Essentials of Contact Dermatitis 2018

Transcription

1 Essentials of Contact Dermatitis 2018 Joseph F. Fowler Jr. MD Clinical Professor of Dermatology U. Of Louisville Pres. No. American Contact Dermatitis Group Disclosures Consultant and speaker, SmartPractice Inc. distributor of patch test materials Irritant Allergic Contact Dermatitis Patch Testing Techniques Common Allergens 1

2 Irritant Contact Dermatitis (ICD) No prior immunologic sensitization required Direct toxic effect on the skin May occur on first exposure and any subsequent exposure Irritant Contact Dermatitis Acids, alkalis: direct epidermal injury Soaps: defatting effects Solvents: likewise Water: excess skin hydration Friction: mechanical injury Irritant Contact Dermatitis: Classification and Causes Acute irritant contact dermatitis Contact with a concentrated acid, an alkali, salts, or solvents Cumulative irritant contact dermatitis Repetitive exposure to weaker irritants may eventually lead to dermatitis Progression of damage to the barrier function of the skin English JSC. Occup Environ Med. 2004;61:

3 Irritant Contact Dermatitis Chronic exposure to soap and water causing subacute inflammation Patients vary in their ability to withstand exposure to irritants Poison Ivy-Oak-Sumac 70% or more Americans allergic Plants almost everywhere in N.A. Leaves of 3- let it be First exposure: allergen (aka hapten) penetrates skin surface, combines with proteins, is processed by Antigen Processing Cells, Allergen carried to regional nodes T-cells are introduced to the allergen Allergen- specific T-cells proliferate This all takes about 2 weeks ACD 3

4 Future exposures: allergen uptake and presentation as before Circulating memory T-cells recognize antigen and induce immunologic cascade Dermatitis develops This usually takes 8-48 hours ACD ACD is not Life threatening The same as immediate hypersensitivity Hives Anaphylactoid symptoms IgE mediated Examples: bee sting, food or med allergy 4

5 Most Common Contact Allergens METALS: nickel, gold, cobalt, chromium Neomycin, bacitracin FRAGRANCES: frag mixes I & II, MP PRESERVATIVES: formaldehyde and FRPs, MCI/MI, MDGN Rubber Diagnosis- history Common contactants in daily life Occupation, hobbies, sports, etc. Disease course Seasonal variation Response to treatment Change of products used not really helpful Itch Atopy Dx- Examination Location (s) of dermatitis Acute- vesicular, weeping, red, inflamed Chronic- scaly, lichenified, pink-red, excoriated Rule out other conditions, e.g. psoriasis, CTCL, etc. 5

6 Dx- tests Patch test is only way to make the definitive diagnosis of ACD ICD manly diagnosed by history, exam, and negative patch tests Biopsy not specific, but can rule out other conditions Patch Testing Allergens applied to back on premade tapes with 8mm aluminum wells Leave on for 48 hours First reading at patch removal Final reading 2 days later M-W-F is typical schedule Patch Test Preparation 6

7 Basic Tips Apply patch-tests to clean, dry, hair-free, non-dermatitic skin on the back Always do at least TWO readings, at time of removal and 2-5 days later Give patients as much info about allergen as you can, they can often help you learn about exposure sources NACDG Allergen Prevalence, 2016 Nickel 16% Neomycin 9% Fragrance Mix I 9% Bacitracin 8% Myroxylon 7% Cobalt 6% Quaternium 15 6% Formaldehyde 6% PPDA 5% Fragrance Mix II 5% Likely Allergens Preservatives Fragrances Other toiletry items: lanolin, propylene glycol, cocamidopropyl betaine, etc. 7

8 Source? Facial skin care Cosmetics Hair care Jewelry Ophth. meds But.. Facial skin more sensitive than other areas Hand to face contact (jewelry, nails, etc) Airborne? Photoallergic contact dermatitis? Most likely cause 1) Nickel 2) Lanolin 3) Formaldehyde 4) Methylisothiazolinone 5) Glue 8

9 Most likely cause 1) Nickel 2) Formaldehyde 3) Gold 4) Methyl methacrylate 5) The cat Continuous for months Think: something that s being used to treat the condition or it s the wrong diagnosis In this case: propylene glycol in topical corticosteroids Pediatric ACD Allergen NACDG Miami/Penn Nickel 28.3% 17.5% Cobalt 17.8% 8.8% Neomycin 8.0% 11.3% Frag Mix 5.1% 6.3% Myroxylon 3.9% 11.3% Jacob S; 2013 patch test training workshop Tempe, AZ 9

