Laboratory Diagnosis

• What is the preferred specimen for diagnosing Acanthamoeba trophozoites and cysts in cases of brain involvement?

  CSF (Cerebrospinal fluid)
• Besides CSF, which other specimen can be examined to detect Acanthamoeba in cases of brain involvement?

  Brain tissue
• What is the specimen of choice for diagnosing Acanthamoeba infections of the eye?

  = Corneal scrapings
• What is used to culture suspected corneal scrapings for Acanthamoeba?

  = Non-nutrient agar plates seeded with gram-negative bacteria
• How can Acanthamoeba feeding on the bacteria be visualized and aid in identification?

  = Production of tracks on the agar
• Besides culture, what other method can be used to reveal Acanthamoeba in corneal scrapings?

  Histologic examination
• What staining method can be used to visualize Acanthamoeba cysts in corneal scrapings?

  Calcofluor white staining
• What is the preferred technique for speciating Acanthamoeba?

   Indirect immunofluorescent antibody staining
• True or False: CSF is the preferred specimen for diagnosing Acanthamoeba infections of the eye.

  False
• True or False: Non-nutrient agar plates are seeded with gram-positive bacteria for the culture of suspected Acanthamoeba corneal scrapings.

  False