— prevents water loss and protect from environmental insults
A
enclosing barrier
stratum corneum
2
Q
3 ways skin acts as barrier
A
continuously shed- desquamation
hydrophobic
inherent immune system= keratinocytes, langerhands, dendritic cells and lymphocytes
3
Q
A
4
Q
basal layer of skin attaches to basement membrane by —
A
hemidesmosomes
5
Q
what do merkel cells do
A
sensory in skin, can tell if hair is moved
6
Q
histiocytosis is cancer of —
A
langerhans cell- can spontaneously regress
7
Q
melanocytes transfers melanin to —
A
keratinocytes
8
Q
what causes hyperpigmentation after injury such as constant scratching
A
melanocyte
9
Q
vitiligo is also called
A
depigmentation
leukoderma
loss of melanocytes
10
Q
is this malignant?
A
no not melanoma
flat/macules of pigment
lentigo simplex
incidental finding
11
Q
A
melanocytoma
raised black nodule on haired skin
melanoma- usually in oral cavity
12
Q
merkel cells are mechanoreceptors in — and hair follicles
A
tylotrich pads
13
Q
keratinization is also called
A
cornification
keratinocytes deposit keratin to form barrier
14
Q
sarcoma has —intermediate filament
A
vimentin
15
Q
carcinoma has — intermediate filament
A
keratin
16
Q
— have hemidesmosomes that attach to basement membrane
A
stratum basale
17
Q
stratum basale is the — layer with slow cycling stem cells
A
progenitor layer
18
Q
stratum spinosum attaches by —
A
desmosomes
19
Q
where can you find langerhans cells
A
stratum spinosum
20
Q
what does filaggrin do?
A
takes keratin filaments and packs them together
contains keratohyalin granules
found in the stratum granulosum layer
21
Q
— is the outermost layer of skin that is fully keratinized, anucleate and dead
A
stratum corneum
continuously shed
mortar and bricks
22
Q
primary abnormalities of cornification are —
A
mutations in the enzymes, structural proteins or lipids that form the outer layer of skin
23
Q
fish scale disease is called
A
ichthyosis
genetic condition of scaling due to faulty formation of stratum corneum
24
Q
xerosis means
A
dry skin
25
how does cornification work
1) Cleavage of keratinocyte cytoplasmic contents
2) Compaction of keratinocytes
* Binding of keratin via Filaggrin
* Replacing cell membrane via Transglutaminase
3) Lipid bilayer formation
26
stratum corneum with retained nuclei
parakeratosis
27
how is lipid bilayer formed in skin
lamellar granules will unfurl and dump lipid into junction between granular and corneum layer
lipids hold corneocytes together and repels water- provides moisture and hydrophobic barrier
28
harlequin ichthyosis
defective lamellar bodies- no lipids in top layer
can't slough stratum corneum
29
what happens with golden retriever ichthyosis
shedding/scaling
abnormal lipid
30
Epidermolytic ichthyosis Keratin mutation
Norfolk terrier
become very pigmented and scaly
31
cell membrane in corneum layer becomes--- by ---
cornified envelope
transglutaminases (TGM1)
32
jack russel
transglutaminases (TGM1) mutation
cells membrane is not changed into cornified envelope
33
what causes desquamation
sloughing/shedding of skin
enzymes
34
Epidermolysis bullosa
problem with basement membrane- skin falls off, hoof falls off
epidermis is not anchored to dermis
35
clear zone in the basement membrane seen on electron microscopy
lamina lucida
36
part of basement membrane that contains primarily type IV collagen
lamina densa
37
part of basement membrane that anchors fibrils and type VII collagen
sublamina densa
38
39
blisters
Epidermolysis Bullosa Acquista
problem with basement membrane- leads to blister and epidermis not attaching to dermis
40
what causes wrinkles in shar pei
excess hyaluronic acid- filler
can lead to vesicles
41
ehlers-danlos
problem with collagen
affects connective tissue, primarily the skin, joints, and blood vessel walls.
