1. Define
1.1. A spectrum of Inflammatory skin reaction
1.2. Induce by exposure to external substance
1.3. and mainifests with
1.3.1. erythematous
1.3.2. vesicular
1.3.3. Papular
1.3.4. or lichenifed pruritic rash
2. Types
2.1. Allergic CD
2.1.1. Pathophysiology
2.1.1.1. Type VIa and c
2.1.1.2. Ag conjugated w/ protein in skin
2.1.1.3. Keratinocytes-->cytokines
2.1.1.4. Langerhans present Ag on MHC 1 to T-cell
2.1.1.5. T-cell-->pro inflammatory cytokines
2.1.1.6. subsequent exposure, specific T-cell move from LN to systemic circulation to the exposed skin site -->inflammation (process take 12-36hrs)
2.1.2. Skin thickness & integerity
2.1.2.1. Thiner sites are more vulnerable
2.1.2.1.1. eyelids
2.1.2.1.2. earlobes
2.1.2.1.3. genital skin
2.1.2.2. Thick skin more resistent
2.1.2.2.1. Palms
2.1.2.2.2. Soles
2.1.3. Location
2.1.3.1. Hands 30%
2.1.3.2. Face 15%
2.1.3.3. Generalized 15%
2.1.3.4. 5%
2.1.3.4.1. Eyelids
2.1.3.4.2. Trunk
2.1.3.4.3. Feet
2.1.4. Patch testing
2.1.4.1. Cresendo phenomena
2.1.4.1.1. Peaked reaction between 1st and 2nd reading
2.2. Irritant CD
2.2.1. Key points
2.2.1.1. The most common (80%)
2.2.1.2. In any person if applied in sufficient concentration & time
2.2.1.3. may precede the development of ACD
2.2.1.4. No previous sensitization required
2.2.1.5. Stinging more than pruritic
2.2.1.6. Decresendo phenomena
2.2.1.6.1. PT reaction decreases between 1st & 2nd reading
2.2.2. Pathophysiology
2.2.2.1. Direct, nonspecific tissue activation
2.2.2.2. T-cells
2.2.2.2.1. TNF-a
2.2.2.2.2. IL-1
2.2.2.2.3. IL-8
2.2.2.2.4. GM-CSF
2.2.3. How?
2.2.3.1. Acid
2.2.3.1.1. Coagulate epidermal protein
2.2.3.2. Oxidant
2.2.3.2.1. Change the epidermal intergerity
2.2.3.3. Solvents
2.2.3.3.1. Remove the lipid protection of the surface
2.2.4. Etiology
2.2.4.1. Bodily fluids
2.2.4.1.1. Saliva
2.2.4.1.2. Urine
2.2.4.1.3. Stool
2.2.4.2. Environmental factors
2.2.4.2.1. Washing
2.2.4.2.2. Overhydration
2.2.4.2.3. Improper drying
2.2.4.2.4. Persipiration
2.2.4.2.5. Temperature extreme
2.3. Photoreaction
2.3.1. Types
2.3.1.1. Allergic
2.3.1.1.1. AKA photoallergic
