title: Rectal duplication cyst presenting as perianal sepsis: report of two cases and review of the literature.
abstract: BACKGROUND
  Recurrent perianal sepsis is a difficult problem to manage in colorectal surgical practice. One cause is rectal duplication cyst, a rare congenital lesion that is easily overlooked. Many cases have associated congenital defects, especially musculoskeletal anomalies, and may provide a clue to the underlying condition. Early diagnosis is important because these cysts do not resolve spontaneously and may undergo malignant change.
  
  
  METHODS
  We present two cases of middle-aged females who presented with perianal sepsis secondary to rectal duplication cyst. The first case had numerous surgical procedures for a perianal fistula during a ten-year period. She had associated sacral anomalies consistent with Currarino syndrome. The second case presented with a perineal mass after a bout of perianal inflammation. Both cases had the entire cyst surgically excised.
  
  
  RESULTS
  There were no complications postoperatively and no recurrence at follow-up. Histopathology revealed no malignancy in the cyst.
  
  
  CONCLUSIONS
  Rectal duplication cyst is a rare cause of recurrent perianal sepsis that should be considered in difficult cases, especially in those with associated musculoskeletal anomalies. Complete surgical excision is the preferred treatment to prevent recurrence and the risk of malignant degeneration.
authors.affiliation: University of Auckland, Department of Surgery, Auckland Public Hospital, Auckland, New Zealand.
authors.forename: Richard
authors.initials: R
authors.lastname: Flint
authors.forename: Jane
authors.initials: J
authors.lastname: Strang
authors.forename: Ian
authors.initials: I
authors.lastname: Bissett
authors.forename: Matthew
authors.initials: M
authors.lastname: Clark
authors.forename: Mischel
authors.initials: M
authors.lastname: Neill
authors.forename: Bryan
authors.initials: B
authors.lastname: Parry
mesh_terms: D000015:Abnormalities, Multiple / Q000175:diagnosis / Q000601:surgery; D000038:Abscess / Q000175:diagnosis / Q000209:etiology* / Q000601:surgery; D000328:Adult; D003560:Cysts / Q000151:congenital* / Q000175:diagnosis / Q000601:surgery; D005260:Female; D006618:Hip Dislocation, Congenital / Q000150:complications; D006801:Humans; D007668:Kidney / Q000002:abnormalities; D008279:Magnetic Resonance Imaging; D008591:Meningomyelocele / Q000150:complications; D008875:Middle Aged; D010146:Pain / Q000209:etiology; D018579:Patient Selection; D035583:Rare Diseases / Q000175:diagnosis / Q000601:surgery; D012002:Rectal Diseases / Q000175:diagnosis / Q000209:etiology* / Q000601:surgery; D012007:Rectum / Q000002:abnormalities*; D012008:Recurrence; D012307:Risk Factors; D012447:Sacrum / Q000002:abnormalities; D018805:Sepsis / Q000175:diagnosis / Q000209:etiology* / Q000601:surgery; D014057:Tomography, X-Ray Computed