About this Journal Submit a Manuscript Table of Contents
Scientifica
Volume 2013 (2013), Article ID 459405, 29 pages
http://dx.doi.org/10.1155/2013/459405
Review Article

Laboratory Diagnosis of Invasive Aspergillosis: From Diagnosis to Prediction of Outcome

Mycology Reference Centre, Department of Microbiology, Leeds Teaching Hospitals Trust, Leeds LS1 3EX, UK

Received 15 October 2012; Accepted 14 November 2012

Academic Editors: J. R. Blazquez, G. Comi, and C.-Y. Hung

Copyright © 2013 Richard C. Barton. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Invasive aspergillosis (IA), an infection caused by fungi in the genus Aspergillus, is seen in patients with immunological deficits, particularly acute leukaemia and stem cell transplantation, and has been associated with high rates of mortality in previous years. Diagnosing IA has long been problematic owing to the inability to culture the main causal agent A. fumigatus from blood. Microscopic examination and culture of respiratory tract specimens have lacked sensitivity, and biopsy tissue for histopathological examination is rarely obtainable. Thus, for many years there has been a great interest in nonculture-based techniques such as the detection of galactomannan, β-D-glucan, and DNA by PCR-based methods. Recent meta-analyses suggest that these approaches have broadly similar performance parameters in terms of sensitivity and specificity to diagnose IA. Improvements have been made in our understanding of the limitations of antigen assays and the standardisation of PCR-based DNA detection. Thus, in more recent years, the debate has focussed on how these assays can be incorporated into diagnostic strategies to maximise improvements in outcome whilst limiting unnecessary use of antifungal therapy. Furthermore, there is a current interest in applying these tests to monitor the effectiveness of therapy after diagnosis and predict clinical outcomes. The search for improved markers for the early and sensitive diagnosis of IA continues to be a challenge.