2.3.1.2. Irritant
2.3.1.2.1. AKA phototoxic
2.3.2. Etiology
2.3.2.1. For both
2.3.2.1.1. NSAIDs
2.3.2.1.2. Diuretics
2.3.2.2. Photoallergic
2.3.2.2.1. PABA
2.3.2.2.2. Chlorhexidine
2.3.2.2.3. Dapson
2.3.2.2.4. Sulfonylurea
2.3.2.3. Phototoxic
2.3.2.3.1. Psoralen
2.3.2.3.2. Meds
2.3.2.3.3. Food
2.4. Contact Urticaria
2.4.1. Types
2.4.1.1. IgE-mediated
2.4.1.1.1. Food
2.4.1.1.2. Meds
2.4.1.1.3. Other
2.4.1.2. Non IgE mediated
2.4.1.2.1. Fragrances
2.4.1.2.2. arthropods المفصليات
2.4.1.2.3. jellyfish
2.4.1.2.4. coral مرجان
3. Top 10 Chemical Allergens
3.1. Metal
3.1.1. Nickel sulphate
3.1.1.1. Jewellery
3.1.1.2. Coins
3.1.1.3. Snaps
3.1.1.4. Button
3.1.1.5. Nickel
3.1.1.5.1. Use DiMethylGlyoxime test
3.1.1.6. It can cause systemic dermatitis (if pt ingest >2mg of nickel /day
3.1.1.6.1. Lentil, soybean, cashew contain nickel
3.1.2. Cobalt Chloride
3.1.2.1. Present
3.1.2.1.1. Dental
3.1.2.1.2. Artificial joints
3.1.2.2. Second allergen in metal is cobalt chloride just after nickel
3.1.3. Chromate and dichromate
3.1.3.1. Textile and steel
3.1.4. Sodium Gold thiosulphate
3.2. Antibiotics
3.2.1. Neomycin
3.2.1.1. Cream
3.2.1.2. Ointment
3.2.1.3. Eye drop
3.2.2. Bacitracin
3.2.2.1. It is the only one can cause immediate IgE reaction
3.3. Fragrances
3.3.1. Balsam of Peru
3.3.1.1. Fragrances
3.3.1.2. Pharmacetuical
3.3.1.3. Flavouring agent
3.3.2. Fragrances Mix 1
3.3.3. Fragrances Mix 2
3.4. Preservative
3.4.1. Formaldehyde
3.4.2. Quaternium-15
3.4.3. Thimersol
3.4.3.1. It is a preservative
3.4.3.1.1. Contact lens
3.4.3.1.2. Vaccines
3.4.3.1.3. Cosmetics
3.4.3.1.4. Topical meds
4. Top Planet Allergen
4.1. Plant
4.1.1. Allergen in most plant is the Oleoresin
4.1.1.1. Substance in plant composed of resin and oil
4.1.2. Toxicodendrone dermatitis
4.1.2.1. AKA
4.1.2.1.1. Poison Ivy
4.1.2.1.2. Poison Oak
4.1.2.1.3. Poison Sumac
4.1.2.2. The most common form of plant ACD
4.1.2.3. Allergen
4.1.2.3.1. Urushiol
4.1.2.4. Clinical
4.1.2.4.1. May occur after years of exposure
4.1.2.4.2. 85% of population will react. 15% will have systemic symptoms (rash, swelling of face and genital
