Early diagnosis of invasive pulmonary aspergillosis in hematologic patients: an opportunity to improve the outcome

Using staged tree models for health data: Investigating invasive fungal infections by aspergillus and other filamentous fungi

Machine learning models are increasingly used in the medical domain to study the association between risk factors and diseases to support practitioners in understanding health outcomes. In this paper, we showcase the use of machine-learned staged tree models for investigating complex asymmetric dependence structures in health data. Staged trees are a specific class of generative, probabilistic graphical models that formally model asymmetric conditional independence and non-regular sample spaces. An investigation of the risk factors in invasive fungal infections demonstrates the insights staged trees provide to support medical decision-making.

Candent issues in pneumonia. Reflections from the Fifth Annual Meeting of Spanish Experts 2023

Pneumonia is a multifaceted illness with a wide range of clinical manifestations, degree of severity and multiple potential causing microorganisms. Despite the intensive research of recent decades, community-acquired pneumonia remains the third-highest cause of mortality in developed countries and the first due to infections; and hospital-acquired pneumonia is the main cause of death from nosocomial infection in critically ill patients. Guidelines for management of this disease are available world wide, but there are questions which generate controversy, and the latest advances make it difficult to stay them up to date. A multidisciplinary approach can overcome these limitations and can also aid to improve clinical results. Spanish medical societies involved in diagnosis and treatment of pneumonia have made a collaborative effort to actualize and integrate last expertise about this infection. The aim of this paper is to reflect this knowledge, communicated in Fifth Pneumonia Day in Spain. It reviews the most important questions about this disorder, such as microbiological diagnosis, advances in antibiotic and sequential therapy, management of beta-lactam allergic patient, preventive measures, management of unusual or multi-resistant microorganisms and adjuvant or advanced therapies in Intensive Care Unit.

Diagnostic performance of serum galactomannan and β-D-glucan for invasive aspergillosis in suspected patients: A meta-analysis

BACKGROUND

Serum galactomannan (GM) and β-D-glucan (BG) are known markers of invasive aspergillosis (IA). The aim of this meta-analysis was to evaluate the efficiency of serum GM and BG as diagnostic markers of symptomatic IA infection and compare the performance of the combined tests with that of either test individually.

METHODS

A literature search was carried out using PubMed, Web of Science, and EMBASE databases to include relevant studies published in English up to May 2023. The quality assessment was performed using Review Manager 5.3 software. A bivariate model was applied to pool diagnostic parameters using Stata 14.0 software. We used Cochrane I2 index to assess heterogeneity and identify the potential source of heterogeneity by meta-regression. Paired t tests were used to compare the value of GM and BG for IA diagnosis when used in combination or alone.

RESULTS

Sixteen studies were eligible for inclusion in the meta-analysis. For proven or probable IA, serum GM and BG yielded a pooled sensitivity of 0.53 (95% CI 0.40-0.66) vs 0.72 (95% CI 0.61-0.81) and a pooled specificity of 0.94 (95% CI 0.91-0.97) vs 0.82 (95% CI 0.73-0.88). The area under the curve (AUC) of ROC was 0.90 (95% CI 0.87-0.92) vs 0.83 (95% CI 0.80-0.86) for all studies. The pooled sensitivity and specificity for IA diagnosis by combined GM and BG assays (GM/BG) were 0.84 (95% CI 0.69-0.86) and 0.76 (95% CI 0.69-0.81), respectively. The sensitivity of the combined GM/BG test to diagnose IA was higher than of the GM or BG test alone.

CONCLUSION

Serum GM and BG tests had a relatively high accuracy for IA diagnosis in suspected patients. The diagnostic accuracy of both assays is comparable, and the diagnostic sensitivity is further improved by the combined detection of the 2 markers.

Atypical imaging patterns during lung invasive mould diseases: lessons for clinicians

Imaging of pulmonary invasive mould diseases (IMDs), which represents a cornerstone in their work-up, is mainly based on computed tomography (CT). The purpose of this review is to discuss their CT features, mainly those related to aspergillosis and mucormycosis. We will especially focus on atypical radiological presentations that are increasingly observed among non-neutropenic emerging populations of patients at risk, such as those receiving novel anticancer therapies or those in the intensive care unit. We will also discuss the interest of other available imaging techniques, mainly positron emission tomography/CT, that may play a role in the diagnosis as well as evaluation of disease extent and follow-up. We will show that any new airway-centred abnormality or caveated lesion should evoke IMDs in mildly immunocompromised hosts. Limitations in their recognition may be due to potential underlying abnormalities that increase the complexity of interpretation of lung imaging, as well as the non-specificity of imaging features. In this way, the differentials of all morphological/metabolic aspects must be kept in mind for the optimal management of patients, as well as the benefit of evaluation of the vascular status.

Radiology-based diagnosis of fungal pulmonary infections in high-risk hematology patients: are we making progress?

PURPOSE OF REVIEW

In patients with hematological malignancies, high-resolution computed tomography (CT) is the recommended imaging approach for diagnosis, staging and monitoring of invasive fungal disease (IFD) but lacks specificity. We examined the status of current imaging modalities for IFD and possibilities for more effective applications of current technology for improving the specificity of IFD diagnosis.

RECENT FINDINGS

Although CT imaging recommendations for IFD are largely unchanged in the last 20 years, improvements in CT scanner technology and image processing algorithms now allow for technically adequate examinations at much lower radiation doses. CT pulmonary angiography can improve both the sensitivity and specificity of CT imaging for angioinvasive molds in both neutropenic and nonneutropenic patients, through detection of the vessel occlusion sign (VOS). MRI-based approaches also show promise not only for early detection of small nodules and alveolar hemorrhage but can also be used to detect pulmonary vascular occlusion without radiation and iodinated contrast media. 18F-fluorodeoxyglucose (FDG) PET/computed tomography (FDG-PET/CT) is increasingly used to monitor long-term treatment response for IFD, but could become a more powerful diagnostic tool with the development of fungal-specific antibody imaging tracers.

SUMMARY

High-risk hematology patients have a considerable medical need for more sensitive and specific imaging approaches for IFD. This need may be addressable, in part, by better exploiting recent progress in CT/MRI imaging technology and algorithms to improve the specificity of radiological diagnosis for IFD.