42
43
sebaceous gland in hair follicle is what type of secretion
holocrine
44
hair cycle
anagen- growing
telogen- arrested
45
furunculosis
rupture of hair follicle
leads to hair loss
can be secondary to inflammation in infundibulum of hair follicle →folliculitis
46
what hormones inhibit hair growth
Glucocorticoids
Estrogen
47
what hormones stimulate hair growth
thyroid hormone and androgens
48
Tylotrich hairs are ---
mechanoreceptors that attach to merkel cells
49
sebaceous adenitis
problem with sebaceous gland, leads to decrease in lipids, corneum can't slough, leads to scaling
50
eccrine sweat galnds (atrichial) are found ---
paw pads
empty directly onto surface of skin
51
apocrine sweat glands (epitrichial) are found ---
empty into hair follicle
52
papules- little raised lesions
demodex infestation
53
plaques- large flat lesion
eosinophilic granuloma complex
54
pustule → papule filled with pus
eosinophilic or neutrophilic
55
pustule and crust
56
crust vs scale
crust- ruptured pustule, cell debris, bacteria
scale- dandruff, stratum corneum
57
hemorrhagic crust
58
scale
59
hypothyroidism will do what to blood work?
hypercholesterol
mild anemia
60
eschar resulting from thermal burn
61
bullae
62
vesicles- smaller then bullae
63
wheal- hives- solid firm raised
64
macules- flat/even with skin surface
sertoli cell tumor producing estrogen
65
patches- flat/ even with skin surface
66
patches- flat/ even with skin surface
>1 cm
67
erosion
above basement membrane
68
ulcer
below basement membrane
69
comedomes - blackheads
70
comedo can be caused by
demodex mites
or
filled with keratin
71
where are scabies and demodex found?
demodex- in hair follicle
scabies- on skin surface
72
hyperplastic change resulting from chronic friction or inflammation
Lichenification
73
epidermal collarette
rums of flaking scale and the erosion of the center
74
itching is also called
pruritus
75
caused by
epidermal collarette
superficial pyoderma- caused by Staph Pseudintermedius
76
what is the most common cause of pyoderma in dogs
staph pseudintermedius
77
name 4 chronic changes
Alopecia
lichenification
erythema
hyperpigmentation
78
with chronic skin trauma what will happen to the hair follicles, glands and dermis
hyperplasia and folliculitis
sebaceous glands- hyperplasia
apocrine gland- cystic dilation and inflammation
dermis- fibrosis
79
sub-epidermal vesicular pattern/ pustular dematitis
80
Perivascular Dermatitis
81
lichenoid Interface Dermatitis
82
Epidermal Vesicular and Pustular Dermatit
83
Nodular and Diffuse Dermatitis- panniculitis
84
Folliculitis/ perifolliculitis and furunculosis
85
Atrophic Dermatoses
86
Acantholysis is the hallmark of --- which is driven by a Type II hypersensitivity reaction to intercellular adhesion molecules.
pemphigus foliaceus
antibodies attack adhesion molecule between keratinocytes
87
two differentials
superficial pyoderma
or
Pemphigus foliaceus- autoimmune type II reaction
88
three differentials for filliculitis
staph pseud
demodex
dermatophytosis (ring worm)
89
what can cause this
steroid- cause epidermal atrophy and hair loss/atrophy
90
Perivascular Dermatitis
Inflammatory cells
aggregate around
blood vessels
nonspecific
91
dermal edema/ space between epidermal cells
spongiosis
92
chronic perivascular will cause
Epidermal hyperplasia
Acanthosis
Spongiosis
Rete ridges
93
Orthokeratotic vs Parakeratotic hyperkeratosis
ortho- normal formation, just alot of keratin
para- abnormal, still has nucleus
94
type 1 hypersensitivity reaction
mast cell histamine
produce wheal/ hive
95
superficial perivascular dematitis can be caused by hypersensitivity disorders such as --- or by ---
flea bite hypersensitivity
atopy- the genetic tendency to develop allergic diseases such as allergic rhinitis, asthma and atopic dermatitis (eczema)
food allergy
ectoparasitism- sarcoptic mange
96
Pruritus vs Pruritic
* Pruritus = unpleasant sensation which provokes the desire to scratch
(itching)
*Pruritic = itchy
97
what three things can cause this
* Superficial trauma
*Bacterial
* Fungal- Malassezia
98
Lichenification: thickening of the skin associated with accentuation of the normal skin markings
hyperpigmentation
99
what does Malassezia look like
snow man or foot prints - fungus
100
flea bite hypersensitivity reaction
101
sarcoptic mange- ears, elbows, eyes
Notoedres cati - "feline scabies"
102
what causes parakeratosis
increased epidermal turnover or metabolic disease
can be caused by trauma, malassezia (fungi) infection
corneum with nucleus
103
Zinc Responsive Dermatosis with Pa rakeratosis
zinc is needed for epidermal differentiation
Arctic breeds but any breed possible if poor diet, scaly plaques on face and pressure points. Perivascular dermatitis with epidermal and follicular parakeratotic hyperkeratosis
104
Zinc-responsive dermatosis occurs in --- and causes the formation of ----
Arctic breeds but any breed possible if poor diet, scaly plaques on face and pressure points. Perivascular dermatitis with epidermal and follicular parakeratotic hyperkeratosis
105
Superficial necrolytic dermatitis (SND)
(Hepatocutaneous syndrome)
causes parakeratosis
skin disorder in dogs caused either liver disease (hepatocutaneous syndrome) or less likely glucagonoma (glucagonoma syndrome). Characteristic low magnification features: parakeratotic hyperkeratosis (red), acanthosis with intracellular edema in spinous layer (pallor- white), hyperplasia of basal layer keratinocytes (blue); so-called “red, white, and blue” appearance. Poor prognosis
106
Superficial necrolytic dermatitis (SND) is caused by --- and forms --- in the skin
liver disease (hepatocutaneous syndrome) or less likely glucagonoma (glucagonoma syndrome),
faulty proteins- have very low animo acids
effects paw pads, lips and genitalia
Characteristic low magnification features: parakeratotic hyperkeratosis (red), acanthosis with intracellular edema in spinous layer (pallor- white), hyperplasia of basal layer keratinocytes (blue); so-called “red, white, and blue” appearance. Poor prognosis
107
Superficial necrolytic dermatitis (SND)
108
Pathologic events target basal keratinocytes and dermoepidermal
junction
Interface Dermatitis
109
three causes of Interface Dermatitis
Immune complex deposition
Type II hypersensitivity reaction
Autoreactive cytotoxic T cells
110
what are some differentials for interface dermatitis
drug reaction
lupus
111
german short hair pointer
Exfoliative Cutaneous lupus
form of interface dermatitis
112
Erythema multiforme can be caused by ---. what happens to skin?
adverse drug reaction
Lymphocyte-mediated destruction of keratinocytes
113
--- is Lymphocyte-mediated destruction of keratinocytes
Erythema multiforme
114
how does interface dermatitis differ from pericascular dermatitis
usually immune dysfunction
attacks basal keratinocytes and dermoepidermal junction
can be caused by immune complex, type II hypersensitivity, autoreactive cytotoxic T cells, drug reaction
example: lupus or erythema multiforme
115
vesicle vs bulla
blisters
vesicle smaller then bulla
116
--- are keratinocytes which separate
completely from their neighbors, become round, with a round nucleus and eosinophilic cytoplasm
acantholytic cells
117
--- is the loss of cohesion between epidermal cells or keratinocytes. Results in the formation of clefts, vesicles and pustules.
Acantholysis (loosening of the spines Gk .)
not the same as acanthosis- hyperplasia of the stratum spinosum
118
Acantholysis- (loosening of the spines Gk .) is the loss of cohesion between epidermal cells or keratinocytes. Results in the formation of clefts, vesicles and pustules.
119
most common cause of acantholysis
Autoimmune disease due to autoantibody production to cell
adhesion molecules
type II hypersensitivity reaction
120
other then autoimmune what else can cause acantholysis
bacterial infection with release of proteolytic enzymes and bacterial
toxins
(rare) dermatophytosis (Trichophyton sp.)
severe edema (spongiosis)
121
caused by autoantibody to ---
desmocollin-1
Pemphigus Foliaceus
sterile pustules
Acantholysis, healthy neutrophils, no bacteria
122
Pemphigus vulgaris is caused by antibody to ---
desmoglein-3
(lower in the skin then Pemphigus foliaceus)
found in the mouth
Acantholysis with suprabasilar clefting
123
--- caused Acantholysis with suprabasilar clefting and is found in the mouth
Pemphigus vulgaris
Desmoglein-3 autoantibody
get tombstone effect
124
--- causes tombstone effect basal cells stay cause disease does not attack hemidesmosomes
Pemphigus vulgaris
Acantholysis with suprabasilar clefting
mouth
Desmoglein-3 autoantibody
125
PF vs pyoderma
PF- no bacteria, healthy neutrophils
pyoderma- + bacteria, necrotic cells, smaller, minimal acantholysis
126
PF has autoantibody to --
intracellular molecule in the desomones that hold cells together
causes cells to break apart
PF= desmocollin-1 autoantibody
PV= Desmoglein-3 autoantibody (mouth)
127
blistering disorder of the basement membrane caused by autoantibody formation
epidermolysis bullosa aquisita
bullous pemphigoid
128
can peel off skin
Co ngenital Epidermolysis Bullosa
129
skin peeling off
Epidermolysis Bullosa
130
nodular/diffuse dermatitis will have infiltrate with ---
(1) neutrophilic (e.g. bacterial)
(2) eosinophilic (e.g. parasitic or eosinophilic granuloma)
(3) histiocytic - chronic granulomatous or pyogranulomatous lesions (e.g. mycobacteria, fungal, foreign body)
131
acid fast stain showing mycobacteria what type of dermatitis?
infectious nodular/diffuse
132
what are two causes of noninfectious diffuse/nodular dermatitis?
Eosinophilic collagenolytic granuloma
Often associated with hypersensitivity disorder
133
what type of organism cause nodular/diffuse dermatitis?
mycobacteria, fungal
134
How does the character of the infiltrate of nodular/diffuse dermatitis give clues to cause?
epithelioid macrophages= granuloma =mycobacteria or fungus or foreign body
neutrophilic (e.g. bacterial)
(2) eosinophilic (e.g. parasitic or eosinophilic granuloma)
135
--- forms scabs with oily exudate, in dogs often idiopathic and sterile
panniculitis
136
inflammation of the hair follicle
folliculitis
137
follicle rupture with inflammation;
Furunculosis
138
What are the three major causes of folliculitis?
bacteria infection- staph pseud
dermatophyte- ringworm
demodex mites
139
what kind of bacteria causes folliculitis?
Staph. pseud
140
ringworm is also called
dermatophytosis (fungi)
141
Dermatophytosis is a Specific group of fungal organisms that utilize --- in hair
keratin
ringworm= Microsporum, trichophyton, epidermophyton
cause folliculitis and furunculosis
142
clinical presentation of folliculitis
alopecia
nodules
143
What inflammatory reaction occurs when the hair follicle ruptures?
granulomatous
144
atrophic dermatoses cause atrophy of skin and is caused by ---
steroids
or
spontaneous Hyperadrenocorticism
145
caused by steroid use
calcinosis cutis
spontaneous Hyperadrenocorticism
or from steroid use
