Defining Galactomannan Positivity in the Updated EORTC/MSGERC Consensus Definitions of Invasive Fungal Diseases

Performance of the galactomannan test for the diagnosis of invasive pulmonary aspergillosis using non-invasive proximal airway samples

OBJECTIVE

To diagnose invasive pulmonary aspergillosis (IPA), galactomannan (GM) detection in serum or bronchoalveolar lavage fluid (BALF) is widely used. However, the utility of proximal airway GM test (from induced sputum or tracheal aspirate) has not been well elucidated.

METHODS

In this retrospective cohort study, we evaluated the diagnostic performance of proximal airway GM in diagnosis of IPA including COVID-19 associated pulmonary aspergillosis (CAPA). Between January 2022 and January 2023, patients who had been tested for GM with clinical suspicion or for surveillance from any specimen (serum, induced sputum, tracheal aspirate, and BALF) were screened. IPA was diagnosed using EORTC/MSGERC criteria, and CAPA was diagnosed following the 2020 ECMM/ISHAM consensus criteria.

RESULTS

Of 624 patients with GM results, 70 met the criteria for proven/probable IPA and 427 had no IPA. The others included possible IPA and chronic form of aspergillosis. The sensitivities and specificities of serum, proximal airway, and BALF GM for proven/probable IPA versus no IPA were 78.9% and 70.6%, 93.1% and 78.7%, and 78.6% and 91.0%, respectively. Areas under the receiver operating characteristic curve (AUCs) were 0.742 for serum GM, 0.935 for proximal airway GM, and 0.849 for BALF GM (serum GM vs proximal airway GM, p = 0.014; proximal airway GM vs BALF GM, p = 0.334; serum GM vs BALF GM, p = 0.286).

CONCLUSION

This study demonstrates that the performance of GM test from non-invasive proximal airway samples is comparable or even better than those from serum and distal airway sample (BALF).

Exploring European Consensus About the Remaining Treatment Challenges and Subsequent Opportunities to Improve the Management of Invasive Fungal Infection (IFI) in the Intensive Care Unit

BACKGROUND

The global prevalence of invasive fungal infections (IFI) is increasing, particularly within Intensive Care Units (ICU), where Candida spp. and Aspergillus spp. represent the most important pathogens. Diagnosis and management of IFIs becomes progressively challenging, with increasing antifungal resistance and the emergence of rare fungal species. Through a consensus survey focused on assessing current views on how IFI should be managed, the aim of this project was to identify challenges around diagnosing and managing IFIs in the ICU. The current status in different countries and perceived challenges to date amongst a multidisciplinary cohort of healthcare professionals involved in the care of IFI in the ICU was assessed.

METHODS

Using a modified Delphi approach, an expert panel developed 44 Likert-scale statements across 6 key domains concerning patient screening and minimal standards for diagnosis of IFIs in ICU; initiation and termination of antifungal treatments and how to minimise their side effects and insights for future research on this topic. These were used to develop an online survey which was distributed on a convenience sampling basis utilising the subscriber list held by an independent provider (M3 Global). This survey was distributed to intensivists, infectious disease specialists, microbiologists and antimicrobial/ICU pharmacists within the UK, Germany, Spain, France and Italy. The threshold for consensus was set at 75%.

RESULTS

A total of 335 responses were received during the five-month collection period. From these, 29/44 (66%) statements attained very high agreement (≥ 90%), 11/44 (25%) high agreement (< 90% and ≥ 75%), and 4/44 (9%) did not meet threshold for consensus (< 75%).

CONCLUSION

The results outline the need for physicians to be aware of the local incidence of IFI and the associated rate of azole resistance in their ICUs. Where high clinical suspicion exists, treatment should start immediately and prior to receiving the results from any diagnostic test. Beta-D-glucan testing should be available to all ICU centres, with results available within 48 h to inform the cessation of empirical antifungal therapy. These consensus statements and proposed measures may guide future areas for further research to optimise the management of IFIs in the ICU.

Serial Bronchoalveolar Lavage Fluid Aspergillus Galactomannan and Treatment Response in Invasive Pulmonary Aspergillosis

We studied patients diagnosed with aspergillosis based on positive bronchoalveolar lavage (BAL) Aspergillus galactomannan (GM) who had follow-up BAL sampling within 180 days. GM trend and clinical outcome were concordant in only 60% (30/50). While useful for the initial diagnosis, BAL GM trending does not always correlate with treatment response.

Point-of-care testing for viral-associated pulmonary aspergillosis

INTRODUCTION

Over the last years, severe respiratory viral infections, particularly those caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the influenza virus, have emerged as risk factor for viral-associated pulmonary aspergillosis (VAPA) among critically ill patients. Delays in diagnosis of VAPA are associated with increased mortality. Point-of-care-tests may play an important role in earlier diagnosis of VAPA and thus improve patient outcomes.

AREAS COVERED

The following review will give an update on point-of-care tests for VAPA, analyzing performances in respiratory and blood specimens.

EXPERT OPINION

Point-of-care tests have emerged, and particularly the IMMY Aspergillus galactomannan lateral flow assay (LFA) shows performances comparable to the galactomannan ELISA for diagnosis of VAPA. Notably, nearly all evaluations of POC tests for VAPA have been performed in COVID-19 patients, with very limited data in influenza patients. For early diagnosis of COVID associated pulmonary aspergillosis (CAPA), the LFA has shown promising performances in respiratory samples, particularly in bronchoalveolar lavage fluid, and may thereby help in improving patient outcomes. In contrast, serum LFA testing may not be useful for early diagnosis of disease, except in cases with invasive tracheobronchial aspergillosis.

