Inflammatory Dermatoses Flashcards
What are the different inflammatory dermatoses
Vasculitis
Erythema multiforme
Cutaneous drug eruption
What might vasculitis results in
Increased permeability
-Edema
-Hemorrhage
-Ischemia
inflammation of the blood vessels
vasculitis
What effects will you see from vasculitis
-Petechiae
-Ecchymoses
-Erosions/Ulcerations
-Necrosis (tissue loss)
What might cause vasculitis
Idiopathic
Medication induced/ triggered
Sepsis
Rickettsial
Paraneoplastic
SLE
What distribution does vasculitis have
Extremities common
-Pinnae
-Paws/Nails
-Planum
-Tail
-Tongue
*Well-demarcated ulcerations
What are the subtypes of vasculitis
1) Proliferative thrombovascular necrosis
2) Nasal philtrum arteritis
Proliferative thrombovascular necrosis is typically isolated to the
distal pinnae
What breeds are predisposed to nasal philtrum arteritis
large breed dogs (esp St Bernards)
What does nasal philtrum arteritis have
Well demarcated erosion to ulceration
depigmented in middle of nasal planum
large breed dogs
How do you diagnose vasculitis
1) Diascopy
Blanching = inflammation (hypotension)
Non-blanching = hemorrhage
2) Biopsy
-Avoid ulceration (no epidermis)
-Surgical (deep) biopsy for edema (larger vessels
What is diascopy
Blanching = inflammation (hypotension)
Non-blanching = hemorrhage
How do you treat vasculitis
Severe:
Steroids (2mg/kg) or Cyclosporine
Mild to Moderate:
Pentoxifylline 30mg/kg BID
Tacrolimus 0.1% topically BID
Mild vasculitis (ie distal pinnae) might be able to be treated
Topically
Tacrolimus 0.1% topically BID
What causes erythema multiforme
immune mediated destruction of keratinocytes by lymphocytes
Apoptosis death
-Erythema
-Crusts
-Ulcers/Necrosis
-Target lesions but variable presentation
Vasculitis at injection site might be secondary to
Rabies vaccine
Why is it called erythema multiforme
because it has a lot of different clinical presentations
-anything with crusting
How do you diagnose erythema multiforme
biopsy - apoptosis of keratinocytes by immune mediation lymphocytes
T/F: erythema multiforme is similar disease process as SJS and TEN
False - they all have apoptosis of keratinocytes but erythema multiforme is distinct and generally less severe
What 4 diseases cause apoptosis of keratinocytes
1) DLE
2) EM
3) SJS (severe)
4) TEN (severe)
What is the most severe skin disease
Toxic Epidermal Necrolysis (TEN)
Is EM or DLE more severe keratinocyte apoptosis
EM is slightly more destruction of kertinocytes
> 50% body surface area affected with >30% of epidermal detachment (ulceration)
Toxic Epidermal Necrolysis (TEN)
> 50% body surface affected with 10-30% of epidermal detachment (ucleration)
Steven-Johnson Syndrome (SJS)
What might cause erythema multiforme
-Idiopathic
-Medication induced/triggered
-Sepsis
-Infection
-Paraneoplastic
How do you treat EM/SJS/TEN
1) Remove underlying cause
2) Topical, systemic antimicrobials
3) Prednisone-caution with SJS/TEN
4) IVIG (Fas blockade)
5) Cyclosporine (or eqiv)
How do you tell TEN from burns
Burns taget epidermis, dermis, and SQ
TEN, just epidermis (keratinocytes)
What is the distribution of cutaenous drug eruption
variable distribution
-PF
-EM
-Vasculitits
-Cross over reactions
How do you diagnose cutaneous drug eruptions
History
-Biopsy has (variable results)
Cutaneous drug eruptions generally occur from
NSAIDs
Penicillins
Cephalosporins
How do you treat cutaneous drug eruption
1) Remove underlying cause
2) Topical, systemic antimicrobials
3) Prednisone 2mg/kg, taper
4) Cyclosporine (or equiv)
5) Pentoxifylline if vasculitic component
