Contact Dermatitis • Contact Points SYSTEMIC CONTACT DERMATITIS CAUSED BY RECTAL ENEMAS • BORGES ET AL. Systemic allergic dermatitis caused by sodium metabisulfte in rectal enemas Ana S. Borges 1 , Margarida M. Valejo Coelho 1 , Cândida Fernandes 1 , Ana Brasileiro 1 and Margarida Gonçalo 2 1 Dermatology and Venereology Department, Hospital Santo António dos Capuchos, Centro Hospitalar de Lisboa Central, 1169-050 Lisbon, Portugal and 2 Clinic of Dermatology, University Hospital and Faculty of Medicine, University of Coimbra, 3000-075 Coimbra, Portugal doi:10.1111/cod.12971 Key words: case report; rectal enemas; sodium metabisulfte; systemic allergic dermatitis. Sulftes are widely used as preservatives and antioxidants in food and beverages, but also in cosmetic and phar- maceutical products (1) and medical devices (2). Aller- gic contact dermatitis caused by sodium metabisulfte has been increasingly recognized in recent years, and positive patch test reactions seem to be relevant in most patients if carefully investigated (3, 4). Furthermore, systemic aller- gic reactions to sulftes have also been described following oral and/or parenteral exposure (5 – 7). Case Report A 58-year-old man suffering from ulcerative colitis treated with oral mesalazine (5-aminosalicylic acid) 3 g for 4 years without signifcant side-effects presented with recurrent pruritic erythematous lesions located bilaterally on the inguinal area for 3 months soon after Salofalk ® and Pentasa ® enemas had been added to the treatment (Fig. 1a,b). Lesions developed initially 2 days after the use of a Salofalk ® enema. Therefore, the patient was switched to a Pentasa ® enema, which, however, provoked a recurrence of the lesions. These diminished only after 3 days of treatment with oral steroids. The patient denied application of topical products to that area and the use of any other systemic drug. He also mentioned previous episodes of a transient rash 2 days after drinking wine. Apart from ulcerative colitis, his medical history included asthma controlled with mon- telukast and bronchodilators, and eosinophilic gastritis with histopathological confrmation 1year previously, for which he was treated with esomeprazole. Correspondence: Ana S. Ribeiro Borges, Dermatology as Venerology Depart- ment Hospital Santo Antonio dos Capuchos, Centro Hospitalar Lisboa Cen- tral, Lisboa, Portugal. Tel: +351 213136300; Fax: +351 213562208; Email: a.sofia.r.borges@gmail.com Conflict of interest: There are no conflicts of interest to be declared. Fig. 1. Symmetrical confuent maculopapular lesionslocalized in the inguinal area and upper thighs. On examination, the patient had symmetrical con- fuent maculopapular lesions with ill-defned borders, with some lesions resembling erythema multiforme, localized in the inguinal area and on the upper thighs. There was no involvement of the buttocks or perianal area. Contact dermatitis was suspected, and patch testing was performed with the Portuguese baseline series, the patient’s own enemas, that is, Salofalk ® ‘as is’ (contain- ing mesalazine, sodium benzoate, disodium EDTA, sodium metabisulfte, potassium acetate, and xanthan gum) and Pentasa ® ‘as is’ (containing mesalazine, disodium EDTA, sodium metabisulfte, sodium acetate, and hydrochloric acid), and relevant excipients. Readings on day (D) 3 and D7 showed positive reactions to Salofalk ® (++, ++), Pentasa ® (++, ++), and sodium metabisulfte 1% pet. (Chemotechnique, Vellinge, Sweden; ++, ++). Patch tests with Salofalk ® and Pentasa ® enemas ‘as is’ in 10 healthy volunteers gave negative results. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd Contact Dermatitis, 78, 413–430 429