An observational cohort study of bronchoalveolar lavage fluid galactomannan and Aspergillus culture positivity in patients requiring mechanical ventilation

Rationale

Critically ill patients who develop invasive pulmonary aspergillosis (IPA) have high mortality rates despite antifungal therapy. Diagnosis is difficult in these patients. Bronchoalveolar lavage (BAL) fluid galactomannan (GM) is a helpful marker of infection, although the optimal cutoff for IPA is unclear. We aimed to evaluate the BAL fluid GM and fungal culture results, demographics, and outcomes among a large cohort of mechanically ventilated patients with suspected pneumonia.

Methods

A single-center cohort study of patients enrolled in the Successful Clinical Response in Pneumonia Therapy (SCRIPT) study from June 2018 to March 2023. Demographics, BAL results, and outcomes data were extracted from the electronic health record and compared between groups of patients who grew Aspergillus on a BAL fluid culture, those who had elevated BAL fluid GM levels (defined as >0.5 or >0.8) but did not grow Aspergillus on BAL fluid culture, and those with neither.

Results

Of over 1700 BAL samples from 688 patients, only 18 BAL samples grew Aspergillus. Patients who had a BAL sample grow Aspergillus (n=15) were older (median 71 vs 62 years, p=0.023), had more days intubated (29 vs 11, p=0.002), and more ICU days (34 vs 15, p=0.002) than patients whose BAL fluid culture was negative for Aspergillus (n=672). The BAL fluid galactomannan level was higher from samples that grew Aspergillus on culture than those that did not (median ODI 7.08 vs 0.11, p<0.001), though the elevation of BAL fluid GM varied across BAL samples for patients who had serial sampling. Patients who grew Aspergillus had a similar proportion of underlying immunocompromise compared with the patients who did not, and while no statistically significant difference in overall unfavorable outcome, had longer duration of ventilation and longer ICU stays.

Conclusions

In this large cohort of critically ill patients with a high number of BAL samples with GM levels, we found a relatively low rate of Aspergillus growth. Patients who eventually grew Aspergillus had inconsistently elevated BAL fluid GM, and many patients with elevated BAL fluid GM did not grow Aspergillus. These data suggest that the pre-test probability of invasive pulmonary aspergillosis should be considered low in a general ICU population undergoing BAL evaluation to define the etiology of pneumonia. Improved scoring systems are needed to enhance pre-test probability for diagnostic test stewardship purposes.

Acute Invasive Pulmonary Aspergillosis: Clinical Presentation and Treatment

Among all clinical manifestations of pulmonary aspergillosis, invasive pulmonary aspergillosis (IPA) is the most acute presentation. IPA is caused by Aspergillus hyphae invading the pulmonary tissue, causing either tracheobronchitis and/or bronchopneumonia. The degree of fungal invasion into the respiratory tissue can be seen as a spectrum, going from colonization to deep tissue penetration with angio-invasion, and largely depends on the host's immune status. Patients with prolonged, severe neutropenia and patients with graft-versus-host disease are at particularly high risk. However, IPA also occurs in other groups of immunocompromised and nonimmunocompromised patients, like solid organ transplant recipients or critically ill patients with severe viral disease. While a diagnosis of proven IPA is challenging and often warranted by safety and feasibility, physicians must rely on a combination of clinical, radiological, and mycological features to assess the likelihood for the presence of IPA. Triazoles are the first-choice regimen, and the choice of the drug should be made on an individual basis. Adjunctive therapy such as immunomodulatory treatment should also be taken into account. Despite an improving and evolving diagnostic and therapeutic armamentarium, the burden and mortality of IPA still remains high. This review aims to give a comprehensive and didactic overview of the current knowledge and best practices regarding the epidemiology, clinical presentation, diagnosis, and treatment of acute IPA.

Microbiological Diagnosis of Pulmonary Aspergillus Infections

As microbiological tests play an important role in our diagnostic algorithms and clinical approach towards patients at-risk for pulmonary aspergillosis, a good knowledge of the diagnostic possibilities and especially their limitations is extremely important. In this review, we aim to reflect critically on the available microbiological diagnostic modalities for diagnosis of pulmonary aspergillosis and formulate some future prospects. Timely start of adequate antifungal treatment leads to a better patient outcome, but overuse of antifungals should be avoided. Current diagnostic possibilities are expanding, and are mainly driven by enzyme immunoassays and lateral flow device tests for the detection of Aspergillus antigens. Most of these tests are directed towards similar antigens, but new antibodies towards different targets are under development. For chronic forms of pulmonary aspergillosis, anti-Aspergillus IgG antibodies and precipitins remain the cornerstone. More studies on the possibilities and limitations of molecular testing including targeting resistance markers are ongoing. Also, metagenomic next-generation sequencing is expanding our future possibilities. It remains important to combine different test results and interpret them in the appropriate clinical context to improve performance. Test performances may differ according to the patient population and test results may be influenced by timing, the tested matrix, and prophylactic and empiric antifungal therapy. Despite the increasing armamentarium, a simple blood or urine test for the diagnosis of aspergillosis in all patient populations at-risk is still lacking. Research on diagnostic tools is broadening from a pathogen focus on biomarkers related to the patient and its immune system.

Drug-induced interstitial lung disease: a narrative review of a clinical conundrum

INTRODUCTION

Drug-induced interstitial lung disease (DI-ILD) is increasing in incidence, due to the use of many new drugs across a broad range of cancers and chronic inflammatory diseases. The presentation and onset of DI-ILD are variable even for the same drug across different individuals. Clinical suspicion is essential for identifying these conditions, with timely drug cessation an important determinant of outcomes.

