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Flashcards in Pathology Deck (35):
1

What is the visual presentation of hyperkeratosis

A scaly skin rash
Build up of keratin layer

2

What are the 4 main reaction patterns of inflammatory skin diseases

Spongiotic-intraepidermal oedema e.g. eczema
Psoriasiform- elongation of the rete ridges e.g. psoriasis
Lichenoid-basal layer damage e.g. lichen planus and lupus
Vesiculobullous- blistering e.g. pemphigoid, pemphigus

3

What is the characteristic of lichenoid disorders

Damage to basal epidermis
Most common condition is lichen planus

4

How does lichen planus present

Itchy flat topped pink/purple papules
Affects wrists, forearms, shins and ankles
May get lacy, white streaks in cheeks - Wickham's striae

5

what is the main feature of immunobullous diseases

Blisters
(vesicles and bullae)

6

What is pemphigus

Rare autoimmune bullous disease
Autoantibodies cause damage to the junctions between skin cells
Loss of junction integrity causes severe blisters
4 subtypes

7

How can you treat pemphigus

Responds to steroids

8

What is the most common subtype of pemphigus

Pemphigus vulgaris
80% of cases

9

Describe the cause of pemphigus vulgaris

Autoantibodies made against desmoglein 3
This usually maintains desmosomal attachments
Immune complexes form and complement is activated
Proteases are released and dissolve the attachments between cells - leads to acantholysis

10

what is acantholysis

breakdown of intercellular adhesion sites
common to all types of pemphigus

11

What causes bullous pemphigoid

Antibodies attack the hemidesmosomes that attach the basal cells to the basement membrane
Complement is activated and the surrounding tissues are damaged

12

How does bullous pemphigoid present

Subepidermal blisters
Tense blisters
when they burst, they leave erosisons - deep
Unlikely to affect mucosa
typically localised to one area or widespread on trunk/ limbs

13

What would show up if you did immunofluorescence on a bullous pemphigoid sample

Linear pattern of IgG antibodies would show up along the basement membrane

14

What condition is dermatitis herpetiformis associated with

Coeliac disease

15

How does dermatitis herpetiformis present

Extremely itchy lesions
Symmetrical
Often affects the elbows, knees, buttocks
The hallmark is papillary dermal microabscesses

16

Which HLA group is dermatitis herpetiformis associated with

HLA-DQ2 haplotype

17

What would a dermatitis herpetiformis sample look like under immunofluorescence

IgA deposits seen at the tips of the dermal papillae

18

What is the aetiology of acne

Increased androgens during puberty cause increased activity of sebaceous glands
Keratin and sebum plugs the pilosebaceous unit
Glands get blocked, inflamed then rupture
Infection with other bacteria causes inflammation etc

19

what is the normal distribution of acne

face, upper back, anterior chest
High concentration of sebaceous glands

20

What is the clinical presentation of rosacea

Recurrent facial flushing
Erythema
Visible blood vessels
Pustules and papules
Thickening of skin Rhinophyma - enlarged red nose

21

How can you differentiate between acne and rosacea

Rosacea does not have comedones - black/white heads

22

What are some triggers of rosacea

Sunlight
Alcohol
Spicy foods
Stress

23

What are some treatments for acne

Avoid oily substances and triggers
Topical treatments = bezoyl peroxide, topical retinoid, antibiotics
Systemic - antibiotics, oral retinoid (isoretinoin)

24

How do retinoids work

topical ones dry skin up by shrivelling the sebaceous glands and reducing secretion
Oral ones have many side effects

25

Describe the presentation of acne vulgaris

Comedones - black/white heads
Pustules and papules
cysts
erythema

26

What is a potential complication of acne

scarring

27

How can acne be graded

mild - scattered papules, small pustules and comedones
moderate - numerous papules, pustules and scarring
severe - cysts, nodules and significant scarring

28

Where on the body does rosacea normally appear

Nose, chin, cheeks and forehead

29

How can you treat rosacea

Reduce exposure to triggers - diet & wear suncream
Topical = metronidazole, ivermectin
Oral tetracycline - long term
Vascular laser for telengectasia
Rhinophyma - surgery

30

how do you treat lichen planus

symptomatically
usually burns out after 12-18 months
Can use topical steroids
Oral if very severe

31

what is Nikolsky’s sign

when the top layer of skin skips away from the lower ones when rubbed slightly
Positive in pemphigus

32

which areas of the body are typically affected by pemphigus vulgaris

scalp, face, axillae, groins
Mucosal involvement (eyes, genitals) is very common

33

Which condition has higher risk, pemphigus or pemphigoid?

Pemphigus
Very high mortality if untreated

34

How do you treat pemphigoid

Systemic steroids
Other immunosuppressive agents
Tetracycline
Topicals: emollients, topical steroids, topical antisepsis / hygiene measures

35

How do you treat pemphigus

Systemic steroids
Other immunosuppressive agents
Topicals: emollients, topical steroids, topical antisepsis / hygiene measures