Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

YEAR 5: Histopathology - PK Edited > Histo: Skin Pathology > Flashcards

Histo: Skin Pathology Flashcards

1
Q

How thick is a normal epidermis, dermis and subcutaneous fat put together?

A

6 mm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What types of fibres are found in the layer underneath the epidermis?

A

Collagen

Elastic fibres

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What structures are found within the dermis?

A
  • Blood vessels
  • Sweat glands
  • Hair follicles
  • Sebaceous glands
  • Nerve fibres
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How is palmar-plantar skin different from skin in other parts of the body?

A

There are no sebaceous glands

There is a very thick corneal layer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Describe the effects of ageing on the skin.

A

Skin becomes fragile with very little epidermis

Collagen and elastic fibres are of poor quality

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

List some different types of inflammatory reaction patterns in the skin.

A
  • Vesiculobullous - forms bullae
  • Spongiotic - becomes oedematous
  • Psoriasiform - becomes thickened
  • Lichenoid - forms a sheeny plaque
  • Vasculitic - associated with vasculitis
  • Granulomatous - associated with granulomas
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is bullous pemphigoid? Describe the macroscopic appearance.

A
  • Vesiculobullous condition
  • Occurs in elderly patients on their flexor surfaces
  • Characterised by the formation of tense bullae (that do not easily break)

NOTE: it has a 10-20% mortality

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Outline the pathophysiology of bullous pemphigoid.

A
  • Autoimmune disorder driven by IgG and C3 which attack the basement membrane by binding to hemidesmosomes
  • They recruit eosinophils which release elastase which further damages anchoring proteins (anchoring lower keratinocytes to the basement membrane)

Subepidermal bulla

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How can bullous pemphigoid be definitively diagnosed?

A

Immunofluorescence will show IgG and C3 along the dermo-epidermal junction

Linear deposition of IgG along the basement membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Describe the macroscopic appearance of pemphigus vulgaris.

A

Blisters are flaccid meaning that they rupture easily exposing a red raw surface underneath

Nikolsky’s sign positive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Outline the pathophysiology of pemphigus vulgaris.

A

IgG-mediated disease where the damage is occuring within the keratinocyte layers in the stratum spinosum (layer above the basement), thus is intraepidermal bulla

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is acantholysis?

A
  • Loss of intercellular connections leading to loss of cohesion between keratinocytes

NOTE: this can occur due to a lot of dermatological conditions so immunofluorescence is needed to identify where the immune-mediated attack is taking place

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Describe the macroscopic appearance of pemphigus foliaceus.

A
  • You rarely see intact bullae because they are so thin and fragile
  • You are likely to see some flaky remnants of old bullae

Elderly people too

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Outline the pathophysiology of pemphigus foliaceus.

A

IgG-mediated attack on the outer layer of keratinocytes (where the stratum corneum is found) - come let’s get some beers

Corneum
Lucidem
Granulosam
Spinosum
Basal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Describe the appearance of discoid eczema.

A
  • Very itchy and found on the flexural surfaces
  • Presents with discoid plaques
  • particularly in a round shape
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Describe the clinical presentation of contact dermatitis.

A
  • Itchy erythematous rash usually on the hands or feet (areas most commonly exposed to irritants)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is hyperparakeratosis?

A
  • Thickening of the skin on the surface where the patient has been scratching
  • Also seen in psoriasis
  • The epidermis gets thicker
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What type of inflammatory skin reaction is eczema?

A

Spongiotic because there is oedema between the keratinocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What are the main immune mediators in eczema?

A
  • T cell mediated
  • Eosinophils are also recruited

NOTE: this pattern is also seen in drug reactions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Describe the typical presentation of plaque psoriasis.

A
  • This is a psoriasiform reaction pattern
  • Tends to present as silvery plaques on the extensor surfaces
21
Q

How is the keratinocyte turnover time different in psoriasis compared to normal skin?