AREAS COVERED

This review provides a comprehensive and up-to-date summary of epidemiology, risk factors, pathogenesis, diagnosis, treatment, and prognosis of DI-ILD. Relevant research articles from PubMed and Medline searches up to September 2023 were screened and summarized. Specific drugs including immune checkpoint inhibitors, CAR-T cell therapy, methotrexate, and amiodarone are discussed in detail. The potential role of pharmacogenomic profiling for lung toxicity risk is considered.

EXPERT OPINION

DI-ILD is likely to be an increasingly important contributor to respiratory disability in the community. These conditions can negatively impact quality of life and patient longevity, due to associated respiratory compromise as well as cessation of evidence-based therapy for the underlying disease. This clinical conundrum is relevant to all areas of medicine, necessitating increased understanding and greater vigilance for drug-related lung toxicity.

Recent Advances in Biomedical Applications of Mannans and Xylans

Plant-based phytochemicals, including flavonoids, alkaloids, tannins, saponins, and other metabolites, have attracted considerable attention due to their central role in synthesizing nanomaterials with various biomedical applications. Hemicelluloses are the second most abundant among naturally occurring heteropolymers, accounting for one-third of all plant constituents. In particular, xylans, mannans, and arabinoxylans are structured polysaccharides derived from hemicellulose. Mannans and xylans are characterized by their linear configuration of β-1,4-linked mannose and xylose units, respectively. At the same time, arabinoxylan is a copolymer of arabinose and xylose found predominantly in secondary cell walls of seeds, dicotyledons, grasses, and cereal tissues. Their widespread use in tissue engineering, drug delivery, and gene delivery is based on their properties, such as cell adhesiveness, cost-effectiveness, high biocompatibility, biodegradability, and low immunogenicity. Moreover, it can be easily functionalized, which expands their potential applications and provides them with structural diversity. This review comprehensively addresses recent advances in the field of biomedical applications. It explores the potential prospects for exploiting the capabilities of mannans and xylans in drug delivery, gene delivery, and tissue engineering.

Effect of volume of instillate on the diagnostic utility of bronchoalveolar lavage galactomannan in patients with suspected chronic pulmonary aspergillosis-A pilot study

BACKGROUND

Bronchoalveolar lavage (BAL) galactomannan (GM) is commonly used to diagnose Aspergillus-related lung diseases. However, unlike serum GM, which is measured in undiluted blood, BAL-GM is estimated using variable aliquots and cumulative volume of instillates during bronchoscopy.

OBJECTIVE

Since different studies have reported varying diagnostic accuracy and cut-offs for BAL-GM in CPA, we hypothesized that the total volume of instillate and 'order/label' of aliquots significantly affects the BAL-GM values, which was evaluated as part of this study.

PATIENTS & METHODS

We obtained 250 BAL samples from 50 patients (five from each) with suspected chronic pulmonary aspergillosis. BAL fluid was collected after instilling sequential volumes of 40 mL of normal saline each for the first four labels and a fifth label was prepared by mixing 1 mL from each of the previous labels. The GM level of each label was measured by PLATELIA™ ASPERGILLUS Ag enzyme immunoassay. This study measured the discordance, level of agreement, diagnostic characteristics (sensitivity, specificity and AUROC) and best cut-offs for BAL-GM in the different aliquots of lavage fluid.

RESULTS

The study population, classified into CPA (28%) and non-CPA (72%) groups, based on ERS/ESCMID criteria (excluding BAL-GM) were not different with respect to clinico-radiological characteristics. The discordance of BAL-GM positivity (using a cut-off of >1) between the serial labels for the same patient ranged between 10% and 22%, while the discordance between classification using BAL-GM positivity (using a cut-off of ≥1) and clinic-radio-microbiological classification ranged between 18% and 30%. The level of agreement for serial labels was at best fair (<0.6 for all except one 'label'). The AUROC for the serial samples ranged between 0.595 and 0.702, with the '40 mL and the 'mix' samples performing the best. The best BAL-GM cut-off also showed significant variation between serial labels of varying dilutions (Range:1.01 - 4.26).

INTERPRETATION

This study highlights the variation in BAL-GM measured and the 'positivity' between different 'labels' of aliquots of BAL, with the first aliquot and the mixed sample showing the best performances for diagnosis of CPA. Future studies should attempt to 'standardise' the instilled volume for BAL-GM estimation to standardise the diagnostic yield.

Diagnostic Utility of Galactomannan Enzyme Immunoassay in Invasive Aspergillosis in Pediatric patients with Hematological Malignancy

OBJECTIVE

This study aims to determine the diagnostic utility of galactomannan enzyme immunoassay (GM EIA) in invasive aspergillosis (IA) in children with hematological malignancy (high risk population) in terms of sensitivity, specificity, negative predictive value (NPV) and positive predictive values (PPV) at various cut offs while validating the revised EORTC/MSG 2019 criteria in order to obtain the best cut-off.

MATERIAL AND METHODS

For 100 pediatric patients, serum and respiratory samples were collected. Clinical, mycological workup (potassium-hydroxide mount, fungal culture) and GM EIA was done to classify proven, probable, and possible IA as per EORTC-MSG guidelines,2019. Sensitivity, specificity, PPV and NPV were calculated of GM indices at cut-off 0.5, 0.7 and 1, and validated with revised EORTC -MSG, 2019.

RESULTS

Of 100 patients enrolled, 75 were diagnosed with ALL, 14 with AML, two with Hodgkin's, three had non-Hodgkin lymphoma, and six had undifferentiated leukemia. With routine mycological findings, 51 were classified as probable IA, 11 as possible IA, and 38 as no IA. Aspergillus flavus was the most prevalent on culture (56.9%, 29/51) followed by A. fumigatus (29%, 15/51) A. niger (7.8%, 4/51), A. terreus (3.9%, 2/51) and A. nidulans (2%, 1/51). GM EIA demonstrated sensitivity 82.3%, specificity 97.4%, PPV 98.1%, and NPV 77.1% at cut-off 0.67 when comparing probable/possible IA v/s no IA groups. The GM EIA had the best sensitivity (82.4%), specificity (81.8%), PPV (95.5%), and NPV (50%) at cut off 0.78 when the probable IA group was compared to the possible IA. Seven patients succumbed of whom 5 had GMI ≥ 2.

