Lecture 11: Bullae & Desquamation Disorders Flashcards
What adheres the epidermis to the dermis?
Hemidesmosomes
What is the underlying pathophysiology for pemphigus?
Autoantibodies of the IgG class
Results in acantholysis
What are the two main descriptors of pemphigus vulgaris?
- Flaccid blisters on skin
- Erosions on mucous membranes
What specific demographic is MC for pemphigus vulgaris?
Jewish/Mediterranean descent
What characterizes pemphigus foliaceus specifically?
Scaly and crusted lesions
What demographic is MC for Pemphigus Foliaceus?
Brazilian
Brazil has lots of foliage
When does pemphigus tend to occur in general age-wise?
40-60
How are the lesions of pemphigus spaced?
Scattered and discrete with a random pattern
T/F: Pemphigus vesicles and bullae are filled with blood?
False: They are filled with serous content
T/F: Pemphigus blisters are flaccid and easily ruptured, often described as weeping?
True
What is a nikolsky sign?
Dislodging or normal appearing epidermis by lateral finger pressure in the vicinity of lesions.
Where is pemphigus vulgaris MC found on the body?
- Scalp
- Face
- Chest
- Axillae
- Groin
- Umbilicus
Where does Pemphigus Vulgaris typically begin?
Oral mucosa
What happens to a person due to painful mouth lesions in pemphigus vulgaris?
Inadequate food intake
What specific symptom is not seen in pemphigus vulgaris mouth lesions?
Lack of pruiritis
+ burning/pain
What is a key distinguishing factor seen on Physical exam between pemphigus vulgaris and foliaceus?
Lack of mucosal involvement in foliaceus
How does pemphigus foliaceus typically present?
Flaccid bullae that quickly rupture, resulting in superficial erosions.
flaccid foliage
What extends to more of the body: Pemphigus vulgaris or foliaceus?
Vulgaris, which goes down to the groin region.
Foliaceus is only face, scalp, upper chest, and abdomen
How do you test for pemphigus?
- Biopsy at the edge of a blister showing (+) deposits of IgG
- Direct immunofluorescence staining (DIF) of normal appearing skin adjacent to a lesion showing IgG and C3.
You must do a biopsy + DIF/ELISA
ELISA can be done but very expensive.
What ELISA results correspond to Pemphigus Vulgaris? Foliaceus?
- (+) a-Dsg3 = PV
- (+) a-Dsg1 = PF
PV can have neg or pos Dsg1, but only 3 matters.
V is later in the alphabet, so higher desmoglein.
Had to google this, his slides seem weird here
Dsg3 means mucosal involvement
Pharm tx for Pemphigus
- Prednisone 2-3mg/kg
- Azathioprine/Mycophenolate mofetil
Both
When do you D/C prednisone for pemphigus tx?
Cessation of new blister formation and disappearance of Nikolsky sign.
Why can osteoporosis occur in pemphigus?
Chronic Steroid use
Might need Calcium/Vit D supplements
What demographic is bullous pemphigoid typically seen in?
Elderly
What is the underlying pathophysiology of Bullous pemphigoid?
Interaction of autoantibody with BP antigen.
What is the MC bullous autoimmune disease?
Bullous pemphigoid
What junction is disrupted in bullous pemphigoid?
Dermal-Epidermal Junction
What are the most initial clinical findings for bullous pemphigoid? (2)
- Pruiritis
- Urticaria and papular lesions
Lasts weeks to months
Prodrome period
Describe the classic cutaneous lesion of bullous pemphigoid and the result of its nikolsky sign (4)
- Large, tense, firm-topped bullae (not flaccid)
- Serous or hemorrhagic fluid
- Painful erosions after rupture
- (-) Nikolsky diff from pemphigous?
Where does bullous pemphigoid tend to occur?
- Axilla
- Medial thigh
- Groin
- Abdomen
- Ventral forearm
- Lower legs
No face or scalp as in pemphigus!
Are oral lesions seen in bullous pemphigoid?
Yes, but less painful and severe.
Gold standard for diagnosing bullous pemphigoid?
Biopsy of perilesional skin showing linear IgG deposits or C3 along basement membrane.
What two serologic studies can be done to diagnose bullous pemphigoid?
- DIF showing IgG antibodies (70% of pts)
- ELISA for BPAG1 and BPAG2 (highly sens and specific, but expensive?)
Most important part of treating bullous pemphigoid
Refer to derm
How is bullous pemphigoid treated?
Prednisone 50-100mg/d + Azathioprine 150mg/d
Taper once clearance starts, same as pemphigus?
Why is osteoporosis sometimes also seen in bullous pemphigoid?
Chronic steroid use
What is the underlying pathophysiology of erythema Multiforme?
Acute HSR reaction affecting skin + mucous membranes
Type IV HSR
MCC of Erythema Multiforme
HSV
What would you expect to see in erythema multiforme?
- Erythematous, papular or urticarial lesions
- Bullae later (small or large)
- Bullae can contain serous OR hemorrhagic fluid, presenting as both pruiritic and painful
How do mucosal lesions tend to present in Erythema Multiforme?
- Erosions and Ulcerations
- Specifically in the eyes, can present as corneal ulcers or anterior uveitis
T/F Erythema Multiforme does not present with constitutional symptoms?
False: presents with fever, weakness, malaise, and fatigue
T/F: Erythema Multiforme is bilateral and symmetrical?
True
What characterizes MINOR erythema multiforme?
- Little to NO mucosal involvement
- (+) vesicles, but NO bullae
- NO systemic symptoms
- NO spread past face and extremities
How is MINOR erythema multiforme treated?
- Antihistamines for pruiritis
- Topical low-dose steroids
- Antivirals if 2/2 HSV (Valacyclovir)
- Oral lesions require High dose steroid gel
What are the 3 ways to treat painful oral lesions in Erythema Multiforme?
- High dose steroid gel (fluocinonide gel 2-3x/d)
- Compound topical oral solution (Magic swizzle)
- 1:1 viscous lido/benadryl/Maalox/(+/-) dexamethasone Swish, gargle, spit
DO NOT SWALLOW
Tx of mucocutaneous lesions in MAJOR erythema multiforme?
- IVF
- Oral compound solution (Magic swizzle)
- Systemic high dose prednisone if severe
- Pain control
- Wet compresses via Burow’s solution for large erosions
- ANY OCULAR = consult oph
What helps with recurrent erythema multiforme?
Daily antivirals
But could result in secondary bacterial infection
What is the underlying pathophysiology of SJS & TEN?
Cytotoxic event destroying keratinocytes
MCC of SJS & TEN?
DRUGS
What physical exam finding might occur prior to the massive desquamation of SJS & TEN?
Skin tenderness
Generally they are extremely sick looking
What are the characteristics of the mucocutaneous lesions seen in SJS/TEN?
- Target lesions
- Rapid confluence
- (+) Nikolsky sign
If SJS spreads and causes the loss of hair and nails, what is it now?
TEN
Idk he put in parentheses
At what point is SJS/TEN an emergency?
- Fever
- HR > 120 BPM
- Sloughing of epidermis
Classify SJS, SJS/TEN, and TEN
- SJS = < 10% BSA
- SJS/TEN = 10-30% BSA
- TEN = > 30% BSA
S before T
How is SJS diagnosed?
Clinically
How is SJS/TEN managed?
- IVF
- Parenteral nutrition
- IV pain control
- Wound care via wet dressing with Burow’s
- Non-adherent dressings for the eye made of saline and erythromycin ointment
What do you want to give to SJS/TEN early on in tx?
- IV Steroids
- IVIG