Pathology of Skin Flashcards Preview

Dermatology > Pathology of Skin > Flashcards

Flashcards in Pathology of Skin Deck (115):
1

What is the peidermis mainly made up of

Maturing squamous cells

2

Where are melanocytes found

At the dermo-epidermal junction and in the basal layer

3

What is the ratio of melanocytes to basal cells

1:10

4

What is the granular layer rich in

Keratohyalin granules

5

What is the corneal layer made up of

Differentiated keratinised cells

6

What happens to corneocytes

They are shed from the surface and cause house dust

7

How is pigment shown

Melanocytes transfer pigment to keratinocytes via dendritic processes

8

Where are the Langerhan cells located

In the upper and mid-epidermis

9

Why are Langerhans cells important

In initiating inflammation

10

What is the difference in melanocytes in a pale skinned person compared to a darker skinned person

They have the same number of melanocytes but darker skinned people make more melanin

11

The matrix of the dermis is made up of what

Type 1 and type 3 collagen

12

What colour is a) collagen when and b) elastin when stained

Collagen is pink and elastin is blue

13

What is the ground substance of the dermis made up of

Hyaluronic acid and chondriotin sulphate

14

Describe the appearance and location of the papillary dermis

Thin and lies just beneath the epidermis

15

Describe the appearance and location of the reticular dermis

Thicker than the papillary dermis and contains type 1 collagen

16

What does the reticular dermis contain

Appendage structures - sweat glands, pilosebaceous units

17

What is the epidermal Basment Membrane made of

laminin and collagen IV

18

What type of cells appear to have halos around them

Melanocytes

19

What is parakeratosis

Persistence of nuclei in the keratin layer - the skin turnover is too high

20

Define papillomatosis

irregular epithelial thickening

21

Give an example of papillomatosis

Acanthiosis nigricans

22

What are the 4 main reaction patterns of inflammatory skin diseases

Spongiotic-intraepidermal oedema (eczema)
Psoriasiform-elongation of the rete ridges (psoriasis)
Lichenoid-basal layer damage (pemphigoid, pemphigus and dermatitis herpetiformis)

23

What are Munro micro abscess

A collection of neutrophils and classsically psoriasis

24

Where are 3 common sites of acne

Face
Upper back
Anterior chest

25

What are open comedones

Blackhead since it is oxidised

26

What causes a yellow head

A build up of Sebum and keratine cloggasge

27

Describe the aetiology of acne

Increased androgens at puberty, increased angrogen sensitivity of sebaceious glands
keratin plugging of pilosebaceious units
infection with anaerobic bacterium corynebacterium acnes

28

Rosacea is more common in females than males. true or false

True

29

What are some common features of rosacea

Recurrent facial flushing
Visible blood vessels
Pustules
Thickening of skin - rhinophyma

30

What are some triggers of rosacea

Sunlight
Alcohol
Spicy foods
Stress

31

What are sometimes found in the hair follicles under the microscope in patients with rosacea

Demodex mite in the sebaceious glands

32

What 2 things occur as a secondary phenomenon in many skin disease

eczema
herpes virus infection
burns

33

what type of disease have blisters as the primary feature

Immunobullous diseases

34

What are 3 examples of immunobullous diseases

Pemphigus
Bullous pemphigoid
Dermatitis Herpetiformis

35

What histologically happens in pemphigus

Loss of integrity of epidermal cell adhesion

36

What is the general treatment for pemphigus

Steroids

37

Who is usually affected by pemphigus

Middle aged men or women

38

In simple terms, describe pemphigus

Rare autoimmune bullous disease which is a problem involving cell to cell adhesion

39

What is the end result in pemphigus vulgaris

Acantholysis

40

What forms on the cell surface of pemphigus vulgaris

Immune complexes

41

What is the role of desmoglein 3 in pemphigus vulgaris

It maintains desmosomal attachments

42

What does Pemphigus Vulgaris produce

Fluid filled blisters which rupture to form shallow erosions

43

What areas of the body are affected by Pemphigus Vulgaris

Scalp
Face
Axillae
groin
Trunk

44

What process is common to all variants of pemphigus ?

Acantholysis (lysis of intercellular adhesion sites)

45

What is bullous pemphigoid

Subepidermal blister

46

What do the IgG antibodies do in Bullous pemphigoid

They react with a major and/or minor antigen of the hemidesmosomes anchoring basal cells to the basement membrane.

47

if you think a patient has presented with bullous pemphigoid, what should be done about it

Punch biopsy or elliptical incisional

48

What type of disease is dermatitis herpetiformis

A relatively rare condition that is autoimmune bullous disease

49

What areas of the body are affected by dermatitis herpetiformis

Elbows, knees and buttocks

50

What does dermatitis herpatiformis have a strong association with

Ceoliac disease

51

What haplotype is dermatitis herpetiformis

HLA-DQ2

52

What is the presenting complaint of dermatitis herpetiformis

Intensely itchy lesions-symmetrical

53

What is the hallmark of dermatitis herpetiformis

Papillary dermal microabscesses

54

What do IgA antibodies target in dermatitis herpetiformis

Gliadin component of ggluten but cross react with connective tissue matrix proteins

55

Immune complexes form in dermal papillae and do what?

