title: Acanthamoeba infection in an interhemispheric ependymal cyst: a case report.
abstract: BACKGROUND
  Free-living amoebae are known to cause fatal granulomatous encephalitis in immunocompromised individuals. They are also known to present as multifocal parenchymal lesions, pseudotumoral lesions, meningeal exudates, hemorrhagic infarcts, and necrosis in the brain. However, Acanthamoeba infection in an intracranial ependymal cyst has not been reported in the literature.
  
  
  METHODS
  A 25-year-old immunocompetent man presented with a suspected interhemispheric arachnoid cyst. The cyst fluid turned out be infected with Acanthamoeba. The patient was treated successfully with decompression of the cyst with combination chemotherapy.
  
  
  CONCLUSIONS
  Acanthamoeba may cause secondary infection in an underlying brain cyst. A suspicion of such an infection must be raised in the presence of altered nature of CSF consistency. The aggressive chemotherapy is the only hope for favorable outcome. The dilemmas associated with the diagnosis and treatment are further discussed.
authors.affiliation: Department of Neurosurgery, St Stephen's Hospital, New Delhi 110054, India. rakeshr1@hotmail.com
authors.forename: Rakesh
authors.initials: R
authors.lastname: Ranjan
authors.forename: Amit
authors.initials: A
authors.lastname: Handa
authors.forename: Ajay
authors.initials: A
authors.lastname: Choudhary
authors.forename: Sushil
authors.initials: S
authors.lastname: Kumar
mesh_terms: D000048:Acanthamoeba / Q000302:isolation & purification*; D000328:Adult; D000562:Amebiasis / Q000175:diagnosis* / Q000469:parasitology; D000818:Animals; D000981:Antiprotozoal Agents / Q000627:therapeutic use; D020863:Central Nervous System Cysts / Q000469:parasitology*; D020808:Central Nervous System Protozoal Infections / Q000175:diagnosis* / Q000469:parasitology; D004805:Ependyma / Q000473:pathology*; D004830:Epilepsy, Tonic-Clonic / Q000469:parasitology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D014057:Tomography, X-Ray Computed
chemical_list: D000981:Antiprotozoal Agents