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Current laboratory diagnostic methods for invasive fungal infection (IFI) in haemato-oncology patients are insensitive, resulting in late diagnosis and contributing to high mortality. In recent years, progress has been made in the development and evaluation of sensitive sero-diagnostic assays, including detection of genomic DNA sequences and fungal antigens, which aid in a rapid, early diagnosis of IFI. The sensitivity and specificity of the assays vary considerably between studies, highlighting the need to correlate serological results with conventional laboratory tests and clinical or radiological findings. As part of management protocols, these assays may help to confirm the diagnosis of suspected IFI; however, the impact on mortality from IFI may be greatest when they are used to screen high-risk patients. Persistently positive screening results could direct early aggressive antifungal therapy, guided further by radiological and microbiological findings combined with regular clinical review, while the excellent negative predictive value may allow treatment to be withheld in patients with antibiotic resistant neutropenic fever but no other signs of IFI. However, this pre-emptive approach requires evaluation in prospective randomized trials., (Copyright 2004 Blackwell Publishing Ltd)

Purpose of Review: The early treatment of invasive fungal infection is critical but is hampered by the non-specific nature of clinical and radiological signs and the insensitivity of current laboratory diagnostic methods. If mortality due to invasive fungal infection is to be reduced, new, preemptive therapeutic strategies, targeting those patients at highest risk, are required and these will depend on the development of rapid, sensitive diagnostic methods. Such methods have become available in the form of high-resolution computed tomography scanning and serological and molecular techniques and in this review the authors describe recent studies assessing the utility of these methods and consider their role in management strategies., Recent Findings: Sensitive assays for the detection of fungal DNA and antigens such as galactomannan and glucan have been prospectively evaluated in the clinical setting and enable identification of patients at an earlier stage of infection. However, the sensitivity and specificity of the assays vary considerably in different studies, depending on several factors including patient selection and clinical application of the test, and issues regarding the release and circulation of galactomannan and fungal DNA remain to be clarified., Summary: Rapid serological and molecular diagnostic methods facilitate the early diagnosis of invasive fungal infection and would appear to be most useful when used prospectively to screen high-risk patients. However, in order to determine the optimal approach to treatment it is essential that these tests are incorporated into management strategies and their impact on incidence of invasive fungal infection and clinical outcome evaluated in further clinical trials.

The article discusses mixed pulmonary fungal infection with Aspergillus fumigatus and Absidia corymbifera in a patient with relapsed acute myeloid leukaemia. A 19-year-old male with relapsed acute myeloid leukaemia developed pyrexia, pleuritic chest pain and haemoptysis during re-induction chemotherapy. Chest computed tomography scanning demonstrated widespread consolidation. Invasive fungal infection caused by more than one species is infrequently reported. Absidia corymbifera carries an 80% mortality and is resistant to voriconazole and the ecchinocandins.