Nucleic Acid Sequence-Based Amplification of Aspergillus RNA in Blood Samples

Abstract

Nucleic acid sequence-based amplification (NASBA), an isothermal amplification technique, was established and evaluated for the detection of Aspergillus RNA and compared with a previously published, well-defined real-time PCR assay amplifying a region of the Aspergillus 18S rRNA gene. NASBA showed a lower detection limit of 1 CFU and detected RNA from five different clinically relevant Aspergillus species, including Aspergillus fumigatus . All 77 blood samples tested by PCR and NASBA showed identical results in both assays. Results with the NASBA technique were obtained within 6 h. Thus, the NASBA technique provided a valuable tool for sensitive, specific, fast, and reliable detection of Aspergillus RNA with potential for routine diagnosis, including the possibility to test the viability of cells.