Galactomannan Detection In Bronchoalveolar Lavage Fluid Research Articles

Diagnostic value of galactomannan in serum and bronchoalveolar lavage fluid for invasive pulmonary aspergillosis in non-neutropenic patients

Objective: To evaluate the diagnostic performance of galactomannan (GM) detection in serum and bronchoalveolar lavage fluid (BALF) for invasive pulmonary aspergillosis (IPA) in non-neutropenic patients. Methods: A total of 291 non-neutropenic patients in the Second Xiangya Hospital of Central South University were included. According to the 2019 EORTC/MSG guidelines, all cases were divided into an IPA group (n = 24) and a non-IPA group (n = 267). Receiver operating characteristic (ROC) curves were drawn to compare the diagnostic efficiency of GM detection in BALF and serum. Results: According to the receiver operating characteristic curves of BALF and serum GM, the areas under the curve were 0.961 and 0.699, respectively. The optimal BALF GM detection was found when the cutoff value was set to 0.87, whereas the sensitivity and specificity were 91.7% and 92.5%, respectively. Conclusions: BALF GM detection is more sensitive than serum GM detection for diagnosing IPA, and the optimal cutoff value for BALF GM is 0.87.

Galactomannan in Bronchoalveolar Lavage Fluid for Diagnosis of Invasive Pulmonary Aspergillosis with Nonneutropenic Patients.

Background We evaluated the utility of galactomannan (GM) in bronchoalveolar lavage fluid (BALF) for the diagnosis of invasive pulmonary aspergillosis (IPA) in nonneutropenic patients. Methods A total of 183 patients were included in the final analysis. Bronchoscopies and the detection of GM in BALF were all performed on them. Results Ten cases of IPA were diagnosed. ROC data demonstrated that, for diagnosing IPA, an optimal cutoff value for GM in BALF of 0.76 yielded a sensitivity of 100.0% and a specificity of 76.2%. Symptoms and radiological findings had no significant difference between proven or probable IPA group and non-IPA group. In our case-control analysis, although nine patients with false-positive results received treatment with Piperacillin/tazobactam, there was no significant difference between case and control group. Conclusions BALF GM detection is a valuable adjunctive diagnostic tool. Our retrospective study suggests that the optimal value of GM detection in BALF is 0.76 in nonneutropenic patients.

Detection of galactomannan in bronchoalveolar lavage of the intensive care unit patients at risk for invasive aspergillosis.

Background and Purpose:Invasive aspergillosis (IA) is one of the most common life-threatening fungal infections among the critically ill patients including intensive care unit (ICU) patients. Delayed diagnosis and therapy may lead to poor outcomes. Diagnosis may be facilitated by a test for molecular biomarkers, i.e. detection of galactomannan (GM) antigen based on enzyme immunoassay, which is of increasing interest in the clinical settings for the diagnosis of IA. In the present study, we assessed GM testing of bronchoalveolar lavage (BAL) fluid as a tool for early diagnosis of IA among ICU patients who were at risk for developing IA.Material and Methods:A prospective study was performed in ICU patients with underlying predisposing conditions for IA between August 2010 and September 2011. BAL samples for direct microscopic examination, culture, and GM detection were obtained once or twice weekly. GM in BAL levels was measured using the Platellia Aspergillus EIA test kit. According to modified European Organization for the Research and Treatment of Cancer/ Mycoses Study Group (EORTC/MSG) criteria, patients were classified as having probable or possible IA.Results:Out of 43 suspected patients to IA, 13 (30.2%) cases showed IA. According to the criteria presented by EORTC/MSG, they were categorized as: 4 cases (30.8%) of possible IA and 9 (69.2%) of probable IA. Out of 21 BAL samples from patients with IA, 11 (52.4%) had at least one positive BAL GM index. Using a cutoff index of 0.5, the sensitivity and specificity, positive and negative predictive values of GM detection in BAL fluid were 100%, 85.7%, 65.7% and 96%, respectively. The sensitivity and specificity was 73% and 92.7% at cutoff ≥1.0, respectively. In 6 of 13 IA cases, BAL culture or direct microscopic examination remained negative, whereas GM in BAL was positive. Conclusion:Our data have revealed that the sensitivity of GM detection in BAL was better than that of conventional tests. It seems that GM detection in BAL is beneficial to establish or exclude the early diagnosis of IA in ICU patients.