10 Patch Testing in kids Italian survey- 349 kids (1-15yrs) 70% had 1 or > positive PTs Nickel, metals, fragrance, preservatives 50% of atopics positive Very similar to adult numbers and allergens Other studies very similar Schena et al, Dermatitis 2012 pp Other Pedi PT Pratt-Ottawa: 70% of kids (4-18y) had positive PTs: Ni, Co, Frag, Neo, etc. Netterlid-Sweden: 31% of 61 atopic kids positive: Ni, Co, lanolin, etc. Jacob-review: 41-77% of kids positive Dermatitis 2008;19: Dermatitis 2013;25: Pedi Derm 2008;25:520-7 When to Patch Test a Kid with Eczema? Eczema is not in typical atopic areas Or it started in typical areas and then spread farther Eczema doesn t respond to usual treatments Onset is beyond about 5 years of age It s a slow day and you have nothing better to do 10

11 Patch Testing in Atopics STRONGLY consider patch testing any chronic, difficult to control atopic patient Worsening dermatitis despite usually adequate treatment Metals, fragrances, topical components (e.g. lanolin, neomycin, etc) most likely But. Beware of irritant PT reactions TRUE-Test Compared to Standard PT Methods True-Test Chambers Allergens preapplied to tapes Gel base Only allergens available You apply allergens to chambers- most often aluminum discs on scanpor tape Petrolatum or water base 11

12 True-Test Good EASY No prep time Allergens well standardizedsame quantity on patch every time Chambers Good Many more allergens available Less expensive (if you do at least 5-10/month) Variety of chambers available TRUE Test Good For Not so good Metal allergy (Ni,Co,Au,Cr) Topical Antibio. Steroids Rubber Form-based preservatives Ortho or dental implants Fragrances? New preservatives-mi and IPBC Surfactants- CAPB Acrylates Some industrial and cosmetic allergens TRUE-Test v. Chamber NACDG pedi study: 39% had positive that would have been missed with only TT Belsito- single center comparison: Chamber better at finding allergy to fragrances, rubber; TT better at nickel, neomycin, MCI/MI. AD 2008;144: JAAD 2001;45:

13 TT Guestimate/Opinion TT much better than no PT at all TT good for infrequent tester Negative TT could still be ACD 40% of the time TT not so effective in many occupational settings Neomycin Cross-reacts with aminoglycosides Gentamycin, tobramycin eyedrops Commonly reported as misdiagnosis of cellulitis with $1,000 s cost to treat Stasis, facial dermatitis most common sites Bacitracin Co-reaction with neomycin About 25% are not allergic to neomycin Most derms now use plain petrolatum after minor surgery instead of topical Abs. 13

14 Formaldehyde May cause allergy from preservatives in topical products and/or from permanentpress clothing May cause generalized dermatitis, erythroderma, or nummular dermatitis Formaldehyde textile allergy more common in elderly Worse in hot weather Formaldehyde Textile Resins Dimethylol urea and melamine FR-1930s Cyclic ureas e.g. DMDHEU- 1960s Methylated DMDHEU and others- 1980s Newer resins generally more expensive and less formaldehyde release. Fabrics often treated with FTRs Synthetic/natural fiber blends, especially polyester/cotton Bed sheets Any garment labeled wrinkle resistant, no ironing needed, permanent press, etc. BUT some of these may be treated with non-formaldehyde finishes 14

15 Clinical Patterns of FTR Allergy Patchy, generalized dermatitis, often sparing underwear areas Usually hands, feet, and face are less affected except if formaldehyde preservative allergy is present Worse where clothing is tight- axillae, shoulders, thighs Nummular dermatitis Formaldehyde Preservatives (FRPs) Quaternium-15 Diazolidinyl urea Imidazolidinyl urea DMDM Hydantoin Bromo-nitro-propanediol Formaldehyde Preservatives Used in cosmetics, soaps, lotions, topical meds, etc Also in metalworking fluids and other industrial fluids 15