CONCLUSION

This study deduces the optimal cut-off for serum GM EIA to be 0.67 obtained by ROC analysis when comparing possible and probable IA versus no IA and reinforces the definition of probable category of EORTC-MSG criteria, 2019. At 0.5 ODI the sensitivity (87.1%) and NPV (80.5%) are high, thus making it the most suitable cut-off for detecting true positive and ruling out IA respectively, in pediatric patients with hematological malignancy. GM EIA when performed adjunctive to clinico-radiological findings can prove to be screening, diagnostic and prognostic test for IA in pediatric hematological malignancy patients.

Characteristics and outcomes for pulmonary aspergillosis in critically ill patients without influenza: A 3-year retrospective study

BACKGROUND

Previous studies have revealed higher mortality rates in patients of severe influenza coinfected with invasive pulmonary aspergillosis (IPA) than in those without the coinfection; nonetheless, the clinical outcome of IPA in critically ill patients without influenza remains unclear.

PATIENTS AND METHODS

This retrospective study was conducted in three institutes. From 2016-2018, all adult patients diagnosed with IPA in the intensive care units (ICUs) were identified. The logistic regression was used to identify the potential risk factors associated with in-hospital mortality in patients with non-influenza IPA. The stratified analysis of IPA patients with and without antifungal therapy was also performed. The final model was established using a forward approach, selecting variables with p-values less than 0.05.

RESULTS

Ninety patients were included during the study period, and 63 (70%) were men. The most common comorbidity was diabetes mellitus (n = 24, 27%), followed by solid cancers (n = 22, 24%). Antifungal therapy was administered to 50 (56%) patients, mostly voriconazole (n = 44). The in-hospital mortality rate was 49% (n = 44). Univariate analysis revealed that the risk factors for mortality included daily steroid dose, APACHE II score, SOFA score, C-reactive protein (CRP) level, carbapenem use, antifungal therapy, and caspofungin use. Multiple regression analysis identified four independent risk factors for mortality: age (Odds ratio [OR], 1.052, p = 0.013), daily steroid dose (OR, 1.057, p = 0.002), APACHE II score (OR, 1.094, p = 0.012), and CRP level (OR, 1.007, p = 0.008). Furthermore, the multivariable analysis identified that more physicians would initiate antifungal therapy for patients with prolonged steroid use (p = 0.001), lower white blood cell count (p = 0.021), and higher SOFA score (p = 0.048). Thus, under the selection bias, the independent risk factors for mortality in the antifungal treatment subgroup were daily steroid dose (OR, 1.046, p = 0.001) and CRP (OR, 1.006, p = 0.018), whereas the independent risk factor for mortality in the untreated group became APACHE II score (OR, 1.232, p = 0.007).

CONCLUSIONS

Patients with IPA had a substantially high mortality. Overall, age, steroid use, APACHE II score, and CRP level were identified as the independent risk factors for mortality in patients in the ICU.

Superior Accuracy of Aspergillus Plasma Cell-Free DNA Polymerase Chain Reaction Over Serum Galactomannan for the Diagnosis of Invasive Aspergillosis

BACKGROUND

Invasive aspergillosis (IA) in immunocompromised hosts carries high morbidity and mortality. Diagnosis is often delayed because definitive diagnosis requires invasive specimen collection, while noninvasive testing with galactomannan is moderately accurate. Plasma cell-free DNA polymerase chain reaction (cfDNA PCR) represents a novel testing modality for the noninvasive diagnosis of invasive fungal disease (IFD). We directly compared the performance of Aspergillus plasma cfDNA PCR with serum galactomannan for the diagnosis of IA during routine clinical practice.

METHODS

We conducted a retrospective study of all patients with suspected IFD who had Aspergillus plasma cfDNA PCR testing at Stanford Health Care from 1 September 2020 to 30 October 2022. Patients were categorized into proven, probable, possible, and no IA based on the EORTC/MSG definitions. Primary outcomes included the clinical sensitivity and specificity for Aspergillus plasma cfDNA PCR and galactomannan.

RESULTS

Overall, 238 unique patients with Aspergillus plasma cfDNA PCR test results, including 63 positives and 175 nonconsecutive negatives, were included in this study. The majority were immunosuppressed (89.9%) with 22.3% 30-day all-cause mortality. The overall sensitivity and specificity of Aspergillus plasma cfDNA PCR were 86.0% (37 of 43; 95% confidence interval [CI], 72.7-95.7) and 93.1% (121 of 130; 95% CI, 87.4-96.3), respectively. The sensitivity and specificity of serum galactomannan in hematologic malignancies/stem cell transplants were 67.9% (19 of 28; 95% CI, 49.3-82.1) and 89.8% (53 of 59; 95% CI, 79.5-95.3), respectively. The sensitivity of cfDNA PCR was 93.0% (40 of 43; 95% CI, 80.9-98.5) in patients with a new diagnosis of IA.

CONCLUSIONS

Aspergillus plasma cfDNA PCR represents a more sensitive alternative to serum galactomannan for noninvasive diagnosis of IA.

