Allergic contact dermatitis and delayed wound healing from panthenol

Panthenol is frequently present in (hypoallergenic) cosmetics, including moisturisers and wound-healing creams. We report a case of allergic contact dermatitis (ACD), and delayed wound healing, caused by several cosmetic creams containing panthenol. A 26-year-old woman was referred with acute eczema of the face that had lasted for 10 days. She was also suffering from, eczema in the armpits, and on the right thigh, since she had benefited, 2 months earlier, from a skin graft from her thigh to her armpits to treat hidradenitis suppurativa. She experienced eczema of these particular skin locations, and delayed wound healing, since surgery. Clinical Examination revealed intense erythema and vesicles on the face (Figure 1A) and thigh/axillae (Figure 1B). The eczema responded well to treatment with topical corticosteroids, yet had a tendency to recur. At the dermato-allergology visit, she initially reported that no new cosmetics were applied. However, after carefully reviewing her recent medical history, she had apparently been applying, since a few months several creams on her face, that is, SENSIBIAFINE® nourishing and light cream (Johnson & Johnson Santé Beauté, Issy les Moulineaux, France) and DIADERMINE mattifying and protecting cream (DIADERMINE LABORATOIRES, Breda, the Netherlands). Moreover, she had been recommended daily aftercare treatment of the armpits and thigh wounds with CICAPLAST baume B5 and CICAPLAST baume lavant (liquid soap; LA ROCHE-POSAY Laboratoire Dermatologique, La Roche-Posay, France) to speed up the healing process. Patch testing was performed with the European and cosmetic series and patient's cosmetics (Chemotechnique Diagnostics, Vellinge Sweden) and with her own cosmetics. The haptens were applied on the back using IQ Ultra chambers (Chemotechnique Diagnostics), and following an occlusion of 2 days readings were performed on day (D)-2 and D3. Positive reactions were observed to panthenol 5% pet. (cosmetic series) and also to her own cosmetic products SENSIBIAFINE cream, DIADERMINE cream, CICAPLAST baume B5 and CICAPLAST lavant (liquid soap), all containing panthenol (Figure 2). A diagnosis of ACD from panthenol contact allergy, also contributing to delayed wound healing (thigh, axillae) was thus confirmed (Table 1). Avoidance of panthenol-containing products made the eczema disappear and allowed normal wound healing. Panthenol (CAS no. 81-13-0) is an analogue of pantothenic acid (vitamin B5) that is used in pharmaceuticals, (topical) medical devices and cosmetics.1 In the literature divergent opinions exist whether panthenol is a frequent or rather rare sensitizer. In Fernandes' study, over a 15-year period, 1.2% of patients were found to be sensitised to panthenol with a 76.9% relevance grade.2 Yet in another study, only 0.7% reactions were found in 3301 patch tested subjects.3 According to a more recent study, the impurity pantolactone may be the actual sensitizer, particularly in wound-healing creams,4 although this would need further confirmation. In our patient's case the wounds (thigh, axillae), that is, compromised skin, likely facilitated penetration and subsequent skin sensitization, as also suggest by previous reports.2 Panthenol is important to consider as a contact allergen especially in product applied on damaged skin. However, as demonstrated here, also on uncompromised skin (face) it may act as a sensitizer, although this appears to occur less frequently. Interestingly, panthenol contact allergy has, to the best our knowledge, never been previously reported to be contributing to delayed wound healing. Clinicians should be aware of the increasing use of topical products, cosmetics and others, containing panthenol, and its associated risk of allergic contact dermatitis. Indeed, it is apparently often present in (‘hypoallergenic’) cosmetics for sensitive skin.5 The hapten panthenol is currently of interest, and researchers have also suggested to monitor its sensitization.6 For this reason, it is important to report about panthenol contact allergy. The patient's written consent was obtained. Magalie Coco-Viloin: Conceptualization; investigation; writing – original draft; methodology; writing – review and editing. Jeanne Ramspacher: Investigation. Françoise Giordano: Supervision; validation. The authors declare no conflicts of interest.