CONTACT POINT Thiuram allergic contact dermatitis on the hands after skin contact with a rubber cellphone case Dathan Hamann 1,2 | Margrethe Bordado Sköld 3 | Carsten R. Hamann 4,5 | Jacob P. Thyssen 4,5 1 Department of Internal Medicine, Division of Dermatology, The Ohio State University, Columbus, Ohio 2 Contact Dermatitis Institute, Phoenix, Arizona 3 Department of Occupational and Environmental Medicine, Bispebjerg Hospital, University of Copenhagen, Copenhagen, Denmark 4 Department of Dermatology and Allergy, Herlev and Gentofte Hospital, University of Copenhagen, Hellerup, Denmark 5 Copenhagen Research Group for Inflammatory Skin Disease (CORGIS), Hellerup, Denmark Correspondence Dathan Hamann, MD; Contact Dermatitis Institute, 3400 E McDowell Rd, Phoenix, AZ 85008. Email: dathanhamann@gmail.com Funding information Lundbeckfonden KEYWORDS: accelerator allergy, allergic contact dermatitis, case report, contact allergy, occupational, thiuram CASE REPORT A 34-year-old woman with a childhood history of atopic dermatitis pre- sented to our hospital-based clinic in late 2013 with occupational hand eczema. At the time, patch testing was performed with the European baseline test series, with a departmental extension, a corticosteroid test series, a fragrance test series, and a rubber test series (Allergeaze, SmartPractice Europe, Barsbüttel, Germany), as well as with the patient’s own products. Patches were applied on the upper back under occlusion for 2 days in Finn Chambers (8 mm; SmartPractice, Phoenix, Arizona) on Scanpor tape (Norgesplaster, Alpharma, Vennesla, Norway), and read on day (D) 2, D3, and D7, according to ESCD guidelines. 1 Patch testing showed positive reactions to thiuram mix (+) and tetra- methylthiuram monosulfide (+) on D7. The patient’s dermatitis on the hands improved significantly with avoidance of thiuram by switching to a thiuram-free synthetic rubber glove, and with the use of class 3 topical steroids. She was diagnosed with occupational irritant contact and occupational thiuram allergic contact dermatitis (ACD) secondary to daily use of nitrile gloves. The patient re-presented 3 years later with significant worsen- ing of pruritus and hand dermatitis of 12 months’ duration, starting on her left palm. The dermatitis then spread to both dorsal and ventral aspects of the hands and wrists, with prominent vesicles, and corre- sponded to skin areas where dermatitis had been observed in 2013 (Figure 1). The patient’s exposures were reviewed again, and she sus- pected that her worsening could be attributable to a rubber case that she used to protect her iPhone, which she had purchased 18 months before. She had no relevant occupational exposures. The unilateral distribution of the initial contact dermatitis corresponded to her com- mon practice of holding her phone with her left hand. Importantly, her symptoms subsided within 2 weeks of her removing the rubber cell phone case. Unfortunately, she discarded the cell phone case, making chemical analysis impossible. DISCUSSION We present here a case of thiuram contact dermatitis caused by a rub- ber cell phone case occurring in an atopic woman with known occupa- tional allergic rubber dermatitis. Mobile phones and accessories have been identified as sources of daily exposure to metal allergens such as nickel, chromium, and cobalt, and metal ACD caused by mobile phone use has been reported worldwide. 2 Non-metallic causes of mobile phone ACD are limited to 2 cases, neither of which involved rubber allergens. 3,4 To our knowledge, this is the first report of a suspected case of mobile phone-associated ACD caused by a rubber allergen. In patients with occupational ACD with new exacerbations, clinicians should be mindful of consumer exposures. ACKNOWLEDGEMENTS J. P. Thyssen is supported by an unrestricted grant from the Lundbeckfonden. Received: 4 September 2018 Accepted: 6 September 2018 DOI: 10.1111/cod.13140 © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd Contact Dermatitis. 2018;1–2. wileyonlinelibrary.com/journal/cod 1