title: Low-low synovial vascular malformation of the knee (hemangiolymphangioma) - Case report
abstract: BACKGROUND
  Low-flow vascular malformation, which usually develops during the first stage of infancy, is a rare cause of recurrent effusion of the knee. History, laboratory and X-rays are usually non-specific.
  
  
  OBJECTIVE
  To describe a rare disease in pediatrics, emphasizing the correct classification and suspicion.
  
  
  METHODS
  A case is presented of a two-year-old patient with a history of effusion of the right knee who required multiple hospitalizations and antibiotic treatments. Laboratory work-up was normal. Plain X-rays of the knee revealed no bone changes. MR imaging reported low-flow vascular malformation. Surgical resection was performed, evidencing vascular lesion among the muscle fibers of the vastus lateralis of quadriceps until the capsule of the knee, as well as dissection of the fibers until the vastus lateralis of the right leg. Histology was consistent with low-flow vascular malformation. Due to the benign outcome and favorable evolution, an outpatient management was possible.
  
  
  CONCLUSIONS
  Although low-flow synovial vascular malformation is a rare disease among the pediatric population, it should be considered in the differential diagnosis of patients with repeated hemarthrosis and no history of either coagulopathy or hemophilia.
authors.affiliation: Pediatra, Hospital Pablo Tobón Uribe, Docente de la Universidad Pontificia Bolivariana, Colombia.. Electronic address: andreaparrab@gmail.com.
authors.forename: B Andrea
authors.initials: BA
authors.lastname: Parra
authors.affiliation: Pediatra, Unidad de Cancerología, Hospital Pablo Tobón Uribe, Colombia.
authors.forename: Z Natalia Andrea
authors.initials: ZN
authors.lastname: Valencia
authors.affiliation: Pediatra, Jefe del Departamento de Pediatría, Hospital Pablo Tobón Uribe, Colombia.
authors.forename: B David Andrés
authors.initials: BD
authors.lastname: Espinal
authors.affiliation: Pediatra, Hospital Pablo Tobón Uribe, Colombia.
authors.forename: A Isabel Cristina
authors.initials: AI
authors.lastname: Maya
mesh_terms: D002675:Child, Preschool; D003937:Diagnosis, Differential; D005260:Female; D006391:Hemangioma / Q000175:diagnosis* / Q000601:surgery; D006395:Hemarthrosis / Q000175:diagnosis; D006801:Humans; D007719:Knee Joint / Q000473:pathology*; D008202:Lymphangioma / Q000175:diagnosis*; D008279:Magnetic Resonance Imaging / Q000379:methods; D013583:Synovial Membrane / Q000473:pathology; D054079:Vascular Malformations / Q000175:diagnosis* / Q000601:surgery
keywords: Children; Knee; Low-Flow Vascular Malformation; Malformación vascular de bajo flujo; Venous; niños; rodilla; venosa