Challenges in management of invasive fungal infections in stem cell transplant

Invasive fungal infections cause significant morbidity and mortality in hematopoietic stem cell transplant recipients. In order to minimize these infections, prophylaxis has become routine, although the agents used have changed over time. This presents new challenges as we consider an approach to breakthrough infections and recognize the epidemiologic shift toward isolates with higher rates of drug resistance. This review outlines the management of the most common pathogens (Candida, Aspergillus, Mucorales) as well as rarer pathogens that have higher rates of resistance (Trichosporon, Fusarium, Scedosporium, and Lomentospora). We discuss potential approaches to proven or possible breakthrough infections with yeast and pulmonary mold disease. Finally, we outline the role for combination therapy and newer antifungals, acknowledging current knowledge gaps and areas for future exploration.

Outbreaks of Fungal Infections in Hospitals: Epidemiology, Detection, and Management

Nosocomial clusters of fungal infections, whilst uncommon, cannot be predicted and are associated with significant morbidity and mortality. Here, we review reports of nosocomial outbreaks of invasive fungal disease to glean insight into their epidemiology, risks for infection, methods employed in outbreak detection including genomic testing to confirm the outbreak, and approaches to clinical and infection control management. Both yeasts and filamentous fungi cause outbreaks, with each having general and specific risks. The early detection and confirmation of the outbreak are essential for diagnosis, treatment of affected patients, and termination of the outbreak. Environmental sampling, including the air in mould outbreaks, for the pathogen may be indicated. The genetic analysis of epidemiologically linked isolates is strongly recommended through a sufficiently discriminatory approach such as whole genome sequencing or a method that is acceptably discriminatory for that pathogen. An analysis of both linked isolates and epidemiologically unrelated strains is required to enable genetic similarity comparisons. The management of the outbreak encompasses input from a multi-disciplinary team with epidemiological investigation and infection control measures, including screening for additional cases, patient cohorting, and strict hygiene and cleaning procedures. Automated methods for fungal infection surveillance would greatly aid earlier outbreak detection and should be a focus of research.

Culture-independent diagnostic approaches for invasive aspergillosis in solid organ transplant recipients

Prompt and accurate diagnosis of invasive aspergillosis (IA) is crucial for immunocompromised patients, including those who have received a solid organ transplant (SOT). Despite their low sensitivity, microscopic detection and conventional culture are considered the 'gold standard' methods. In conjunction with conventional culture, culture-independent assays such as serum galactomannan testing and Aspergillus polymerase chain reaction (PCR) have been incorporated into the diagnostic process for IA. The recently revised consensus definitions from the European Organization for Research and Treatment of Cancer and the Mycosis Study Group have adjusted the threshold for positive galactomannan testing based on the sample type, and have excluded 1,3-β-D-glucan testing as a mycological criterion. Following extensive standardization efforts, positive Aspergillus PCR tests using serum, plasma, or bronchoalveolar lavage fluid have been added. However, there are limited studies evaluating the clinical utility of these culture-independent assays for the early diagnosis of IA in SOT recipients. Therefore, further research is required to determine whether these assays could aid in the early diagnosis of IA in SOT recipients, particularly in relation to the organ transplanted. In this review, we examine the culture-independent diagnostic methods for IA in SOT recipients, as well as the clinical utility of these assays.

Navigating the challenges of invasive pulmonary aspergillosis in lung cancer treatment: a propensity score study

Background

Invasive pulmonary aspergillosis (IPA) can negatively impact cancer patients' survival. It remains uncertain whether IPA's impact on patient outcomes varies by treatment approach in advanced lung cancer.

Objectives

To explore the association between IPA and outcomes in patients with advanced lung cancer receiving different treatments.

Design

A retrospective cohort study.

Methods

We enrolled patients with advanced-stage lung cancer between 2013 and 2021 at a college hospital in Taiwan and used the 2021 European Organization for Research and Treatment of Cancer/Mycoses Study Group Education and Research Consortium consensus for IPA diagnosis. Multivariable logistic regression was used to identify the IPA risk factors. We compared overall survival (OS) and postgalactomannan (GM) test survival between the IPA and control groups using multivariable Cox proportional hazards regression and the Kaplan-Meier method with propensity score matching (PSM).

Results

Among 2543 patients with advanced-stage lung cancer, 290 underwent a GM test, of which 34 (11.7%) were diagnosed with IPA. Patients undergoing chemotherapy (HR = 4.02, p = 0.027) and immunotherapy [hazard ratio (HR) = 3.41, p = 0.076] tended to have IPA. Compared to the control group, the IPA group had shorter median OS (14.4 versus 9.9 months, p = 0.030) and post-GM test survival (4.5 versus 1.9 months, p = 0.003). IPA was associated with shorter OS (log-rank p = 0.014 and 0.018 before and after PSM, respectively) and shorter 1-year and 2-year survival post-GM test (HR = 1.65 and 1.66, respectively). Patients receiving chemotherapy or immunotherapy had a shorter post-GM test survival if they had IPA.

Conclusions

IPA tended to be diagnosed more frequently in patients receiving chemotherapy or immune checkpoint inhibitors. Patients diagnosed with IPA are associated with shorter survival. Larger cohort studies are needed to verify the observations.

Systematic review and meta-analysis of galactomannan antigen testing in serum and bronchoalveolar lavage for the diagnosis of chronic pulmonary aspergillosis: defining a cutoff

BACKGROUND

A clear cutoff value of galactomannan (GM) has not been established for chronic pulmonary aspergillosis (CPA) and is frequently extrapolated from invasive pulmonary aspergillosis. We performed a systematic review and meta-analysis to evaluate the diagnostic performance of serum and bronchoalveolar lavage (BAL) GM, and to propose a cutoff.

METHODS

We extracted from the studies the cutoff of serum or/and BAL GM associated with true positives, false positives, true negatives, and false negatives. We performed a multi-cutoff model and a non-parametric random effect model. We estimated the optimal cutoff and the area under the curve (AUC) for GM in serum and BAL samples.

