Diseases of the Skin and Eye Flashcards Preview

Clinical Pathology > Diseases of the Skin and Eye > Flashcards

Flashcards in Diseases of the Skin and Eye Deck (69):
1

Virus that can cause scarring of the cornea and conjunctiva

VZV

2

2 forms of chlamydia that damage the cornea and conjunctiva

Trachoma: tropical disease. Common cause of blindness.
Chlamydia types d-k- mild disease: acquired during birth from infection in genital tract.

3

6 causes of cateracts

Senile degeneration
Rubella
Down's syndrome
Irradiation
Uveitis-inflammation of uvea (middle eye)

4

2 retinal infections

Toxoplasma: cat is host. Congenital infection causes severe bilateral disease. Aquired causes focal inflmmatory disease.
Toxocara Canis: from infected dog faeces, larva may migrate to retina and die causing localised inflammation.

5

3 types of retinal vascular disease

Ischaemia
Hypertensive retinopathy- flame shaped haemorrhages and exudates
Diabetic Retinopathy-dot and blot haemorrhages and exudates

6

2 types of macular degeneration

Dry macular degeneration (90%) Age related, common >60yrs. Progressive visual impairment, no treatment.
Wet macular degeneration (10%) New vessel growth beneath retina. Treat with drugs and lazers. Drugs inhibit vessel growth, injected directly into the eye.

7

2 types of tumours of the eye

Retinoblastoma
Melanoma

8

Retinoblastoma

Rare, 10% familial. Loss of Rb gene. Tumour in the retinal, treat with enucleation.

9

Melanoma

Arise in the melanocytes of the uveal tract (iris, ciliary body or choroid)
Type 1: good prognosis
Type 2: poor. Treat with radiotherapy and surgery.

10

Another word for genital warts

Condylomas

11

Superficial bacterial infection

Impetigo

12

Deep bacterial infection

Cellulitis
NF

13

Fish tank granuloma

Caused by mycobacteium marium.

14

Leprosy

Mycobacterium leprae. Chronic granulomatous infection. can involve nerves.

15

3 stages of eczma

Acute dermatitis
Subacute dermatitis
Chronic

16

Acute dermatitis

Red skin, weeping, serous exudate with or without vesicles.

17

Subacute dermatitis

Red skin, less exudate, really itchy and crusty

18

Chronic dermatitis

Skin thick and leathery, secondary to scratching

19

Spngiosis

Intercellular oedema within epidermis that you find in eczma

20

Clinical characterisitics of dermatitis

Chronic inflammation-predominantly superficial dermis. Epidermal hyperplasia and hypekeratosis.

21

5 types of dermatitis

Atopic eczma
Contact irritant dermatitis
contact allergic dermatitis
Seborrhoeic dermatitis
Nummular dermatitis

22

Coin shaped lesions, a type of dermatitis

Nummular dermatitis

23

Removal of psoriasis scab causes small bleeding points

Auspitz sign

24

Microscopic appearace of psoriasis

Psoriasiform Hyperplasia
-regular elongated club shaped rete ridges
-thinning of epidermis over dermal papilla
-parakeratoti (contain nuclei) scale
-collections of nuclei (munro microabscesses)

25

Pathogenesis of psoriasis

Massive cell turnover and inflammation

26

Causes of psoriasis

Genetic. Associated with MS/IBD
Environmental triggers-infection, stress, trauma, drugs, smoking.

27

Assocations of psoriasis

Arthropathy
CVD
Cancer (Basal cell carcinoma)

28

Discoid LE

Lupus that only affects the skin

29

Systemic LE-

Visceral disease

30

Microscopic appearance of lupus

Thin, atrophic epidermis. Infalmmation and destruction of adnexal structures.
Immunofluorescence shows LE band due to IgG deposited in basement membrane. i.e. antigens are sandwiched between keratinocytes and basement membrane.

31

Dermatomyositis

Perocular oedema (puffy eyes)
Photo sensitive distribution-heliotropic rash.
Myositis-prox muscle weakness. Can check for creatinine kinase.

32

Assocations of dermatomyositis

Visceral cancer

33

Microscopy of dermatomyositis

Dermal mucin

34

Bullous dieases

Fluid filled blisters

35

Pemphigus

Superifical blisters. Immunofluorescence- intercellular

36

Pemphigoid

Deeper blisters- subepidermal. Immunofluorescence-basement membrane

37

Pathogenesis of pemphigus

Loss of cohesion between keratinocytes resulting in an intracepidermal blister. Affects mucous membranes-mouth, anus etc.

