January 2020 Case Study – Derm In-Review

January 2020 Case Study

The patient is a 40 year old female who presents for evaluation of persistent eyelid dermatitis. The eyelid dermatitis has been present for 1 year and has never completely resolved while using topical corticosteroids or calcineurin inhibitors. She describes the rash as itchy but not painful and has not noticed any lesions in other areas. Currently she uses “all natural” personal and cosmetic products including a “fragrance-free” oil on the face. The patient is diagnosed with allergic contact dermatitis of unspecified trigger and patch testing is performed to the North American Standard Tray and Cosmetic Tray (Image 1). A positive patch reaction is noted on the 96 hour read (Image 2). Which of the following allergen did this patient likely react to?

A.) Dimethylol dihydroxyethylene-urea resin
B.) Lanolin
C.) Paraphenylenediamine
D.)Melaleuca alternifolia
E.) Fragrance mix (cinnamic alcohol, cinnamic aldehyde, hydroxycitronellal, amylcinnamaldehyde, gerianiol, eugenol, isoeugenol, oakmoss)

Correct answer: D. Melaleuca alternifolia

Allergic contact dermatitis (ACD) is an inflammatory skin disorder characterized by delayed type IV hypersensitivity. It has a prevalence of approximately 20% and patients with atopic dermatitis may have an increased risk of developing contact dermatitis.1 The eyelids and periorbital area are common locations for ACD and are frequently due to allergens found in cosmetic and personal products including fragrances, formaldehyde-related preservatives, methylisothiazolinone, and cocamidopropyl betaine.1

Patch testing is the best tool to confirm a diagnosis of ACD.2 It involves applying allergens on a patch to the back or upper outer arm of the patient. The patches are removed after 48 hours where an initial read is taken and then a final read is completed at day 4 or day 5. A positive reaction will reveal an erythematous papule or vesicle with edema.2

Melaleuca alternifolia leaf oil is commonly referred to as tea tree oil and is becoming a frequent cause of ACD. M. alternifolia is a part of the North American Contact Dermatitis Group screening patch tray and has a prevalence of 3.5% of positive reactions.3 Clinically, patients have a localized dermatitis depending on where the product is topically applied. The periorbital area is a common location for cosmetic products.3 Patients may present with erythematous patches to eczematous plaques to bullous or erythema multiforme-like reaction.4 When there is a high suspicion of M. alterifolia as a cause of ACD, patients should be patch tested to the 5% formulation in petrolatum along with the patient’s personal products if possible.4 Allergy avoidance and providing the patient with a list of safe products is a necessary part of treatment.

Other answer choices:

Formaldehyde resins like, dimethylol dihydroxyethylene-urea, are commonly used in fabric production to make them wrinkle or water resistant.5 Lanolin contains sterols or fatty acids and is common in many personal and cosmetic topical lotions and creams.5 Paraphenylenediamine (PPD) is used in hair dye and frequently causes ACD of the scalp, eyelids, ears, forehead, and neck.5 There are 2 fragrance mixes found in the North American Contact Dermatitis Group screening tray which covers many fragrances found in perfumes/colognes, oils, cosmetic, personal and household products.5


  1. Nassau, S., Fonacier, L. F. (2020). Allergic contact dermatitis. Med Clin N Am, 104, 61-76.
  2. James, W., Elston, D., Treat, J., Neuhaus, I., & Andrews, G. (2020). In Edinburgh (Ed.), Andrews’ diseases of the skin : Clinical dermatology (Thirteenth edition ed.) Elsevier.
  3. de Groot, A. C., & Schmidt, E. (2016). Tea tree oil: Contact allergy and chemical composition. Contact Dermatitis, 75(3), 129-143. doi:10.1111/cod.12591 [doi]
  4. Larson, D., & Jacob, S. E. (2012). Tea tree oil. Dermatitis, 23(1) Retrieved from https://journals.lww.com/dermatitis/Fulltext/2012/01000/Tea_Tree_Oil.10.aspx
  5. Allergen information. (2020). Information posted to https://www.contactderm.org/public-and-patients/allergen-information

Author Krista Reznik

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