title: [Erythema nodosum: etiological changes in the last two decades].
abstract: OBJECTIVE
  To study the etiological factors associated with erythema nodosum in children hospitalized between January 1985 and December 2003.
  
  
  METHODS
  We performed a retrospective, descriptive study through review of the medical records of children with a diagnosis of erythema nodosum (MBDS-ICD 9-CM, code 6952). Forty-five patients (27 boys and 18 girls) aged between 10 months and 14 years were studied. The following variables were analyzed: age, sex, associated symptoms, complementary investigations (blood count, erythrocyte sedimentation rate, throat swab, chest x-ray, Mantoux test, ASLO titer, stool culture, serology) and final diagnosis.
  
  
  RESULTS
  The most frequent etiology was tuberculosis (10 patients), followed by Salmonella enteritidis (7 patients), group A beta -hemolytic Streptococcus (3 patients), Salmonella typhimurium (2 patients), Campylobacter jejuni (2 patients), Yersinia enterocolitica (1 patient), infectious mononucleosis caused by Epstein Barr virus (1 patient), cat scratch disease (1 patient), BCG vaccination (1 patient), associated chronic hepatitis B infection (1 patient), and associated amoxicillin treatment (1 patient). Etiology was unknown in 15 patients. The last case of erythema nodosum associated with tuberculous infection dated back to 1991, after which the most frequent etiologic factors associated with erythema nodosum were gastrointestinal pathogens.
  
  
  CONCLUSIONS
  According to our results, the main etiological factor currently associated with erythema nodosum is gastrointestinal infection. Consequently, stool cultures, especially when there are associated gastrointestinal symptoms, are essential.
authors.affiliation: Servicio de Pediatría, Hospital Donostia, San Sebastián, Guipúzcoa, Spain. isota@chdo.osakidetza.net
authors.forename: I
authors.initials: I
authors.lastname: Sota Busselo
authors.forename: E
authors.initials: E
authors.lastname: Oñate Vergara
authors.forename: E G
authors.initials: EG
authors.lastname: Pérez-Yarza
authors.forename: F
authors.initials: F
authors.lastname: López Palma
authors.forename: A
authors.initials: A
authors.lastname: Ruiz Benito
authors.forename: Y
authors.initials: Y
authors.lastname: Albisu Andrade
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D004893:Erythema Nodosum / Q000209:etiology* / Q000382:microbiology; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D012189:Retrospective Studies