Tehran University of Medical Sciences Case Reports in Clinical Practice 2538-2683 2 4 2018 05 14 103 106 EN Safoura Shakoei Department of Dermatology, School of Medicine AND Imam Khomeini Hospital, Tehran University of Medical Sciences, Tehran, Iran. Maryam Ranjbar Department of Dermatology, School of Medicine AND Imam Khomeini Hospital, Tehran University of Medical Sciences, Tehran, Iran. Masoumeh Rohani Nasab Department of Dermatology, School of Medicine AND Rasoul Akram Hospital, Iran University of Medical Sciences, Tehran, Iran. Azita Nikoo Department of Pathology, School of Medicine AND Razi Hospital, Tehran University of Medical Sciences, Tehran, Iran. 2017 11 07 2018 01 10 Wells syndrome is an uncommon disease that typically presents as edematous erythematous plaques, usually preceded by burning or itching of the skin. Histopathological examination shows dense dermal eosinophilic infiltrates in an edematous dermis at the acute phase of lesions. Some of the identified triggering factors include infection, arthropod bites, hematological malignancies, thimerosal containing vaccines and drugs such as penicillin, lincomycin, tetracycline, minocycline and ampicillin. Here we describe a case of Wells syndrome in a 75-year-old woman that its outstanding feature was its large size. Although this case was resistant to our treatment, the condition improved spontaneously after several weeks without administering any other alternative treatments. On the other hand, despite its large size, this case had no identifiable trigger. https://crcp.tums.ac.ir/index.php/crcp/article/view/149 https://crcp.tums.ac.ir/index.php/crcp/article/download/149/91