38

Pathogenesis of pemphigoid

Subepidermal.
Elderly-large tense bullae, do not rupture easily, Can be localised or extensive.

39

Dematitis herpteiformis

Young patients. Small, intensly itchy blisters. IgA deposition in dermal papillae in IMF. Neutrophil microabscesses in dermal papillae.

40

Acanthosis nigrans

Dar warty lesions in armpits, associated with internal malignancy.

41

Necrobiosis lipodica

Red and yellow plaques on legs. Associated with DM

42

Erythema nodosum

Red nodules on shins. Associated with infections elsewhere e.g. lung.

43

Connective tissue tumours in the skin

Dermatofibroma

44

Porphyria Cutanea Tarda (PCT)

20% inhertied, 80% acquired (hep C or alcohol)
Enzyme deficiency- uroporphyrinogen decarboxylase. Results in a build up of porphyrin in the skin-tissue damage when exposed to sunlight. Blisters and scarring. Porphyrins in urine-go dark on light exposure

45

Most common malignant tumour

Basal cell carcinoma

46

Are metastases common in BCC?

No, rare

47

Causes of BCC

Sun exposure-pale skin more susceptivle
Radiotherapy
Immunosuppression
Gorlin's syndrome

48

Early clinical manifestation of BCC

Nodule

49

Late clinical manifestation of BCC

Roden tulcer with rolled edge. Ill defined and infiltrative. Tumour composed of islands of basaloid cells with peripheral palor. Can be pigmented.

50

Squamous cell carcinoma risk factors

UV radiation- tropical counties.
Radiotherapy
Hydrocarbon exposure-tars, mineral iols, soot
Chronic scars/ulcers e.g. Marjolin's ulcer
Immunosuppression
Drugs e.g. for melanoma

51

Appearance of SCC

Nodule with ulcerated, crusted surface and trabeculae of squamous cells showing cytological atypia.
5% metastasise- typically in lip, ear and perineum
High risk if bigger than 2cm or thicker than 4mm

52

Pre malignant disease that predisposes you to SCC

Actinic keratosis

53

Actinic keratosis

(grandpa) Scaly lesion with erythematous base. Only rarely progresses to invasive disease
May spontaneously resolve

54

Benign melanocytic cancer

Naevi (moles0

55

Malignant melanocytic cancer

Melanoma

56

2 types of naevi

Superficial-congenital or aquired
Deep-blue naevi (mongolion spot)

57

Families with increased incidence of melanoma. Multiple clinically atypical moles

Dysplastic naevus syndrome

58

Melanoma

Much rare than BCC and SCC. Incidence is increasing. Very dangerous and can metastasize widely.

59

Diagnosis of melanoma

Asymetrical
Borders uneven
Colour variation
Diameter >6mm
ABCD

60

Causes of melanoma

Sun exposure-short intermittent sever exposure
Race-rarer in people with darker skin
Family history-dysplastic naevus syndrome
Giant congential naevi-10% turn malignant

61

Lentigo maligna

Slow growing, flat, pigmented patches that grow on the faces of elderly people. Chronic skin damage. May eventually invade dermis to become lentigo maligna melanoma, which have the potential to metastasis

62

Acral lentigenous melanoma

Palms and soles. Commonest form in afro caribbeans- no marked skin damage as opposed to lentigo maligna

63

Commonest type of melanoma in britain

Superficial spreading malignant melanoma

64

Clinical appearace of superficial spreading malignant melanoma

Fat macule
Late- blue/black nodule

65

Genetic predisposition in superficial spreading malignant melanoma

BRAF mution-possible targe for anticancer agents

66

Nodular melanoma

Starts as a pigmented nodule, sometimes with ulceration. Poor prognosis.

67

Prognostic factors for melanoma

Breslow thickness- measure the thickness from granular layer of epidermis to base of tumour. 5yr survival rates. If 4mm 45-60% 5yr survival

68

Site of melanoma that give rise to a poorer prognosis

BANS- back, arms, neck scalp

69

Treatment for melanoma

Surgery
BRAF inhibitors.