title: Sweet Syndrome: Clinical Features, Histopathology, and Associations of 83 Cases.
abstract: BACKGROUND
  Sweet syndrome (SS) is an infrequent skin disease characterised by sudden onset of fever, leukocytosis, neutrophilia, and tender erythematous plaques infiltrated by neutrophils. Multiple conditions have been associated with this syndrome.
  
  
  OBJECTIVE
  The aim of this study was to evaluate the clinical, epidemiological, laboratory, and histopathological findings and associations of patients with SS.
  
  
  METHODS
  We conducted a retrospective study of 83 patients with SS followed between January 1, 2006, and January 31, 2015.
  
  
  RESULTS
  Of the patients, 82% were female; the mean age at onset was 48 years. Clinical presentation was mainly characterised by erythematous and edematous plaques, mostly on upper extremities and trunk. Fever was observed in 32%; 60% presented leukocytosis and 39% neutrophilia. On histopathological examination, neutrophilic and lymphohistiocytic infiltrate and edema were the most frequent findings. Fourteen percent of patients had malignancy or hematologic disorders, 26% were classified as having drug-induced SS, and 24% noted recent infection. Only 2 cases occurred during pregnancy. Systemic corticosteroid was the most common choice of treatment, with excellent response. In malignancy-associated SS, the mean hemoglobin level was lower ( P = .01) and the erythrocyte sedimentation rate (ESR) was higher ( P = .04) in comparison to classic and drug-induced SS. Leukocytoclasia was associated with higher risk of recurrence ( P = .01).
  
  
  CONCLUSIONS
  All patients with SS deserve careful investigation of possible underlying conditions. Higher ESR and lower hemoglobin levels might reinforce the need of malignancy screening. Also, leukocytoclasia appears to be a potential marker of higher recurrence rate, demanding closer and longer follow-up.
authors.affiliation: 1 Department of Dermatology, Hospital das Clínicas, University of São Paulo Medical School, Sao Paulo, SP, Brazil.
authors.forename: Jose Ricardo
authors.initials: JR
authors.lastname: Casarin Costa
authors.affiliation: 1 Department of Dermatology, Hospital das Clínicas, University of São Paulo Medical School, Sao Paulo, SP, Brazil.
authors.forename: Anangelica Rodrigues
authors.initials: AR
authors.lastname: Virgens
authors.affiliation: 1 Department of Dermatology, Hospital das Clínicas, University of São Paulo Medical School, Sao Paulo, SP, Brazil.
authors.forename: Luisa
authors.initials: L
authors.lastname: de Oliveira Mestre
authors.affiliation: 1 Department of Dermatology, Hospital das Clínicas, University of São Paulo Medical School, Sao Paulo, SP, Brazil.
authors.forename: Natasha Favoretto
authors.initials: NF
authors.lastname: Dias
authors.affiliation: 1 Department of Dermatology, Hospital das Clínicas, University of São Paulo Medical School, Sao Paulo, SP, Brazil.
authors.forename: Luciana Paula
authors.initials: LP
authors.lastname: Samorano
authors.affiliation: 1 Department of Dermatology, Hospital das Clínicas, University of São Paulo Medical School, Sao Paulo, SP, Brazil.
authors.forename: Neusa Yuriko Sakai
authors.initials: NYS
authors.lastname: Valente
authors.affiliation: 1 Department of Dermatology, Hospital das Clínicas, University of São Paulo Medical School, Sao Paulo, SP, Brazil.
authors.forename: Cyro
authors.initials: C
authors.lastname: Festa Neto
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000893:Anti-Inflammatory Agents / Q000627:therapeutic use; D002648:Child; D005121:Extremities / Q000473:pathology; D005260:Female; D006257:Head / Q000473:pathology; D006801:Humans; D007964:Leukocytosis; D008297:Male; D008875:Middle Aged; D011241:Prednisone / Q000627:therapeutic use; D012189:Retrospective Studies; D016463:Sweet Syndrome; D060726:Torso / Q000473:pathology; D055815:Young Adult
chemical_list: D000893:Anti-Inflammatory Agents; D011241:Prednisone
keywords: Sweet syndrome; drug-induced; erythematous plaques; fever; leukocytosis; neutrophilic dermatosis; paraneoplastic phenomenon