CP 63 - inflammatory skin diseases

Question 1

what the 2 types of chlamydia

Answer 1

a] Trachoma is a tropical disease which infects the corneum and conjuctiva. Common cause of blindness.

b] Mild disease due to Chlamidia types d-k, aquired during birth from infection in genital tract

Question 2

what can cause retina infections

Answer 2

toxoplasma - cat poo

toxocara canis - dog poo

Question 3

what is macular degeneration

Answer 3

Damage to macule, the central part of vision.

• dry - age related
• wet - new vessel growth beneath retina

Question 4

what can cause cataracts

Answer 4

senil degeneration 
rubella 
down's syndrome 
irradiation
Diabetes 
Uveitis

Question 5

what conditions can happen in the retina?

Answer 5

ischaemia
hypertensive retinopathy
diabetic retinopathy

Question 6

what tumours can arise from the retina?

Answer 6

retinoblastoma - genetic, occurs in retina,

Melanoma - arise from melanocytes of Uveal tract (Iris, ciliary body or choroid)

Question 7

what is leprosy?

Answer 7

chronic granulomatous infection which can involves nerves, loss of sensation

Question 8

what causes leprosy?

Answer 8

mycobacterium leprae

Question 9

what are some of the common fungal infections

Answer 9

ringworm - tinia pedis (athelete’s foot), tinea cruris (groins) - infectiob by trichophuton species

trush - candida infection

Question 10

what is another name for eczema?

Answer 10

dermatitis

Question 11

what are the 3 clinical stages of dermatitis

Answer 11

1 - acute dermatitis (skin red, weeping serous exudate +/- small vesicles.)

2- subacute dermatitis (skin is red, less exudate, itching ++, crusting.)

3 - chronic dermatitis (skin thick and leathery secondary to scratching)

Question 12

what are the microscopy of the different stages of dermatitis

Answer 12

1 - spongiosis (intercellular oedema within epidermis)

2 - Chronic inflammation - predominantly superficial dermis.

3 - Epidermal hyperplasia and hyperkeratosis - mild in acute dermatitis, marked in chronic dermatitis

Question 13

what can atopic eczema be associate with?

Answer 13

asthma and hay fever

Question 14

what kind of reaction id eczema?

Answer 14

type 1 hypersensitivity to allegen

Question 15

what is contact irritant dermatitis

Answer 15

direct injury to skin by irritant, eg acid, alkali, strong detergent, etc

Question 16

what is contact allergic dermatitis

Answer 16

• nickel, dyes, rubber. Act as haptens which combine with epidermal protein to become immunogenic.

Question 17

what is seborrhoeic dermatitis ?

Answer 17

affect areas rich in sebaceous glands: scalp, forehead, upper chest

Question 18

what is nummular dermatitis

Answer 18

coin shaped lesions

Question 19

what is psoriasis?

Answer 19

well defined, red oval plaques on extensor surfaces - knee elbows, sacrum

fine silvery scale, Auspitz sign

Question 20

what is the distinct psoriasiform hyperplasia

Answer 20

regular elongated club shaped rete ridges

thinning of epidermis over dermal papillae

parakeratotic scale

collections of neutrophils in scale

Question 21

what is the pathogenesis of psoriasis

Answer 21

massive cell turnover

Question 22

what is the aetiology of psoriasis

Answer 22

problems in the MHC on chromosome 6p2 (same area involved in other autoimmune disorder)

required environmental trigger factors

Question 23

what does patients with psoriasis have increased risk of?

Answer 23

non-melanoma skin cancer

Question 24

what types of different lupus erythmatosus are there?

Answer 24

discoid - skin only

systemic - visceral disease +/- skins

Question 25

how is lupus erythematosus present clinically?

Answer 25

Red scaly patches on sun-exposed skin +/- scarring, scalp involvement causes alopecia

Question 26

what would butterfly rash on cheek and nose indicate?

Answer 26

SLE

Question 27

what sort of condition is lupus erythematosus

Answer 27

Auto-immune disorder primarily affecting connective tissues of the body

Question 28

what are the microscopical feature of lupus erythematosus

Answer 28

thin atrophic epidermis, . Inflammation and destruction of adnexal structures. LE band - IgG deposit in basement membrane

Question 29

what are presentation of dermatomyositis

Answer 29

peri-ocular odema and erythema (heliotropic rash)

Question 30

what does dermatomyositis indicate in some population?

Answer 30

In adults 25% associated with underlying visceral cancer

Question 31

what does the bullous disease

Answer 31

Formation of fluid filled blisters

Question 32

what does intra-epidermal bulla represent?

Answer 32

pemphigus

Question 33

what does sub-epidermal bulla represent?

