[Aspergillus in airway material : Ignore or treat?]

Aspergillus-specific IgG antibodies for diagnosing chronic pulmonary aspergillosis compared to the reference standard

OBJECTIVES

To evaluate the performance of Aspergillus-specific IgG antibodies for diagnosing chronic pulmonary aspergillosis (CPA) by using a cohort of patients with histologically proven CPA as a reference standard.

METHODS

We collected Aspergillus-specific IgG antibody titres from patients with histologically proven CPA in collaboration with CPAnet study sites in Denmark, Germany, Belgium, India, Moldova, and Pakistan (N = 47). Additionally, sera from diseased and healthy controls were prospectively collected at the Medical Clinic of the Research Center, Borstel, Germany (n = 303). Aspergillus-specific IgG antibody titres were measured by the ImmunoCAP® assay (Phadia 100, Thermo Fisher Scientific, Uppsala, Sweden). An Aspergillus-specific IgG antibody titre ≥50 mgA/L was considered positive.

RESULTS

Using patients with histologically proven CPA as the reference standard, the ImmunoCAP® Aspergillus-specific IgG antibody test had a sensitivity and specificity of 85.1% (95% CI: 71.7-93.8%) and 83.6% (95% CI: 78.0-88.3%), respectively. Patients with histologically proven CPA had significantly higher Aspergillus-specific IgG antibody titre with a median of 83.45 mgA/L (interquartile range 38.9-115.5) than all other cohorts (p < 0.001). False-positive test results occurred in one-third of 79 healthy controls.

DISCUSSION

Our study results confirm a high sensitivity of the Aspergillus-specific IgG antibody test for the diagnosis of CPA when using patients with histologically proven CPA as a reference standard. However, positive test results should always match radiological findings as false-positive test results limit the interpretation of the test.

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.

Diagnosis values of IL-6 and IL-8 levels in serum and bronchoalveolar lavage fluid for invasive pulmonary aspergillosis in chronic obstructive pulmonary disease

Among immunologically normal hosts, patients with chronic obstructive pulmonary disease (COPD) are considered to be at high risk of invasive pulmonary aspergillosis (IPA), and early diagnosis and treatment are the key to improving the prognosis of patients. Here we aimed to evaluate whether interleukin (IL)-6 and IL-8 might be used in the detection and diagnosis of IPA in patients with COPD. We prospectively collected 106 patients with COPD and divided them into non-IPA (n=74), probable/possible IPA (n=26) and proven IPA (n=6). Platelia Aspergillus kit was used to detect galactomannan in bronchoalveolar lavage fluid (BALF), and serum and ELISA kit was used to detect IL-6 and IL-8 levels. Diagnostic efficiency of IL-6, IL-8 and galactomannan in serum and BALF was evaluated by receiver operating characteristic curve. Compared with the non-IPA group, the proven/probable IPA group showed significantly elevated levels of IL-6 and IL-8 in both serum and BALF, which were positively correlated with galactomannan levels. The sensitivity and specificity of IL-6 for diagnosing IPA were 74.32% and 81.25% (cut-off at 92.82 pg/mL, area under the curve (AUC)=0.8366) in serum and 68.92% and 71.88% (cut-off at 229.4 pg/mL, AUC=0.7694) in BALF. The sensitivity and specificity of IL-8 for diagnosing IPA were 83.78% and 81.25% (cut-off at 93.46 pg/mL, AUC=0.8756) in serum and 85.14% and 75.00% (cut-off at 325.4 pg/mL, AUC=0.8252) in BALF. The elevated levels of IL-6 and IL-8 in patients with IPA with COPD could be used as auxiliary indicators to diagnose IPA in addition to galactomannan.