Bronchoalveolar lavage fluid galactomannan detection for diagnosis of invasive pulmonary aspergillosis in chronic obstructive pulmonary disease

Invasive pulmonary aspergillosis (IPA) is difficult to diagnose in chronic obstructive pulmonary disease (COPD). The aim of this study was to evaluate whether detection of galactomannan (GM) in bronchoalveolar lavage fluid (BALF) might be a useful means of making the diagnosis. Patients with COPD and new pulmonary infiltrates were enrolled. BALF was collected for culture and detection of GM. Venous blood was also sampled for GM detection. Biopsy samples were obtained whenever possible. Eleven cases of IPA were diagnosed (three proven and eight probable); 80 controls without IPA diagnosed were recruited. At a GM cut-off of 0.5, the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for diagnosing IPA were 90.9, 66.3, 27.0 and 98.1% in serum, and 90.9, 62.5, 25.0 and 98.0% in BALF, respectively. At a cut-off of 1.0, the specificity, PPV and NPV in BALF increased to 95.0, 71.4 and 98.7%; the sensitivity remained 90.9%. The sensitivity in serum was substantially lower than BALF (45.5% versus 90.9%). Receiver operating characteristic curve analysis identified an optimal BALF GM cut-off value of 1.25, with a sensitivity of 90.9% and a specificity of 96.3% for diagnosing IPA. At a relatively high cut-off value, BALF GM detection is a useful tool for the diagnosis of IPA in COPD. Besides piperacillin-tazobactam and amoxicillin-clavulanate, many other factors may also cause false-positive of GM detection in patients without IPA. Further work is needed to identify factors that might lead to false-positive or false-negative results.

A prospective comparison of galactomannan in bronchoalveolar lavage fluid for the diagnosis of pulmonary invasive aspergillosis in medical patients under intensive care: comparison with the diagnostic performance of galactomannan and of (1→ 3) – β – d-glucan chromogenic assay in serum samples

Diagnosis of fungal pneumonia (FP) in critically ill patients is challenging. Circulating biomarkers for the diagnosis of FP have limitations and the combination of different assays in serum samples and directly from the target organ may further improve the diagnosis of FP. We prospectively assessed the diagnostic utility of paired galactomannan (GM) in bronchoalveolar lavage fluid (BAL) and serum GM and (1→3)–β–d-glucan (BG) assays in critically ill patients at risk of FP. Patients with FP were classified according to European Organisation for Research and Treatment of Cancer-Mycoses Study Group criteria, with modifications. Out of 847 admissions, 51 patients were eligible. There were nine invasive aspergillosis (IA) cases (four proven, five probable), three proven Pneumocysitis jirovecii pneumonia (PJP) cases and one mixed FP case (probable IA and proven PJP). The diagnostic accuracy as given by the area under the receiver operating characteristic curve in IA cases (proven and probable) for GM in BAL was 0.98 (95% CI, 0.94–1.00), whilst for GM and BG in serum it was 0.85 (95% CI, 0.74–0.96) and 0.815 (95% CI, 0.66–0.96), respectively. For IA cases (proven and probable) AUC for GM in BAL was significantly higher than GM and BG in serum (p 0.025 and p 0.032, respectively). In one of four proven and one of six probable IA cases, GM in serum remained negative, whereas GM in BAL was positive. In patients with IA, GM (90%) and BG (80%) appeared a mean of 4.3 days (range, 1–10 days) before Aspergillus was cultured. GM detection in BAL appears to improve the diagnosis of IA in critical patients.

Bronchoalveolar Lavage Fungal Antigen Detection in Critically Ill Children

Bronchoalveolar Lavage Fungal Antigen Detection in Critically Ill Children

A Novel Non-Invasive Method of Detecting Galactomannan in Suspected Pulmonary Aspergillosis.

