title: Clinical, histopathological, and immunological evaluation of a series of patients with erythema nodosum.
abstract: BACKGROUND
  The pathogenesis of erythema nodosum (EN) is still poorly understood, and studies evaluating the involvement of a cytokine network are very scarce.
  
  
  OBJECTIVE
  To investigate clinical and pathological features, the cytokine profiles, and the balance of T-regulatory (Treg) and T-helper (Th)17 cells in serum and lesional skin of patients with EN.
  
  
  METHODS
  Patients with a diagnosis of EN were consecutively enrolled, and their clinical and histopathological features were recorded. A panel of cytokines was evaluated in both serum and lesional skin using enzyme-linked immunosorbent assay. Real-time polymerase chain reaction was performed to evaluate the Treg/Th17 cell balance.
  
  
  RESULTS
  Histopathological examination of skin biopsy specimens from all patients (four women and one man) showed classical features of EN. The most widely expressed cytokines were innate immunity cytokines (mainly tumor necrosis factor alpha, interleukin-8 and -6) and growth factors (mainly granulocyte colony-stimulating factor and monocyte chemoattractant protein-1). The Treg/Th17 balance was highly different between patients.
  
  
  CONCLUSIONS
  The present study emphasizes the crucial role of neutrophils in the pathogenesis of EN, as high levels of cytokines and growth factors mainly involved in neutrophil recruitment and activation were detected.
authors.affiliation: Department of Dermatology, Catholic University of the Sacred Heart, Rome, Italy.
authors.forename: Clara
authors.initials: C
authors.lastname: De Simone
authors.affiliation: Department of Dermatology, Catholic University of the Sacred Heart, Rome, Italy.
authors.forename: Giacomo
authors.initials: G
authors.lastname: Caldarola
authors.affiliation: Gastroenterology Division, "Policlinico A. Gemelli" Hospital, Catholic University of the Sacred Heart, Rome, Italy.
authors.forename: Franco
authors.initials: F
authors.lastname: Scaldaferri
authors.affiliation: Gastroenterology Division, "Policlinico A. Gemelli" Hospital, Catholic University of the Sacred Heart, Rome, Italy.
authors.forename: Valentina
authors.initials: V
authors.lastname: Petito
authors.affiliation: Department of Dermatology, Catholic University of the Sacred Heart, Rome, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Perino
authors.affiliation: Institute of Pathology, Catholic University of the Sacred Heart, Rome, Italy.
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Arena
authors.affiliation: Department of Surgical and Biomedical Sciences, Dermatologic Clinic of Terni, University of Perugia, Perugia, Italy.
authors.forename: Manuela
authors.initials: M
authors.lastname: Papini
authors.affiliation: Department of Surgery and Translational Medicine, Section of Dermatology, University of Florence, Florence, Italy.
authors.forename: Marzia
authors.initials: M
authors.lastname: Caproni
authors.affiliation: Department of Dermatology, Catholic University of the Sacred Heart, Rome, Italy.
authors.forename: Ketty
authors.initials: K
authors.lastname: Peris
mesh_terms: D000328:Adult; D001799:Blood Sedimentation; D002097:C-Reactive Protein / Q000378:metabolism; D018932:Chemokine CCL2 / Q000378:metabolism; D016207:Cytokines / Q000097:blood / Q000378:metabolism*; D004893:Erythema Nodosum / Q000276:immunology* / Q000378:metabolism / Q000473:pathology*; D005260:Female; D016179:Granulocyte Colony-Stimulating Factor / Q000378:metabolism; D006801:Humans; D015850:Interleukin-6 / Q000097:blood; D016209:Interleukin-8 / Q000097:blood; D018655:Lymphocyte Count; D008297:Male; D009504:Neutrophils; D050378:T-Lymphocytes, Regulatory; D058504:Th17 Cells; D014409:Tumor Necrosis Factor-alpha / Q000097:blood; D055815:Young Adult
chemical_list: D018932:Chemokine CCL2; D016207:Cytokines; D015850:Interleukin-6; D016209:Interleukin-8; D014409:Tumor Necrosis Factor-alpha; D016179:Granulocyte Colony-Stimulating Factor; D002097:C-Reactive Protein