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vesiculo bullous lesions
V-B lesions can be classified as:
Primary e.g. Pemphigus
Secondary e.g. physical, chemical burn
Most primary causes of V-B lesions are?
Give examples immunobullous disorders PPLED?
Give eg.s of congenital causes:
They result from?
Loss of attachment between cells (intraepi) or between cells and CT (sub-epi)
What are most V-B disorders?
EXCEPT pemphiGUS Vulgaris and viral infections
EM can have both
Of the intra-epi lesions, name the two mechanisms?
Pemphigus - acantholytic (breaks down the attachment apparatus desmosomes)
Viral - non acantholytic (cell death)
Most common Vulgaris (70%)
Who gets Pemphigus?
Clinical fts Pemphigus:
SKIN - limbs, trunk, genitalia, lip and nose crusting
MUCOSA - Blisters, become erosions, desquamative gingivitis, +Nikolsky�s sign
Other mucosa, e.g. conjunctiva
Histopath of Pemphigus:
Inta-epi bulla produced by acantholysis
Tzank cells in vesicle fluid
Rupture of vesicle - ulcer with inflamm infiltrate in floor
DIF - IgG to intra-cellular epi
IIF - (serum)- increase titre of circulating antibodies Desmoglein 3 (and some pts Desmoglein 1)
How can you monitor the condit?
Increase titre indicates increased severity
Treatment of pemphigus?
Steroids eg. 80-100g/day
and Azathioprine - allow steroid dose to be lower
Screen pts before giving Aza, they might have an enzyme breaking it down
Consult dermatologist, opthamologist
Paraneoplastic pemphigus is assoc with?
partic lymphomas and leukaemia
Usually resolves if cancer resolves
Pemphigoid, 2 major clinical types?
Bullous Pemphigoid - SKIN
MMP - Mucosal (skin rare)
Who gets MMP?
Similar to Pemphigus, Middle aged, female
Name some of the mucosal surfaces affected:
What do they get with MMP?
Bullae/erosions (if ruptured)
Can be blood filled
Erosions are longer lasting, persistent, slow to heal, fibrinous base
Dequamative ging common
May have +Nikolsky
Histo of MMP?
Sub epi bullae
The epi forms roof of bullae
CT is floor
CT infiltrated with inflamm
Investigations for MMP
DIF - binding of anti C3/ IgG/M to BM
IIF - generally low levels of Autoantibodies, can be -ve even!
Treatment of MMP?
Mild - topical steroids
Mod-severe - dapsone, prednis + azathioprine
Is MMP fatal?
No, but has a chronic course, can lead to blindness, therefore Tx as early as poss.
Complications of MMP:
Blindness from conjuntival scarring
Laryngeal scarring - stenosis
Oesophageal scarring - stricture
MMP diff dx?
Angina bullosa haemorragica
Linear IgA name 4 fts?
Very similar to MMP
Oral and occ
DIF linear deposition of IgA at BMZ
Dermatitis Herpetiformis 4 fts?
Rare, usually assoc with Coeliac
Skin - pruritic rashes at elbow, knees
OM in only 10% pts (bullae, desquamitive ging�)
What is Erythema multiforme?
Acute, often recurrent, HYPERSENSITIVITY REACTION.
Possible causes of EM?
Drug reaction eg. Anticonvulsants, barbituates, sulphonamides, antibiotics
Infection eg. H. simplex
Other eg. Preg, malig
Who gets it?
Younger people 20-40yo
20% in children
Describe the spectrum of clinical fts of EM:
Minor - affects only 1 site, not debilitating
Major - widespread, life threatening, Steven-Johnson syndrome
What is EM often characterised by?
Serosanguinous exudates of the lips
Target lesions on skin
Rashes in EM can vary, describe:
Patchy erythema to target lesions and bullae
What makes you think viral infection as a differential?
Prodromal symps may be experienced
Steven-Johnson syndrome involves which sites?
Skin + 2 or more mucosal lesions
Oral lesions of SJS?
Widespread irreg fibrin covered erosions
Diffuse and widespread macules that progress to blisters and ulceration
Lips - swollen, cracked, bleeding, crusting, drooling
Recurrence. Lasts 10-20days
Skin lesions of SJS?
Macules/Papules - pruritic or erythematous
Large target lesions - centre is a necrotic ulcer
If very severe, large skin bullae - Toxic Epidermal necrolysis
Other mucosa in SJS?
Eyes - lacrimation, redness, bloodshot, conjunctivitis, adhesion of eyelid to eyeball
Dx of EM?
Biopsy - Variable histopatho - sub and intra epi
Fluids, Nutrients if anorexia