RESULTS

Nine studies from 1999 to 2021 were included. Overall, the optimal cutoff of serum GM was 0.96 with a sensitivity of 0.29 (95%CI: 0.14-0.51); specificity of 0.88 (95%CI: 0.73-0.95); and AUC of 0.529 (with a CI: [0.415-0.682] [0.307-0.713]). The AUC for the non-parametric ROC model was 0.631. For BAL GM the cutoff was 0.67 with a sensitivity of 0.68 (95%CI: 0.51-0.82), specificity of 0.84 (95%CI: 0.70-0.92), and AUC of 0.814 (with a CI: [0.696-0.895] [0.733-0.881]). The AUC for the non-parametric model was 0.789.

CONCLUSION

The diagnosis of CPA requires the assessment of a combination of mycological and serological factors, as no single serum and/or BAL GM antigen test is adequate. BAL GM performed better than serum, with better sensitivity and excellent accuracy.

Microbiological Non-Culture-Based Methods for Diagnosing Invasive Pulmonary Aspergillosis in ICU Patients

The diagnosis of invasive pulmonary aspergillosis (IPA) in intensive care unit (ICU) patients is crucial since most clinical signs are not specific to invasive fungal infections. To detect an IPA, different criteria should be considered. Next to host factors and radiological signs, microbiological criteria should be fulfilled. For microbiological diagnostics, different methods are available. Next to the conventional culture-based approaches like staining and culture, non-culture-based methods can increase sensitivity and improve time-to-result. Besides fungal biomarkers, like galactomannan and (1→3)-β-D-glucan as nonspecific tools, molecular-based methods can also offer detection of resistance determinants. The detection of novel biomarkers or targets is promising. In this review, we evaluate and discuss the value of non-culture-based microbiological methods (galactomannan, (1→3)-β-D-glucan, Aspergillus PCR, new biomarker/targets) for diagnosing IPA in ICU patients.

Impact of Invasive Pulmonary Aspergillosis in Critically Ill Surgical Patients with or without Solid Organ Transplantation

BACKGROUND

Critically ill patients, especially those who have undergone solid organ transplantation (SOT), are at risk of invasive pulmonary aspergillosis (IPA). The outcome relevance of adequately treated putative IPA (pIPA) is a matter of debate. The aim of this study is to assess the outcome relevance of pIPA in a cohort of critically ill patients with and without SOT.

METHODS

Data from 121 surgical critically ill patients with pIPA (n = 30) or non-pIPA (n = 91) were included. Cox regression analysis was used to identify risk factors for mortality and unfavourable outcomes after 28 and 90 days.

RESULTS

Mortality rates at 28 days were similar across the whole cohort of patients (pIPA: 31% vs. non-pIPA: 27%) and did not differ in the subgroup of patients after SOT (pIPA: 17% vs. non-pIPA: 22%). A higher Sequential Organ Failure Assessment (SOFA) score and evidence of bacteraemia were identified as risk factors for mortality and unfavourable outcome, whereas pIPA itself was not identified as an independent predictor for poor outcomes.

CONCLUSIONS

Adequately treated pIPA did not increase the risk of death or an unfavourable outcome in this mixed cohort of critically ill patients with or without SOT, whereas higher disease severity and bacteraemia negatively affected the outcome.

Approach to the diagnosis of invasive fungal infections of the respiratory tract in the immunocompromised host

PURPOSE OF REVIEW

The burden of invasive fungal infection is increasing worldwide, largely due to a growing population at-risk. Most serious human fungal pathogens enter the host via the respiratory tract. Early identification and treatment of invasive fungal respiratory infections (IFRIs) in the immunocompromised host saves lives. However, their accurate diagnosis is a difficult challenge for clinicians and mortality remains high.

RECENT FINDINGS

This article reviews IFRIs, focussing on host susceptibility factors, clinical presentation, and mycological diagnosis. Several new diagnostic tools are coming of age including molecular diagnostics and point-of-care antigen tests. As diagnosis of IFRI relies heavily on invasive procedures like bronchoalveolar lavage and lung biopsy, several novel noninvasive diagnostic techniques are in development, such as metagenomics, 'volatilomics' and advanced imaging technologies.

SUMMARY

Where IFRI cannot be proven, clinicians must employ a 'weights-of-evidence' approach to evaluate host factors, clinical and mycological data. Implementation studies are needed to understand how new diagnostic tools can be best applied within clinical pathways. Differentiating invasive infection from colonization and identifying antifungal resistance remain key challenges. As our diagnostic arsenal expands, centralized clinical mycology laboratories and efforts to ensure access to new diagnostics in low-resource settings will become increasingly important.

Clinical characteristics and risk factors of in-hospital mortality in patients coinfected with Pneumocystis jirovecii and Aspergillus

OBJECTIVE

To analyze clinical characteristics and risk factors for in-hospital mortality in patients coinfected with P. jirovecii and Aspergillus.

METHODS

This study included 53 patients with coinfection of P. jirovecii pneumonia (PJP) and invasive pulmonary aspergillosis (IPA) in our center from January 2011 to December 2021. All cases were divided into survivor (n=27) and non-survivor groups (n=26). Medical records, laboratory and radiology data were collected. Risk factors for in-hospital mortality were identified by multivariable analyses.