Diagnosis of Breakthrough Fungal Infections in the Clinical Mycology Laboratory: An ECMM Consensus Statement

Breakthrough invasive fungal infections (bIFI) cause significant morbidity and mortality. Their diagnosis can be challenging due to reduced sensitivity to conventional culture techniques, serologic tests, and PCR-based assays in patients undergoing antifungal therapy, and their diagnosis can be delayed contributing to poor patient outcomes. In this review, we provide consensus recommendations on behalf of the European Confederation for Medical Mycology (ECMM) for the diagnosis of bIFI caused by invasive yeasts, molds, and endemic mycoses, to guide diagnostic efforts in patients receiving antifungals and support the design of future clinical trials in the field of clinical mycology. The cornerstone of lab-based diagnosis of breakthrough infections for yeast and endemic mycoses remain conventional culture, to accurately identify the causative pathogen and allow for antifungal susceptibility testing. The impact of non-culture-based methods are not well-studied for the definite diagnosis of breakthrough invasive yeast infections. Non-culture-based methods have an important role for the diagnosis of breakthrough invasive mold infections, in particular invasive aspergillosis, and a combination of testing involving conventional culture, antigen-based assays, and PCR-based assays should be considered. Multiple diagnostic modalities, including histopathology, culture, antibody, and/or antigen tests and occasionally PCR-based assays may be required to diagnose breakthrough endemic mycoses. A need exists for diagnostic tests that are effective, simple, cheap, and rapid to enable the diagnosis of bIFI in patients taking antifungals.

Performance of the Bronchoalveolar Lavage Fluid Aspergillus Galactomannan Lateral Flow Assay with Cube Reader for Diagnosis of Invasive Pulmonary Aspergillosis: a Multicenter Cohort Study

BACKGROUND

The Aspergillus Galactomannan Lateral Flow Assay (LFA) is a rapid test for the diagnosis of invasive aspergillosis (IA) that has been almost exclusively evaluated in patients with hematologic malignancies. An automated digital cube reader which allows for quantification of results has recently been added to the test kits.

METHODS

We performed a retrospective multicenter study on bronchoalveolar lavage fluid (BALF) samples obtained from 296 patients with various underlying diseases (65% without underlying hematological malignancy) who had BALF galactomannan (GM) ordered between 2013 and 2019 at the University of California San Diego, the Medical University of Graz, Austria, and the Mannheim University Hospital, Germany.

RESULTS

Cases were classified as proven (n=2), probable (n=56), putative (n=30), possible (n=45), and no IA (n=162). The LFA showed an area under the curve (AUC) of 0.865 (95% CI 0.815-0.916) for differentiating proven/probable or putative IA versus no IA, with a sensitivity of 74% and a specificity of 83% at an optical density index cut-off of 1.5. After exclusion of GM as mycological criterion for case classification, diagnostic performance of the LFA was highly similar to GM testing (AUC 0.892 versus 0.893, respectively). LFA performance was consistent across different patient cohorts and centers.

CONCLUSION

In this multicenter study the LFA assay from BALF demonstrated good diagnostic performance for IA that was consistent across patient cohorts and locations. The LFA may serve a role as a rapid test that may replace conventional GM testing in settings where GM results are not rapidly available.

CPAnet Registry-An International Chronic Pulmonary Aspergillosis Registry

Chronic pulmonary aspergillosis (CPA) is a chronic fungal infection of the lung associated with high morbidity and mortality. The CPA Research network (CPAnet) registry established in 2018 is an international multicenter collaboration aiming to improve CPA knowledge and patient care. This study's aim was to describe the data collection process and content of CPAnet registry with preliminary clinical data. In the CPAnet registry, clinical data are collected through a web-based questionnaire. Data include CPA phenotype, comorbidities, treatment, outcome, and follow-up from several international centers. An exemplary descriptive analysis was performed on 74 patients, who were registered online before April 2020. CPA patients were predominantly (72%) male, 39% had chronic obstructive pulmonary disease, and 68% had a history of smoking. Chronic cavitary pulmonary aspergillosis was the most common CPA subtype (62%). In 32 patients (52%), voriconazole was the preferred first-line therapy. The multicenter multinational CPAnet registry is a valuable approach to gather comprehensive data on a large study population and reflects real-world clinical practice rather than focusing on specific patient populations in more specialized centers. Additional CPA reference centers are being encouraged to join this promising clinical research collaboration.

