Bullous disorders Flashcards Preview

Dermatology > Bullous disorders > Flashcards

Flashcards in Bullous disorders Deck (18):
1

Name a few causes of intraepidermal blistering?

Pemphigus
Acute dermatitis
Herpes Simplex

2

Name 2 causes of subepidermal blistering

Bullous Pemphigoid
Dermatitis Herpetiformis

3

What does bullous pemphigoid look like?

Large tense bullae on normal skin or an erythematous base.

Most cases are in people aged >60yrs.

4

When the bullae burst in pemphigoid, what is left behind?

Erosions (not scarring)

5

How does the pre-bullous phase present in bullous pemphigoid?

Itchy erythematous plaques and papules may be the presenting feature.

6

What is Nikolsky's sign?

Your health care provider may use a pencil eraser to test for Nikolsky sign. The eraser is placed on your skin and gently twirled back and forth. If the test result is positive, a blister will form in the area, usually within minutes. A positive result is usually a sign of a blistering skin condition.

Bullous pemphigoid is Nikolsky sign NEGATIVE.

7

What does immunofluorescence show in Bullous pemphigoid?

linear IgG + complement deposited around the BM

8

Treatment of localised and generalised bullous pemphigoid?

Localised - Topical steroid

Generalised - oral steroid (prednisolone 40-80mg per day)
- Tetracyclines
- Azathioprine

9

Prognosis of bullous pemphigoid?

Chronic and self limiting
Most patients achieve remission in 3 - 6 months.

10

Pemphigus vulgaris (turn over)

Incidence ranges from <1 – 5 new cases per million per year
Usually a disease of middle age

Flaccid vesicles/bullae on scalp, face, axillae, groins
Lesions rupture – raw, denuded erosions
Nikolsky sign POSITIVE

Oral lesions (80%) (painful erosions)
Erosions of vulva, conjunctivae, pharynx, larynx, oesophagus, rectum

11

How does pemphigus vulgaris present on immunofluorescence?

- "chicken wire" pattern
- IgG antibodies are directed against intercellular adhesions.

- Common to all variants of pemphigus is the process of acantholysis = lysis of intercellular adhesion sites

12

Prognosis of pemphigus vulgaris?

Most cases remit within 3 - 6 years.

Mortality rate 10-20% even in patients who are treated.

13

Who does dermatitis herpetiformis affect?

Affects all ages, majority of patients are young adults.

14

Dermatitis herpetiformis associations?

There may be a family history of DH or a personal history of Coeliac disease

15

What sites are involved in dermatitis herpetiformis?

- extensor aspects elbows and forearms
- buttocks and scapulae
- extensor aspects of knees
- face and scalp

16

Clinical features of dermatitis herpertiformis?

- Small blisters on an erythematous urticarial base.
- Itch usually precedes blistering.
- Excoriations.
- Grouping of lesions.
- Mucous membrane involvement is rare!!

17

Immunofluorescent appearance of dermatitis herpetiformis?

sub-epidermal bullae with granular IgA in dermal papillae

18

Coelic serology?

IgA antibodies to tissue transglutaminase (tTG)