Galactomannan detection in computerized tomography‐based broncho‐alveolar lavage fluid and serum in haematological patients at risk for invasive pulmonary aspergillosis

Abstract

Summary. We determined the value of galactomannan (GM) detection in computerized tomography (CT)-based broncho-alveolar lavage (BAL) fluid and serum for the diagnosis of invasive pulmonary aspergillosis (IPA) in haemato-oncological patients with neutropenia. CT of the thorax and BAL were performed systematically at predefined clinical indications. GM was determined by sandwich enzyme-linked immunosorbent assay; the clinicians were unaware of the results. Of 160 patients, 17 patients (10AE6%) presented with proven, probable or suspected IPA. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of GM detection in CT-based BAL fluid were all 100%. For GM detection in serially sampled serum, the sensitivity was 47%, the specificity 93%, the PPV 73% and the NPV 82%. A non-blinded follow-up study was performed to validate these results. In this study, 22 of 198 patients (11AE1%) presented with IPA, and the sensitivity, specificity, PPV and NPV of GM detection in CT-based BAL fluid were 85%, 100%, 100% and 88% respectively. None of BAL fluids obtained after antifungal treatment of 3 d or more were positive. These results indicate that, when CT is used systematically and at an early stage, GM detection in CT-based BAL fluid has a high PPV for diagnosing IPA early in untreated patients.

Investigating the Presence of Aspergillus fumigatus and A. flavus Using Galactomannan Enzyme Assay and TaqMan Real-Time PCR Technique

“…GM-EIA sensitivity is decreased by antifungal treatment to 92%, while BAL fluid culture sensitivity has diminished to 16% by antifungal therapy. These outcomes are constant with the inspection that antifungal therapy might bring down the fungal burden in the lung tissue (12,(18)(19)(20). However, due to crossreactivity between GM antigen and some antibiotics (21)(22)(23)(24)(25)(26)(27)(28) in patients who receive these antibiotics, the result of the GM assay may be controversial.…”

“…In previous studies (7,(12)(13)(14), using a cut-off index of ≥ 1, the sensitivity and specificity values of GM detection in BAL fluid were 85% to 100% (14,15). Therefore, GMI 1.0 or greater in 2 consecutive samples was considered as positive in this study.…”

Invasive Aspergillosis in Intensive Care Unit Patients in Iran

“…However the Platelia Aspergillus GM EIA was designed to detect the presence of GM in serum samples but some authors suggested that it can be beneficial to detect GM in BAL fluid for IA diagnosis with high sensitivities and specificities (6,20,32). The previous studies (4,19,20) have shown that a GM index of ≥1.0 in comparison with 0.5 in BAL fluid enhances the diagnosis of IA in patients who are at risk; so in the present study, we used this GM index as a cutoff value for positive BAL GM.…”

Capítulo 1: diagnóstico laboratorial das micoses pulmonares

“…With a cut-off value between 1.0 and 1.5, sensitivity to galactomannan in BAL samples varied from 85% to 100% in most studies. (47)(48)(49) Another key factor for the efficacy of this technique is the prevalence of the disease in a specific population, which influences the positive predictive value observed. Consequently, the test to detect Aspergillus sp.…”