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Flashcards in 63 Diseases of the skin + eye Deck (42)
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1
Q

Which inflammatory diseases affect the cornea and conjunctiva? (3)

A

Herpes zoster.
Chlamydia A-C: blindess. D-K: conjunctivitis.
Acanthamoeba.

2
Q

What increases cataract risk? (6)

A
Senile degeneration.
Rubella.
Downs syndrome.
Irradiation.
Diabetes mellitus.
Uveitis.
3
Q

Which infections affect the retina? (2) How?

A

Toxoplasma: congenital is bilateral, acquired is focal.

Toxocara gondis: dog faeces, local inflammation.

4
Q

Which vascular diseases affect the eye? (2)

Appearances?

A

Hypertensive retinopathy: flame shaped haemorrhage.

Diabetic retinopathy: dot + blot haemorrhage.

5
Q

Where do melanomas of the eye occur?

Prognosis?

A
Uveal tract (iris, ciliary body, choroid).
Type 1: good prognosis. Type 2: bad.
6
Q

Differentiate between Herpes Simplex 1 + 2.

A

1 primarily causes cold sores.

2 primarily causes genital herpes.

7
Q

Differentiate between a furuncle and a carbuncle:

A

Abscesses. Furuncle involves one follicle, carbuncle involves more than one.

8
Q

What are the three stages of dermatitis (eczema)?

A
  1. acute - red skin, serous exudate ± vesicles
  2. subacute - red, less exudate, itching, crusting
  3. chronic - skin thick + leathery from itching
9
Q

What is seen in microscopy from eczematous skin? (3)

A

Spongiosis: intracellular oedema in epidermis.
Chronic inflammation.
Epidermal hyperplasia + hyperkeratosis.

10
Q

What is the appearance of psoriatic plaques?
Sign?
Associated with?

A

Well defined red, oval plaques on extensor surfaces with silvery scale.
Auspitz sign: removal of scale causes small bleeding points.
± pitting nails, sero-negative arthritis.

11
Q

What is seen in microscopy of psoriatic skin? (4)

A

Psoriasiform hyperplasia:
Elongated club shaped rete ridges.
Thinning of epidermis over dermal papillae.
Parakeratotic scale.
Collections of neutrophils (Munro micro abscesses).

12
Q

What is the aetiology of psoriasis?

A

PSORS in MHC on 6p2 implicated.

Infection, stress, trauma, drugs.

13
Q

What co-morbidities are associated with psoriasis? (4)

A

Arthropathy.
Cardiovascular disease.
Non melanoma skin cancers (BCC).
Lymphoma (rx effect?).

14
Q

What is the clinical appearance of SLE? (3)

A

Red scaly patches on sun exposed areas.
Alopecia.
Butterfly rash on cheeks + nose.

15
Q

What is seen on microscopic examination off skin from SLE? (3)

A

Thin + atrophic epidermis.
Inflammation + destruction of appendages.
IgG deposition on BM - immunofluorescence.

16
Q

How does dermatomyositis affect the skin?
Microscopically?
Associated with?

A

Heliotropic rash.Erythema in photosensitive distribution.
Lots of dermal mucin.
25% have visceral cancer.

17
Q

Differentiate between pemphigus and pemphigoid.

A

Pemphigus: intraepidermal bullae.
Pemphigoid: subepidermal bullae.

18
Q

What is pemphigus caused by?

A

Loss of cohesion between keratinocytes, causing intraepidermal blister. Autoantibodies directed against intercellular material.

19
Q

Skin appearance in dermatitis herpetiformis?
Who?
Microscopically?

A

Small, intensely itchy blisters.
Young women, often coeliacs.
IgA deposition in dermal papillae. Neutrophil microabscesses.

20
Q

Appearance of Necrobiosis Lipoidica?

Associated with?

A

Red + yellow plaques on legs.

Diabetes mellitus.

21
Q

Appearance of Erythema Nodosum?

Associated with?

A

Red tender nodules on shins.

Lung infections, drugs.

22
Q

Appearance of Acanthuses Nigricans?

Associated with?

A

Dark warty lesions on armpits.

Internal malignancy.

23
Q

What is Porphyria Cutanea Tarda caused by?
Precipitators factors? (2)
Appearance? (2)

A

Uroporphyrinogen decarboxylase deficiency. Porphyrin build up causes skin damage on exposure to sunlight.
Alcohol, Hep C.
Blisters + scarring.

24
Q

What are porphyrias?

Clinical features? (3)

A

Group of disorders caused by defective synthesis of haem.

Abdo pain, psychiatric disturbances, skin lesions.

25
Q

What is the aetiology of basal cell carcinoma? (4)

A

Sun exposed site, especially face.
Pale skin.
Immunosuppression.
Gorlin’s syndrome.

26
Q

Appearance of basal cell carcinoma -
Macroscopically:
Microscopically:

A

Nodule, later transforms into ulcer.

Islands of baseloid cells with peripheral palisade.

27
Q

Behaviour of basal cell carcinoma?

A

Malignant.

Metastases very rare.

28
Q

Risk factors for squamous cell carcinoma: (6)

A
UV radiation.
Hydrocarbon exposure.
Radiotherapy.
Chronic scars/ulcers.
Immunosuppression (esp renal transplant).
Drugs (melanoma drugs).
29
Q

Appearance of squamous cell carcinoma -
Macroscopically:
Microscopically:

A

Nodule with ulcerated + crusted surface.

Invasive islands and trabeculae of squamous cells showing cytological atypia.

30
Q

Metastases behaviour of squamous cell cancer?

A

Metastases in 5%, risk if:
Lip, ear, perineum.
> 2cm, > 4mm thick, high grade.

31
Q

What is actinic keratosis?
Appearance?
Behaviour?

A

Pre-malignant stage of SCC.
Dysplasia. Common in sun exposed areas.
Scaly lesion with erythematous base.
Rarely develops further, may resolve.

32
Q

Where do melanocytes derive from?

A

Neural crest.

33
Q

What are naevi?

A

Local benign collections of melanocytes.

34
Q

What is dysplastic naevus syndrome?

A

Multiple clinically atypical moles with atypical histology.

Increased risk of melanoma.

35
Q

What is the appearance of a melanoma? (4)

A

Asymmetrical.
Borders uneven.
Colour variation.
Larger than 6mm.

36
Q

What are the risk factors for melanoma? (4)

A

Short, intermittent sun exposure.
Race - celts at high risk (pale).
Dysplastic naevus syndrome.
Giant congenital naevi.

37
Q

What is lentigo maligna?
Who?
Microscopic?
Risk?

A

Slow growing pigmented patch.
Elderly.
Proliferation of atypical melanocytes along basal layer of epidermis + marked sun damage.
May invade dermis + metastasise.

38
Q

Where does acral lentigo maligna develop?
Who?
Miscroscopic?

A

Palms and soles.
Afro-carrribeans.
Proliferation of atypical melanocytes along basal layer of epidermis, no sun damage.

39
Q

Appearance of superficial spreading melanoma:
Microscopic:
Genetics:

A

Flate macule, develops into blue/black nodule.
Atypical melanocyte proliferation invading epidermis + dermis.
BRAF.

40
Q

What is the appearance of a nodular melanoma?

Prognosis?

A

Pigmented nodules ± ulceration.

Poor.

41
Q

What is used to determine the prognosis of melanomas? (3)

A

Breslow thickness (microscopic distance from granular layer to of epidermis to base of tumour).
BANS (back, arms, neck, scalp) - poor.
Sentinel node.

42
Q

How are melanomas treated?

A

Surgery (primary and sentinel node).

BRAF inhibitors.

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