ACD Flashcards
Definition
Eczematous reaction that occurs as an immunological response
Following exposure to a substance
To which the immune system had oreviously been sensitised
Young adults
- Occupational allergy
- Cosmetic allergy
Elderly
- Medicament allergy
- ‘Historic’ sensitivity acquired over lifetime
Most prevalent contact allergens
Nickel
- Suspenders
- Earrings
- Watches
- Jean studs
Thimerosal
Fragrance mix
- Cosmetics
Cobalt
Chromium
- Wet cement
PPD (p-phenylenediamine)
- black hair dye
MCI/MI (methylchloroisothiazolinone/methylisothiazolinone)
Most prevalent contact allergens in children
Nickel (ear piercings, jewellery) —> esp in girls
Fragrance
Thimerosal (? Vaccines, inoculations) —> may not be relevant
Medicaments
Rubber chemicals (from footwear)
Chromate (from footwear)
Resins (from footwear)
PPD (from contaminated Henna tattoo)
Subgroups with impaired capacity for contact sensitisation
Cancer
Hodgkin disease
MF
Other conditions with T lymphocyte function impairment
Drugs that reduce intensity of APT reactions
Potent TCS
Oral prednisolone > 15mg/day
CSA (immunomodulator)
AZA (immunomodulator)
NbUVB (local immunosuppressant)
PUVA (local immunosuppressant)
DRUGS WITH LITTLE EFFECT
Antihistamines
Sodium cromoglycate
Predisposing factors
Pre-existing/concomitant endogenous dermatitis +/- irritant contact dermatis
- damages skin
- impaired barrier function
- increased opportunities for allergen absorption, secondary sensitisation
- longer duration of eczema —> greater chance of sensitisation
Occlusion and increased sweating
- promotes percutaneous absorption
- contributes to medicament dermatitis in stasis eczema, perianal dermatitis, otitis externa (ear drops)
- dermatitis from shoes
- dermatitis from rubber gloves
- dermatitis from clothing
Concomitant ICD
- Sensitivity more easily acquired if allergen applied on damaged skin
- Damaged skin lowers Threshold for elicitation of ACD
- tolerance of the allergen if no concomitant irritancy
Duration of exposure
- rinse off vs leave on products
Repeated exposure
UV absorbing chemical filters in sunscreens
- blocks out the UVB that diminishes the skin’s immune response to contact allergens in the setting of the chemical exposure
Plants
- facilitated by dry and windy climates
- Compositae (Asteraceae) family in spring/summer
Cheap jewellery
- contains nickel
Cultural factors
- Traditional herbal medicines and balms on the skin
- Kumkum and bindi usage in Indian women —> contact with dye, adhesives
- Hair dyes —> contact with PPD
- Tattoing —> contact with nickel, PPD
No definite conclusion whether atopic dermatitis predisposes to ACD
History
PRIMARY SITE/SITE OF ORIGIN
Contact dermatitis must begin in sites where contact has taken place with the allergen
DURATION AND BEHAVIOUR
Did the condition spread —> where?
Is the problem persistent or intermittent (repeated sudden exacerbations points to ACD in line with the exposures)
Exacerbating factors
- seasonal variation i.e. worsening when light intensity greatest (suggests plant allergen d/t photoaggravation or photoallergy —> atypical patterns)
- medicaments i.e. dermatitis around a wound esp leg ulcers
- cosmetics
Any improvement during weekends or holidays (indicates occupational origin)
Any relapse at weekends (favour hobby or non-occupational origin)
PREVIOUS HX
Previous dermatitis may be a clue to origin of a relapse
- earring dermatitis preceding nickel dermatitis of the hands by years
- previous dermatitis to the lower legs caused/complicated by repeated topicals comtaining sensitisers
Skin reactions to costume jewellery (nickel)
Skin reactions to perfume (frangrance)
Skin reactions to adhesive plasters (colophony, resins)
Atopic diathesis
- Infantile/childhood flexural eczema
