Clinicopathological Cases

Abstract

CPC01 Do we categorize and investigate patients with Sweet syndrome appropriately? A retrospective review of 64 cases N. Gopee and P. Hampton Royal Victoria Infirmary, Newcastle upon Tyne, U.K. Sweet syndrome (SS) is a neutrophilic dermatosis that can be categorized as malignancy associated (MASS), drug-induced or classical, which can be further classified as idiopathic, triggered by infection or inflammatory conditions. Although some reports have attempted to define recommendations for the management of SS, no definite consensus exists on investigations or follow-up required (Cohen PR. Sweet’s syndrome – a comprehensive review of an acute febrile neutrophilic dermatosis. Orphanet J Rare Dis 2007; 2: 34). This study aims to analyse the management of SS in our department, describing patients’ clinicopathological features, whether cases were categorized according to triggers, and the investigations, treatment and follow-up undertaken. Electronic records of patients diagnosed with SS between January 2005 and December 2018 were retrospectively reviewed. In total, 64 patients were identified (67% female; mean SD age of onset 54 18 years). SS was associated with infection in 17 (27%) patients, inflammatory conditions in 8 (13%), haematological disorder in 11 (17%) and solid organ malignancy in 8 (13%). It was drug induced in 2 cases (3%) and considered idiopathic in 24 (38%). No categorization was suggested for 34 (53%) cases, of which 9 had an identifiable trigger at presentation, 4 were later classed as infection-triggered when they relapsed and 3 were subsequently diagnosed with a malignancy: 2 myelodysplastic syndromes (at 8and 19-months post diagnosis at relapse or follow-up) and 1 colonic tumour (not diagnosed through dermatology). The main investigations undertaken overall included blood counts and inflammatory markers (91%), blood film (28%), electrophoresis (34%), autoimmune screen (22%), computed tomography (34%), chest X-ray (13%) and bone marrow aspirate (9%). Histology demonstrated a histiocytoid subtype in 10 cases of which 6 were classed as MASS, all of haematological origin. Ten patients were treated with topical corticosteroid only, 38 received oral prednisolone [median dose 30 mg (interquartile range 25–35; mean duration 29 40 weeks)] and 12 dapsone. Other medications included sulfapyridine (two), potassium iodide (two), colchicine (one), antibiotics (two), ciclosporin (one) and mycophenolate mofetil (one) with variable response. Fifty-one patients were followed-up for an average of 13 18 months with 7 6 visits per patient. Over half of SS cases were not categorized. Considerable variations were observed in investigations and follow-up irrespective of whether a cause was initially identified. The subsequent diagnoses of malignancy in patients with an originally unclear aetiology suggest the need for clearer guidelines regarding categorization, investigations for potential triggers and duration of follow-up.