Invasive pulmonary aspergillosis (IPA) is now the leading cause of infectious mortality in stem cell transplant recipients. Despite recent advances in molecular diagnostic techniques the diagnosis remains problematic. The mycological yield from bronchoalveolar lavage (BAL) is poor, especially if the patient has been exposed to antifungal drugs. Galactomannan (GM), a component of Aspergillus' cell wall is detectable in serum and BAL fluid in IPA, though its role in the latter has not been validated. Exhaled breath condensate (EBC) collection provides a non-invasive means of sampling the airway lining fluid. This method has been used in respiratory disease to detect markers of inflammation and oxidative stress. EBC is collected by breathing into a tube surrounded by a cooled insulated metal sleeve (RTube®, Respiratory Research, USA) and results in 1–2 millilitres of fluid. The application of EBC detection of volatile and non-volatile organic compounds has not been explored in this setting. We report on pilot data of the detection of GM in EBC from a subset of patients at high risk of infection forming part of a prospective study into the early diagnosis of IPA in allogeneic transplant recipients and patients with acute leukaemia. Patients were recruited prior to commencing treatment for their underlying haematological condition; the study period finished at neutrophil recovery (> 0.5 x 109/L) or discharge from hospital. EBC and serum were collected once and twice weekly respectively, throughout the study period. High resolution CT (HRCT) imaging of the chest was carried out after 72 hours of neutropenic fever unresponsive to broad-spectrum antibiotics. Where possible, BAL was carried out in the most affected lobe in patients with an abnormal HRCT chest. GM was measured in EBC, serum and, where applicable, BAL fluid using a commercially available kit (Platelia® Aspergillus, Bio-Rad, France). The likelihood of IPA was assigned using criteria published by European Organisation for Research and Treatment of Cancer/Mycoses Study Group (EORTC/MSG) by 2 investigators blinded to clinical details (Ascioglu et al, CID 2002). Of 39 patients, 6 had proven/probable IPA, 9 possible and 24 had no evidence of IPA. Four of the 6 patients with proven/probable disease had GM-positive BAL fluid; 3 of these 4 had persistently negative GM in serum. In 1 of the 6, the EBC GM was positive 3 weeks earlier than the development of HRCT evidence of IPA and a positive BAL GM. In another, the EBC GM was positive early in the infection, whilst BAL GM remained negative. EBC and serum GM followed the same trend in all 6 patients, although the values for both EBC and serum remained below the currently recognised positive cut-off of 0.5 in 2 patients. In patients with possible or no evidence of IPA, GM was negative in all but 2 of 111 EBC samples. These results suggest that GM can be detected in EBC and follows the same trend as in serum. It may even predate GM detection in BAL fluid or abnormal HRCT signs, thereby obviating the need for more invasive investigations. Elevated EBC GM levels early in the course of neutropenia may represent infection and could be applied to the employment of pre-emptive treatment strategies.

Galactomannan in Bronchoalveolar Lavage Fluid

Invasive aspergillosis (IA) is an important cause of mortality in patients with hematologic malignancies. However, IA appears to be gaining a foothold in the intensive care unit (ICU) in patients without classical risk factors. A recent study described 89 cases of IA in patients in a medical ICU without leukemia or cancer. The diagnosis of IA remains difficult and is often established too late. Galactomannan (GM) is an exo-antigen released from Aspergillus hyphae while they invade host tissue. This prospective single-center study was conducted to investigate the role of GM in bronchoalveolar lavage (BAL) fluid as a tool for early diagnosis of IA in the ICU. All patients with risk factors identified in our earlier study were evaluated. BAL for culture and GM detection, serum GM levels, and computed tomography scan were obtained for all included patients with signs of pneumonia. Patients were classified as having proven, probable, or possible IA. A total of 110 patients out of 1,109 admissions were eligible. There were 26 proven IA cases. Using a cutoff index of 0.5, the sensitivity and specificity of GM detection in BAL fluid was 88 and 87%, respectively. The sensitivity of serum GM was only 42%. In 11 of 26 proven cases, BAL culture and serum GM remained negative, whereas GM in BAL was positive. IA is common in immunocompromised, critically ill patients. GM detection in BAL fluid seems to be useful in establishing or excluding the diagnosis of IA in the ICU.