- Asthma
- Seasonal hayfever
Atopic eczema (risk for ICD)
SOURCES OF ALLERGY Present and past occupation —> see below Hobbies Cosmetics Clothing Personal objects —> see below Home environment Current and previous prescribed and OTC topical medicaments - those used for a long time commonly responsible
OCCUPATIONAL HX
Ask about casual work or second jobs
Presence of other similar cases at work (red flag to increased probability of occupational dermatitis)
Usage of supplied topicals at work
- Cleansers
- Barrier creams
- Conditioners
Examine health and safety data sheets
- chemical names of materials
- indication of irritancy/allergenicity
- telephone nimber/email for further enquiries
Site visit to become familiar with the process described
HOBBIES “Hobby dermatitis” Industrial allergens (well known sensitizers) for home DIY - cement - glues - paint - wood - wood preservatives
Gardening
Cooking
Car maintenance
Sport
PERSONAL OBJECTS AND MEDICINES —> worn or applied to skin Textiles Footwear Protective clothing Gloves Jewellery Spectacles Hearing aids Medical appliances Cosmetics Toiletries - cosmetic removers i.e. creams, lotions, wipes - skin cleansers (rinse-off) - hair products (rinse-off and leave-on) Fragrances Medicaments (prescribed and OTC) - moisturisers - Herbal treatments - Borrowed medicaments Nail varnish Artificial nails Hair dyes
Clinical presentation
ACUTE ACD —> reflects sequence of inflammatory changes in the dermis and intracellular, intercellular oedema in the epidermis
Erythema
Swelling
Papules —> Papulovesicles —> bullae —> weeping dermatitis if rupture
Itch
CHRONIC ACD —> may be d/t continued /repeated exposure to the allergen or to secondary irritants/allergens
Dry Scaly (hyperkeratosis) Thick (acanthosis, oedema) Lichenification Fissuring
BULLOUS ERUPTION
Strong allergen
LINEAR PATTERN
Phytophotodermatitis
Plant dermatitis
Hands and Forearms
Multifactorial
- ICD
- ACD
Allergens may be traced by relating the shape and site of eczematous patches to the items handled
Rubber gloves
- dermatitis over sites they are worn esp involving dorsa of the hands with a sharp line of demarcation at the wrists
Immediate hypersensitivity to animal and plant proteins
- Agriculture workers
- Animal handlers
- Food prep handlers
VESICULAR PALMAR CONTACT DERMATITIS (mimics constitutional pompholyx)
Chromate in cement
N-isopropyl-N-phenyl-p-phenyldiamine
1,2-benzisothiazolin-3-one
DISCOID PATTERN
Chromate in cement
STREAKY DERMATITIS FINGERS, DORSA HANDS, FOREARMS
Plants
- Allergic (Primula obconica, poison ivy)
- Irritant (Dieffenbachia, spurge)
- Phototoxic (giant hogweed, rue)
FINGERTIPS
Plant
- tulipalins (horticulturalist, florists) —> “tulip fingers”
Garlic
- chefs
- non-dominat thumb, forefinger, middle finger
FOREARMS
—> Affected by the same allergens as the hands but usually later
—> May be major sites of occupational dermatitis if hands have been protected at work
Watchstraps
- Nickel (metal)
- Chromate (leather)
- P-tertiary-butylphenol formaldehyde resin (glue)
ELBOW FLEXURES
Dust
- exotic woods
- cement
Nickel
Textiles
Face
Occur alone or in assoc with eczema elsewhere
COSMETICS
Fragrances
Preservatives
—> Starts with dryness, tightness, itch
HAIR DYES
May provoke acute oedema + intense itch, no eczema —> desquamation
NAIL VARNISH/NAIL STRENGHENERS/NAIL HARDENERS/ACRYLIC-BASED ARTIFICIAL NAILS
Well demarcated and localised patches
May be assoc with eyelid dermatitis + more extensive involvement neck, chest, beyond
RUBBER SPONGE MAKE-UP APPLICATORS
Well demarcated and localised patches
May be assoc with eyelid dermatitis + more extensive involvement neck, chest, beyond
HAIR PRODUCTS APPLIED TO HAIR
Affects forehead
CHROMATE IN LEATHER HATBANDS
Affects forehead
SPECTACLE FRAMES