Activate complement and generate neutrophil chemotaxins

56

What components of the skin give rise to tumours

All of them

57

Where are melanocytes derived from

Neural crest

58

Early in embryogenesis what mirgrates from the neural crest to what 3 places

Melanoblasts to the:
skin
Uveal tract (of the eye)
Leptomeninges (coverings in the prain)

59

once the melanoblasts have migrated and settled in the skin, what do they form

melanocytes

60

How is pigment transfered

via dendritic processes of the melanocytes

61

What gene is the determinant of what your pigmentation is like?

MC1R (Melanocortin 1 receptor)

62

What does one defective copy of MC1R cause

Freckling

63

What does two defective copies of the MC1R gene cause

Red hair and freckles

64

What does MC1R do?

turn phaeomelanin into eumelanin

65

What is the medical term for freckles

Ephilides

66

What are epihilides

Patchy increase in melanin pigmentation

67

What are Actinic lentigines?

Age or liver spots related to UV exposure

68

Where are you likely to see Actinic lentigines

Face, forearms and dorsal hands

69

In Actinic lentigines, What is there an increase in

Melanin and basal melanocytes

70

Melanoocytic naevi may be 1 of two types. What are these

Congenital or acquired

71

Why is a patient with melanocytic naevi at increased risk of developing melanoma

Based on the fact that they have so many increased melanocytes

72

What allows the formation of simple naevi

During infancy the melanocytes: keratinocyte ratio breaks down at a number of cutaneous sites

73

There are 3 types of naevi. What are these and where are the melanocytes

Junctional: clusters of cells at the DEJ
Compound: Junctional clusters and groups of cells in the dermis
Intradermal: entirely dermal

74

What are the majority of naevi

Compound

75

Describe a typical dysplastic naevi

Generally >6mm
Variegated pigment
Border asymmetry

76

What is a sporadic dysplastic naevi

Not inherited
One to several atypical naevi
risk of MM slightly raised

77

What is a familial dyplastic naevi

strong FH of melanoma
Autosomal inheritance
Lifetime risk of melanoma up to 100%

78

What are the 2 subdivisions of rarer naevi

Halo naevi and blue naevi

79

Describe halo naevi

They have a peripheral halo of depigmentation and show inflammatory regression and are overrun by lymphocytes

80

Describe blue naevi

Entirely dermal and consist of pigment rich dendritic spindle cells - the cellular variant may have mitoses and mimic melanoma

81

Most Spitz naevus are malignant. True or False

False - most are entirely benign

82

What do Spitz naevi consist of?

Large spindle and or epitheliod cells

83

The incidence of melanoma peak at what age

Middle age

84

What are 6 red flag signs that make you suspect melanoma

Change in shape
New pigmented lesion that develops in adulthood
Irregular pigmentation
Ulceration
Bleeding
Development of satellite nodules

85

What are the 4 main types of malignant melanoma

Superficial spreading
Acral/ mucosal
Lentigo maligna
Nodular

86

What is the most common type of melanoma and where do they appear

Superficial spreading - commonest on the trunk and limbs

87

What type of melanoma are common in sun bed users

Lentigo maligna melanoma

88

What is Vertical Growth Phase

When the melanoma cells invade the dermis forming an expansile mass with mitoses

89

Why is VGP important

Only tumours in the VGP can spread and kill

90

What is different about nodular melanoma compared to the others

It has metastatic potential from the beginning and therefore is considered more aggressive

91

What does melanoma prognosis largely relate to

Breslow depth and ulceration
Breslow= deepest tumour from granular layer mm

92

What does the suffix a/b mean when staging melanomas

a = no ulceration
b = ulceration

93

Where are common sites of metastatic spread

Skin/ soft tissue
Heart
Lungs
GI tract
Liver
Brain

94

What is the treatment for melanoma

Primary excision to give clear margins
sentinal node biopsy - if positive, regional lymphadenopathy

95

What is used for the treatment for advanced melanoma

Chemo
Immunotherapy
Genetic therapies

96

What is BRAF

an oncogene which drives cell proliferation

97

What are 3 types of precancerous dysplasias

Bowen's disease
actinic keratosis
Viral lesions

98

What is seborrhoeic keratosis?

Benign proliferation of epidermal keratinocytes

99

Where are common places to find seborrhoeic keratosis

Face and the trunk

100

Describe the appearance of seborrhoeic keratosis

stuck on appearance - greasy hyperkeratotic surface

101

What are the 3 main subtypes for BCCs

Nodular
Superficial
Infiltrative

102

Where do basal cells arise from

Epidermis

103

Histologically, superficial basal cell carcinomas often have what appearance

Picket Fence appearance

104

Where does Bowen's disease present

On the legs

105

Where does Actinic keratosis present

On the head and neck

106

Where do viral lesions present

Anogenital skin

107

Histologically what do precursors of squamous cell carcinoma show

Dysplasia

108

Describe Bowen's disease

mostly affects females on their lower legs
Scaly pathc / plaque
Irregular border
No dermal invasion

109

Describe the appearance of Actinic keratosis

Lots of wrinkles and scales, discrete plaques with crusty scale

110

What virus are Viral precursors often associated with

HPV

111

What type of HPV is associated with dysplasia

Type 16

112

What is the behaviour of squamous carcinoma

Generally good prognosis
Locally invasive
Low but definite risk of metastasis

113

What is the appearance of an angiosarcoma

Bluish purple often like a bruise and may bleed

114

Merkel cell carcinoma almost never malignant . True or False

False they are very malignant

115

What are Merkel cells

Pressure receptor cells in the skin