4.1.2.5. Cross-reactivity
4.1.2.5.1. Mango peel
4.1.2.5.2. Fruit of the cashew
4.1.2.5.3. Ginkgo biloba
4.1.2.6. Treatment
4.1.2.6.1. Never patch test for toxicodendrone because they can severe ulcer bullos reactions!
4.1.2.6.2. Education about how the plants look like and other cross reacting plant and food
4.1.2.6.3. Wearing long cloths
4.1.3. Flower worker
4.1.3.1. Alstromeria (Peruvian Lily)
4.1.3.1.1. Allergen is Tulipan-a
4.1.3.1.2. Pruritic dermatitis on
4.2. Exam Q: list 8 points about contact dermatitis in gardner
4.2.1. Plant
4.2.2. Metal
4.2.2.1. Remember Potassium dichromate present in leather (e.g. leather gloves)
4.2.3. Preservative
4.2.3.1. Formaldyhyade
4.2.3.2. Quaternium
4.2.4. Rubber
4.3. Resins
4.3.1. Epoxy
4.3.1.1. Present in
4.3.1.1.1. Adhesive
4.3.1.1.2. Composite materials
4.3.2. Colophony
4.3.2.1. Comes from different Pine trees
4.3.2.2. Present in
4.3.2.2.1. Cosmotics
4.3.2.2.2. Topical medications
4.3.2.2.3. Industrial products
4.3.2.3. Different pine tree will give different colophony and hence need different agent in patch testing!
4.3.2.4. Cross-React with
4.3.2.4.1. Balsam of Peru
4.3.3. Ethylenediamine dihydrochloride
4.3.3.1. Present in
4.3.3.1.1. creams
4.3.3.1.2. aminophylin
4.3.3.1.3. nystatin
4.3.3.1.4. Piperazine based antihistamine
4.3.3.2. If sensitive to ethylenediamine dihydrochloride, avoid product that contain it as above
4.3.3.3. No cross-reactivity with
4.3.3.3.1. EDTA Ethylendiaminetetra acetic acid
4.3.4. Paraphenylendiamine
4.3.4.1. Epidemic in henna
4.3.4.2. Pts are Not allergic to henna but allergic to PPD in it.
5. Site of body
5.1. Hands
5.1.1. Most common
5.1.2. If solar of wrist involve-->think about AD (isolated or contributed factor for CD)
5.1.3. Involve thinn skin-->dorsum especially finger tips
5.1.4. ACD present with vesicles finger tips and nail folds and dorsum of the hands
5.1.5. ICD
5.1.5.1. No vesicles
5.1.5.2. Webs of the fingers extends onto dorsum & ventral surface in an apron pattern
5.2. Eyelids
5.2.1. 1 Dx ACD
5.2.1.1. #1 Ax
5.2.1.1.1. Cosmetics
5.2.2. Very sensitive skin
5.2.2.1. substance on the scalp or face come in contact.
5.2.3. DDx
5.2.3.1. Pollen or dust allergy have prominent palpebral conjunctivitis
5.2.3.2. ACD
5.2.3.2.1. 50-75% of pts w/ eyelids dermatitis
5.2.3.2.2. Eespically if B/L upper and lower eyelids involvement
5.2.3.2.3. allergens
5.2.3.3. ICD
5.2.3.4. AD
5.2.3.5. Seborrheic dermatitis
5.2.4. Cause
5.2.4.1. Allergen
5.2.4.1.1. Metal
5.2.4.1.2. Preservative
5.2.4.1.3. Fragrances
5.2.4.1.4. Remote syte
5.2.4.1.5. Hair dye
5.2.4.1.6. Inhalent allergen
5.2.4.2. Irritant
5.2.4.2.1. Sweating
5.3. Face
5.3.1. similar to eyelids, can be from application in other body parts
5.3.2. allergens
5.3.2.1. moisturizers
5.3.2.2. suncreens
5.3.2.3. foundations
5.3.2.4. powder products
5.3.2.5. Hair products
5.3.2.5.1. scalp skin is resistant to allergens in shampoo and hair dye
5.3.2.6. rubber sponges, mask or ballons
5.3.2.7. Spouse's fragrances
5.3.2.7.1. atypical unilateral facial eruptions
5.4. Perioral dermatitis
5.4.1. Evaluate for both ICD and ACD
5.4.2. If chronic mucosal inflammation-->think other than ACD
5.5. Mucus membrane
5.5.1. Present w/ recurrent ulcerations
5.5.2. Physical exam
