dermatology - high yield Flashcards
1
Q
what is the water proof barrier of skin
A
keratin layer
2
Q
what does the keratin layer contain
A
corneocytes
3
Q
what does the granular layer consist of
A
large keratinocyte granules
4
Q
what do the large keratinocyte granules conatain
A
fillagrin and involucrin
5
Q
what does the prickle cell layer contain
A
desmosomes that anchor cells together
6
Q
what is the epidermal layer closest to the dermis
A
basal
7
Q
how thick is the basal layer
A
one cell thick
8
Q
what is the metabolically active layer of the epidermis
A
the basal layer
9
Q
what are the 4 epidermal cells
A
keratinocytes, langerhans cells, merkel cells and melanocytes
10
Q
what makes up 95% of the cells in the epidermis
A
keratinocytes
11
Q
where do keratinocytes originate
A
in the basal layer
12
Q
where do keratinocytes end up
A
in the stratum coneum
13
Q
what do keratinocytes do
A
produce cytokines and are involved in immune response
14
Q
where are melanocytes found
A
in the basal layer
15
Q
what do melanocytes do
A
produce melanin that forms a protective overcap over the nucleus of cells
16
Q
what is eumelanin
A
brown/black
17
Q
what is phaemelanin
A
red/yellow
18
Q
where are langerhans cells found
A
in the prickle cell layer and dermis
19
Q
where are langerhans cells formed
A
in bone marrow
20
Q
what are langerhans cells
A
dendrictic cells involved in the immune system
21
Q
how to langerhans cells work
A
attach to antigen and present it in the lymph nodes
22
Q
where are merkel cells found
A
in the basal layer
23
Q
what are merkel cells
A
mechanoceptors sensitive to light touch
24
Q
anagen
A
growth phase
25
how long does anagen last
3-7 years
26
catagen
involuting stage
27
how long does catagen last
28 days
28
what is telogen
resting phase
29
when does telogen occur
everyday
30
3 layers of the dermis
lamina lucida, lamina densa, sub lamina densa zone
31
what does the dermis contain
fibroblasts, macrophages, langerhans cells, mast cells
32
what senses vibration
meissners corpuscles
33
what senses pressure
pacinian corpuscles
34
what senses painful stimuli
free nerve endings
35
where are aebaceous glands found
everywhere - especially face, chest and upper back
36
what gland is affected in acne
sebaceous gland
37
what are apocrine glands part of
pilo sebaceous unit
38
what do sabaceous glands release
oil
39
what do apocrine glands produce
oily fluid, odorous
40
why is the oily fluid smelly in apocrine glands
due to decompisition by bacteria
41
where are apocrine glands found
armpits, groin, eyelids, ears
42
what is the function of eccrine glands
cool down the body
43
where are eccrine glands found
everywhere especially hands, feet armpits and forehead
44
what is the role of keratinocytes
to release chemokine and cytokine and sense pathogens via surface receptors and produce anti microbial peptides that kill pathogens
45
what are the main antigen presenting cell in skin
langerhan cells
46
what do langerhan cells contain
birbeck granule
47
what to langerhans cells do
present pathogens to T cells
48
what T cells are found in the epidermis
CD4 and CD8
49
what T cells are found in the dermis
CD4 T cells
50
what T cells are involved in inflammation
CD4 and T helper cells
51
what T cell is psoriasis associated with but dermatitis isnt
TH1
52
what t cell is atopic dermatitis associated with but psoriasis isnt
TH2
53
what t cell is associated with both psoriasis and atopic dermatitis
TH17
54
examples of conditions with inappropriate inflammatory responses
psoriasis, urticaria, skin tumours, atopic dermatitis, bullous pemphigoid and SLE
55
what are prophyrias
manifestations in the skin due to accumulations of porphyrins
56
what does reduced activity of the enzymes that produce heam lead to
increase porphyrins
57
what is prophyria cutanea tarda due to
