mark h. lowitt, md clinical associate professor of dermatology

Mark H. Lowitt, MD

Clinical Associate Professor of DermatologyUniversity of Maryland School of Medicine

Private Practice, Greater Baltimore Medical Center

Contact Dermatitis

CasesClinical Features of Allergic Contact DermatitisMechanisms of Allergic Contact DermatitisPatch Testing

Case 151 y/o FPhlebotomistItchy and painful fingers

and hands, worsening over years

Not seasonal

What’s the diagnosis?What’s the cause?

Case 2Same photo 73 y/o F

Severe eyelid pain and itch worsening over weeks

What’s the diagnosis?What’s the cause?

Case 340 y/o M

Auto mechanic for 20 years

Similar eruption on feet

What’s the diagnosis?What’s the cause?

ErythemaEdemaVesiculationScalingLichenificationWell defined edges

and Straight linesPruritusHistory: The more you treat, the worse it gets

What’s new in contact dermatitis?What makes a good contact allergen?

Low molecular weightLipophilicAble to form covalent bonds with nucleophilic residues on

amino acid side chainsSensitizing potential may be related to chemical reactivity

toward a few specific amino acids involve in sensitization Esp. cysteine residues

North American Tray

Metals: Nickel, Gold, Cobalt, CopperFragrances: Fragrance mix, Balsam of Peru,

Isoeugenol, LyralPreservatives: Quaternium-15, Paraben mix,

Formaldehyde, Kathon CG, Propylene glycol, Thimerosol

Medications: Neomycin, Bacitracin,Tixocortol-21-pivalate, Budesonide

Dyes: P-phenylenediamine, Disperse blueRubber products: Mercaptobenzathiazole, Carba mix,

thiuram mix, mixed dialkyl thioureaOther: Benzocaine, Colophony, ethyl acrylate

Hand DermatitisAllergic Contact DermatitisIrritant Contact DermatitisDyshidrotic EczemaPalmar psoriasisTinea ManumMycosis fungoides

Hand DermatitisPatch test positive for Quaternium-15

Common preservative

Chronic Hand DermatitisMajor Occupational Health Problem40% of all Occupational Health Claims are from skin90% of these are Dermatitis

65% are Irritant Contact 35% are Allergic Contact

THEREFORE, 12% OF ALL WORKMAN’S COMP CLAIMS ARE DUE TO ALLERGIC CONTACT DERMATITIS

Allergic Contact Dermatitis of the Hands22,035 patients patch tested between 1994 and 20046953 had hand involvement959 with a solitary dx of ACD

Quaternium-15 17%Formaldehyde 13%Nickel 12%Fragrance Mix11%Thiuram Mix 10%

Eyelid DermatitisDifferential Diagnosis

Contact dermatitisAtopic dermatitisDermatomyositis

Atopic dermatitis

Dermatomyositis (heliotrope rash)

Patch testing:Positive for Gold sodiumthiosulfate

May be 10% of positive patch testsMore common in women8% of gold + pts have eyelid dermatitisClinical picture can be confusing due to presence of nickel

in gold alloys

Eyelid DermatitisMost common causes of eyelid allergic contact dermatitis:

Gold 22%Fragrance mix 19%Balsam of Peru 17%Nickel 16%Neomycin 9%

Treatment with topical cortisones initially help, but then the condition worsens

Tinea manum (dermatophyte infection)

Patch test positive for BudesonideCross reacts with triamcinolone, fluocinonide, fluocinolone,

desonide, budesonideCorticosteroids were the American Contact Dermatitis

Society 2005 “Allergen of the Year”

Corticosteroid allergyClass A Hydrocortisone and tixocortol type

Cortisone, hydrocortisone, methylprednisolone, prednisoloneClass B Triamcinolone acetate type

Triamcinolone, halcinonide, flucinonide, fluocinolone, desonde, budesonide, amcinonide

Class C Bethamethasone typeBetamethasone, dexamethasone, flucortolone

Class D Hydrocortisone-17-butyrate and clobetasol 17-butyrate

Patient education – CARD Database

Allergic Contact Dermatitis: ReviewHave a high index of suspicion for ACD

Angulated lesions with straight edges and unusual shapeA refractory dermatitis

However, keep your mind open: not all dermatitis is allergic

Allergic Contact Dermatitis: ReviewPatch testing can help to identify the allergenHand dermatitis most often caused by quaternium-15Eyelid dermatitis most often caused by goldIn pts not getting better, consider contact dermatitis to

topical steroids

www.contactderm.org American Contact Dermatitis Society (ACDS)

www.dormer.com Dormer Labs (Canada)

patch test materials

www.allergEAZE.com patch test materials