A
  • Normal skin turnover = 50 days (time for keratinocyte to go from the bottom of the epidermis to the top)
  • Psoriasis = 7 days
  • This leads to thickening of the epidermis and you get a layer of parakeratosis at the top
22
Q

Which layer of the epidermis disappears in plaque psoriasis and why?

A

Statum granulosum - there is not enough time to form it

23
Q

What can neutrophil recruitment to the epidermis in plaque psoriasis cause?

A

Formation of Munro’s microabscesses

24
Q

What is lichen planus and what are its main features?

A
  • Lichenoid reaction pattern
  • T-cell mediated
  • Presents with papuls and plaques that are slightly purplish in colour on the wrists and arms
  • In the mouth it presents as white lines (Wickham striae)
25
Q

Describe the histological appearance of lichen planus.

A

Sawtoothing of rete ridges and civette bodies (dead cells that release their nucleus)

26
Q

What type of inflammatory skin reaction results in pyoderma gangrenosum? And what other conditions are associated with this rash?

A

Vasculitic

Crohn’s
UC

27
Q

Describe the classic macroscopic appearance of seborrhoeic keratosis.

A

‘Stuck on’ appearance

28
Q

Describe the appearance of sebaceous/epidermal cyst.

A
  • Smooth surface
  • Non-mobile
  • Tend to have a punctum
  • Can get infected/rupture
  • Can smell really bad
29
Q

Describe the histological appearance of a sebaceous cyst.

A
  • Looks like the surface has become invaginated to form a cyst
  • Lined by squamous epithelium
30
Q

Describe the macroscopic appearance of a basal cell carcinoma.

A

Rolled, pearly edge with a central ulcer and telangiectasia

31
Q

Describe the histological appearnace of a basal cell carcinoma.

A
  • Cancer arises from the keratinocytes along the bottom of the epiderms (basal cells)
  • They can infiltrate through the basement membrane
  • They are locally infiltrative but don’t metastasise
32
Q

What is Bowen’s disease?

A

Squamous cell carcinoma in situ

33
Q

Describe the normal migration of melanocytes as they mature.

A

As they mature they become smaller and go deeper

34
Q

What are some clinical signs suggestive of a malignant melanoma?

A
  • Assymetry
  • Border irregularity
  • Colours
  • Diameter
  • Evolution
35
Q

Describe the histological appearance of malignant melanoma.

A
  • Melanocytes start migrating upwards through the epidermis (pagetoid spread)
  • They become active and lose the ability to differentiate
  • Melanoma thickness > 4 mm has a > 50% mortality
36
Q

What is auspitz’ sign

A

Pintpoint bleeding after rubbing on psoriatic plaque

37
Q

What type of hypersensitivity reaction is:
atopic dermatitis
contact dermatitis
psoriasis

A

atopic dermatitis - type I (IgE)
contact dermatitis - type IV (t cell, delayed)
psoriasis - type IV (t cell, delayed)

38
Q

What rash is associated with coeliac

A

Dermatitis herpetiformis

39
Q

What sign is positive in TENS / SJS? And what other condition is it positive in?

A

Nikolsky sign (rubbing the epidermis off)

Also positive in pemphigus vulgaris (as bullous made in the epidermis)

40
Q

Describe the rash of erythema multiforme

A

Annular target lesions

41
Q

Most common skin cancer?

A

BAsal cell carcinoma

42
Q

Rank the malignant skin cancers in likelihood of metastasising

A

Melanoma > SCC > BCC

43
Q

Name of salmon pink rash, christmas tree distribution that appears after HHV6 and HHV7 infection?

A

Pityriasis Rosea

44
Q

Most important prognostic factor for melanoma

A

Breslow thickness

45
Q

What is a buckshot appearance indicative of on skin biopsy

A

Melanoma

46
Q

Most common type of malignant melanoma?

A

Superficial spreading

47
Q

Second most common type of melanoma?

A

Nodular

48
Q

Slow growing melanoma in sun exposed areas of elderly caucasians?

A

Lentigo maligna

YEAR 5: Histopathology - PK Edited (29 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions