Posaconazole for prevention of invasive pulmonary aspergillosis in critically ill influenza patients (POSA-FLU): a randomised, open-label, proof-of-concept trial

Profiling Bacteria in the Lungs of Patients with Severe Influenza Versus COVID-19 with or without Aspergillosis

Rationale: The influence of the lung bacterial microbiome, including potential pathogens, in patients with influenza-associated pulmonary aspergillosis (IAPA) or coronavirus disease (COVID-19)-associated pulmonary aspergillosis (CAPA) has yet to be explored. Objectives: To explore the composition of the lung bacterial microbiome and its association with viral and fungal infection, immunity, and outcome in severe influenza versus COVID-19 with or without aspergillosis. Methods: We performed a retrospective study in mechanically ventilated patients with influenza and COVID-19 with or without invasive aspergillosis in whom BAL for bacterial culture (with or without PCR) was obtained within 2 weeks after ICU admission. In addition, 16S rRNA gene sequencing data and viral and bacterial load of BAL samples from a subset of these patients, and of patients requiring noninvasive ventilation, were analyzed. We integrated 16S rRNA gene sequencing data with existing immune parameter datasets. Measurements and Main Results: Potential bacterial pathogens were detected in 20% (28/142) of patients with influenza and 37% (104/281) of patients with COVID-19, whereas aspergillosis was detected in 38% (54/142) of patients with influenza and 31% (86/281) of patients with COVID-19. A significant association between bacterial pathogens in BAL fluid and 90-day mortality was found only in patients with influenza, particularly patients with IAPA. Patients with COVID-19, but not patients with influenza, showed increased proinflammatory pulmonary cytokine responses to bacterial pathogens. Conclusions: Aspergillosis is more frequently detected in the lungs of patients with severe influenza than bacterial pathogens. Detection of bacterial pathogens associates with worse outcome in patients with influenza, particularly in those with IAPA, but not in patients with COVID-19. The immunological dynamics of tripartite viral-fungal-bacterial interactions deserve further investigation.

Damping excessive viral-induced IFN-γ rescues the impaired anti-Aspergillus host immune response in influenza-associated pulmonary aspergillosis

BACKGROUND

Influenza-associated pulmonary aspergillosis (IAPA) is a severe fungal superinfection in critically ill influenza patients that is of incompletely understood pathogenesis. Despite the use of contemporary therapies with antifungal and antivirals, mortality rates remain unacceptably high. We aimed to unravel the IAPA immunopathogenesis as a means to develop adjunctive immunomodulatory therapies.

METHODS

We used a murine model of IAPA to investigate how influenza predisposes to the development of invasive pulmonary aspergillosis. Immunocompetent mice were challenged with an intranasal instillation of influenza on day 0 followed by an orotracheal inoculation with Aspergillus 4 days later. Mice were monitored daily for overall health status, lung pathology with micro-computed tomography (μCT) and fungal burden with bioluminescence imaging (BLI). At endpoint, high parameter immunophenotyping, spatial transcriptomics, histopathology, dynamic phagosome biogenesis assays with live imaging, immunofluorescence staining, specialized functional phagocytosis and killing assays were performed.

FINDINGS

We uncovered an early exuberant influenza-induced interferon-gamma (IFN-γ) production as the major driver of immunopathology in IAPA and delineated the molecular mechanisms. Specifically, excessive IFN-γ production resulted in a defective Th17-immune response, depletion of macrophages, and impaired killing of Aspergillus conidia by macrophages due to the inhibition of NADPH oxidase-dependent activation of LC3-associated phagocytosis (LAP). Markedly, mice with partial or complete genetic ablation of IFN-γ had a restored Th17-immune response, LAP-dependent mechanism of killing and were fully protected from invasive fungal infection.

INTERPRETATION

Together, these results identify exuberant viral induced IFN-γ production as a major driver of immune dysfunction in IAPA, paving the way to explore the use of excessive viral-induced IFN-γ as a biomarker and new immunotherapeutic target in IAPA.

FUNDING

This research was funded by the Research Foundation Flanders (FWO), project funding under Grant G053121N to JW, SHB and GVV; G057721N, G0G4820N to GVV; 1506114 N to KL and GVV; KU Leuven internal funds (C24/17/061) to GVV, clinical research funding to JW, Research Foundation Flanders (FWO) aspirant mandate under Grant 1186121N/1186123 N to LS, 11B5520N to FS, 1SF2222N to EV and 11M6922N/11M6924N to SF, travel grants V428023N, K103723N, K217722N to LS. FLvdV was supported by a Vidi grant of the Netherlands Association for Scientific Research. FLvdV, JW, AC and GC were supported by the Europeans Union's Horizon 2020 research and innovation program under grant agreement no 847507 HDM-FUN. AC was also supported by the Fundação para a Ciência e a Tecnologia (FCT), with the references UIDB/50026/2020, UIDP/50026/2020, PTDC/MED-OUT/1112/2021 (https://doi.org/10.54499/PTDC/MED-OUT/1112/2021), and 2022.06674.PTDC (http://doi.org/10.54499/2022.06674.PTDC); and the "la Caixa" Foundation under the agreement LCF/PR/HR22/52420003 (MICROFUN).

Influenza-associated and COVID-19-associated pulmonary aspergillosis in critically ill patients

Influenza-associated pulmonary aspergillosis (IAPA) and COVID-19-associated pulmonary aspergillosis (CAPA) are increasingly recognised as important complications in patients requiring intensive care for severe viral pneumonia. The diagnosis can typically be made in 10-20% of patients with severe influenza or COVID-19, but only when appropriate diagnostic tools are used. Bronchoalveolar lavage sampling for culture, galactomannan testing, and PCR forms the cornerstone of diagnosis, whereas visual examination of the tracheobronchial tract during bronchoscopy is required to detect invasive Aspergillus tracheobronchitis. Azoles are the first-choice antifungal drugs, with liposomal amphotericin B as an alternative in settings where azole resistance is prevalent. Despite antifungal therapy, IAPA and CAPA are associated with poor outcomes, with fatality rates often exceeding 50%. In this Review, we discuss the mechanistic and clinical aspects of IAPA and CAPA. Moreover, we identify crucial knowledge gaps and formulate directions for future research.

Dosing of IV posaconazole to treat critically ill patients with invasive pulmonary aspergillosis: a population pharmacokinetics modelling and simulation study

BACKGROUND

Posaconazole is used for the prophylaxis and treatment of invasive fungal infections in critically ill patients. Standard dosing was shown to result in adequate attainment of the prophylaxis Cmin target (0.7 mg/L) but not of the treatment Cmin target (1.0 mg/L).

OBJECTIVES

To provide an optimized posaconazole dosing regimen for IV treatment of patients with invasive pulmonary aspergillosis in the ICU.

METHODS

A population pharmacokinetics (popPK) model was developed using data from the POSA-FLU PK substudy (NCT03378479). Monte Carlo simulations were performed to assess treatment Cmin and AUC0-24 PTA. PTA ≥90% was deemed clinically acceptable. PopPK modelling and simulation were performed using NONMEM 7.5.

RESULTS

Thirty-one patients with intensive PK sampling were included in the PK substudy, contributing 532 posaconazole plasma concentrations. The popPK of IV posaconazole was best described by a two-compartment model with linear elimination. Interindividual variability was estimated on clearance and volume of distribution in central and peripheral compartments. Posaconazole peripheral volume of distribution increased with bodyweight. An optimized loading regimen of 300 mg q12h and 300 mg q8h in the first two treatment days achieved acceptable PTA by Day 3 in patients <100 kg and ≥100 kg, respectively. A maintenance regimen of 400 mg q24h ensured ≥90% Cmin PTA, whereas the standard 300 mg q24h was sufficient to achieve the AUC0-24 target throughout 14 days, irrespective of bodyweight.

CONCLUSIONS

We have defined a convenient, optimized IV posaconazole dosing regimen that was predicted to attain the treatment target in critically ill patients with invasive aspergillosis.

Novel antifungals and treatment approaches to tackle resistance and improve outcomes of invasive fungal disease

SUMMARYFungal infections are on the rise, driven by a growing population at risk and climate change. Currently available antifungals include only five classes, and their utility and efficacy in antifungal treatment are limited by one or more of innate or acquired resistance in some fungi, poor penetration into "sequestered" sites, and agent-specific side effect which require frequent patient reassessment and monitoring. Agents with novel mechanisms, favorable pharmacokinetic (PK) profiles including good oral bioavailability, and fungicidal mechanism(s) are urgently needed. Here, we provide a comprehensive review of novel antifungal agents, with both improved known mechanisms of actions and new antifungal classes, currently in clinical development for treating invasive yeast, mold (filamentous fungi), Pneumocystis jirovecii infections, and dimorphic fungi (endemic mycoses). We further focus on inhaled antifungals and the role of immunotherapy in tackling fungal infections, and the specific PK/pharmacodynamic profiles, tissue distributions as well as drug-drug interactions of novel antifungals. Finally, we review antifungal resistance mechanisms, the role of use of antifungal pesticides in agriculture as drivers of drug resistance, and detail detection methods for antifungal resistance.

Severe mold fungal infections in critically ill patients with COVID-19

The SARS-CoV-2 pandemic put an unprecedented strain on modern societies and healthcare systems. A significantly higher incidence of invasive fungal co-infections was noted compared with the pre-COVID-19 era, adding new diagnostic and therapeutic challenges in the critical care setting. In the current narrative review, we focus on invasive mold infections caused by Aspergillus and Mucor species in critically ill COVID-19 patients. We discuss up-to-date information on the incidence, pathogenesis, diagnosis and treatment of these mold-COVID-19 co-infections, as well as recommendations on preventive and prophylactic interventions. Traditional risk factors were often not recognized in COVID-19-associated aspergillosis and mucormycosis, highlighting the role of other determinant risk factors. The associated patient outcomes were worse compared with COVID-19 patients without mold co-infection.

Integrating genetic and immune factors to uncover pathogenetic mechanisms of viral-associated pulmonary aspergillosis

Invasive pulmonary aspergillosis is a severe fungal infection primarily affecting immunocompromised patients. Individuals with severe viral infections have recently been identified as vulnerable to developing invasive fungal infections. Both influenza-associated pulmonary aspergillosis (IAPA) and COVID-19-associated pulmonary aspergillosis (CAPA) are linked to high mortality rates, emphasizing the urgent need for an improved understanding of disease pathogenesis to unveil new molecular targets with diagnostic and therapeutic potential. The recent establishment of animal models replicating the co-infection context has offered crucial insights into the mechanisms that underlie susceptibility to disease. However, the development and progression of human viral-fungal co-infections exhibit a significant degree of interindividual variability, even among patients with similar clinical conditions. This observation implies a significant role for host genetics, but information regarding the genetic basis for viral-fungal co-infections is currently limited. In this review, we discuss how genetic factors known to affect either antiviral or antifungal immunity could potentially reveal pathogenetic mechanisms that predispose to IAPA or CAPA and influence the overall disease course. These insights are anticipated to foster further research in both pre-clinical models and human patients, aiming to elucidate the complex pathophysiology of viral-associated pulmonary aspergillosis and contributing to the identification of new diagnostic and therapeutic targets to improve the management of these co-infections.

Study protocol: A randomized, double-blind, placebo-controlled trial of isavuconazole prophylaxis for the prevention of covid-19-associated pulmonary aspergillosis

Background

During the early stages of the coronavirus disease 2019 (COVID-19) pandemic, those with severe COVID-19 infection were at risk for a number of opportunistic infections including COVID-19-associated pulmonary aspergillosis (CAPA). We initiated a randomized clinical trial to evaluate whether isavuconazole, a triazole antifungal, could prevent CAPA and improve survival in patients admitted to the ICU with severe COVID-19 infection.

Methods

We designed a phase III/IV randomized, double-blind, two-arm, placebo-controlled trial evaluating standard of care (SOC) plus isavuconazole versus SOC plus placebo and were to enroll participants admitted to the ICU with severe COVID-19 infection at three medical centers in California, United States. The projected sample size was 162 participants.

Results

Due to poor enrollment and the declining number of COVID-19 cases over time, the study was terminated after 7 participants were enrolled, all enrolled at one study site (UC San Diego Health). CAPA was suspected in two participants and they were started on open-label isavuconazole. One was withdrawn due to possible isavuconazole-related adverse side effects.

Conclusion

Enrollment was slower-than-expected due to multiple factors, including competing COVID-19-related studies and hesitancy from potential study participants or their families to join the study. Our experience highlights some of the difficulties in planning and running a clinical trial focused on fungal superinfections involving severely ill patients during the height of the COVID-19 pandemic. Lessons learned from this study will help in the design of proposed studies examining antifungal prophylaxis against aspergillosis following other severe respiratory viral infections.

Invasive pulmonary aspergillosis among patients with severe community-acquired pneumonia and influenza in ICUs: a retrospective cohort study

RATIONALE

The prevalence, clinical characteristics, and outcomes of invasive pulmonary aspergillosis in patients with severe community-acquired pneumonia (CAP) in intensive care units remain underestimated because of the lack of a disease-recognition scheme and the inadequacy of diagnostic tests.

OBJECTIVES

To identify the prevalence, risk factors, and outcomes of severe CAP complicated with invasive pulmonary aspergillosis (IPA) in intensive care units (ICUs).

METHODS

We conducted a retrospective cohort study including recruited 311 ICU-hospitalized patients with severe CAP without influenza or with influenza. Bronchoalveolar lavage fluid (BALF) samples were from all patients and subjected to mycological testing. Patients were categorized as having proven or probable Aspergillus infection using a modified form of the AspICU algorithm comprising clinical, radiological, and mycological criteria.

MEASUREMENTS AND MAIN RESULTS

Of the 252 patients with severe CAP and 59 influenza patients evaluated, 24 met the diagnostic criteria for proven or probable Aspergillus infection in the CAP group and 9 patients in the influenza group, giving estimated prevalence values of 9.5% and 15.3%, respectively. COPD and the use of inhaled corticosteroids were independent risk factors for IPA. IPA in patients with severe CAP was significantly associated with the duration of mechanical support, the length of ICU stay, and the 28-day mortality.

CONCLUSIONS

An aggressive diagnostic approach for IPA patients with severe CAP and not only influenza or COVID-19 should be pursued. Further randomized controlled trials need to evaluate the timing, safety, and efficacy of antifungal therapy in reducing IPA incidence and improving clinical outcomes.

Personalized Antifungal Therapy Through Model-Informed Precision Dosing of Posaconazole

BACKGROUND AND OBJECTIVE

Posaconazole is a pharmacotherapeutic pillar for prophylaxis and treatment of invasive fungal diseases. Dose individualization is of utmost importance as achieving adequate antifungal exposure is associated with improved outcome. This study aimed to select and evaluate a model-informed precision dosing strategy for posaconazole.

METHODS

Available population pharmacokinetic models for posaconazole administered as a solid oral tablet were extracted from the literature and evaluated using data from a previously published prospective study combined with data collected during routine clinical practice. External evaluation and selection of the most accurate and precise model was based on graphical goodness-of-fit and predictive performance. Measures for bias and imprecision included mean percentage error (MPE) and normalized relative root mean squared error (NRMSE), respectively. Subsequently, the best-performing model was evaluated for its a posteriori fit-for-purpose and its suitability in a limited sampling strategy.

RESULTS

Seven posaconazole models were evaluated using 764 posaconazole plasma concentrations from 143 patients. Multiple models showed adequate predictive performance illustrated by acceptable goodness-of-fit and MPE and NRMSE below ± 10% and ± 25%, respectively. In the fit-for-purpose analysis, the selected model showed adequate a posteriori predictive performance. Bias and imprecision were lowest in the presence of two prior measurements. Additionally, this model showed to be useful in a limited sampling strategy as it adequately predicted total posaconazole exposure from one (non-)trough concentration.

CONCLUSION

We validated an MIPD strategy for posaconazole for its fit-for-purpose. Thereby, this study is an important first step towards MIPD-supported posaconazole dosage optimization with the goal to improve antifungal treatment in clinical practice.

COVID-19 associated pulmonary aspergillosis in critically-ill patients: a prospective multicenter study in the era of Delta and Omicron variants

BACKGROUND

During the first COVID-19 pandemic wave, COVID-19-associated pulmonary aspergillosis (CAPA) has been reported in up to 11-28% of critically ill COVID-19 patients and associated with increased mortality. As new SARS-CoV-2 variants emerged, the characteristics of critically ill COVID-19 patients have evolved, particularly in the era of Omicron. The purpose of this study is to investigate the characteristics of CAPA in the era of new variants.

METHODS

This is a prospective multicenter observational cohort study conducted in France in 36 participating intensive care units (ICU), between December 7th, 2021 and April 26th 2023. Diagnosis criteria of CAPA relied on European Confederation of Medical Mycology (ECMM)/International Society for Human & Animal Mycology (ISHAM) consensus criteria.

RESULTS

566 patients were included over the study period. The prevalence of CAPA was 5.1% [95% CI 3.4-7.3], and rose to 9.1% among patients who required invasive mechanical ventilation (IMV). Univariable analysis showed that CAPA patients were more frequently immunosuppressed and required more frequently IMV support, vasopressors and renal replacement therapy during ICU stay than non-CAPA patients. SAPS II score at ICU admission, immunosuppression, and a SARS-CoV-2 Delta variant were independently associated with CAPA in multivariable logistic regression analysis. Although CAPA was not significantly associated with day-28 mortality, patients with CAPA experienced a longer duration of mechanical ventilation and ICU stay.

CONCLUSION

This study contributes valuable insights into the prevalence, characteristics, and outcomes of CAPA in the era of Delta and Omicron variants. We report a lower prevalence of CAPA (5.1%) among critically-ill COVID-19 patients than previously reported, mainly affecting intubated-patients. Duration of mechanical ventilation and ICU stay were significantly longer in CAPA patients.

Latest developments in early diagnosis and specific treatment of severe influenza infection

Influenza pandemics are unpredictable recurrent events with global health, economic, and social consequences. The objective of this review is to provide an update on the latest developments in early diagnosis and specific treatment of the disease and its complications, particularly with regard to respiratory organ failure. Despite advances in treatment, the rate of mortality in the intensive care unit remains approximately 30%. Therefore, early identification of potentially severe viral pneumonia is extremely important to optimize treatment in these patients. The pathogenesis of influenza virus infection depends on viral virulence and host response. Thus, in some patients, it is associated with an excessive systemic response mediated by an authentic cytokine storm. This process leads to severe primary pneumonia and acute respiratory distress syndrome. Initial prognostication in the emergency department based on comorbidities, vital signs, and biomarkers (e.g., procalcitonin, ferritin, human leukocyte antigen-DR, mid-regional proadrenomedullin, and lactate) is important. Identification of these biomarkers on admission may facilitate clinical decision-making to determine early admission to the hospital or the intensive care unit. These decisions are reached considering pathophysiological circumstances that are associated with a poor prognosis (e.g., bacterial co-infection, hyperinflammation, immune paralysis, severe endothelial damage, organ dysfunction, and septic shock). Moreover, early implementation is important to increase treatment efficacy. Based on a limited level of evidence, all current guidelines recommend using oseltamivir in this setting. The possibility of drug resistance should also be considered. Alternative options include other antiviral drugs and combination therapies with monoclonal antibodies. Importantly, it is not recommended to use corticosteroids in the initial treatment of these patients. Furthermore, the implementation of supportive measures for respiratory failure is essential. Current recommendations are limited, heterogeneous, and not regularly updated. Early intubation and mechanical ventilation is the basic treatment for patients with severe respiratory failure. Prone ventilation should be promptly performed in patients with acute respiratory distress syndrome, while early tracheostomy should be considered in case of planned prolonged mechanical ventilation. Clinical trials on antiviral treatment and respiratory support measures specifically for these patients, as well as specific recommendations for different at-risk populations, are necessary to improve outcomes.

Prevalence, Risk Factors, Clinical Features, and Outcome of Influenza-Associated Pulmonary Aspergillosis in Critically Ill Patients: A Systematic Review and Meta-Analysis

BACKGROUND

Influenza-associated pulmonary aspergillosis (IAPA) increasingly is being reported in critically ill patients. We conducted this systematic review and meta-analysis to examine the prevalence, risk factors, clinical features, and outcomes of IAPA.

STUDY QUESTION

What are the prevalence, risk factors, clinical features, and outcomes of IAPA in critically ill patients?

STUDY DESIGN AND METHODS

Studies reporting IAPA were searched in the following databases: PubMed MEDLINE, CINAHL, Cochrane Library, Embase, Scopus, Cochrane Trials, and ClinicalTrials.gov. We performed one-group meta-analysis on risk factors, clinical features, morbidity, and mortality using random effects models.

RESULTS

We included 10 observational studies with 1,720 critically ill patients with influenza, resulting in an IAPA prevalence of 19.2% (331 of 1,720). Patients who had undergone organ transplantation (OR, 4.8; 95% CI, 1.7-13.8; I2 = 45%), harbored a hematogenous malignancy (OR, 2.5; 95% CI, 1.5-4.1; I2 = 0%), were immunocompromised (OR, 2.2; 95% CI, 1.6-3.1; I2 = 0%), and underwent prolonged corticosteroid use before admission (OR, 2.4; 95% CI, 1.4-4.3; I2 = 51%) were found to be at a higher risk of IAPA developing. Commonly reported clinical and imaging features were not particularly associated with IAPA. However, IAPA was associated with more severe disease progression, a higher complication rate, and longer ICU stays and required more organ supports. Overall, IAPA was associated with a significantly elevated ICU mortality rate (OR, 2.6; 95% CI, 1.8-3.8; I2 = 0%).

INTERPRETATION

IAPA is a common complication of severe influenza and is associated with increased mortality. Early diagnosis of IAPA and initiation of antifungal treatment are essential, and future research should focus on developing a clinical algorithm.

TRIAL REGISTRY

International Prospective Register of Systematic Reviews; No.: CRD42022284536; URL: https://www.crd.york.ac.uk/prospero/.

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.

COVID-19 associated Pulmonary Aspergillosis in Patients Admitted to the Intensive Care Unit: Impact of Antifungal Prophylaxis

Early after the beginning of the coronavirus disease 2019 (COVID-19)-pandemic, it was observed that critically ill patients in the intensive care unit (ICU) were susceptible to developing secondary fungal infections, particularly COVID-19 associated pulmonary aspergillosis (CAPA). Here we report our local experience on the impact of mold active antifungal prophylaxis on CAPA occurrence in critically ill COVID-19 patients. This is a monocentric, prospective cohort study including all consecutive patients with COVID-19 associated acute respiratory failure who were admitted to our local medical ICU. Based on the treating physician's discretion, patients may have received antifungal prophylaxis or not. All patients were retrospectively characterized as having CAPA according to the 2020 ECMM/ISHAM consensus definitions. Seventy-seven patients were admitted to our medical ICU during April 2020 and May 2021 and included in the study. The majority of patients received invasive-mechanical ventilation (61%). Fifty-three patients (68.8%) received posaconazole prophylaxis. Six cases of probable CAPA were diagnosed within clinical routine management. All six cases were diagnosed in the non-prophylaxis group. The incidence of CAPA in the overall study cohort was 0.57 events per 100 ICU days and 2.20 events per 100 ICU days in the non-prophylaxis group. No difference of cumulative 84-days survival could be observed between the two groups (p = 0.115). In this monocentric cohort, application of posaconazole prophylaxis in patients with COVID-19 associated respiratory failure did significantly reduce the rate of CAPA.

Early attainment of isavuconazole target concentration using an increased loading dose in critically ill patients with extracorporeal membrane oxygenation

BACKGROUND

In critically ill patients with extracorporeal membrane oxygenation (ECMO) attainment of target concentration of isavuconazole is delayed using the routine loading dose.

OBJECTIVES

We investigated the influence of increasing the first loading dose of isavuconazole on plasma concentrations in critically ill patients treated with ECMO.

METHODS

Fifteen patients were included in this study, and isavuconazole concentrations were measured at several timepoints starting 2 h after the first isavuconazole dose up to 168 h. By interim analysis of isavuconazole concentrations and meticulous screening for adverse events, the first loading dose was stepwise increased from 200 to 300 mg, and finally to 400 mg.

RESULTS

Seven of 15 patients (47%) received standard isavuconazole loading dosage with 200 mg as the first dose, 3/15 (20%) received 300 mg, and 5/15 (33%) received 400 mg isavuconazole as the first dose, followed by subsequent standard dosing in all patients. In patients receiving 400 mg as the first dose all isavuconazole concentrations were significantly higher at timepoints up to the first 24 h, resulting in higher proportions of isavuconazole concentrations ≥1 mg/L compared with patients with other loading dosages. In timepoints ≥24 h after isavuconazole initiation all patient groups reached comparable plasma concentrations, regardless of the first loading dose regimen. We did not observe concentrations above ≥5 mg/L or any adverse events related to isavuconazole administration.

CONCLUSIONS

In critically ill patients with ECMO the 400 mg loading dose of isavuconazole resulted in immediate median isavuconazole plasma concentrations ≥1 mg/L and remained constant above this threshold after the first loading dose.

Invasive pulmonary aspergillosis in the intensive care unit: current challenges and best practices

The prevalence of invasive pulmonary aspergillosis (IPA) is growing in critically ill patients in the intensive care unit (ICU). It is increasingly recognized in immunocompetent hosts and immunocompromised ones. IPA frequently complicates both severe influenza and severe coronavirus disease 2019 (COVID-19) infection. It continues to represent both a diagnostic and therapeutic challenge and can be associated with significant morbidity and mortality. In this narrative review, we describe the epidemiology, risk factors and disease manifestations of IPA. We discuss the latest evidence and current published guidelines for the diagnosis and management of IPA in the context of the critically ill within the ICU. Finally, we review influenza-associated pulmonary aspergillosis (IAPA), COVID-19-associated pulmonary aspergillosis (CAPA) as well as ongoing and future areas of research.

Invasive pulmonary aspergillosis in the ICU: tale of a broadening risk profile

PURPOSE OF REVIEW

In the absence of histopathological proof, the diagnosis of invasive pulmonary aspergillosis (IPA) is usually based on mycology (not on tissue), medical imaging, and the patient's risk profile for acquiring invasive fungal disease. Here, we review the changes in risk profile for IPA that took place over the past decades.

RECENT FINDINGS

In the early 2000s IPA was considered exclusively a disease of immunocompromised patients. Particularly in the context of critical illness, the risk profile has been broadened steadily. Acute viral infection by influenza or SARS-Cov-2 are now well recognized risk factors for IPA.

SUMMARY

The classic risk profile ('host factors') reflecting an immunocompromised status was first enlarged by a spectrum of chronic conditions such as AIDS, cirrhosis, and chronic obstructive pulmonary disease. In the presence of critical illness, especially characterized by sepsis and/or severe respiratory distress, any chronic condition could add to the risk profile. Recently, acute viral infections have been associated with IPA leading to the concepts of influenza-associated IPA and COVID-19-associated IPA. These viral infections may affect patients without underlying disease. Hence, the risk for IPA is now a reality for ICU patients, even in the absence of any chronic conditions.

Identification of the shared gene signatures between pulmonary fibrosis and pulmonary hypertension using bioinformatics analysis

Pulmonary fibrosis (PF) and pulmonary hypertension (PH) have common pathophysiological features, such as the significant remodeling of pulmonary parenchyma and vascular wall. There is no effective specific drug in clinical treatment for these two diseases, resulting in a worse prognosis and higher mortality. This study aimed to screen the common key genes and immune characteristics of PF and PH by means of bioinformatics to find new common therapeutic targets. Expression profiles are downloaded from the Gene Expression Database. Weighted gene co-expression network analysis is used to identify the co-expression modules related to PF and PH. We used the ClueGO software to enrich and analyze the common genes in PF and PH and obtained the protein-protein interaction (PPI) network. Then, the differential genes were screened out in another cohort of PF and PH, and the shared genes were crossed. Finally, RT-PCR verification and immune infiltration analysis were performed on the intersection genes. In the result, the positive correlation module with the highest correlation between PF and PH was determined, and it was found that lymphocyte activation is a common feature of the pathophysiology of PF and PH. Eight common characteristic genes (ACTR2, COL5A2, COL6A3, CYSLTR1, IGF1, RSPO3, SCARNA17 and SEL1L) were gained. Immune infiltration showed that compared with the control group, resting CD4 memory T cells were upregulated in PF and PH. Combining the results of crossing characteristic genes in ImmPort database and RT-PCR, the important gene IGF1 was obtained. Knocking down IGF1 could significantly reduce the proliferation and apoptosis resistance in pulmonary microvascular endothelial cells, pulmonary smooth muscle cells, and fibroblasts induced by hypoxia, platelet-derived growth factor-BB (PDGF-BB), and transforming growth factor-β1 (TGF-β1), respectively. Our work identified the common biomarkers of PF and PH and provided a new candidate gene for the potential therapeutic targets of PF and PH in the future.

[Anti-infective treatment of fungal infections by Candida and Aspergillus]

BACKGROUND

Invasive fungal infections caused by Candida or Aspergillus are associated with a high mortality. Knowledge about the risk factors, diagnosis and treatment management is crucial for improving the survival of those affected.

OBJECTIVE

To give a practical overview about risk factors and treatment management of Candida and Aspergillus infections as well as providing an outlook on new antifungal agents.

MATERIAL AND METHODS

Summary of the relevant literature and recommendations on candidemia and invasive candidiasis as well as invasive and chronic pulmonary aspergillosis.