Sequential low-dose CT thorax scans to determine invasive pulmonary fungal infection incidence after allogeneic hematopoietic cell transplantation

Invasive fungal disease (IFD) during neutropenia goes along with a high mortality for patients after allogeneic hematopoietic cell transplantation (alloHCT). Low-dose computed tomography (CT) thorax shows good sensitivity for the diagnosis of IFD with low radiation exposure. The aim of our study was to evaluate sequential CT thorax scans at two time points as a new reliable method to detect IFD during neutropenia after alloHCT. We performed a retrospective single-center observational study in 265/354 screened patients admitted for alloHCT from June 2015 to August 2019. All were examined by a low-dose CT thorax scan at admission (CT t₀) and after stable neutrophil recovery (CT t₁) to determine the incidences of IFD. Furthermore, antifungal prophylaxis medications were recorded and cohorts were analyzed for statistical differences in IFD incidence using the sequential CT scans. In addition, IFD cases were classified according to EORTC 2008. At CT t₀ in 9.6% of the patients, an IFD was detected and antifungal therapy initiated. The cumulative incidence of IFD in CT t₁ in our department was 14%. The use of Aspergillus-effective prophylaxis through voriconazole or posaconazole decreased CT thorax t₁ suggesting IFD is statistically significant compared to prophylaxis with fluconazole (5.6% asp-azol group vs 16.3% fluconazole group, p = 0.048). In 86%, CT t₁ was negative for IFD. Low-dose sequential CT thorax scans are a valuable tool to detect pulmonary IFDs and guide antifungal prophylaxis and therapies. Furthermore, a negative CT t₁ scan shows a benefit by allowing discontinuation of antifungal medication sparing patients from drug interactions and side effects.

Radiological patterns of pulmonary fungal infection in pediatric hematology and oncology patients

Abstract Objective: To describe the radiological findings in pediatric patients with hematological or oncological diseases who also have an invasive fungal infection (IFI). Materials and Methods: This was a retrospective study of all patients with IFI admitted to a pediatric hematology and oncology hospital in Brazil between 2008 and 2014. Clinical and demographic data were collected. Chest computed tomography (CT) scans of the patients were reviewed by two independent radiologists. Results: We evaluated the chest CT scans of 40 pediatric patients diagnosed with an IFI. Twenty-seven patients (67.5%) had nodules with the halo sign, seven (17.5%) had cavities, two (5.0%) had nodules without the halo sign, and seven (17.5%) had consolidation. The patients with the halo sign and cavities were older (123 vs. 77 months of age; p = 0.03) and had less severe disease (34% vs. 73%; p = 0.04). Ten patients had a proven IFI: with Aspergillus sp. (n = 4); with Candida sp. (n = 5); or with Fusarium sp. (n = 1). Conclusion: A diagnosis of IFI should be considered in children and adolescents with risk factors and abnormal CT scans, even if the imaging findings are nonspecific.

Two Monoclonal Antibodies That Specifically Recognize Aspergillus Cell Wall Antigens and Can Detect Circulating Antigens in Infected Mice

Invasive aspergillosis (IA) is a life-threatening disease mainly caused by Aspergillus fumigatus and Aspergillus flavus. Early diagnosis of this condition is crucial for patient treatment and survival. As current diagnostic techniques for IA lack sufficient accuracy, we have raised two monoclonal antibodies (1D2 and 4E4) against A. fumigatus cell wall fragments that may provide a platform for a new diagnostic approach. The immunoreactivity of these antibodies was tested by immunofluorescence and ELISA against various Aspergillus and Candida species in vitro and by immunohistochemistry in A. fumigatus infected mouse tissues. Both monoclonal antibodies (mAbs) showed intensive fluorescence with the hyphae wall of A. fumigatus and A. flavus, but there was no staining with other Aspergillus species or Candida species. Both mAbs also showed strong immunoreactivity to the cell wall of A. fumigatus hyphae in the infected liver, spleen and kidney of mice with IA. The antigens identified by 1D2 and 4E4 might be glycoproteins and the epitopes are most likely a protein or peptide rather than a carbohydrate. An antibody-based antigen capture ELISA detected the extracellular antigens released by A. fumigatus, A. flavus, A. niger and A. terreus, but not in Candida species. The antigen could be detected in the plasma of mice after 48 h of infection by double-sandwich ELISA. In conclusion, both 1D2 and 4E4 mAbs are potentially promising diagnostic tools to investigate invasive aspergillosis.

Invasive Fusariosis in Patients with Hematologic Diseases

Fusarium species are filamentous fungi widely encountered in nature, and may cause invasive disease in patients with hematologic conditions. Patients at higher risk are those with acute leukemia receiving induction remission chemotherapy or allogeneic hematopoietic cell transplant recipients. In these hosts, invasive fusariosis presents typically with disseminated disease, fever, metastatic skin lesions, pneumonia, and positive blood cultures. The prognosis is poor and the outcome is largely dependent on the immune status of the host, with virtually a 100% death rate in persistently neutropenic patients, despite monotherapy or combination antifungal therapy. In this paper, we will review the epidemiology, clinical manifestations, diagnosis, and management of invasive fusariosis affecting patients with hematologic diseases.

Invasive aspergillosis in critically ill patients: Review of definitions and diagnostic approaches

Invasive aspergillosis (IA) is an increasingly recognised phenomenon in critically ill patients in the intensive care unit, including in patients with severe influenza and severe coronavirus disease 2019 (COVID-19) infection. To date, there are no consensus criteria on how to define IA in the ICU population, although several criteria are used, including the AspICU criteria and new consensus criteria to categorise COVID-19-associated pulmonary aspergillosis (CAPA). In this review, we describe the epidemiology of IA in critically ill patients, most common definitions used to define IA in this population, and most common clinical specimens obtained for establishing a mycological diagnosis of IA in the critically ill. We also review the most common diagnostic tests used to diagnose IA in this population, and lastly discuss the most common clinical presentation and imaging findings of IA in the critically ill and discuss areas of further needed investigation.