RESULTS

HIV-positive patients accounted for 3.8%. Fever (77.4%), dyspnea (69.8%) and wet cough (24.5%) were common symptoms. Ground-glass opacity (83.0%), consolidation (71.7%), septal thickening (66.0%), and nodules (54.7%) were the most common radiological signs. CD4+ T cell count and serum albumin (ALB) level were significantly lower in non-survival group than in the survival group. Conversely, serum lactate dehydrogenase (LDH) and procalcitonin (PCT) levels were higher in non-survival group than in survival group. Lactic acidosis [odds ratio (OR): 33.999,95% confidential interval (CI): 3.112-371.409; p=0.004], low CD4+ T cell count (<114 cell/µL) [OR: 19.343, 95% CI: 1.533-259.380; p=0.022] and high level of LDH (> 519 U/L) [OR: 11.422, 95% CI: 1.271-102.669; p=0.030] were independent risk factors for mortality.

CONCLUSION

PJP coinfected with IPA incurs high mortality with nonspecific clinical characteristics and is more likely to involve HIV-negative patients. Lactic acidosis, low CD4+ T cell count and high LDH level are independent risk factors for mortality, close monitoring of these parameters is necessary to help distinguish high-risk patients and make appropriate clinical decisions.

Invasive Cerebral Aspergillosis in Non-Neutropenic Patients: A Case Series from Western India

PURPOSE

Invasive cerebral aspergillosis (ICA) is a rare but fatal infection affecting neutropenic immunocompromised patients. Recently cases have been reported in non-neutropenic settings also. We hereby present a series of ICA cases in non-neutropenic patients diagnosed at our tertiary care centre in Western India between March to October 2021.

METHODS

All patients with clinico-radiological suspicion of CNS infections were analysed. Data regarding Clinico-radiological features, diagnosis, treatment and outcome were collected. After ruling out bacterial, viral and mycobacterial causes, appropriate samples were sent for KOH (potassium hydroxide) wet mount, fungal culture, histopathology and serum/CSF galactomannan.

RESULTS

A total of four patients were diagnosed with ICA with a mean age of 43.5 years. Three patients had significant comorbidities; Diabetes mellitus, chronic liver disease and COVID-19 pneumonia treated with dexamethasone, respectively. One patient had no known predisposing factor. Radiologically, one patient presented with a frontal brain abscess and two patients had multiple subcortical hyperintensities. Three patients were diagnosed based on CSF galactomannan (Platelia™ Aspergillus antigen, Bio-Rad, France) with OD >1 and one patient had high serum galactomannan (OD >2). CSF culture grew Aspergillus species in two patients. All patients were treated with Voriconazole. One patient recovered, and the remaining three succumbed due to delayed presentation and extensive cerebral involvement.

CONCLUSION

Even in non-neutropenic patients, a high index of suspicion is warranted for cerebral aspergillosis. CSF galactomannan can be considered a reliable marker for diagnosing ICA in non-neutropenic settings. Early diagnosis allows timely antifungal therapy, which could be a key to improving the outcomes.

Imaging of Invasive Fungal Infections- The Role of PET/CT

Over the last decades, the population at risk for invasive fungal disease (IFD) has increased because of medical therapy advances and diseases compromising patients' immune systems. The high morbidity and mortality associated with invasive fungal disease in the immunocompromised present the challenge of early diagnosis of the IFD and the need to closely monitor the infection during treatment. The definitive diagnosis of invasive fungal disease based on culture or histopathological methods often has reduced diagnostic accuracy in the immunocompromised and may be very invasive. Less invasive and indirect evidence of the fungal infection by serology and imaging has been used for the early diagnosis of fungal infection before definitive results are available or when the definitive methods of diagnosis are suboptimal. Imaging in invasive fungal disease is a non-invasive biomarker that helps in the early diagnosis of invasive fungal disease but helps follow-up the infection during treatment. Different imaging modalities are used in the workup to evaluate fungal disease. The different imaging modalities have advantages and disadvantages at different sites in the body and may complement each other in the management of IFD. Positron emission tomography integrated with computed tomography with [18F]Fluorodeoxyglucose (FDG PET/CT) has helped manage IFD. The combined functional data from PET and anatomical data from the CT from almost the whole body allows noninvasive evaluation of IFD and provides a semiquantitative means of assessing therapy. FDG PET/CT adds value to anatomic-based only imaging modalities. The nonspecificity of FDG uptake has led to the evaluation of other tracers in the assessment of IFD. However, these are mainly still at the preclinical level and are yet to be translated to humans. FDG PET/CT remains the most widely evaluated radionuclide-based imaging modality in IFD management. The limitations of FDG PET/CT must be well understood, and more extensive prospective studies in uniform populations are needed to validate its role in the management of IFD that can be international guidelines.

Diagnosis and Treatment of Invasive Mold Diseases

Although invasive fungal diseases are relatively less common than superficial diseases, there has been an overall increase in their incidence. Here, I review the epidemiology, diagnosis, and treatment of invasive mold diseases (IMDs) such as aspergillosis, mucormycosis, hyalohyphomycosis, and phaeohyphomycosis. Histopathologic demonstration of tissue invasion by hyphae or recovery of mold by the culture of a specimen obtained by a sterile procedure provides definitive evidence of IMD. If IMD cannot be confirmed through invasive procedures, IMD can be diagnosed through clinical criteria such as the European Organization for Research and Treatment of Cancer/Invasive Fungal Infections Cooperative Group and the National Instituteof Allergy and Infectious Diseases Mycoses Study Group (EORTC/MSG) definitions. For initial primary therapy of invasive aspergillosis, voriconazole or isavuconazole is recommended and lipid formulations of amphotericin B are useful primary alternatives. Echinocandins are representative antifungal agents for salvage therapy. Treatment of invasive mucormycosis involves a combination of urgent surgical debridement of involved tissues and antifungal therapy. Lipid formulations of amphotericin B are the drug of choice for initial therapy. Isavuconazole or posaconazole can be used as salvage or step-down therapy. IMDs other than aspergillosis and mucormycosis include hyalohyphomycosis and phaeohyphomycosis, for which there is no standard therapy and the treatment depends on the clinical disease and status of the patient.

