Extensive allergic contact dermatitis to dexpanthenol with distant facial and symmetrical intertriginous involvement: An unusual clinical presentation

Dexpanthenol, a derivative of panthothenic acid, is a common agent in wound-healing ointments, cosmetics and moisturising lotions due to its anti-inflammatory and regenerative properties.1 Its potential to cause allergic contact reactions is rare and is therefore often overlooked.1 A 38-year-old male technician presented with pruritic erythematous confluent papules and plaques on the ventral left forearm, left cubital fossa and left ventral abdomen with symmetrical exanthematous involvement of the intertriginous folds (Figure 1A–D). Periorbital oedema and oozing erythematous plaques with honey-yellow crusts were observed on the face and neck (Figure 1E). He had previously applied Bepanthen® Plus Cream (containing dexpanthenol and chlorhexidine dihydrochloride) for 8 days to a newly engraved tattoo on his left lower forearm, where the rash was most severe. Symmetrical drug-related intertriginous and flexural exanthema (SDRIFE) was ruled out by lack of systemic drug use in the temporal context. Biopsy of the left arm revealed a spongiotic dermatitis compatible with disseminated eczema. Suspicion of secondary impetiginisation was confirmed by detection of Staphylococcus aureus in cheek and ear swabs and colonisation of the nose. Intertriginous Candida infection was mycologically excluded. Skin testing with repeated open application of Bepanthen® Plus Cream showed a clearly positive reaction with manifestation of erythematous papules and plaques after 24 h (Figure 2A). Antiseptic treatment with chlorhexidine digluconate and antibiotic- and steroid-containing cream was well tolerated. Skin Patch Testing was carried out according to the German Contact Dermatitis Research Group (DKG) guidelines using Finn Chambers on Scanpor tape. The testallergens were provided by SmartPractice, especially chlorhexidin gluconat 0.5% in aqua and dexpanthenol 5% in petrolatum. Bepanthen® Plus and Bepanthen® Cream (Bayer, Switzerland AG, Zurich) were tested ‘as is’. Readings on day 2 and 3 showed type IV hypersensitivity only to dexpanthenol, confirming allergic contact dermatitis due to exposure to this ointment component (Figure 2B). According to data from the Information Network of Departments of Dermatology (IVDK) in cooperation with the German Contact Allergy Group (DKG), only 1.2% of patients with dexpanthenol patch testing between 1992 and 1999 had a positive reaction.2 Previous case reports in the literature predominantly describe only localised contact allergic reactions with regional spread, most commonly on the hands, face, and lower legs.1-4 In contrast, our case demonstrates the potential of dexpanthenol-containing ointments to also induce extensive allergic contact reactions that can involve distant anatomical sites and even clinically imitate SDRIFE. Thus, caution is warranted when applying hapten containing products to newly tattooed skin, as the tattoo injury may promote sensitization.5 We also encourage the inclusion of dexpanthenol in the standardised patch test series for topical pharmaceuticals and cosmetics. Elisabeth Victoria Goessinger: Writing – original draft; conceptualization; writing – review and editing. Tamara Merkel: Conceptualization; writing – review and editing. Sibylla Chantraine: Supervision; writing – review and editing. Karin Hartmann: Supervision; writing – review and editing; conceptualization. We thank the patient for providing consent to publish this case report. Open access funding provided by Universitat Basel. The authors declare no conflicts of interest.