5.5.2.1. barely visible
5.5.2.2. mild erythema +/- edema
5.5.3. Allergens
5.5.3.1. dental and mouth care products
5.5.3.2. The most common (chewing gum and dentifrices معجون)
5.5.3.2.1. Cinnamon
5.5.3.2.2. Pepermint
5.5.3.3. Orthodontics
5.5.3.3.1. Nickel
5.5.3.3.2. Mercury
5.5.3.3.3. Chromate
5.5.3.3.4. Gold
5.5.3.3.5. Cobalt
5.5.3.3.6. Beryllium
5.5.3.3.7. Palladium
5.6. Generalized, scattered dermatitis
5.6.1. Difficult to diagnose as ACD
5.6.2. Allergen
5.6.2.1. Nicekl
5.6.2.2. Balsam of Peru
5.7. Anogeneital region
5.7.1. Irritant
5.7.2. Allergen
5.7.2.1. #1 meds
5.7.2.1.1. Topical steroid (use for irritation)
5.7.2.1.2. Topical antibiotics
5.7.2.2. Metal
5.7.2.2.1. Nickel
5.7.2.2.2. Cobalt chrloide
5.7.2.2.3. Chromate
5.7.2.2.4. Dichromate
5.7.2.3. Preservatives
5.7.2.3.1. Wipes
6. Patch Testing
6.1. Indicated
6.1.1. in any patient with
6.1.1.1. Chronic pruritic
6.1.1.1.1. recurrent eczematous or
6.1.1.1.2. lichenified dermatitis
6.2. Kits
6.2.1. Smart Practice Canada
6.2.1.1. Alberta
6.2.2. T.R.U.E
6.2.2.1. Thin Layer Rapid Use Epicutaneous Test
6.2.2.2. FDA approved
6.2.2.3. 29 allergens
6.2.2.4. High false negative
6.2.2.4.1. Neomycin
6.2.2.4.2. Thiuram mix
6.2.2.4.3. Fragrances
6.2.2.4.4. Balsam of Peru
6.2.2.4.5. Lanolin
6.2.2.4.6. Cobalt
6.2.3. North America Contact Dermatitis Series
6.2.3.1. 70 allergens
6.2.3.2. Relevant to North America
6.2.4. European Stander Series
6.2.5. International
6.2.6. Japanese
6.2.7. Kit of specific exposure
6.2.7.1. Hairdressers
6.2.7.2. Bakers
6.2.7.3. Shoes
6.2.7.4. Plants
6.2.7.5. Photo allergens
6.2.7.6. Dental
6.2.7.7. Textiles
6.2.7.8. Metal
6.2.7.9. Medicaments
6.2.7.10. Sunscreens
6.2.7.11. Corticosteroids
6.3. Source
6.3.1. AllergEAZE.come
6.3.2. Dormer.com
6.3.2.1. Ontario, Canada
6.4. Or make the allergen
6.4.1. Personal product
6.4.1.1. Those apply as is
6.4.1.1.1. Apply directly on the back in a chamber
6.4.1.2. Wash-off products (shampoo, soap)
6.4.1.2.1. Dilute 1:10 to 1:1,000
6.4.2. House hold products
6.4.2.1. Dilute 1:100 to 1:1,000 dilution
6.4.3. Clothing, gloves, plant
6.4.3.1. Apply as is
6.4.4. Industrial
6.4.4.1. Great Caution
6.4.4.2. Employer to bring an MSD (Material Safety Data)
6.4.4.2.1. Review the toxicity
6.4.4.2.2. Effect on skin
6.4.4.3. Never use something that has no label or unknown origin on testing
6.5. Reading the test
6.5.1. Medication
6.5.1.1. Anti-histamine do NOT interfere!
6.5.1.2. Steroid if 20mg of more interfere with the test
6.5.1.2.1. Deferred until off or below 20 mg
6.5.1.3. High dose topical corticosteroid can interfere with the result
6.5.1.3.1. Stop them from PT site 7 days prior
6.5.2. Allergen that will be positive beyond 5 days
6.5.2.1. Metal
6.5.2.1.1. Gold
6.5.2.1.2. Potassium dichromate
6.5.2.1.3. Nickel
6.5.2.1.4. Cobalt
6.5.2.2. Topical abx
6.5.2.2.1. Neomycin
6.5.2.2.2. Bacitracin
6.5.2.3. Topical corticosteroid
6.5.2.3.1. Day 7!
6.5.2.4. PPD
6.5.2.4.1. Para-phenylenediamine
6.5.3. Most will be positive by 48hrs.
6.5.3.1. 30% will be only positive after 72hrs
7. Managment
7.1. Corner Stone
7.1.1. Avoidance (CAMP)
7.1.1.1. Provide to the patient the Contact Allergen Management Program (CAMP)-->show list of safe product that don't contain the allergen
