title: Congenital cholesteatoma of mastoid region manifesting as acute mastoiditis: case report and literature review.
abstract: OBJECTIVE
  We report an extremely rare case of congenital cholesteatoma of the mastoid region, presenting as acute mastoiditis. We also review the 16 previously reported cases of congenital cholesteatoma of the mastoid region.
  
  
  METHODS
  A 65-year-old man presented with left-sided, post-auricular swelling and pain. Acute mastoiditis was diagnosed, with computed tomography demonstrating destruction of the bony plates of the posterior cranial fossa and sigmoid sinus. Initial surgery revealed a cholesteatoma in the mastoid, with no extension into the aditus ad antrum or attic. These findings were confirmed by pathological and immunohistochemical analysis of the surgical specimen, the latter using involucrin. The cholesteatoma matrix was completely removed in a second operation.
  
  
  CONCLUSIONS
  Including this case, only four of the 17 reported cases of congenital cholesteatoma of the mastoid region showed post-auricular pain or swelling, indicating acute mastoiditis. Clinicians should bear in mind that congenital cholesteatoma may be present in patients presenting with mastoiditis, particularly adults.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Tohoku University Graduate School of Medicine, Sendai, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Hidaka
authors.forename: E
authors.initials: E
authors.lastname: Ishida
authors.forename: K
authors.initials: K
authors.lastname: Kaku
authors.forename: H
authors.initials: H
authors.lastname: Nishikawa
authors.forename: T
authors.initials: T
authors.lastname: Kobayashi
mesh_terms: D000368:Aged; D018424:Cholesteatoma, Middle Ear / Q000151:congenital* / Q000601:surgery; D006801:Humans; D008297:Male; D008416:Mastoid / Q000601:surgery; D008417:Mastoiditis / Q000209:etiology* / Q000601:surgery; D014057:Tomography, X-Ray Computed