Ch 8 Reactive Erythema and Vasculitis

Question 1

Urticaria and Cause

Answer 1

• Less than 24 hours (except delayed pressure)
• capillary permiability
• Lasts greater than 6 weeks is considered chronic

Question 2

Causes Overall

Answer 2

• Aspirin
• IgE
• Physical

Question 3

Physical Urticarias

Answer 3

• Cold
• Hot
• Solar: Tx with beta carotene, erythrodermic porphyria, IgE
• Pressure
• Delayed Pressure - Lasts greater than 24 hours
• Cholinergic - Tranquelizers
• Dermatographism

Question 4

Hypersensitivity

Answer 4

• IgE to something leads to realease

- The I’s

Question 5

Pharmacologic

Answer 5

-Aspirin
-ACEI
Morphine

Question 6

Contact

Answer 6

IgE mediated, but absorbed through skin

-Plants, bugs, Latex (Brazilenses)

Question 7

Urticaria Dx

Answer 7

• As above + (important that urticaria is less than 24 hrs)
• EM
• Begining of bullous diseases
• Urticarial Vasculitis
• insects have central punctum

Question 8

Other Causes

Answer 8

• Infection
• Parasite
• Hyperthyroidism
• Hypereosinophils
• Cancer (lymphoma)

Question 9

Tx Urticaria

Answer 9

• Antihistamines

- Solar give beta carotene

Question 10

Hereditery Angioedema

Answer 10

• AD loss of C1 esterase
• Decreased C4 levels
• Angioedema of mucous membrane interface, most commonly following trauma
• Tx is chronic androgenic steroids

Question 11

Erythema Multiforme Presentation and Histology

Answer 11

• Annular raised plques with central clearing
• Most commonly on palms and soles
• SJS when involves mucous membranes and fever
• Last 1-2 weeks (longer than 24 hours)
• Histology shows epidermal and dermal necrosis, endothelial swelling, perivascular infiltrate and papillary edema

Question 12

Causes of EM

Answer 12

HSV, Hep B/C, Drugs, Pregnancy, Mycoplasma, Orf, Cocci, parasites, malignancy, radiation

Question 13

Tx

Answer 13

• Identify cause

- SJS give IVIG, treat like burn, watch eyes and airway

Question 14

Erythema Nodosum

Answer 14

• Paniculitis most commonly on the shin
• Generally bilateral (Dif from infection)
• Painful nodules
• Leprosum will have fever and other signs
• Associated with Mycoplasma, Sarcoid, Hep B/C, Preg, Drugs, Ca, Bechets, Inflammatory Bowel, OCP, Sulpha
• Tx: Cause, Pottasium Iodide, NSAIDs

Question 15

Acute Febrile Neutrophilic Dermatosis

Answer 15

• Neutrophils in dermis and epidermis lead to erythematous nodules
• Cause: Malignancy (AML), drugs (GMCSF), Bechets

Question 16

Vasculitis

Answer 16

Defined by fibrinoid necrosis

Question 17

Leukocytoclastic/allergic/anaphylactoid

Answer 17

• Ag/Ab complex deposit leading activation of complement, neutrophils and necrosis
• Palpabable painful purpura in dependent areas
• HSP
• Can have an urticarial component (greater than 24 hours)
• Decreased Complement
• Check renal function
• DDX: coags and sepsis (Painful and palpabls)
• Tx: Colchicine/Dapsone

Question 18

Polyarteritis Nodosa

Answer 18

• Necrotizing vasculitis of large arteries
• Leads to infarction, gangrene, ulceration in linear pattern
• Can see livedo reticularis
• Cause: Hep B/C, Drugs, B Cell lymphoma
• Decreased C4
• Vessels will show dilation and necrosis
• Check renal function
• Must remove cause to treat
• DDX: Embolism, panniculitis, Wegners
• Steroids or cyclophosphamide

Question 19

Wegners

Answer 19

• Mostly lungs and nasal
• 50% have skin findings
• Treat with cyclophosphamide and steroids
• cANCA