Answer 33

pemphigoid

Question 34

what is pemphigus

Answer 34

Group of disorders characterised by loss of cohesion between keratinocytes resulting in an intraepidermal blister.

Question 35

how does pemphigus manifest?

Answer 35

Autoantibodies, directed against intercellular material

Question 36

how does bullous pemphigoid manifest?

Answer 36

Autoantibodies to glycoprotein in basement membrane.

Question 37

what is deematitis herpetiformis

Answer 37

Small intensely itchy blisters. Extensor surfaces

Question 38

what can dermatitis herpetiformis indicate?

Answer 38

coeliac disease

Question 39

what is acanthosis nigricans

Answer 39

darty warty lesions in armpits

Question 40

what can acanthosis nigricans indicate

Answer 40

internal malignancy

Question 41

what can xanthoma indicate

Answer 41

hyperlipaemis

Question 42

what can porphyria indicate

Answer 42

problem with production of haem

Question 43

what can porphyria be presented?

Answer 43

acute abdo pain, psycho problem, peripheral neuropathy, urine goes dark on light exposure

Question 44

what is the most common form of porphyria?

Answer 44

porphyria cutanea tarda

Question 45

what can cause porphyria cutanea tarda

Answer 45

20% FH, 80% acquired through Hep C

Question 46

what is the most common malignant skin tumour?

Answer 46

basel cell carcinoma

Question 47

aetiology for BCC?

Answer 47

sun exposed site (face), occasionally radiotherapy

Question 48

what are some of the clinical presentation for BCC?

Answer 48

early - nodule, late - ulcer | microscopically - tumour composed of islands of basaloid cells with peripheral palisade

Question 49

what can cause squamous cell carcinoma?

Answer 49

``` UV irradiation (sun exposed) radiotherapy - treatment of melonoma chemical exposure - tars, mineral oils chronic scars/ulcers immunosuppression - renal transplant patients at increased risk drugs (new drugs for melanoma) ```

Question 50

what are some of the clinical presentation of SCC?

Answer 50

Nodule with ulcerated, crusted surface

Question 51

is SCC particularly invasive

Answer 51

no really (still more invasive for BCC) -

Question 52

what is actinic keratosis

Answer 52

dry scaly patches of skin caused by damage from years of sun exposure - patches can be pink brown in colour pre-malignant disease of SCC

Question 53

what is the cause of actinic keratosis

Answer 53

dysplasia to squamous epithelium

Question 54

what is the function of melanocytes

Answer 54

to form melanin which is transferred to epidermal cells to protect the nucleus from UV radiation

Question 55

what are the benign tumour arise from melanocytes?

Answer 55

naevi (moles)

Question 56

what are the malignant tumour arise from melanocytes?

Answer 56

melanoma

Question 57

what is naevi?

Answer 57

local benign collections of melanocytes

Question 58

what is naevus syndrome

Answer 58

families with increased incidence of melanoma, multiple clinically atypical moles, increased risk of developing melanoma

Question 59

what is the acronym for identifying naevus and melanoma

Answer 59

melanoma - asymmetrical borders uneven colour variation diameter >6mm

Question 60

what is the causes of melanoma

Answer 60

sun exposure (especially short intermittent severe exposure) race - celtic with red hair FH - dysplastic naevus syndrome

Question 61

what is lentigo maligna

Answer 61

elderly ppl have face patches which is slow growing, flat, pigmented patches

Question 62

what is the microscopic feature of lentigo maligna

Answer 62

Proliferation of atypical melanocytes along basal layer of epidermis. Skin also shows signs of chronic sun damage.

Question 63

will lentigo maligna become invasive?

Answer 63

might do later on in the disease, melanocytes may invade dermis with potential to metastasis

Question 64

where does acral lentigenous melanoma affect the most?

Answer 64

palms and soles, occasionally subungula

Question 65

which race is acral lentigenous melanoma affect the greatest?

Answer 65

afro-caribbeans

Question 66

what is the superficial spreading melanoma

Answer 66

commonest type in Britain

Question 67

where does superficial spreading melanoma

Answer 67

Early: flat macule. Late: blue/black nodule

Question 68

what is nodular melanoma

Answer 68

Starts as pigmented nodule. +/- ulceration. Poor prognosis.

Question 69

what is the microscopic features of nodular melanoms

Answer 69

invasive atypical melanocytes invade dermis to produce nodules of tumour cells

Question 70

what is breslow thickness

Answer 70

measure on microscope from granular layer of epidermis to base of tumour

Question 71

what is the treatment of melanoma

Answer 71

surgery | BRAF inhibitors 60% melanoma have mutation in b-raf gene