Acute Inflammatory Dermatoses - Westra Flashcards
Remember that we don't need to get caught up in the histopathology and other details. Dr Westra just wants the important points and things that differentiate the different pathologies
How does Urticaria present?
Transient, raised erthematous wheals
IgE and histamine mediated
Pruritic (itchy)
Often has to do with medication or some other new type of exposure
How does angiodema present?
Swelling of the deep dermal and subcutaneous layers
Burns + Painful
Common on eye, lip, groin, palms/soles
Laryngeal invovlement = emergency!
What causes angiodema and urticaria?
I Immune A. Type I IgE Mediated B. Auto-immune C. Infectious II Non-Immune A. Physical Urticarias B. Direct mast-cell degranulation C. Foods containing high levels of histamine
What can stimulate an immune urticaria or angioedema?
Foods (shellfish/peanuts/eggs/soy/wheat/etc Latex Insect stings Meds Aeroallergens (pollens, molds, etc)
What are some examples of non-immune physical urticarias?
solar cholinergic (sweating) cold dermographism (write on yourself) aquagenic Vibration pressure
What are examples of stimulation of Direct Mast Cell Degranulation (NON-IMMUNE)?
Narcotics Aspirin NSAIDS Radiocontrast Dextran ACE inhibitor Vanco!
What kinds of foods have a lot of histamine?
Would this create an immune or non-immune urticaria or angioedema reaction?
Strawberries Tomatoes Shrimp Lobster Cheese Spinach Eggplant
IT WOULD BE NON-IMMUNE!!!!!
What is the general therapy for these two problems?
Dont get too crazy here people!
- Avoid the problem allergen/stimulant
- Antihistamines, esp. non-sedating H1-blockers
- Most can also improve on their own
What are the distinguishing traits of erythema multiform?
erythematous iris-shaped papular and vesiculobullous lesions
Generally seen in extremeties
3 major causes of erythema multiforme?
Drugs (mainly sulfonamides)
Infection from herpes simplex or mycoplasma
Idiopathic (big fat question mark)
***Generally the minor form is caused by Herpes Simplex, while the major and more severe form is caused be drugs reactions and mycoplasma infection
When do we see erythema mutliforme turn into Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis?
In both, 2 or more different mucosal membranes must be affected
Over 10% epidermal detachment becomes Stevens-Johnson
About 30% epidermal detachment considered Toxic Epidermal Necrolysis
What is the key feature of a fixed drug eruption?
sharply demarcated erythematous patch (could itch or burn) that heals hyperpigmented
Caused by drug
What is panniculitis erthema nodosum?
Erythematous tender nodules typically on anterior shins
triggered by infection, meds, or autoimmune
What is panniculitis erthema Induratum?
Tender erythematous nodules often seen on posterior legs
Associated with TB