Validation of the EQUAL Aspergillosis Score by analysing guideline-adherent management of invasive pulmonary aspergillosis

OBJECTIVES

To investigate the diagnosis and treatment standards at the University Hospital of Cologne, Germany, by applying the EQUAL Aspergillosis Score to invasive pulmonary aspergillosis (IPA) patients.

METHODS

The charts of 103 patients with probable or proven IPA at the University Hospital of Cologne were reviewed and the score retrospectively applied to all patients.

RESULTS

Patients were stratified into two groups according to the underlying disease: a haematology group (n = 76, 73.8%) and a non-haematology group (n = 27, 26.2%). While the haematology group attained 67.8% of achievable score points (median: 15; IQR: 13-18; range: 8-25), the non-haematology group reached 48.4% (median: 12 points; IQR: 9-14; range: 4-18) (P < 0.001). Regarding diagnostics, haematological patients achieved 81.3% of achievable points (median: 7; IQR: 8-10; range: 3-13) and non-haematological 56.3% (median: 7; IQR: 5-9; range: 3-11). Concerning treatment, haematological patients gained 86.3% (median: 5; IQR: 5-5; range: 0-5) and non-haematological 68.1% (median: 5; IQR: 0-5; range: 0-5) of achievable points. Among the haematological patients with versus those without mould-active prophylaxis, 90 day mortality was 46.0% and 59.3% (P = 0.004), respectively. Guideline adherent management of IPA was observed in 31.1% of cases (39.5% in haematological patients and 7.4% in non-haematological).

CONCLUSIONS

The EQUAL Aspergillosis Score is more suitable for evaluation of management of haematological patients compared with those without such underlying disease. In both groups there was no correlation between score points and survival. Larger prospective studies may be suitable to correlate outcome and score. A revision of the score should be considered based on the data presented.

Lipopolysaccharide Binding Protein and Bactericidal/Permeability-Increasing Protein as Biomarkers for Invasive Pulmonary Aspergillosis

Early diagnosis of invasive pulmonary aspergillosis (IPA) is crucial to prevent lethal disease in immunocompromized hosts. So far, lipopolysaccharide binding protein (LBP) and bactericidal/permeability-increasing protein (BPI) levels have not been evaluated as biomarkers for IPA. IL-8, previously introduced as a biomarker for IPA, was also included in this study. Bronchoalveolar lavage fluid (BALF) of IPA patients and control patients with non-infectious lung disease was collected according to clinical indications. Measurements in BALF displayed significantly higher levels of LBP (p < 0.0001), BPI (p = 0.0002) and IL-8 (p < 0.0001) in IPA compared to control patients. Receiver operating characteristic curve analysis revealed higher AUC for LBP (0.98, 95% CI 0.95–1.00) than BPI (0.84, 95% CI 0.70–0.97; p = 0.0301). Although not significantly different, AUC of IL-8 (0.93, 95% CI 0.85–1.00) also tended to be higher than AUC for BPI (p = 0.0624). When the subgroup of non-hematological patients was analyzed, test performance of LBP (AUC 0.99, 95% CI 0.97–1.00), BPI (AUC 0.97, 95% CI 0.91–1.00) and IL-8 (AUC 0.96, 95% CI: 0.90–1.00) converged. In conclusion, LBP and—to a lesser extend—BPI displayed high AUCs that were comparable to those of IL-8 for diagnosis of IPA in BALF. Further investigations are worthwhile, especially in non-hematological patients in whom sensitive biomarkers for IPA are lacking.

Detection of invasive pulmonary aspergillosis in mice using lung perfusion single-photon emission computed tomography with [99mTc]MAA

There is an urgent need for development of better diagnostic strategies to improve outcomes in patients with invasive pulmonary aspergillosis (IPA). We hypothesized that lung perfusion single-photon emission computed tomography (SPECT) may be more sensitive and specific than computed tomography (CT) of the chest for detection of IPA because it is an angioinvasive pulmonary infection with characteristics that are different from those of bacterial pneumonia. We used SPECT with injection of technetium-99m-labeled macroaggregated albumin ([99mTc]MAA) to measure pulmonary perfusion in noninfected mice, mice with IPA, and mice with bacterial pneumonia. Histopathologic analysis was performed to evaluate the correlation between the perfusion defect and mould invasion. We also attempted to quantitatively evaluate the SPECT images to identify differences in decreased perfusion levels in affected areas in the mouse lung. Histopathologic analysis in the IPA mouse model showed a clear match between areas with a perfusion defect and the presence of mold, indicating that the location of the perfusion defect on a SPECT image reflects angioinvasion of the mould in the lungs. Some of these perfusion defects could be seen before appearance of the infiltrate of CT images. Quantitative analysis confirmed that perfusion in the affected areas was significantly decreased in the IPA model but not in the bacterial pneumonia model (P < .0001). This imaging method may be preferable to the alternative methods presently used to identify the presence of mold in a patient's lungs.

Impact of invasive aspergillosis occurring during first induction therapy on outcome of acute myeloid leukaemia (SEIFEM-12B study)

BACKGROUND

Acute myeloid leukaemia (AML) patients are at high risk of invasive aspergillosis (IA) after first induction chemotherapy (CHT). Although IA risk factors have been identified, few data are available on impact of IA, occurring during induction phase, on overall AML outcome.

PATIENTS AND RESULTS

The end point of this multicentre, case-control, study was to evaluate whether IA, occurring after first induction CHT, can affect treatment schedule and patient's outcome. We identified 40 AML patients (cases) who developed IA during first induction phase, 31 probable (77.5%) and 9 proven (22.5%). These cases were matched with a control group (80 AML) without IA, balanced according to age, type of CHT, AML characteristics and cytogenetic-molecular risk factors. The overall response rate to induction CHT was the same in the 2 groups. In the 40 cases with IA, the overall response rate to antifungal treatment was favourable (80%) but it was significantly affected by the achievement of leukaemia complete remission (CR) with induction CHT. In fact, in cases with AML responsive to induction CHT, responses of IA to antifungal therapy were 96% compared to 21% in cases of AML not responsive to induction treatment (P < .0001). The adherence to the schedule and full doses of CHT were reported in 35% of cases (14/40) and in 76% of controls (61/80) (P = .0001; OR 6.7; 95% CI 2.7-16.6). After first induction CHT, a significant higher number of cases (15/40; 37.5%) compared to controls (9/80; 11%) could not receive additional cycles of CHT (P = .0011, OR 4.8; 95% CI 1.9-12.3). The IA-related mortality was 22.5%. The median OS of cases was significantly worse than OS of controls with a difference of 12.3 months (12.1 vs 24.4 months, P = .04). However, the occurrence of IA during first induction phase did not have a significant impact on the OS of cases who achieved a CR of AML with induction CHT which are able to proceed, despite the IA, with their therapeutic program, achieving the same OS as the control group with AML in CR (P = ns).