16 FRP Allergy Often coexists with allergy to textile resins. Complicates clinical picture because therapeutic agents (moisturizers, corticosteroid creams) often contain them Also commonly found in soaps, shampoos, cosmetics Other Formaldehyde Sources Paper and cardboard Smoke (including cigarettes) Processed wood products (plywood) Foam housing and industrial insulation Embalming fluid and tissue fixatives Some paints and adhesives Patch Testing for FTR Allergy Formaldehyde 2% Formaldehyde 1% Urea Form. Resin (10%) Ethyleneurea Melamine FR (5%) Dimethyloldihydroxyethylene urea FR(5%) Dimethylpropylene urea FR (5%) Tetramethylol acetylenediurea FR (5%) 16

17 MCI/MI Mix of Methylchloroisothiazolinone & methylisothiazoinone TRUE-test calls it Cl+Me-Isothiazolinone Preservative After FRPs, one of the more common preservative allergens MCI/MI Found in many topical products, especially rinse-off products like shampoo and soap Some use in moisturizers, cosmetics, pet products Common industrial use in coolants and metal-working fluids Also some paints, wallpapers Methylisothiazolinone Now more problem seen with MI by itself In PT, the mix concentration is TOO LOW So test MI by itself at 2% Epidemic in baby wipes 17

18 Methyldibromoglutaronitrile Often in products in a mix with phenoxyethanol The MDGN is almost always the allergen Parabens Easily the least allergenic of all common preservatives Other Topical Allergens Propylene Glycol- both allergen and irritant, but low concentration maybe OK Lanolin- from sheep oil glands, purity varies, lanolin alcohols are the allergens Both of these more likely a problem if used on inflamed skin, e.g. stasis dermatitis, etc. 18

19 Surfactants Cocamidopropyl betaine- found in many personal cleansing products and household cleaners Amidoamine and dimethylaminopropylamine may be the true allergens Cocamide DEA, AKA coconut diethanolamide Corticosteroid Allergy (USA) Hydrocortisone family- group A- includes prednisone: % of tested patients and 90% of steroid allergic ide family- group B- desonide, TMC, etc. Group C- desoximetasone, clocortolone, dexamethasone ate family group D- Group C Corticoids: Clocortolone & Desoximetasone Cream, ointment, gel Group C corticoid = virtually no allergenicity Vehicles have minimal allergenicity as well 19

20 Low-Mid Potency Clocortolone cream Desonide ointment Tacrolimus ointment Triamcinolone SPRAY Mid-High Potency TCS Halcinonide ointment Clobetasol spray Desoximetasone ointment Fluocinolone ointment Para-phenylenediamine Most often seen in hairdressers (hands) Common cause of job loss in hairdressers May cause severe scalp/neck dermatitis Henna tattoos- may be adulterated with high levels of PPDA with resulting severe dermatitis at site 20

21 Rubber Allergens Carba Mix, Thiuram Mix, MBT, MBT Mix, Black Rubber (later) Thiourea Mix Carba/Thiuram usually positive together Carbamate: irritant at 48hrs. Rubber Gloves: even nitrile often have Carba, Thiuram, etc. Vinyl does not. Makeup sponges: facial dermatitis Finger dermatitis: rubber bands Do not confuse with Latex allergy (Type IV vs. Type I) Both may coexist. Fragrance Allergy Allergens: Fragrance Mix I & II, Balsam of Peru (Myroxylon Pereriae) Many Others: Jasmine, Ylang-Ylang, etc. Systemic Allergy Botanicals and Herbal Extracts, e.g., Tea Tree Oil, Chamomile, Lavender, etc., etc. 21

22 Fragrance Allergy Points Many herbal and botanical components cross-react with fragrance allergens Some products listed as unscented contain masking fragrances ROAT or Use test by patient often necessary Adhesives & Resins Epoxies- sporting goods, vehicle parts, construction adesives Acrylates- artificial fingernails, bone cement, Krazy glue, many industrial processes Formaldehyde resins- nail polish, glue for shoes and fabrics General References Rietschel RL, Fowler JF: Fisher s Contact Dermatitis, 6 th ed. 2008; BC Decker, Toronto, Ca. Marks JG, DeLeo VA, Elsner P: Contact and Occupational Dermatology 3 rd ed., 2002 Mosby-Year Book, St. Louis, Mo. 22