7.2. Supportive
7.2.1. Cool compresses
7.2.2. Avoid topical diphenhydramine (benadryl)
7.2.2.1. risk of cutaneous sensitization
7.2.3. Use nonsenszitizing and fragrance free emollients
7.2.4. Other solutions
7.2.4.1. Burrow solution
7.2.4.2. Calamine
7.2.4.3. Oatmeal baths
7.2.5. Garments contain formaldehyde
7.2.5.1. Wash before use
7.3. Immunosuppresive med
7.3.1. Topical steroid
7.3.1.1. First line medical Rx.
7.3.1.2. Low potency in thin skin
7.3.1.2.1. Face
7.3.1.2.2. Eyelids
7.3.1.3. High potency
7.3.1.3.1. chronically thickened skin
7.3.1.4. Ointments have greater penetrance
7.3.1.4.1. Contain lower sensitizers
7.3.2. Systemic steroid
7.3.2.1. Severe cases
7.4. Oral antihistamine
7.4.1. Offer minimum relief of the pruritus in CD
7.4.2. Avoid diphenhydramine in patients with CD to
7.4.2.1. Diphenhydramine in a clamine base (Caladryl)
7.4.3. Avoid Atarax (hydroxyzine)
7.4.3.1. in patients with ethylenediamine sensitivity
8. Systemic Contact Dermatitis
8.1. Causes
8.1.1. Metal
8.1.1.1. Nickel
8.1.1.2. Gold
8.1.1.3. Mercury
8.1.2. Medications
8.1.2.1. Aminoglycoside
8.1.2.1.1. if someone has CD to neomycin and get systemic amino glycoside-->systemic dermatits
8.1.2.2. Corticosteroids
8.1.3. Fragrances
8.1.3.1. Balsam of Peru
8.2. Baboon Syndrome
8.2.1. Symetrica
8.2.2. Involve the folds
8.3. Angry Back Syndrome AKA Excited Skin Syndrome
8.3.1. Due to strong true positive reaction to one allergen, the whole back become hyper-reactive and would have false reaction to other agents tested
8.3.1.1. Not reproducible
8.3.1.2. Occur ~ 5% of PT
9. Other
9.1. Cosmotics
9.1.1. Fragrances
9.1.1.1. The most common culprit in comsmotics
9.1.1.2. Balsam of Peru is # 1
9.1.1.2.1. Cross-Reactivity
9.1.2. Preservatives
9.1.2.1. Formaldehyde donors
9.1.2.1.1. high prevalence in PT 8%
9.1.2.1.2. Quaternium-15
9.1.2.2. Nonformaldehyde donors
9.1.2.2.1. Parabens
9.1.3. Excipients
9.1.3.1. These are inert substance that serve to
9.1.3.1.1. solubilize
9.1.3.1.2. thicken foam
9.1.3.1.3. Lubricate
9.1.3.1.4. or coloring the substance
9.1.3.2. There are table for the most common excipients
9.1.4. Hair products
9.1.4.1. Second to skin care cosmoteic as a cause of CD
9.1.4.2. Causes:
9.1.4.2.1. Paraphenylenediamine
9.1.4.2.2. Other causes present in shampoo, eye and facial cleaner and bath products and in permenant wave solutions
9.1.5. Acrylics
9.1.5.1. Clinically
9.1.5.1.1. Present distal finger
9.1.5.1.2. Ectopically in the face
9.1.5.2. PT for multiple acrylates
9.1.5.2.1. Ethylacrylate is #1
9.1.5.3. Also think about formaldehyde containing products.
9.1.6. Glues
9.1.7. Sunblock and suncreen
9.1.7.1. Photoallergic CD
9.1.7.2. "Chemical free" sunblock uses physical blocking agents and rare to be sensitizer
9.1.7.2.1. Titanium based
9.1.7.2.2. Zinc Oxide based
9.2. Hair dressers
9.2.1. Allergen
9.2.1.1. Paraphenylenediamine
9.2.1.1.1. Also tattoo and Henna
9.2.1.2. Glycerol Thioglycolate
9.2.1.2.1. Reaction can persist even if allergen removed
9.3. Topical steroids
9.3.1. Risk factors
9.3.1.1. AD
9.3.1.2. Stasis dermatitis
9.3.1.3. Leg ulcers
9.3.2. Worsening of symptoms on treatment
9.3.3. Read PT 7 days after application (due to immunosuppressive effect)
9.3.4. 4 group of steroid
9.3.4.1. A-Hydrocortisone type
9.3.4.2. B-Triamcinolone type
9.3.4.3. C-betamethasone type
9.3.4.4. D-Hydrocortisone 17 butyrate type
9.3.5. Patient don't usually react to all the 4 classes
9.4. Topical antibiotics
9.4.1. Common drug
9.4.1.1. Bacitricin and neomycin
9.4.2. Can cause anaphylaxis and can be delayed (time for it to be absorbed from the skin)
9.4.3. Neomycin cross react with other aminoglycosides and cross react to bacitricin
9.5. Other meds
9.5.1. Topical antihistamine
9.5.2. Topical anasthetic
9.5.2.1. Benzocain: PABA (para-amino-benzoic acid)
9.5.2.1.1. In PT, you do one topical anaesthetic as they cross react.
9.5.2.1.2. If react to benzocain, give lidocaine or mepvicain as they don't cross react
9.6. Allergic Contact Chelitis
9.6.1. Lipsticks
9.6.2. Dental devices
9.6.3. Nail polish
9.6.4. Cigarette paper
9.7. Surgical Implant Dermatitis
9.7.1. Four criteria
9.7.1.1. Localized or generalized dermatitis develop after implant insertion
9.7.1.2. Resistent to treatment
9.7.1.3. Positive PT to the agent
9.7.1.4. Resolution after removal of the implant