reduced activity of uroprophrinogen decarboxylase
58
symptoms of prophyria cutanea tarda
blisters, milia, hyperpigmentation, hypertrichosis, solar urticaria
59
how to diagnose prophyria cutanea tarda
plasma screen and urine test (woods lap)
60
what is erythropoietic protophyria caused by
reduced activity of ferrochelectase
61
signs of erythropoueric protophyria
burning senstation, no physical signs, pain in sunlight, swelling and itching
62
investigations of prophyrias
plasma screen, RBC porphyrins, transaminases
63
what causes acute intermittent porphyria
reduced activity of PBG deaminase
64
what is the lamina propia
a layer of loose connective tissue found in mucous membranes like the respiratory tract
65
what builds up in acute intermiitent porphyrias
porphobillogen
66
what builds up in erythropoietic protoporphyria
protoporphyrin
67
what type of hypersensitivity is bullous pemphigoid
type 2
68
what causes bullous pemphigoid
auto antibody deposition on the basement membrane
69
what are the auto antibodies in bullous pemphigoid developed against
hemi desmosomes
70
clinical features of bullous pemphigoid
deep tense blisters which are itchy and located around the flexures
71
is the nikolsky sign in bullous pemphigoid positive
no
72
who does bullous pemphigoid tend to affect
the elderly population
73
how to diagnose bullous pemphigoid
skin biopsy and immunofluorescence
74
what does immunoflourenscece in bullous pemphigoid show
deposition of IgG and C3 at the dermo epidermal junction
75
what is the management of bullous pemphigoud
potent topical corticosteroids or oral corticosteroids, immunosuppressants and antibiotics
76
what is pemphigus vulgaris
an autoimmune condition where there is deposition of IgG autoantibodies in the epidermis
77
clinical features of pemphigous vulgaris
flaccid, superficial blisters that are painful but nt itchy
78
is the nikolksy sign positive in pemphigus vulgaris
yes
79
what is the most common presenting symptom of pemphigous vulgaris
oral mucosa being affected
80
what has a higher mortality pemphigus vulgaris or bullous pemphigoid
pemphigoid vulgaris
81
how to diagnose pemphigoid vulgaris
skin biopsy and immunofluorescence
82
what does immunofluorescnce of pemphigus vulgaris show
deposition of IgG auto antibodies in the epidermis causing a chicken wire appearance
83
what is the management of pemphigus vulgaris
oral corticosteroids
84
what is dermatitis herpetiformis
an autoimmune condition caused by deposition of IgA autoantibdies in the dermis
85
what is dermatitis herpetiformis strongly correlated with
coeliac disease
86
clinical features of dermatitis herpetiformis
itchy, vesicular lesion on the extensor surfaces
87
diagnosis of dermatitis herpetiformis
skin biopsy and immunofluorescence
88
what does immuno fluresnce in dermatitis herpetiformis look like
deposition of IgA in granular pattern in the upper dermis
89
what is the management dermatitis herpetiformis
gluten free diet - dapsone can help
90
what are the antibodies against in pemphigous vulagris
desmoglein
91
what is epidermolysis known as
butterfly skin
92
inheritance of epidermolysis
autosomal dominant usually
93
history of epidermolysis
young child with fragile skin blisters all over body rubbing skin causes painful tear
94
presentation of actinic keratosis
scaly rash over temples and nose which has lesions red and pink in colour
95
risk factors for actinic kertosis
outdoor occupation, pale skin, not applying suncream
96
presentation of psoriasis
symmetrical sharply demarcated scaley erythematous plaques involving extensor surfaces, scalp, sacrum, hands, feet trunk and nails
97
peak onset of psoriasis
15-25 or 50-60
98
cause of psoriasis
multifactorial
99
histology of psoriasis
epidermal acanthosis, parakeratosis, elongated rete ridges on histology
100
presentation of guttate psoriasis
