265. Performance of (1,3)-?- D- Glucan in Bronchoalveolar Lavage of Lung Transplant Recipients for the Diagnosis of Invasive Aspergillosis
Session: Poster Abstract Session: Diagnostic Microbiology; Novel Molecular Methods
Thursday, October 3, 2013
Room: The Moscone Center: Poster Hall C
Posters
  • BDG in LTR.pdf (282.9 kB)
  • Background: (1, 3)-β-d-glucan (BDG) is a constituent of the cell wall of fungi. This antigen has been studied as a marker of invasive fungal infection in serum; however its presence in bronchoalveolar lavage (BAL) fluid has not been well studied.

    Methods: Ninety four BAL samples available from 57 lung transplant recipients were processed for BDG using the commercially available Fungitell assay (Associates of Cape Cod Inc, Falmouth, MA, USA). Definitions of invasive aspergillosis (IA) were adopted from ISHLT and EORTC/MSG criteria. The generalized estimating equations regression was used to construct the receiver operator characteristic (ROC) curve to derive the optimum cut-off for sensitivity, specificity, positive and negative likelihood ratios.

    Results: Of the 94 events, 4 met the definition for probable IA and 15 had respiratory Aspergillus spp. colonization. The optimum cut-off of BDG for the diagnosis of IA was 102 pg/ml with a sensitivity, specificity, positive, negative likelihood ratios and AUC of 75%, 70%, 2.5, 0.36 and 0.72 (asymptotic 95% CI 0.5-0.9) respectively (Figure 1). Bronchoalveolar lavage BDG at this cut-off correctly categorized patients with IA in 70% of the cases. Figure 2 displays the ROC curve when comparing invasive aspergillosis (4 episodes) vs. Aspergillus spp. colonization (15 episodes). Using an optimum cut-off of 107 pg/ml, the sensitivity, specificity, positive, negative likelihood ratios and AUC were 75%, 80%, 3.7, 0.31 and 0.78 (asymptotic 95% CI 0.6-1) respectively. Seventy nine percent of the cases were correctly classified as disease rather than colonization at this cut-off.

    Conclusion: Bronchoalveolar lavage (1,3)-β-d-glucan at a cut-off greater than 100 pg/ml seems appropriate in the diagnosis of IA in lung transplant recipients.

     

    Figure 1: Receiver operator characteristic (ROC) curve of (1, 3)-β-d-glucan in bronchoalveolar lavage for invasive aspergillosis in lung transplant recipients

     

     

     

    Figure 2: Receiver operator characteristic (ROC) curve of (1, 3)-β-d-glucan in bronchoalveolar lavage for invasive aspergillosis vs. respiratory Aspergillus colonization in lung transplant recipients

     

    Archana Bhaskaran, MD, Lianne Singer, MD, Tony Mazzulli, MD, Taisa Pipkin, Coleman Rotstein, MD and Shahid Husain, MD, MS, University Health Network, Toronto, ON, Canada

    Disclosures:

    A. Bhaskaran, None

    L. Singer, None

    T. Mazzulli, None

    T. Pipkin, None

    C. Rotstein, Astellas, Merck, Pfizer: Grant Investigator and Speaker's Bureau, Research grant and Speaker honorarium

    S. Husain, Astellas, Merck, Pfizer: Grant Investigator, Research grant

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