title: [Spontaneous rupture of a simple renal cyst to the pyelocalyceal system. Evolution from Bosniak I to IIF].
abstract: OBJECTIVE
  To report the spontaneous rupture of a renal cyst into the adjacent pyelocalyceal collecting system.
  
  
  METHODS
  We present the case of a 47 year old woman with a 17 centimeter simple renal cyst (Bosniak I) as well as ipsilateral nephrolithiasis. The patient had a febrile urinary tract infection with flank pain. A subsequent CT scan revealed that this cyst spontaneously ruptured into the renal pelvis.
  
  
  RESULTS
  Follow up evaluations showed the former cyst has decreased in size and contain thick and nodular calcifications. At present it is a Bosniak IIF cyst.
  
  
  CONCLUSIONS
  Simple renal cysts can spontaneously rupture and drain into the adjacent renal collecting system.
authors.affiliation: Servicio de Urología, Hospital Comarcal de Laredo, Laredo, Cantabria, España. a.h.castrillo@telefonica.net
authors.forename: Alberto
authors.initials: A
authors.lastname: Hernández Castrillo
authors.forename: Enrique
authors.initials: E
authors.lastname: de Diego Rodríguez
authors.forename: Miguel Angel
authors.initials: MA
authors.lastname: Rado Velázquez
authors.forename: José Manuel
authors.initials: JM
authors.lastname: Lanzas Prieto
mesh_terms: D002114:Calcinosis / Q000000981:diagnostic imaging; D003560:Cysts / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D007669:Kidney Calculi / Q000000981:diagnostic imaging; D007670:Kidney Calices / Q000000981:diagnostic imaging*; D052177:Kidney Diseases, Cystic / Q000000981:diagnostic imaging*; D007682:Kidney Pelvis / Q000000981:diagnostic imaging; D008875:Middle Aged; D011859:Radiography; D012422:Rupture, Spontaneous / Q000000981:diagnostic imaging