Nickel
Plastics
—> dermatitis on aeas of contact with cheeks, nose, eyelids, ears
AIRBORNE / VOLATILE ALLERGENS Involves - eyelids - skin below the chin - behind and below ear lobes
PHOTOSENSITISING DRUG
Triangles of relatively spared skin below the chin
Sparing of behind and below ear lobes
Eyelids
Allergens affecting the face may initially produce eyelid dermatitis —> Skin of eyelid thin, sensitive
NAIL VARNISH
Skin of eyelid may be contaminated by fingers
COSMETICS —> eye creams, eye shadow, mascara, eye make-up removers
May be ICD and/or ACD
EYELASH CURLER
Nickel
Rubber
MAKE-UP APPLICATORS
Nickel
Rubber
FRAGRANCE SPRAY (airborne droplets)
EPOXY RESIN (volatile substance)
EYE DROPS & EYE MEDICAMENTS ABs - Neomycin - Framycetin - Gentamicin - Tobramycin - Chloramphenicol - Fucidin - Sulphonamides
LA
Antihistamines
B-blockers
Anti-cholinergics
Sympathomimetics
EYE DROPS & CONTACT LENS SOLUTION Preservatives - Benzalkonium chloride - EDTA (ethylenediamine tetracetate) - Mercurials
Lips, perioral
LIPSTICKS & SALVES
May be limited to the vermillion border —> dry, scaling, cracked
+/- perioral area
LIP COSMETICS WITH SPF
Sunscreen agents
—> photoallergic contact cheilitis
COSMETIC EXCIPIENTS
MEDICAMENTS
NICKEL-PLATED OBJECTS Keys Pins Musical instruments —> sensitisers habitually carried to the mouth
NAIL VARNISH
SHELLAC
TOOTHPASTE Flavours (fragrances) - Cinnamic aldehyde - Spearmint oil - Peppermint oil - Anethole - l-carvone —> Cheilitis, Perioral eczema
CHEWING GUM
Colophonium and derivatives
FOOD ADDITIVES Sodium metabisulphite Preservatives Colours Antioxidants
GARLIC
Ears
SECONDARY MEDICAMENT CONTACT DERMATITIS
Habitual scratching with hairpins (nickel)
Habitual scratching with fingertips (nail varnish)
DERMATITIS FROM HEARING AIDS (often a non-specific consequence of occlusion)
Acrylates
Plasticizing chemicals
Stabilising chemicals
DERMATITIS FROM HEADSETS
Urea
Phenol-formaldehyde resins (in the earphones)
Rubber (in the earphones)
SPECTACLE FRAME DERMATITIS (may be of irritant origin, esp behind and over the ears)
Metals
- Nickel
- Palladium
Plastic components
- Epoxy resins
- Acrylates
- Plasticizers
- UV inhibitors
- Dyes
DERMATITIS FROM EARPLUGS Antiseptics Dyes Rubber Plastic chemicals Formaldehyde resin finish
DERMATITIS FROM SHOWER CAPS/HAIR DYE CAPS (retro-auricular area)
Elastic
DERMATITIS FROM EARRINGS/CLIPS (ear lobe)
Nickel
Gold (less common)
Palladium
Scalp
Tends to be relatively spared from ACD
HAIR COSMETICS (shampoo, conditioner)
Fragrances
Preservatives
Amphoteric detergents
—> Dermatitis usually limited to ears, face, neck; may be preceded by persistent itching of the scalp
HAIR STYLING PRODUCTS (mousses, gels, waxes, holding spray)
Fragrances (allergenic)
Preservative (allergenic)
Conditioning quarternary ammonium compound (often irritant)
MEDICATED SHAMPOOS
Tar extracts
Zinc pyrithione
GENERAL SHAMPOOS Preservatives - Formaldehyde - Formaldehyde releasers - Isothiazolinones
Cocamidopropylbetaine
HAIR DYE
PPD
HAIR BLEACHING AGENT
Ammonium presulphate —> cause peculiar urticarial eruptions, ACD
HAIR PERMS
Glyceryl monothioglycollate —> significant sensitiser in hairdressers, occaisonally causes problems in clients
TOPICAL MEDICAMENT
Minoxidil lotion
Neck
NICKEL (small area of dermatitis on the nape of the neck)
- Clasps of necklaces
- Zip fasteners
NAIL VARNISH (patchy dermatitis sometimes simulating LSC) - transfer from fingertips
TEXTILES (collar-like dermatitis, dermatitis on sides of neck)
- finishes in collars
- dyes
NECKLACES (collar-like dermatitis, dermatitis on sides of neck)
Nickel
Exotic wood
AIRBORNE ALLERGENS & PHOTOSENSITIZERS (sharply limited by the collar to the V of the neck)
PERFUME (ACD + phototoxic/Berloque dermatitis esp sides of neck)
