Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

PathY5 > Skin pathology > Flashcards

Skin pathology Flashcards

(83 cards)

Start Studying
1
Q

What condition is this?

A

Bullous Pemphigoid

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

What is the most common cancer in the Western World?

A

Basal Cell Carcinoma

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

Does BCC metastasise?

A

Does not metastasise, but can cause large disfigurement as it occurs in areas exposed to the Sun

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

Which is the largest organ in the human body?

A

Skin

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

What are the functions of the skin?

A

Protection:
Þ Essential barrier between external environment and internal body
Þ Protects against mechanical, chemical, osmotic, thermal and
UV damage and microbial invasion

Metabolic
Þ Role in vitamin D synthesis
Þ Body temperature regulation

Sensation
Þ Sensory organ for touch, temperature, pain and other
stimuli

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

What are the 3 layers of the skin?

A

Epidermis
Dermis
Hypodermis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the epidermis?

A

Outermost layer

Formed by layers of keratinocytes undergoing terminal maturation

This involved increased keratin production and migration towards external surface – known as cornification

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

What are the cells of the epidermis?

A

Keratinocytes

Melanocytes (melanin production and pigment formation)

Langerhans cells (antigenpresenting dendritic cells)

Merkel cells (sensory mechanoreceptors)

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

What are the layers of the epidermis?

A

Divided into layers deep to superficial:
stratum basale
stratum spinosum
stratum granulosum
stratum lucidum
stratum corneum

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

How long do keratinocytes travel?

A

Keratinocytes travel from stratum basale to corneum in 30-40 days

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

What is the dermis?

A

Tightly connected to epidermis via dermo-epidermal junction

Consists of two layers: superficial papillary layer and deeper reticular layer

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

What is contained in the dermis?

A

Contains fibroblasts (synthesise ECM), mast cells, blood vessels, cutaneous sensory nerves and skin appendages (e.g. hair follicles, nails, sebaceous and sweat glands)

Pilosebaceous unit: Sebaceous glands release their glandular secretions into the hair follicle shaft. The hair follicle is associated with an arrector pili muscle which contract to cause the follicle to stand upright.

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

What is the hypodermis?

A

Subcutaneous tissue: Major body store of adipose tissue

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

How thick is skin (3 layers)?

A

6mm

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

What is the main function of the epidermis?

A

The epithelial cells that line your skin and
mucous membranes allow body fluids to come
out (e.g. sweat and sebum)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Summarise the dermis

A

o Supporting structure
o Made up of collagen and elastic fibres
o Contains blood vessels, sweat glands, sebaceous
glands, hair follicles and nerve fibres

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Which part of the body has the most sebaceous glands?

A

Nose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Which part of the body has no hairs?

A

Palms and soles

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

How does skin change with age?

A

o Much thinner epidermis
o More fragile dermis – poorer quality collagen and
elastic bundles
§ Hence elderly bruise easier

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

Which part of the skin is involved in the inflammatory reaction pattern?

A

epidermis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What are the different types of inflammatory reaction pattern?

A

o Vesiculobullous: forms bullae
o Spongiotic: becomes oedematous
o Psoriasiform: becomes thickened
o Lichenoid: forms a sheeny plaque
o Vasculitic: associated with vasculitides
o Granulomatous: associated with granulomas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What are the vesiculobullous conditions?

A

Bullous pemphigoid
Pemphigus vulgaris
Pemphigus foliaceus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is bullous pemphigoid?

A

Blistering condition in which you get IgG antibodies produced against BPAg1/2 –
these are protein components of the basement membrane between epidermis and dermis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What type of reaction is bullous pemphigoid?

