Diagnosis and Management of Recurring Round Dermatitis Patch

Introduction to Diagnoses

• The American Academy of Dermatology suggests that a recurring round dermatitis patch that responded temporarily to hydrocortisone but returned after stopping treatment is most consistent with either nummular (discoid) eczema or allergic contact dermatitis, and recommends seeing a dermatologist for patch testing to identify potential allergens and consider stronger topical corticosteroids or alternative treatments for long-term control 1, 2, 3

Clinical Features and Diagnoses

• Allergic Contact Dermatitis (ACD) manifests as eczematous lesions that are often clinically indistinguishable from other forms of dermatitis and can present as localized round patches 1, 2
• The recurrence pattern suggests ongoing exposure to an allergen that is contacted repeatedly in that specific location 1, 2, 3
• Common allergens include nickel, fragrances, preservatives in lotions/creams, rubber chemicals, and even ingredients in topical medications 1, 2
• A small subset of patients can even develop allergic contact dermatitis to topical corticosteroids themselves, which could explain why it improved initially but returned 1, 2

Management and Treatment

• The American Academy of Dermatology recommends referral to dermatology for suspected allergic contact dermatitis requiring patch testing 4
• Patch testing involves placing suspected allergens on unaffected skin (typically the back) for 48 hours, with readings at removal and again at days 4-7 1, 2
• The sensitivity of patch testing ranges from 60-80%, and positive results must be correlated with clinical history 1, 2
• Apply fragrance-free moisturizers with petrolatum or mineral oil immediately after bathing to damp skin, as these are most effective and least allergenic 5
• Use lukewarm or cool water for washing rather than hot water, which damages the skin barrier 4, 5
• Pat dry gently rather than rubbing the affected area 4, 5
• Avoid harsh soaps, detergents, and fragrances on or near the affected area 5

Avoiding Pitfalls

• Don't apply known irritants like dish detergent or harsh soaps to the area 4
• Avoid using very hot water for washing 4, 5
• Don't use superglue to seal any cracks or fissures that may develop 4

Treatment of Recalcitrant Cases

• Consider stronger topical steroids, phototherapy, or systemic therapy options for recalcitrant cases 4
• The British Association of Dermatologists recommends considering topical tacrolimus when topical steroids are unsuitable or ineffective 3
• For severe chronic cases, alitretinoin or PUVA therapy may be considered 3, 4