Bullous Sweet’s syndrome in a patient with ulcerative colitis: a rare case report Melania Giannoni 1 , Giulio Rizzetto 1 , Claudia Sapigni 1 , Matteo Paolinelli 1 , Corrado Tagliati 1 , Federico Diotallevi 1 ✉ , Anna Campanati 1 , Alessandra Mandolesi 2 , Laura Pepi 2 , Annamaria Ofdani 1 1 Department of Clinical and Molecular Sciences, Dermatology Clinic, Polytechnic Marche University, Ancona, Italy. 2 Department of Experimental and Clinical Medicine, Anatomopathological Institute, Polytechnic Marche University, Ancona, Italy. 153 Introduction Sweet's syndrome (also known as acute febrile neutrophilic der- matosis) is a rare dermatosis characterized by a combination of physical features, clinical symptoms, and pathological speci- mens, including tender erythematous skin lesions (papules, nod- ules, and plaques) located on the arms, upper body, head and neck; high-grade fever; neutrophilia; and an extensive infltration of predominantly mature neutrophils that are typically located in the upper dermis (1). Based on pathophysiology, three subgroups are identifed: idi- opathic, malignancy-associated, and drug-induced (1). Bullous Sweet’s syndrome is a rare clinical variant ofen as- sociated with various kinds of tumors (hematological and solid tumors, including breast, ovarian, testicular, prostatic, rectal, and colon adenocarcinoma), infections, and active infamma- tory bowel diseases (IBDs; Crohn’s disease and ulcerative colitis) (2–4). Case report We report the case of a 62-year-old female with active ulcerative colitis that visited our dermatologic unit in September 2019 for a sudden onset of fever, gastrointestinal symptoms, and painful skin lesions 10 days afer the interruption of oral corticosteroids for unreported reasons. On physical examination, infltrating purple-erythematous skin plaques, which were partly vesicular, were evident on her lower and upper limbs (Fig. 1a, 1b). The oral mucosa was involved contemporarily with ulcerative stomatitis (Fig. 2). Both erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were elevat- ed (60 mm/h and 15 mg/l, respectively), as well as the neutrophil blood count (10,000 mm 3 ). The patient did not report recent intake of new drugs or infec- tions in the previous few weeks. Blood, urine and fecal cultures, throat swab for Streptococcus pyogenes, and viral serology for herpesvirus 1 and 2, cytomegalovirus, and Epstein–Barr virus were negative for recent infections. Histologic examination of bi- opsy specimens obtained from perilesional skin of the lower limbs showed marked edema of papillary dermis associated with subep- idermal vesiculation (Fig. 3). Marked infammatory infltrate, pre- dominantly neutrophilic granulocytes, is found in the papillary and reticular dermis, mainly perivascular and around the ducts of sweat glands (Fig. 3). Intraepidermal neutrophilic exocytosis was minimally present. Direct immunofuorescence of frozen perile- sional tissue did not demonstrate IgA, IgG, IgM, C3, or fbrinogen deposits. Based on clinical and histological features, the diagnosis of Sweet’s syndrome was made. We treated our patient with intravenous daily administration of betamethasone sodium phosphate, starting from 5.5 mg, followed by gradual dose tapering for 12 weeks consecutively. Systemic ad- ministration of high-potency corticosteroids resulted in rapid dis- appearance of both fever and gastrointestinal symptoms within 2 days, followed by gradual clinical resolution of skin eruption and great improvement of oral involvement. Currently, 4 months afer acute illness, both Sweet’s syndrome and ulcerative colitis are in complete clinical remission (Fig. 4), as confrmed by post-therapy colonoscopy (MAYO 0-1). The patient is still continuing chronic anti-infammatory treatment with oral mesalazine at 2.4 g once a day. 2020;29:153-155 doi: 10.15570/actaapa.2020.31 Abstract Bullous Sweet’s syndrome is an uncommon clinical presentation of classical Sweet’s syndrome, ofen associated with various kinds of tumors, infections, and active inflammatory bowel diseases (IBDs), namely Crohn’s disease and ulcerative colitis. Only a few cases of bullous Sweet’s syndrome associated with ulcerative colitis are described in the literature. We report a case of a 62-year-old female patient with acute exacerbation of ulcerative colitis associated with infltrating purple-erythematous skin plaques, which were partly vesicular, and oral ulcerative stomatitis. Biopsy was consistent with bullous Sweet’s syndrome. Treat- ment with betamethasone sodium phosphate, starting at 5.5 mg, followed by gradual dose tapering for 12 weeks, resulted in im- provement of the ulcerative colitis and disappearance of the cutaneous lesions. Bullous Sweet’s syndrome most commonly occurs in the setting of hematologic malignancies, suggesting that physicians should perform long-term screening for early diagnosis of hematological and solid malignancies. Keywords: Bullous Sweet’s syndrome, Crohn’s disease, ulcerative colitis Acta Dermatovenerologica Alpina, Pannonica et Adriatica Acta Dermatovenerol APA Received: 15 March 2020 | Returned for modifcation: 16 April 2020 | Accepted: 20 April 2020 ✉ Corresponding author: federico.diotallevi@hotmail.it