title: Comparison of microscopy, culture, and conventional polymerase chain reaction for detection of blastocystis sp. in clinical stool samples.
abstract: We tested 513 stool samples from patients in Sydney, Australia for Blastocystis by using five diagnostic techniques: microscopy of a permanently stained smear using a modified iron-hematoxylin stain, two xenic culture systems (a modified Boeck and Drbohlav's medium and tryptone, yeast extract, glucose, methionine-9 medium), and two published conventional polymerase chain reaction methods specific for the small subunit ribosomal DNA. Ninety-eight (19%) samples were positive for Blastocystis in one or more of the diagnostic techniques. The PCR 2 method was the most sensitive at detecting Blastocystis with a sensitivity of 94%, and the least sensitive was microscopy of the permanent stain (48%). Subtype 3 was the most predominant subtype (present in 43% of samples assigned to this group). This study highlights the low sensitivity of microscopy when used as the sole diagnostic modality for detection of Blastocystis sp.
authors.affiliation: Department of Microbiology, SydPath, St. Vincent's Hospital, Sydney, Australia. troberts@stvincents.com.au
authors.forename: Tamalee
authors.initials: T
authors.lastname: Roberts
authors.forename: Joel
authors.initials: J
authors.lastname: Barratt
authors.forename: John
authors.initials: J
authors.lastname: Harkness
authors.forename: John
authors.initials: J
authors.lastname: Ellis
authors.forename: Damien
authors.initials: D
authors.lastname: Stark
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016844:Blastocystis / Q000235:genetics / Q000254:growth & development / Q000648:ultrastructure; D016776:Blastocystis Infections / Q000175:diagnosis* / Q000469:parasitology; D018929:Cell Culture Techniques / Q000379:methods; D002648:Child; D002675:Child, Preschool; D004396:Coloring Agents; D003470:Culture Media; D016054:DNA, Protozoan / Q000235:genetics; D005243:Feces / Q000469:parasitology*; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008853:Microscopy / Q000379:methods; D008875:Middle Aged; D016133:Polymerase Chain Reaction / Q000379:methods; D012680:Sensitivity and Specificity; D017422:Sequence Analysis, DNA; D055815:Young Adult
chemical_list: D004396:Coloring Agents; D003470:Culture Media; D016054:DNA, Protozoan