Derma - urticaria, bacterial skin infxns Flashcards
Urticaria/angioedema
Edema extends to deep dermis and /or subcutaneous and submucosal layers
Angioedema
Urticaria/angioedema
Circumscribed, raised, erythematous, evanescent areas involving the superficial dermis
Urticaria
Pathogenesis of urticaria and angioedema
Mast cells, basophils, eosinophils releases histamine and cytokines
Results to vascular permeability
Then extravasation of fluids and proteins
Causing edema
Acute urticaria recurs for how many days
<30d
Chronic urticaria recurs for how many days
> 30d
Wheals of acute urticaria.
Large wheals, associated with angioedema
Wheals of chronic urticaria.
Small and large wheals
Acute/chronic urticaria
IgE-dependent (with atopic background)
Acute urticaria.
Acute/chronic urticaria
Due to anti-FcR autoantibodies
Chronic urticaria
Acute/chronic urticaria
Related to alimentary agents, parasites and penicillins
ACute urticaria
Acute/chronic urticaria
Intolerance to salicylates and benzoates
Chronic urticaria
Chronic urticaria cannot tolerate
Salicylates and benzoates
Acute/chronic urticaria
Complement mediated in serum sickness-like reaction (whole blood, ig, penicillin)
Acute urticaria
Chronic urticaria common in children/adult, M/F
Adult, F
Acute/chronic urticaria
May persist for 10yrs
Chronic urticaria
Acute/chronic urticaria
Rarely persists for >24hrs
Acute urticaria
Localized urticarias
Solar
Pressure
Vibration
Cold urticaria
Immunologic urticarias
IgE-mediated urticaria
Complement-mediated urticaria
Immunologic contact urticaria
Autoimmune urticaria
Immunologic urticaria due to type 1 HPS with atopic background. Common Ag are food, drug and helminths
IgE mediated urticaria
IgE mediated urticaria HPS type
Type 1 HPS
Acute immunologic urticarias
IgE mediated
Complement mediated
Immunologic contact
Immunologic urticaria which releases anaphylotoxin causing mast cells degradation. Common in serum sickness, ig and admin of whole blood
Complement mediated urticaria
Chronic immunologic urticaria
Autoimmune urticaria
Immunologic urticaria common in children with atopic dermatitis sensitized to environmental allergens and individuals sensitized to latex rubber gloves. Accompanied by anaphylaxis.
Immunologic contact urticaria
Autoimmune urticaria is positive in what test
Autologous serum skin test
The remission of disease activity of autoimmune urticaria is due to
Plasmapheresis
IVIg
Cyclosporin
Physical urticaria with positive linear lesion after storming or scratching skin
Dermographism
Demographics fades in …
30min
Physical urticari confined to sites exposed to cold
Cold urticaria
Diagnosis of cold urticaria
Ice cube test
How to do ice cube test
Application of ice for 10min
Wheal appears within 5min
Diagnostic test for solar urticaria
Test with UVB, UVA and visible light
How to test solar urticaria
260-690nm uv expo for 30-120s
Wheal appears within 30min
Wheezing for <1hr is seen in what Physical urticaria
Solar urticaria
Mediator of solar urticaria
Histamine
Wheezing physical urticaria
Solar
Cholinergic urticaria
Physical urticaria which appears with exercise and sweating
Cholinergic urticaria
Physical urticaria in which the intracutaneous of ACH and mecholyl will produce micropapular whealing
Cholinergic urticaria
Very rare phys urticaria with water of any temperature
Aquagenic urticaria
Aquagenic urticaria lesion is same with
Cholinergic urticaria
Sites of predilection of pressure urticaria
Soles
Palms
Waist
Applications of p perpendicular to skin in pressure urticaria will produce WHEAL after..
1-4hrs
Pressure urticaria is delayed for (time)
30min-12hrs
Physical urticaria which is painful and interferes with quality of life. No lab abnormalities. Associated with fever
Pressure angioedema
Familial, autosomal dominant physical urticaria
Vibratory angioedema
Distinct angioedema syndrome
Hereditary angioedema HAE
Angioedema-urticaria-eosinophilia syndrome AUES
Major mediator of chronic idiopathic urticaria
Histamine.
Eicosanoids and neuropeptides
Urticaria due to mast cells releasing agents and pseudo allergens and chronic idiopathic urticaria
Urticaria due to mast cells releasing agents and pseudo allergens and chronic idiopathic urticaria AGENTS
FAARS Food preservatives Ace inhibitors Additive azo dyes Radio contrast media Salicylate
Due to direct effects of exogenous urticants penetrating into skin and blood vessels
Non immune contact urticaria
Urticaria associated with vascular/connective tissue autoimmune disease
SLE
Sjögren’s syndrome
Urticaria vasculitis lesion persists for
> 12-24hrs
Urticaria associated w vascular or connective tissue autoimmune disease has SLOW/RAPID changes in size and config
Slow
Urticaria associated w vascular or connective tissue autoimmune disease may or may not have residual pigmentation due to
Hemosiderin
Urticaria often with hypocomplementemia and renal disease
Urticaria associated w vascular or connective tissue autoimmune disease
HAE is autosomal dominant/recessive
Dominant
T or F: Uritacaria usually occurs in HAE
Does not usually occur
Lab abnormalities in HAE
Decreased C1-esterase inhibitor
Low C4
May follow trauma (phys/emotional)
AE of face and ext, laryngeal edema, acute abd pain (presents as surgical emergency)
With bradykinin formation
Can be life threatening
HAE
Treatment for HAE
Danazol (long term)
Whole fresh plasma
With severe AE with pruritic urticaria of face, neck, trunk and ext
AUES
AUES lasts for how many days
7-10d
Lab abnormalities of AUES
Leukocytosis
Eosinophilia
HAE/AUES:
No family history
Fever
Marked increase in wt
AUES
Treatment for AUES
Prednisone
HAE/AUES: good prognosis
AUES
Lab in urticarial vasculitis
Increased ESR
Hypocomplementemia
Flushing. Burning. Wheezing.
Cholinergic urticaria
Fever.
Serum sickness
AUES
Hoarseness. Stridor. Dyspnea.
AE