title: Comparison of four automated nucleic acid extraction platforms for the recovery of DNA from Aspergillus fumigatus.
abstract: Invasive aspergillosis is a significant cause of morbidity and mortality within at-risk groups. Directed antifungal chemotherapy, guided by effective screening algorithms that incorporate reliable and validated molecular assays, reduces the morbidity associated with empirical administration and allows earlier diagnosis. The efficient extraction of nucleic acid from Aspergillus fumigatus is the main limiting factor for successful Aspergillus PCR from clinical specimens. With the integration of automated extraction platforms, assessment of the suitability of these platforms for specific targets is of paramount importance. In this study, four extraction robots (Applied Biosystems MagMAX, bioMérieux easyMAG, Qiagen EZ1 and Roche MagNA Pure LC) were evaluated for their ability to extract clinically significant levels of A. fumigatus from blood. All of the platforms could detect 10(1) c.f.u. ml(-1) from EDTA whole blood, although only the easyMAG, EZ1 and MagNA Pure had 100 % reproducibility at this level. Despite good analytical sensitivity, contamination associated with the easyMAG platform excluded its use for diagnostic Aspergillus PCR. The EZ1 and MagNA Pure platforms demonstrated equivalent high sensitivity and negative predictive values (97.4-100 %), essential for screening assays.
authors.affiliation: Public Health Wales Microbiology Cardiff, University Hospital of Wales, Heath Park, Cardiff, UK.
authors.forename: Michael D
authors.initials: MD
authors.lastname: Perry
authors.affiliation: Public Health Wales Microbiology Cardiff, University Hospital of Wales, Heath Park, Cardiff, UK.
authors.forename: P Lewis
authors.initials: PL
authors.lastname: White
authors.affiliation: Department of Infection, Immunity and Biochemistry, Cardiff University, University Hospital of Wales, Heath Park, Cardiff, UK.
authors.forename: Rosemary A
authors.initials: RA
authors.lastname: Barnes
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001232:Aspergillus fumigatus / Q000235:genetics*; D057205:Automation, Laboratory / Q000379:methods; D002648:Child; D002675:Child, Preschool; D004271:DNA, Fungal / Q000302:isolation & purification*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013048:Specimen Handling / Q000379:methods*; D055815:Young Adult
chemical_list: D004271:DNA, Fungal