Point-of-care diagnosis of invasive aspergillosis in non-neutropenic patients: Aspergillus Galactomannan Lateral Flow Assay versus Aspergillus-specific Lateral Flow Device test in bronchoalveolar lavage

BACKGROUND

We compared new Aspergillus Galactomannan Lateral Flow Assay with the newly formatted Aspergillus-specific Lateral Flow device tests for the diagnosis of invasive pulmonary aspergillosis (IPA) in non-neutropenic patients.

METHODS

We performed both tests in 82 bronchoalveolar lavage fluid samples from 82 patients at risk for IPA but without underlying haematologic malignancy. Samples were collected between September 2016 and September 2018 at the University of California San Diego, United States. IPA was classified following two published consensus criteria.

RESULTS

Classification of cases varied widely between the two consensus criteria. When using criteria established for the intensive care unit, 26/82 patients (32%) met criteria for proven or putative IPA. Both point-of-care assays showed sensitivities ranging between 58% and 69%, with specificities between 68% and 75%. Sensitivity increased up to 81% when both tests were combined.

CONCLUSION

The study outlines the need for updated, unified and more broadly applicable consensus definitions for classifying IPA in non-neutropenic patients, a work that is currently in progress. Both point-of-care tests showed comparable performance, with sensitivities and specificities in the 60%-70% range when used alone and increasing to 80% when used in combination. The new point-of-care tests may serve a role at the bedside in those with clinical suspicion of IPA.

Improving the rates of Aspergillus detection: an update on current diagnostic strategies

INTRODUCTION

The spectrum of disease caused by Aspergillus spp. is dependent on the immune system of the host, and ranges from invasive aspergillosis (IA) to chronic pulmonary aspergillosis (CPA). Early and reliable diagnosis of Aspergillus disease is important to decrease associated morbidity and mortality. Areas covered: The following review will give an update on current diagnostic strategies for the diagnosis of IA and CPA. Expert commentary: Several new diagnostics for IA (including point-of-care tests) are now available to complement galactomannan testing. In particular, immunoPET/MRI imaging may be a promising approach for diagnosing IA in the near future. Notably, nearly all new biomarkers and tests for IA have been evaluated in the hematology setting only. Validation of biomarkers and tests is therefore needed for the increasing proportion of patients who develop IA outside the hematology setting. As an important first step, reliable definitions of IA are needed for non-hematology settings as clinical presentation and radiologic findings differ in these settings. CPA diagnosis is based on a combination of radiological findings in chest CT, mycological evidence (e.g. by the Aspergillus-specific IgG assay), exclusion of alternative diagnosis and chronicity. ([18F]FDG) PET/CT and immuno PET/MRI imaging are promising new imaging approaches.

Pulmonary Diseases in Refugees and Migrants in Europe

More than 2 million people fleeing conflict, persecution, and poverty applied for asylum between 2015 and 2016 in the European Union. Due to this, medical practitioners in recipient countries may be facing a broader spectrum of conditions and unusual presentations not previously encountered, including a wide range of infections with pulmonary involvement. Tuberculosis is known to be more common in migrants and has been covered broadly in other publications. The scope of this review was to provide an overview of exotic infections with pulmonary involvement that could be encountered in refugees and migrants and to briefly describe their epidemiology, diagnosis, and management. As refugees and migrants travel from numerous countries and continents, it is important to be aware of the various organisms that might cause disease according to the country of origin. Some of these diseases are very rare and geographically restricted to certain regions, while others have a more cosmopolitan distribution. Also, the spectrum of severity of these infections can vary from very benign to severe and even life-threatening. We will also describe infectious and noninfectious complications that can be associated with HIV infection as some migrants might originate from high HIV prevalence countries in sub-Saharan Africa. As the diagnosis and treatment of these diseases can be challenging in certain situations, patients with suspected infection might require referral to specialized centers with experience in their management. Additionally, a brief description of noncommunicable pulmonary diseases will be provided.