CONCLUSIONS

These data show that IA during first induction CHT can delay the subsequent therapeutic program and has a significant impact on OS, specifically in AML patients who did not achieved a CR of AML with the first course of CHT.

Airway-invasion-associated pulmonary computed tomography presentations characteristic of invasive pulmonary Aspergillosis in non-immunocompromised adults: a National Multicenter Retrospective Survey in China

Background

The European Organization for Research and Treatment of Cancer/Mycoses Study Group (EORTC/MSG) criteria are widely used in the diagnosis of invasive pulmonary aspergillosis (IPA), but they only apply to immunocompromised patients. We here aimed to identify clinical characteristics helpful to the diagnosis of IPA in non-immunocompromised patients.

Methods

This is a multicenter retrospective study. Data were collected from adult patients with IPA admitted to 15 tertiary hospitals in China from 2010 to 2016.

Results

We included 254 patients in the study, of whom 66 (26.0%) were immunocompromised, and 188 (74.0%) were not. Airway-invasion-associated computed tomography (CT) signs including patchy exudation along the airway (67.6% vs. 45.5%, P = 0.001) and thickened airway wall (42.0% vs. 16.7%, P < 0.001) were more common in non-immunocompromised patients than in immunocompromised ones, and angio-invasive CT signs were more common in immunocompromised patients (55.3% vs.72.7%, P = 0.013). Typical angio-invasive CT signs were delayed in non-immunocompromised IPA patients, whereas airway-invasive signs appear earlier. Host immunocompromised condition was associated with ICU admission and/or intubation (OR 1.095; 95% CI 1.461–6.122; P = 0.003). Poor prognosis (35.5% vs. 21.1%, P = 0.005) was more common in immunocompromised patients.

Conclusion

Airway-invasion-associated CT presentations at early stages of the disease are characteristic of IPA in non-immunocompromised hosts.

High prevalence of peribronchial focal lesions of airway invasive aspergillosis in hematological cancer patients with prolonged neutropenia

OBJECTIVE

The aim of this study is to characterize chest CT findings of neutropenic patients with proven/probable invasive pulmonary aspergillosis (IPA).

METHODS

Hematological cancer patients admitted to our institution (2007-2017) were retrospectively enrolled if the diagnostic criteria of proven/probable IPA during the neutropenia were met (EORTC/MSG). Galactomannan (GM) was routinely measured in serum and chest CT-scan was routinely performed in case of recurrent/persistent fever. Bronchoscopy was performed in case of chest CT-scan abnormalities. Chest CT-scan and GM dosage were analyzed at the time of IPA suspicion. Chest lesions were classified using a clinical report form by two expert radiologists.

RESULTS

35 patients were identified. Peribronchial focal lesions were observed in 29 IPA (82.9%) by the first radiologist and in 31 (88.5%) by the second (k = 0.768). 12 weeks mortality was 20%.

CONCLUSION

Peribronchial focal lesions are a common finding in early-IPA whatever the GM value during neutropenia and our findings reinforce the efficiency of a preemptive approach.

ADVANCES IN KNOWLEDGE;

Peribronchial focal lesions, which are classically described in airway invasive aspergillosis, are a common finding in early-IPA in hematological cancer patients with prolonged neutropenia regardless of the GM value, and such peribronchial lesions should reinforce the possibility of IPA.

Targeting novel genes for simultaneous detection of five fungal and bacterial agents from BAL samples using multiplex PCR assay

The main purpose of our study was to evaluate multiplex PCR assay targeting novel genes for detection of five fungal and bacterial agents in BAL samples; because many fungi and bacteria that cause respiratory infections have similar clinical symptoms, diagnosing and differentiating them are therefore essential to controlling and treating them. A total of 100 BAL specimens from a mycobacterium and mycology laboratory were collected from patients suspected of having TB or other respiratory diseases. Novel DNA targets for Aspergillus, Nocardia, Cryptococcus, and Streptomyces were found using modified comparative genomic analysis. Afterward, the primers were designed based on novel targets, and the sensitivity and specificity of the newly designed primers were evaluated. These primers, along with specific primers for M. tuberculosis (SDR), were used in a multiplex PCR assay. The results showed the culture test to be more sensitive than the PCR assay in detecting M. tuberculosis. However, in the detection of Aspergillus, the PCR assay was more sensitive than the culture test. We also found one positive culture and two positive PCR assays for Nocardiosis. Cryptococcal infections and Streptomyces associated with lung diseases were not identified by the culture test nor by the PCR assay. The multiplex PCR is one of the cheapest molecular diagnostic tests readily available for BAL samples in clinical laboratories. This assay can be used for early reports of the causative agents and for treating patients with appropriate drugs at an early stage.

Baseline Chest Computed Tomography as Standard of Care in High-Risk Hematology Patients

Baseline chest computed tomography (BCT) in high-risk hematology patients allows for the early diagnosis of invasive pulmonary aspergillosis (IPA). The distribution of BCT implementation in hematology departments and impact on outcome is unknown. A web-based questionnaire was designed. International scientific bodies were invited. The estimated numbers of annually treated hematology patients, chest imaging timepoints and techniques, IPA rates, and follow-up imaging were assessed. In total, 142 physicians from 43 countries participated. The specialties included infectious diseases (n = 69; 49%), hematology (n = 68; 48%), and others (n = 41; 29%). BCT was performed in 57% (n = 54) of 92 hospitals. Upon the diagnosis of malignancy or admission, 48% and 24% performed BCT, respectively, and X-ray was performed in 48% and 69%, respectively. BCT was more often used in hematopoietic cell transplantation and in relapsed acute leukemia. European centers performed BCT in 59% and non-European centers in 53%. Median estimated IPA rate was 8% and did not differ between BCT (9%; IQR 5–15%) and non-BCT centers (7%; IQR 5–10%) (p = 0.69). Follow-up computed tomography (CT) for IPA was performed in 98% (n = 90) of centers. In high-risk hematology patients, baseline CT is becoming a standard-of-care. Chest X-ray, while inferior, is still widely used. Randomized, controlled trials are needed to investigate the impact of BCT on patient outcome.

Diagnostic Performance and Safety of Bronchoalveolar Lavage in Thrombocytopenic Haematological Patients for Invasive Fungal Infections Diagnosis: A Monocentric, Retrospective Experience

Background

Although bronchoalveolar lavage (BAL) measurements of galactomannan antigen (GM) seems to be more sensitive than serum testing to detect invasive fungal infection (IFI), a consensus on the most appropriate diagnostic threshold of the BAL GM test is still unclear. Moreover, there is uncertainty as to whether BAL is a safe procedure in patients with hematological malignancies (HM) and thrombocytopenia.

Objectives

Based on this background, 102 adult patients with HM and associated thrombocytopenia were retrospectively analyzed with the dual aim of 1) determining whether BAL is a safe and feasible procedure; and, 2) identifying the most appropriate threshold for GM positivity in the diagnosis of IFI.

Patients/Methods

each BAL was considered as one case/patient. One hundred twelve BALs were carried out in 102 HM patients: at the time of the BAL, the median platelet count (PLTs) in all patients was 47×10⁹/L (1–476), and 31 patients (27%) had PLTs< 20×10⁹/L.

Results

complications from the BAL were infrequent (3.5%) and mild. No bleeding was reported. The BAL GM cut off of >0.8 was associated with the best diagnostic accuracy (sensitivity 72.97% and specificity 80%). Antifungal treatment of patients with BAL GM >0.8 resulted in a clinical-radiological improvement in 35/41 patients (85%).

Conclusions

BAL was a safe procedure also in thrombocytopenic patients, permitting an IFI diagnosis not otherwise identifiable using EORTC/MSG criteria. Our data suggest that a BAL GM value of>0.8 represents the most useful cut-off in terms of sensibility and specificity. Further prospective studies on a more significant number of patients are needed to confirm these results.

Beyond biomarkers: How enhanced CT imaging can improve the diagnostic-driven management of invasive mould disease

CT imaging remains an essential diagnostic test for identification, staging and management of invasive mould infection (IMI) in patients with hematological malignancies. Yet the limited specificity of standard CT imaging can drive excessive antifungal use in patients, especially when more definitive diagnosis cannot be established through microbiology or invasive diagnostic procedures. CT pulmonary angiography (CTPA) is a complimentary, non-invasive approach to standard CT that allows for direct visualization of pulmonary arteries inside infiltrates for signs of angioinvasion, vessel destruction and vessel occlusion. Experience from several centers that are using CTPA as part of a standard diagnostic protocol for IMI suggests that a positive vessel occlusion sign (VOS) is the most sensitive and a specific sign of IMI in both neutropenic and non-neutropenic patients. CTPA is particularly useful in patients who develop suspected breakthrough IMI during antifungal prophylaxis because, unlike serum and/or BAL galactomannan and polymerase chain reaction (PCR) testing, the sensitivity is not reduced by antifungal therapy. A negative VOS may also largely rule-out the presence of IMI, supporting earlier discontinuation of empirical therapy. Future imaging protocols for IMI in patients with hematological malignancies will likely replace standard chest X-rays in favor of early low radiation dose CT exams for screening, with characterization of the lesions by CTPA and routine follow-up using functional/metabolic imaging such as 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (FDG-PET/CT) to assess treatment response. Hence, enhanced CT imaging techniques can improve the diagnostic-driven management of IMI management in high-risk patients with hematological malignancies.

Invasive pulmonary aspergillosis in critically ill patients with hematological malignancies

PURPOSE

Invasive pulmonary aspergillosis (IPA) is a dreadful event in patients with hematological malignancies (HM). Recent advances have standardized diagnostic, prophylactic and curative therapeutic strategies. We sought to assess whether these advances actually translate into improved survival in critically ill patients with acute respiratory failure and IPA.

METHODS

This was a retrospective, multicenter study. Adult patients with HM, IPA, admitted to the ICU for acute respiratory failure over a 20-year period (January 1998-December 2017) were included. A cox regression model was used to identify variables independently associated with day-90 survival.

RESULTS

Overall, 219 patients were included [138 (63%) men, median age 55 (IQR 44-64)]. Acute myeloid leukemia (30.1%) and non-Hodgkin lymphoma (22.8%) were the most frequent malignancies, and 53 (24.2%) were allogeneic stem cell recipients. Day-1 SOFA score was 9 [7-12]. Most patients presented with probable IPA, whereas 15 (7%) underwent lung biopsies or pleurocentesis and met criteria for proven IPA. Overall ICU and day-90 mortality were, respectively, 58.4% and 75.2% (80.4% if invasive mechanical ventilation) without any significant improvement over time. By multivariable analysis adjusted on day-1 SOFA score and ventilation strategies, voriconazole use (HR 0.49, CI 95 0.34-0.73, p < 0.001) and an ICU admission after 2010 (HR 0.67, 0.45-0.99, p = 0.042) were associated with increased survival, whereas a diffuse radiologic pattern (HR 2.07, CI 95 1.33-3.24, p = 0.001) and delayed admission to the ICU (HR 1.51, CI 95 1.05-2.16, p = 0.026) were independently associated with increased mortality.

CONCLUSIONS

IPA is associated with high mortality rates in critically ill patients with acute respiratory failure. Routine voriconazole and prompt ICU admission are warranted.

β-1,6-linked Galactofuranose- rich peptidogalactomannan of Fusarium oxysporum is important in the activation of macrophage mechanisms and as a potential diagnostic antigen

A peptidogalactomannan (PGM) from Fusarium oxysporum was structurally characterized by a combination of chemical and spectroscopic methods, including one and two-dimensional nuclear magnetic resonance (1D and 2D NMR). The galactomannan component consists of a main chain containing (1→6)-linked β-D-galactofuranose residues with side chains containing (1→2)-linked α-D-Glcp, (1→2)-linked -β-D-Manp (1→2) and β-D-Manp terminal nonreducing end units and differs from that of Aspergillus fumigatus and Cladosporium resinae that present a main chain containing (1→6)-linked α-D-Manp residues presenting β-D-Galf as side chains of 3-4 units that are (1→5)-interlinked. The importance of the carbohydrate moiety of the F. oxysporum PGM was demonstrated. Periodate oxidation abolished much of the PGM antigenic activity. A strong decrease in reactivity was also observed with de-O-glycosylated PGM. In addition, de-O-glycosylated PGM was not able to inhibit F. oxysporum phagocytosis, suggesting that macrophages recognize and internalize F. oxysporum via PGM. F. oxysporum PGM triggered TNF-α release by macrophages. Chemical removal of O-linked oligosaccharides from PGM led to a significant increase of TNF-α cytokine levels, suggesting that their removal could exposure another PGM motifs able to induce a higher secretion of TNF-α levels. Interestingly, F. oxysporum conidia, intact and de-O-linked PGM were not able to induce IL-10 cytokine release. The difference in patient serum reativity using a PGM from F. oxysporum characterized in the present study as compared with a PGM from C. resinae, that presents the same epitopes recognized by serum from patients with aspergillosis, could be considered a potential diagnostic antigen and should be tested with more sera.

Invasive pulmonary aspergillosis in acute leukemia: a still frequent condition with a negative impact on the overall treatment outcome

We evaluated the impact of invasive pulmonary aspergillosis (IPA) on epidemiology and outcome in acute leukemia (AL), analyzing all acute myeloid (AML) and acute lymphoblastic leukemia (ALL) consecutively admitted to our Institution during a 5-year period of observation. Only AML patients received anti-mold prophylaxis. Among 175 AL patients (136 AML/39 ALL), possible and proven/probable IPA were diagnosed in 28 (16%). Frequency of IPA was similar in AML (16.2%) and in ALL (15.4%). Two-year overall survival (OS) was significantly affected by IPA (no IPA: 69.8% vs IPA: 31.7% p = .002). OS was similar in patients with proven/probable (28.2%) and possible IPA (36.4%) (p = .003 and .065, respectively). When censoring patients at transplant, IPA still affected 2-year survival (49.6% vs 79.2%, p = .02), but only proven/probable IPA was associated with lower survival (34.7%, p = .0003). IPA negatively impacts on long-term survival of leukemia patients; antifungal prophylaxis should be adopted also during induction in ALL and in AML beyond induction therapy.

The performance of galactomannan in combination with 1,3-β-D-glucan or aspergillus-lateral flow device for the diagnosis of invasive aspergillosis: Evidences from 13 studies

Galactomannan (GM), 1,3-β-D-glucan (BDG) and aspergillus-lateral flow device (LFD) are recognized as diagnostic tools for invasive aspergillosis (IA). The combined performance of these assays, however, is inconsistent in various studies. We undertook a meta-analysis of 13 studies involving 1513 patients to evaluate the utility of GM in combination with BDG or LFD for diagnosing IA. The pooled SEN, SPE, PLR, NLR and diagnostic odds ratio (DOR) were calculated and constructed to summarize the overall combined performance. Combining both positive results of GM and BDG assays leaded to the pooled SEN 0.49 (95%CI 0.27-0.72), SPE 0.98 (95%CI 0.94-1.00), PLR 31.68 (95%CI 5.36-187.37), NLR 0.52 (95%CI 0.32-0.84) and DOR 61.23 (95%CI 6.96-538.90). Comparing with GM and BDG assays, both positive results of GM and LFD leaded to high SEN, similar SPE, low PLR and NLR. At least one positive result of GM or LFD conferred great SEN 0.93 and low NLR 0.08. Both positive results of GM and BDG or LFD assay were in favor of confirming the existence of IA. And both negative results of GM and LFD were beneficial to rule out IA. Further studies with sufficient sample size should focus on the diagnostic performance and cost-effectiveness of these combined tests in clinical setting.

Invasive mould disease in haematologic patients: comparison between fusariosis and aspergillosis

OBJECTIVES

To compare the epidemiology, clinical presentation, diagnosis, treatment, and outcome of haematologic patients with invasive aspergillosis (IA) or invasive fusariosis (IF).

METHODS

We retrospectively reviewed the charts of 36 patients with IA and 26 with IF diagnosed between 2006 and 2017 in haematologic patients, and compared baseline characteristics, coexisting exposures, clinical manifestations, treatment, and the outcome.

RESULTS

Fever was more frequent in IF (96.2% vs. 63.9%, p 0.003), whereas pneumonia (88.9% vs. 50.0%, p 0.001) and sinusitis (63.9% vs. 38.5%, p 0.048) were more frequent in IA. Skin lesions and positive blood cultures occurred exclusively in patients with IF. Among patients with pneumonia, the halo sign was more frequent in IA (62.5% vs. 23.1%, p 0.02). Serum galactomannan was positive in 88.6% of patients with IA and in 73.3% with IF (p 0.18), with no differences in the median number of positive tests and galactomannan values. Positive serum galactomannan plus lung infiltrates was the predominant clinical presentation in IA and occurred in four of 13 patients with IF and lung involvement. The 30-day survival was 77.7% in IA and 46.1% in IF (p 0.01).

CONCLUSIONS

IA and IF share the same epidemiologic scenario but different clinical presentations in the majority of cases, with disease in the airways in IA, and fever, metastatic skin lesions, and positive blood cultures in IF. However, a substantial proportion of patients with IF present with a clinical picture similar to IA, with fever, lung infiltrates, and positive serum galactomannan.

Fungal infections in hematopoietic stem cell transplantation in children at a pediatric children's hospital in Argentina

Our primary objective was to describe the incidence of proven or probable invasive fungal infections (IFIs), a devastating complication of hematopoietic stem cell transplant (HSCT), in HCST in a middle-income country. Secondary objectives were to describe factors associated with IFIs and outcomes. In this single center retrospective study, pediatric patients who underwent a first allogeneic or autologous HSCT from 1998 to 2016 were included. Of the 251 HSCT recipients: 143 transplants were allogeneic and 108 were autologous. Overall, 23 (9%) experienced an IFI, mostly due to yeasts (83%). IFIs were more common in allogeneic HSCT (18/143, 13%) than in autologous HSCT (5/108, 5%; P = .045). Of the 23 patients with IFIs, 14 (61%) died, but only 1 directly from IFI (pulmonary aspergillosis). Overall survival at 3 years was 0.42 ± 0.11 in patients with IFIs and 0.60 ± 0.37 in those without IFIs (P = .049). In Argentina, IFIs during HSCT are common. Recipients of allogeneic HSCT are at higher risk, and IFI is associated with reduced overall survival. Future work should focus on interventions to reduce and improve IFI outcomes in children undergoing transplants in low- and middle-income countries.

The current management landscape: aspergillosis

Diagnosing invasive aspergillosis (IA) has long been challenging due to the inability to culture the causal Aspergillus agent from blood or other body fluids. This shortcoming has fuelled an interest in non-culture-based diagnostic techniques such as the detection of galactomannan (GM) in blood and bronchoalveolar lavage fluid, the detection of 1,3-β-d-glucan (BDG) in blood and the detection of Aspergillus DNA by PCR-based techniques. Past decades have witnessed important improvements in our understanding of the strengths and limitations of antigen assays and in the standardization of PCR-based DNA techniques. These assays are now being incorporated into care pathways and diagnostic algorithms; they help us to steward and monitor antifungal therapies and to predict treatment outcomes.

Invasive fungal infections: managing the continuum of risk in HCT patients

43rd Annual Meeting of the EBMT, 26-29 March 2017, Marseille, France The European Society for Blood and Marrow Transplantation (EBMT) was established in 1974 to enable scientists and physicians to share their experience and develop studies in clinical bone marrow transplantation. Despite advances in treatment, invasive fungal infections (IFI), especially those caused by moulds such as Aspergillus, remain a leading cause of morbidity and mortality in patients with hematological malignancies. There is a continuum of risk of IFI during induction and consolidation therapy, and after hematopoietic cell transplantation. New, evidence-based approaches to the prevention, diagnosis and treatment of IFI were, therefore, of major interest to the over 5000 delegates from 85 countries attending the 43rd EBMT Annual Meeting (EBMT 2017).

Clinical characteristics, radiologic findings, risk factors and outcomes of serum galactomannan-negative invasive pulmonary aspergillosis

BACKGROUND

The sensitivity of galactomannan (GM) assay is suboptimal for detecting invasive pulmonary aspergillosis (IPA) in serum samples. However, the clinical characteristics, radiologic findings, and outcomes in patients with GM-negative IPA have not been fully elucidated.

METHODS

Over a 7-year period, adult patients with proven or probable IPA by the EORTC/MSG definition were retrospectively enrolled. Patients with negative GM results and positive Aspergillus spp. cultures from sputum or bronchoalveolar lavage were classified into GM-negative IPA group. GM-positive and culture-negative IPA cases were selected at a 1:2 ratio.

RESULTS

Thirty-four patients with GM-negative IPA were compared to 68 randomly selected patients from 158 patients with GM-positive and culture-negative IPA. Patients with diabetes mellitus, chronic kidney disease, and steroid use were more common but those with hematologic malignancy, prior receipt of mold-active antifungal drugs, and neutropenia were less common in GM-negative IPA than in GM-positive IPA. Regarding radiologic findings, angioinvasive aspergillosis was less common in GM-negative IPA than in GM-positive IPA. The median number of days from diagnosis to appropriate antifungal therapy was higher in GM-negative IPA than in GM-positive IPA. Multivariate analysis indicated that neutropenia (adjusted odds ratio [aOR], 0.10) and prior receipt of mold-active antifungal drugs (aOR, 0.12) were inversely associated with GM-negative IPA. The 30-day and 90-day mortality were similar between the two groups.

CONCLUSION

Neutropenia and prior receipt of mold-active antifungal drugs before GM assay were independently associated with GM positivity among patients with proven/probable IPA. Angioinvasive aspergillosis was less common in GM-negative IPA than in GM-positive IPA.

Ecology of aspergillosis: insights into the pathogenic potency of Aspergillus fumigatus and some other Aspergillus species

Fungi of the genus Aspergillus are widespread in the environment. Some Aspergillus species, most commonly Aspergillus fumigatus, may lead to a variety of allergic reactions and life-threatening systemic infections in humans. Invasive aspergillosis occurs primarily in patients with severe immunodeficiency, and has dramatically increased in recent years. There are several factors at play that contribute to aspergillosis, including both fungus and host-related factors such as strain virulence and host pulmonary structure/immune status, respectively. The environmental tenacity of Aspergilllus, its dominance in diverse microbial communities/habitats, and its ability to navigate the ecophysiological and biophysical challenges of host infection are attributable, in large part, to a robust stress-tolerance biology and exceptional capacity to generate cell-available energy. Aspects of its stress metabolism, ecology, interactions with diverse animal hosts, clinical presentations and treatment regimens have been well-studied over the past years. Here, we synthesize these findings in relation to the way in which some Aspergillus species have become successful opportunistic pathogens of human- and other animal hosts. We focus on the biophysical capabilities of Aspergillus pathogens, key aspects of their ecophysiology and the flexibility to undergo a sexual cycle or form cryptic species. Additionally, recent advances in diagnosis of the disease are discussed as well as implications in relation to questions that have yet to be resolved.

Aspergillosis and stem cell transplantation: An overview of experimental pathogenesis studies

Invasive aspergillosis is a life-threatening infection caused by the opportunistic filamentous fungus Aspergillus fumigatus. Patients undergoing haematopoietic stem cell transplant (HSCT) for the treatment of hematological malignancy are at particularly high risk of developing this fatal infection. The susceptibility of HSCT patients to infection with A. fumigatus is a consequence of a complex interplay of both fungal and host factors. Here we review our understanding of the host-pathogen interactions underlying the susceptibility of the immunocompromised host to infection with A. fumigatus with a focus on the experimental validation of fungal and host factors relevant to HSCT patients. These include fungal factors such as secondary metabolites, cell wall constituents, and metabolic adaptations that facilitate immune evasion and survival within the host microenvironment, as well as the innate and adaptive immune responses involved in host defense against A. fumigatus.

Usage of 1,3-β-D-Glucan for Early Detection of Invasive Mycoses and Outcome Parameter in Immunocompromised Critically Ill Patients

INTRODUCTION

Invasive fungal disease (IFD) remains a significant cause of morbidity and mortality in critically ill patients.

METHODS

Examination of 1,3-β-D-glucan (BDG) for IFD and as outcome parameter in immunocompromised critically ill patients with septic shock.

RESULTS

Thirty-two (69 %) out of 46 included patients had BDG beyond the cutoff of >80 pg/ml (mean 320 pg/ml). Twelve (37 %) had findings of Aspergillus spp. in BAL (mean BDG 413 pg/ml). EORTC/MSG guidelines classified these as probable invasive aspergillosis (IA)/IFD. Five (16 %) had candidaemia (mean BDG level 361 pg/ml). Sensitivity of 78 % (95 % CI 58-88 %) and specificity of 68 % (95 % CI 52-77 %) for IFD were found on the BDG Fungitell assay. In detail, a sensitivity of 73 % (95 % 58-84 %) and specificity of 83 % (95 % CI 68-93 %) for IA and a sensitivity of 77 % (CI 95 % 62-87 %) and specificity 53 % (95 % CI 37-73 %) for candidaemia were found. APACHE II, SOFA score and mortality rate were in the elevated BDG group significantly altered (26 vs. 21, p < 0.003; 15 vs. 13, p < 0.006; 72 vs. 50 %, p < 0.004).

CONCLUSION

1,3-β-D-glucan assay is helpful for early detection of IFD; moreover, elevated BDG levels can be used as a predictor for outcome in immunocompromised critically ill patients as presented in our study.

Surgery for localized pulmonary mycotic infections in patients with hematopoietic disorder

Background

Surgical resection is considered to be the most effective treatment for localized pulmonary mycotic infections. However it is also a particularly challenging procedure because it is associated with considerable mortality and morbidity. Furthermore, hematopoietic disorders usually cause immunosuppression, anemia, and coagulopathy, which are definite risk factors for surgery. The purpose of this study is to evaluate the surgical outcomes of pulmonary mycotic infections in hematopoietic disorder patients.

Methods

Between 2011 and 2013, 23 patients underwent surgical treatment for pulmonary mycotic infections at a single institution. The patients were divided into two groups; Group A (hematopoietic disorder patients, n = 9) and Group B (n = 14). We retrospectively reviewed medical and radiologic data.

Results

The complex type was more frequent in group A (66.6 %) than in group B (35.7 %). Postoperatively, there was no mortality. However, morbidity was 22.2 % (2 incomplete expansion) in group A, and 35.6 % (1 prolonged air leak, 3 bleeding, 1 Bronchopleural fistula) in group B. The difference in morbidity between the groups did not show any statistical significance (p = 0.657) as well as duration of chest tube drainage, and postoperative hospital stay. The hematopoietic disorder patients did not impose a risk factor for morbidity and mortality.

Conclusions

Although hematopoietic disorder patients have many surgical risk factors, the surgical treatment of pulmonary mycotic infections produces very acceptable outcomes in selected cases.

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.

How we treat invasive fungal diseases in patients with acute leukemia: the importance of an individualized approach

Invasive fungal diseases (IFDs) represent an important cause of treatment failure in adults with acute leukemia. Because of leukemia’s heterogeneity, the risk for IFDs is highly variable. We therefore apply a risk-adapted antifungal strategy with strong emphasis on pretreatment and day-15 posttreatment to allow earlier and more individualized interventions. We determine pretreatment risks for IFDs based on 4 factors: (1) host fitness for standard therapy (ie, fit, unfit, or frail); (2) leukemia resistance (high vs low probability of achieving complete remission [CR]); (3) anticipated treatment-related toxicity such as neutropenia, mucositis, and steroid-induced immunosuppression; and (4) patient exposure to opportunistic fungi. Accordingly, we stratify patients as high, intermediate, or low risk for IFDs and apply risk-adapted antifungal strategies, including primary or secondary prophylaxis and diagnostic-based preemptive or empiric therapy. Prevention of IFDs also relies on optimizing organ function, decreasing exposure to opportunistic fungi, and improving net state of immunosuppression with use of better-tolerated and investigational agents for unfit patients and those with adverse leukemia biology. Novel targeted and safe therapies that can achieve higher rates of sustained CR among patients with adverse genetics offer the best promise for reducing the burden of IFDs in these patients.

Use and limits of (1-3)-β-d-glucan assay (Fungitell), compared to galactomannan determination (Platelia Aspergillus), for diagnosis of invasive aspergillosis

This study was undertaken to examine the performance of the Fungitell β-glucan (BG) assay, to compare it with that of the galactomannan (GM) test for the diagnosis of invasive aspergillosis (IA) in patients with hematological malignancies, and to examine the rates of false-positive BG and GM test results due to β-lactam antibiotics among sera of patients with Gram-positive or Gram-negative bacteremia and selected sera with false-positive results from the GM test. Serum samples from 105 patients with proven (n = 14) or probable (n = 91) IA, 97 hematology patients at risk for invasive fungal infections, 50 healthy blood donors, and 60 patients with bacteremia were used to study the sensitivities and specificities of the assays. The GM test was more specific than the BG assay (97% versus 82%, respectively; P = 0.0001) and the BG assay was more sensitive than the GM test (81% versus 49%, respectively; P < 0.0001) for IA diagnosis. The study of 49 separate batches of β-lactam antibiotics showed high and very similar rates of false-positive results for the GM and BG assays (29 and 33%, respectively; P = 0.82) but with an almost complete lack of concordance between the 2 assays. For patients with bacteremia, the rate of false-positive results was much higher with the BG test than with the GM test (37% versus 2%, respectively; P < 0.0001), with no significant difference between Gram-positive and Gram-negative bacteremia. In conclusion, the BG test may be useful for the diagnosis of IA because of its high sensitivity in comparison with the GM test, but the overall benefit of this assay remains limited because of its inadequate specificity and its cost.