title: [Mammary duct ectasia in children: A case report].
abstract: BACKGROUND
  Bloody nipple discharge is an infrequent symptom during childhood. The most common cause in this population is mammary duct ectasia (MDE), which is a benign and self-limiting condition, that is characterized by dilatation of the mammary ducts, fibrosis and periductal inflammation.
  
  
  OBJECTIVE
  Report of a case of MDE in order to improve physicians' diagnosis accuracy and avoid aggressive studies and treatments.
  
  
  METHODS
  Six-months old male healthy infant, exclusively breastfeeded, that visited our clinic with a lump beneath his right nipple and bloody discharge from the same nipple. An ultrasound was performed which showed a multicystic lesion suggestive of MDE. Watchful waiting was decided as treatment, with good evolution after six months of follow up.
  
  
  CONCLUSIONS
  The MDE is the leading cause of bloody discharge in pediatric population, being a benign condition that resolves spontaneously before nine months. The knowledge of this condition is essential so as to accurately diagnose and treat it.
authors.affiliation: Departamento de Dermatología, Pontificia Universidad Católica de Chile, Santiago, Chile.
authors.forename: María Soledad
authors.initials: MS
authors.lastname: Zegpi
authors.affiliation: Departamento de Dermatología, Pontificia Universidad Católica de Chile, Santiago, Chile. Electronic address: camiladowney@gmail.com.
authors.forename: Camila
authors.initials: C
authors.lastname: Downey
authors.affiliation: Médico general, Universidad de los Andes, Santiago, Chile.
authors.forename: Verónica
authors.initials: V
authors.lastname: Vial-Letelier
mesh_terms: D001941:Breast Diseases / Q000175:diagnosis* / Q000473:pathology; D005122:Exudates and Transudates / Q000378:metabolism*; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D008297:Male; D042361:Mammary Glands, Human / Q000473:pathology*; D009558:Nipples / Q000378:metabolism*
keywords: Bloody nipple discharge, Children; Breast lump; Ectasia ductal mamaria; Mammary duct ectasia; Niños; Nódulo mamario; Telorragia