A

Type II antibody-dependent hypersensitivity reaction

Autoimmune disorder driven by IgG and C3 which attack the basement membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Does BP kill?
High morbidity rate, particularly in elderly 10-20% mortality so must be recognised
26
How does BP present?
Present with tense blisters called bullae, particularly in flexor regions § The blisters tend to be a bit more robust than in pemphigus vulgaris as they are due to a deeper inflammation in the skin
27
What is the histology of BP?
§ Characteristic pattern § Complement is activated and it starts to attack the way in which keratinocytes sit on basement membrane § Lots of eosinophils are recruited releasing elastase § Result: damage to anchoring proteins that anchor the lower keratinocytes onto the basement membrane
28
What are the other causes of tense bullae?
bullae e.g. drug reaction -\> hence an immunofluorescence stain looking for IgG and C3 can be done to help diagnosis -\> forms band under immunofluorescence along basement membrane zone This can be done directly on specimen or indirectly using serum
29
What is pemphigus vulgaris?
o Blistering condition in which IgG antibodies are produced against desmoglein 1 and 3 which are essential cement proteins in the epidermis (anti-epithelial cell cement protein antibody) o As a result, keratinocytes split away from each other (acantholysis) o Blisters are thin and weak and easily rupture
30
What's the histology of PV?
Damage occurring within the keratinocyte layers § There is acantholysis (loss of intercellular connections leading to loss of cohesion between keratinocytes)
31
How can immunofluorescence be used in PV?
Immunofluorescence can be done to see IgG around the affected individual keratinocytes
32
What is pemphigus foliaceus?
o Rare o Bullae are rarely seen intact as they are so thin that they often come off -\> leaves an excoriated looking area o IgG mediated o Affects stratum corneum (top layer) o Immunofluorescence can be used
33
Do you remember the house analogy?
o Think of it as a house with a solid foundation (basement membrane) o The house is made of bricks (keratinocytes) that are joined together by cement o The house has a roof (keratin layer on the surface) o In bullous pemphigoid, all the damage is occurring between the lowest layer of bricks and the concrete foundation o The house becomes lifted off the basement membrane and the space gets filled with fluid o Bullous pemphigoid: bottom floor o Pemphigus vulgaris: first floor o Pemphigus foliaceus: roof
34
What are the spongiotic diseases?
Discoid eczema Contact dermatitis
35
What are the characteristics of discoid eczema?
o Atopic o Producing white plaques in flexor regions o Very itchy o Can become very extensive and look erythematous throughout body
36
What are the characteristics of contact dermatitis?
Due to latex gloves but can also occur from nickel, watch straps etc
37
What is the histology of spongiotic diseases?
o Spongiosis means that there is oedema (fluid between the adjacent keratinocytes) o Scratching at top -\> showing hyperparakeratosis (thickening of the skin on the surface where you have been scratching) o T cell mediated, and eosinophils recruited here too
38
What is a differential for an eczematous reaction pattern?
Drug reaction
39
What are the characteristic features of plaque psoriasis?
Classic example of psoriasiform: classic silvery plaques This occurs on extensor surfaces e.g. knuckles, elbows, knees There are other variants of psoriasis but this is the classic presentation Munro’s micro-abscesses: classically seen, sit at top of epidermis, accumulations of neutrophils Dilated vessels also seen
40
What is the histology of plaque psoriasis?
Skin is constantly shredding – the normal time for a stem cell to form a matured keratinocyte is ~56 days In psoriasis, shredding occurs rapidly -\> 7 days rather than 56 Many normal layers of epidermis are lost e.g. granular cell layer (stratum granulosum) – as there is not enough time to form it Epidermis is thickened as it is proliferating so rapidly – layer of parakeratosis at the top
41
What are the characteristics of lichen planus?
o Typically present with itchy, redpurple plaques on extensor distal surfaces e.g. wrist, as well as classical white lines in their mouth (Wickam striae) o Note: dermatologists always look inside mouth to assess buccal mucosa o T-cell mediated
42
What is the histology of lichen planus?
1. Lots of T cells 2. Band like inflammation between dermis and epidermis (unclear margin) § Lots of T lymphocytes § Bottom layer of keratinocytes damaged (apoptosis) -\> leads to band-like inflammation in between epidermis and dermis; unable to see where dermis finishes and epidermis starts § Second image is lower power image of same thing – you can see a band-like lymphocytic infiltrate just under the epidermis § This can be seen in lichen planus and also in mycosis fungoides
43
Characterise pyoderma gangrenosum
* This is an example of a lesion that does NOT fit into one of the categories * This is a common manifestation of many different underlying systemic diseases e.g. sclerosing cholangitis, hepatitis, IBD, leukaemia * Sometimes patients present with skin lesion due to an underlying nondermatological condition -\> must do further investigations and take a complete history
44
What are the characteristics of sebhorrheic keratosis?
* Common benign lesion * Looks like a pigmented cauliflower-like lesion * Completely harmless