acute and spotty
101
presentation of palmoplantar pustular
painful to walk on
102
what does psoriasis demonstrate
koebner phenomenon and auspitz sign
103
systemic disease associated wuth psoriasis
psoriasitic arthritis, metabolic syndrome, crohns, cancer, uveitis, depression, alcohol, smoking
104
managemnet of psoriasis
vit d analogue, coal tar, dithranol, steroids, keratinolytics, photo therapy, immunosuppression and immune modulation
105
examples of vit D analogues
calcitriol calcipotriol
106
pathophysiology of eczema/dermatitis
spongiosis and inflammatory cell infiltertrate
107
presentation of eczema/dermatitis
ill defined erythematois itchy rash
108
pathogenesis of contact allergic dermatitis
type 4
109
histology of contact allergic dermatitis
spongiotic dermatitis
110
pathogenesis of contact irritant dermatitis
trauma (soap, water)
111
histology of contact irritant dermatitis
spongiotic dermatitis
112
pathogenesis of atopic dermatitis
genetic and environmental factors resulting in inflammation
113
histology of atopic dermatitis
spongiotic
114
pathogenesis of drug related dermatitis
type 1 or 4
115
histology of drug related dermatitis
spongiotic and eosinophils
116
pathogenesis of photo inficed dermatitis
reaction to UV light
117
histology of photo induced dermatitis
spongiotic
118
pathogenesis of lichen simplex
physical trauma to skin - scratching
119
histology of lichen simplex
songiotic dermatitis and external trauma
120
pathogenesis of stasis dermatitis
physical trauma to skin - hydrostatic pressur e
121
histology of stasis dermatitis
spongiotic dermatitis and extravasation of RBCs
122
what is Th2, IL4, 5 and 6 and filaggrin gene mutation assocated with
atopic dermatitis
123
diagnosis of atopic dermatitis requires
itch plus 3 or more of the followng - visible flexural rash, history of delxural rash, history of atopy, generally dry skin, onset before the age of 2
124
management of atopic dermatitis
irritant avoidance, soap substitution, emollient, topical steroids, photo therapy, systemic immunosuppressants, biologics
125
what is acne vulgaris
inflammatory disease of pilosebaceous unit
126
process of acne development
increased production of sebum, poral occlusion, cutibacterium acne colonisation, dermal inflammation
127
features of acne
comedones, pustules, papules, cysts, nodules, erythema, sebborhoea
128
secondary features of acne
scarring - atrophic, icepick, hypertrophic/keloid, hyperpigmentation
129
what does acne mostly affect
face, upper back, anterior chest
130
management of acne
avoid oily substances, benzoyl peroxed, vit A derivative, antibiotics
131
systemic management of acne
antibiotic - tetracycline, isotretinoin
132
who does rosacea typically affect
women aged 30-60
133
features of rosacea
papules, pustuesm erythemia of nose chin, cheeks, forehead, facial flushing
134
what can rosacea cause
rhinophyma, telangiectasia, conjuctivitis
135
management of rosacea
avoidance of aggravating factors, topical antimicrobials, oral tetratcycline
136
example of topical antimicrobial
metronidazole, ivermectin
137
how can rhinophyma be treated
with isotrenoin, vascular laser and surgery
138
who does lichen planus affect
middle aged
139
pathophysiology of lichen planus
T cell mediated inflammation targeting unknown protein in skin and mucosal keratinocytes
140
lichen planus features
violaceous flat topped shiny papules affecting volar wrists, forearms, shins, ankles, wickhams striae
141
what is wickhams striase
longitudinal nail ridges, hyperpigmentation, hypertrophy
142
management of of lichen planus
emollients symptomatic topical oral steroids, photo therapy
143
how long does lichen planus last
12-18 months
144
first line management of psoriasis
emollient, potent corticosteorid, vit D analogue
145
histology of psoriasis vulgaris
acanthosis