SARS-CoV-2 Associated Immune Dysregulation and COVID-Associated Pulmonary Aspergilliosis (CAPA): A Cautionary Tale

As the global SARS-CoV-2 pandemic continues to plague healthcare systems, it has become clear that opportunistic pathogens cause a considerable proportion of SARS-CoV-2-associated mortality and morbidity cases. Of these, Covid-Associated Pulmonary Aspergilliosis (CAPA) is a major concern with evidence that it occurs in the absence of traditional risk factors such as neutropenia and is diagnostically challenging for the attending physician. In this review, we focus on the immunopathology of SARS-CoV-2 and how this potentiates CAPA through dysregulation of local and systemic immunity as well as the unintended consequences of approved COVID treatments including corticosteroids and IL-6 inhibitors. Finally, we will consider how knowledge of the above may aid in the diagnosis of CAPA using current diagnostics and what treatment should be instituted in probable and confirmed cases.

Approach to fever in patients with neutropenia: a review of diagnosis and management

Febrile neutropenia (FN) is associated with mortality rates as high as 40%, highlighting the importance of appropriate clinical management in this patient population. The morbidity and mortality of FN can be attributed largely to infectious processes, with specific concern for infections caused by pathogens with antimicrobial resistance. Expeditious identification of responsible pathogens and subsequent initiation of empiric antimicrobial therapy is imperative. There are four commonly used guidelines, which have variable recommendations for empiric therapy in these populations. All agree that changes could be made once patients are stable and/or with an absolute neutrophil count (ANC) over 500 cells/mcL. Diagnostic advances have the potential to improve knowledge of pathogens responsible for FN and decrease time to results. In addition, more recent data show that rapid de-escalation or discontinuation of empiric therapy, regardless of ANC, may reduce days of therapy, adverse effects, and cost, without affecting clinical outcomes. Antimicrobial and diagnostic stewardship should be performed to identify, utilize, and respond to appropriate rapid diagnostic tests that will aid in the definitive management of this population.

A Visual and Comprehensive Review on COVID-19-Associated Pulmonary Aspergillosis (CAPA)

Coronavirus disease 19 (COVID-19)-associated pulmonary aspergillosis (CAPA) is a severe fungal infection complicating critically ill COVID-19 patients. Numerous retrospective and prospective studies have been performed to get a better grasp on this lethal co-infection. We performed a qualitative review and summarized data from 48 studies in which 7047 patients had been included, of whom 820 had CAPA. The pooled incidence of proven, probable or putative CAPA was 15.1% among 2953 ICU-admitted COVID-19 patients included in 18 prospective studies. Incidences showed great variability due to multiple factors such as discrepancies in the rate and depth of the fungal work-up. The pathophysiology and risk factors for CAPA are ill-defined, but therapy with corticosteroids and anti-interleukin-6 therapy potentially confer the biggest risk. Sampling for mycological work-up using bronchoscopy is the cornerstone for diagnosis, as imaging is often aspecific. CAPA is associated with an increased mortality, but we do not have conclusive data whether therapy contributes to an increased survival in these patients. We conclude our review with a comparison between influenza-associated pulmonary aspergillosis (IAPA) and CAPA.

Challenges with Utilizing the 1,3-Beta-d-Glucan and Galactomannan Assays To Diagnose Invasive Mold Infections in Immunocompromised Children

Establishing the diagnosis of invasive mold infections (IMI) in immunocompromised children is challenging due to nonspecific clinical presentations and the limited sensitivity of traditional culture-based methods. Rapid non-culture-based diagnostics such as the 1,3-beta-d-glucan and galactomannan assays have emerged as promising adjuncts to conventional diagnostic tests in adults. Available data suggest that 1,3-beta-d-glucan has limited accuracy in the pediatric population and is not recommended to be used for the diagnosis of IMI in children. On the other hand, the diagnostic performance of the serum and bronchoalveolar lavage galactomannan in immunocompromised children is comparable to results observed in adults and can be used as a screening tool in children at high risk of developing invasive aspergillosis (IA) who are not receiving mold-active antifungal prophylaxis and as a diagnostic tool in symptomatic children suspected of having IA. Herein, we summarize the available evidence for the use of these rapid non-culture-based diagnostics in immunocompromised children. We also summarize potential causes of false positivity for the 1,3-beta-d-glucan and galactomannan assays.

Diagnosis of Pneumonia Due to Invasive Molds

Pneumonia is the most common presentation of invasive mold infections (IMIs), and is pathogenetically characterized as angioinvasion by hyphae, resulting in tissue infarction and necrosis. Aspergillus species are the typical etiologic cause of mold pneumonia, with A. fumigatus in most cases, followed by the Mucorales species. Typical populations at risk include hematologic cancer patients on chemotherapy, bone marrow and solid organ transplant patients, and patients on immunosuppressive medications. Invasive lung disease due to molds is challenging to definitively diagnose based on clinical features and imaging findings alone, as these methods are nonspecific. Etiologic laboratory testing is limited to insensitive culture techniques, non-specific and not readily available PCR, and tissue biopsies, which are often difficult to obtain and impact on the clinical fragility of patients. Microbiologic/mycologic analysis has limited sensitivity and may not be sufficiently timely to be actionable. Due to the inadequacy of current diagnostics, clinicians should consider a combination of diagnostic modalities to prevent morbidity in patients with mold pneumonia. Diagnosis of IMIs requires improvement, and the availability of noninvasive methods such as fungal biomarkers, microbial cell-free DNA sequencing, and metabolomics-breath testing could represent a new era of timely diagnosis and early treatment of mold pneumonia.