45
What is the histology of sebhorrheic keratosis?
o Proliferating epidermis in an orderly fashion o As it is orderly, it is likely benign (disorderly is a sign of dysplasia, malignancy) o Horn cysts seen: entrapped keratin surrounded by a proliferating epidermis
46
What are the characteristics of a sebaceous cysts?
* Central puncture, smooth, round, circumscribed, non-mobile * Can get infected, inflamed, and rupture * Epidermis has invaginated into dermis * Benign * Can be very smelly, especially if rupture
47
What are the characteristics of BCC?
• Typically occurs in sun-exposed areas in elderly • Rolled pearly edge, central area of ulceration, telangiectasia • Also called rodent ulcer -\> can look like this following extensive ulceration • Surgery involves reconstruction – can be challenging
48
What is the difference between Cancer and dysplasia?
§ Epithelial cancer (e.g. breast, skin, prostate) involves issue with the epithelial cells. In skin, keratinocytes (epidermis) sit on the basement membrane -\> as soon as any of these break through the basement membrane and enter underlying mucosa (in skin, dermis) then it is CANCER rather than just dysplasia, as it now has the potential to metastasise e.g. via nerve, blood vesse
49
Do BCC metastasize?
Basal cell carcinomas do not metastasise – they are locally invasive
50
What is Bowen's Disease?
• Squamous cell carcinoma in situ • Large keratin horn o This is not cancer – it is pre-cancerous • It is key to find the lesion before it becomes malignant
51
What is the histology of Bowen's disease?
Keratinocytes are still within the epidermis, but they are behaving differently -\> larger, pleiomorphic, hyperchromatic, odd mitotic figures (disorganised growth pattern)
52
Is Bowen's disease neoplasia?
No, it is dysplasia. Dysplasia is divided into 1, 2 and 3 depending on grade level. Grade 3 (high grade) have high likelihood of turning into cancer if left alone
53
What is the difference between poorly differentiated and well differentiated?
o Poorly differentiated means cells are beginning to look less like the tissue they originate from; second diagram; cannot tell what kind of cancer it is as none of the underlying phenotype present any longer; worse prognosis o Well differentiated = still looks like epidermis
54
What is the precursor for SCC?
Bowen's Disease
55
What causes greater risk of recurrence?
Tumours can wrap themselves around nerve (perineural invasion) – 3rd diagram o Recurrence is greater in these cases -\> monitored more strongly post-op
56
What causes naevi?
Melanocytes are normally scattered on the basal layer of the epidermis -\> produce naevi when they start to accumulate and proliferate
57
What is an intradermal naevus?
nest of melanocytes within the dermis
58
What is a compound naevus?
nest within the epidermis and dermis
59
What is a junctional naevus?
group of melanocytes creating nests in the epidermis, typically occur in younger population
60
Can normal melanocytes be in the dermis?
Normal melanocytes can be present in dermis (unlike keratinocytes) – this is NOT malignancy As melanocytes mature, they drop from epidermis to dermis
61
What are characteristics of MM?
o Irregular outline o Variable pigmentation o Bleeding o Itchy o Growing o These are all worrying signs
62
What does ABCDE stand for in MM?
o Asymmetry o Border irregularity o Colours o Diameter o Evolution
63
What causes MM?
o Melanocytes are abnormally moving up through the epidermis (upward migration/pagetoid spread) o Bigger melanocytes than normal
64
What is the histology of MM in dermis?
Normally melanocytes get smaller as they mature and move into dermis § Here, they are the same size at the top and bottom and are mitotically active (replicate) § Usually, should not see mitotic components in melanocytic lesion in dermis as it is a sign of it being a malignant melanoma EXCEPT in pregnancy § Once the cells go into the dermis, become mitotically active and lack the ability to mature, then you get a diagnosis of malignant melanoma
65
How do you stage MM?
Staging of MM is based on depth (millimetres) – Breslow thickness o A melanoma with a thickness of \>4mm has a very high mortality (\>50%)
66
Can you have skin mets?
Yes: o Small papule that looks fairly benign o This turned out to be metastatic renal cell carcinoma
67
Lichen planus are which type of inflammatory reaction pattern?
Lichenoid
68
Where in the epidermis does the bullae in pemphigus vulgaris form?
Between the keratinocytes (intraepidermal)
69
Where in the epidermis does the bullae in bullous pemphigoid form?
subepidermal
70
White silvery plaques on extensor surfaces are seen in which condition?
Psoriasis
71
Breslow thickness is used to stage which skin cancer?
Malignant melanoma
72
Which common skin cancer does NOT metastasise?
Basal cell carcinoma
73
What condition is this?
Pemphigus Vulgaris
74
What condition is this?
Pemphigus Foliacus
75
What condition is this and what type of inflammatory disorder is it part of?
Discoid Eczema Spongiotic Disease
76
What condition is this?
Contact Dermatitis
77
What condition is this?
Plaque psoriasis
78
What condition is this?
Lichen planus
79
What condition is this?
Pyoderma Gangrenosum
80
What condition is this?
Sebhorreic Keratosis
81
What condition is this?
Sebaceous cyst
82
Label A, B, C and D
A. MM B. BCC C. SCC D. Bowen's Disease
83
What are these?
1. Benign Junctional Naevus 2. Compound Naevus

PathY5 (98 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions