Management of Occupational Facial Contact Dermatitis in Flower‑Shop Workers

Diagnosis

• The presentation of an erythematous maculopapular rash on the cheek area with pruritus and a burning sensation when wet is characteristic of contact dermatitis in the context of plant exposure. 1
• Occupational exposure to plants provides frequent contact with allergens and irritants that can trigger dermatitis. 1
• Antihistamines such as cetirizine are generally ineffective for contact dermatitis because the condition is mediated by cell‑mediated hypersensitivity rather than IgE. Minimal response to cetirizine therefore supports the diagnosis. 1
• The British Association of Dermatologists (BAD) guidelines state that clinical features alone are unreliable for distinguishing allergic from irritant or endogenous facial dermatitis; definitive testing is required. 2, 3

Immediate Management

Topical Therapy

• Initiate moderate‑to‑potent topical corticosteroids as first‑line therapy for facial rash, selecting a potency that balances anti‑inflammatory effect with the risk of skin atrophy. 2

Medication Review

• Discontinue cetirizine, as it offers no therapeutic benefit for contact dermatitis. 1

Allergen‑Avoidance Measures

• Advise the worker to use protective gloves, face shields, or other barriers when handling flowers to minimize direct skin contact. 1
• Recommend avoidance of wet work and frequent hand‑to‑face contact, which exacerbate irritation. 3
• Review and, if necessary, replace cosmetics, personal‑care products, and topical medications that contact the face. 3

Diagnostic Workup

Patch Testing (Gold Standard)

• Patch testing is the definitive diagnostic investigation for chronic or persistent dermatitis and for facial dermatitis where clinical assessment cannot differentiate etiology. 2
• The test panel should include:

Timing Considerations

• If the worker is receiving systemic immunosuppressants, postpone patch testing for at least 3 months after discontinuation. 2, 1
• If on biologic therapy, defer testing for at least 6 months after stopping the agent. 2
• Antihistamines do not need to be discontinued before patch testing. 3, 1

Occupational History

• Document the pattern of rash improvement on days off (e.g., weekends/holidays) versus worsening on workdays. 3
• Record current personal protective equipment usage. 1
• Capture details of hand‑washing products and hygiene practices. 3

Classification of Contact Dermatitis Types

• Allergic contact dermatitis – cell‑mediated hypersensitivity to specific plant allergens, most likely given the occupational exposure and facial distribution. 1, 3
• Chronic cumulative irritant contact dermatitis – resulting from repetitive exposure to plant saps, water, or chemicals. 1
• Photo‑allergic or photo‑aggravated contact dermatitis – some plant allergens become immunogenic after UV exposure. 1

Alternative Treatments (If Topical Steroids Fail)

• Consider topical tacrolimus as a second‑line agent for steroid‑refractory disease. 2
• For severe, chronic cases, systemic therapies may be contemplated, although they are typically reserved for extensive hand eczema. 2

Critical Pitfalls to Avoid

• Do not rely solely on clinical appearance to differentiate allergic from irritant dermatitis; patch testing is essential. 2, 3
• Do not continue cetirizine expecting therapeutic benefit; it has no role in contact dermatitis management. 1
• Do not delay patch testing; early identification and avoidance of the offending allergen improve prognosis, especially for allergic contact dermatitis. 1
• Do not overlook potential photo‑allergic components; inquire about sun‑exposure patterns given the worker’s outdoor environment. 1

Follow‑Up Plan

• Provide the worker with education materials on the patch‑testing process, possible side effects, and the importance of strict allergen avoidance. 2
• Re‑evaluate the response to topical corticosteroids within 2–4 weeks. 2
• After patch‑test results are available, communicate specific allergen sensitivities, reinforce avoidance strategies, and schedule follow‑up to ensure adherence. 3
• If identified allergens cannot be avoided in the current role, discuss workplace modifications or possible job reassignment. 2

Patch Testing in Mask‑Related Dermatitis

Indications and Diagnostic Value

• Patch testing is the gold‑standard investigation for any patient with chronic or persistent mask‑related facial dermatitis, because clinical features alone cannot reliably differentiate allergic contact dermatitis from irritant or endogenous dermatitis. 4

Timing Considerations for Patch Testing

• Patch testing should be deferred for ≥ 6 weeks after natural or artificial ultraviolet exposure to avoid false‑negative results. 4
• When the patient is receiving systemic immunosuppressants, testing must be postponed for ≥ 3 months after discontinuation of those agents. 4
• If the patient is on biologic therapy, patch testing should be delayed for ≥ 6 months after the biologic is stopped. 4
• Antihistamines do not need to be discontinued before performing patch testing, as they do not interfere with the test outcome. 4

Clinical Pitfalls

• Relying solely on the visual appearance of the rash is insufficient; definitive diagnosis requires patch testing to distinguish allergic from irritant dermatitis. 4

Patient Education and Follow‑Up

• After patch‑test results are obtained, clinicians should clearly communicate identified allergen sensitivities, reinforce strict avoidance strategies, and arrange follow‑up visits to ensure adherence and improve prognosis. 4