RESULTS

The first line treatment of candidemia and invasive candidiasis are echinocandins including caspofungin, anidulafungin and micafungin. Regular blood cultures have to be taken to determine the duration of treatment. After the first negative control blood culture treatment should be continued for another 14 days. The first line treatment of invasive pulmonary aspergillosis is azoles including voriconazole and isavuconazole. The duration of treatment depends on disease severity and is recommended for 6-12 weeks. The duration of treatment for chronic pulmonary aspergillosis is 6-12 months. Therapeutic drug monitoring is recommended for voriconazole and for posaconazole. New antifungal agents including olorofim, fosmanogepix, opelconazole, rezafungin or ibrexafungerp will broaden the therapeutic spectrum in the foreseeable future.

CONCLUSION

Knowledge about risk factors and the correct treatment management is crucial for the survival of patients with invasive fungal infections.

Antifungal prophylaxis and pre-emptive therapy: When and how?

The growing pool of critically ill or immunocompromised patients leads to a constant increase of life-threatening invasive infections by fungi such as Aspergillus spp., Candida spp. and Pneumocystis jirovecii. In response to this, prophylactic and pre-emptive antifungal treatment strategies have been developed and implemented for high-risk patient populations. The benefit by risk reduction needs to be carefully weighed against potential harm caused by prolonged exposure against antifungal agents. This includes adverse effects and development of resistance as well as costs for the healthcare system. In this review, we summarise evidence and discuss advantages and downsides of antifungal prophylaxis and pre-emptive treatment in the setting of malignancies such as acute leukaemia, haematopoietic stem cell transplantation, CAR-T cell therapy, and solid organ transplant. We also address preventive strategies in patients after abdominal surgery and with viral pneumonia as well as individuals with inherited immunodeficiencies. Notable progress has been made in haematology research, where strong recommendations regarding antifungal prophylaxis and pre-emptive treatment are backed by data from randomized controlled trials, whereas other critical areas still lack high-quality evidence. In these areas, paucity of definitive data translates into centre-specific strategies that are based on interpretation of available data, local expertise, and epidemiology. The development of novel immunomodulating anticancer drugs, high-end intensive care treatment and the development of new antifungals with new modes of action, adverse effects and routes of administration will have implications on future prophylactic and pre-emptive approaches.

A Pathology-based Case Series of Influenza- and COVID-19-associated Pulmonary Aspergillosis: The Proof Is in the Tissue

Rationale: Invasive pulmonary aspergillosis has emerged as a frequent coinfection in severe coronavirus disease (COVID-19), similarly to influenza, yet the clinical invasiveness is more debated. Objectives: We investigated the invasive nature of pulmonary aspergillosis in histology specimens of influenza and COVID-19 ICU fatalities in a tertiary care center. Methods: In this monocentric, descriptive, retrospective case series, we included adult ICU patients with PCR-proven influenza/COVID-19 respiratory failure who underwent postmortem examination and/or tracheobronchial biopsy during ICU admission from September 2009 until June 2021. Diagnosis of probable/proven viral-associated pulmonary aspergillosis (VAPA) was made based on the Intensive Care Medicine influenza-associated pulmonary aspergillosis and the European Confederation of Medical Mycology (ECMM) and the International Society for Human and Animal Mycology (ISHAM) COVID-19-associated pulmonary aspergillosis consensus criteria. All respiratory tissues were independently reviewed by two experienced pathologists. Measurements and Main Results: In the 44 patients of the autopsy-verified cohort, 6 proven influenza-associated and 6 proven COVID-19-associated pulmonary aspergillosis diagnoses were identified. Fungal disease was identified as a missed diagnosis upon autopsy in 8% of proven cases (n = 1/12), yet it was most frequently found as confirmation of a probable antemortem diagnosis (n = 11/21, 52%) despite receiving antifungal treatment. Bronchoalveolar lavage galactomannan testing showed the highest sensitivity for VAPA diagnosis. Among both viral entities, an impeded fungal growth was the predominant histologic pattern of pulmonary aspergillosis. Fungal tracheobronchitis was histologically indistinguishable in influenza (n = 3) and COVID-19 (n = 3) cases, yet macroscopically more extensive at bronchoscopy in influenza setting. Conclusions: A proven invasive pulmonary aspergillosis diagnosis was found regularly and with a similar histological pattern in influenza and in COVID-19 ICU case fatalities. Our findings highlight an important need for VAPA awareness, with an emphasis on mycological bronchoscopic work-up.

Superinfections in COVID-19 patients receiving extracorporeal membrane oxygenation support

BACKGROUND

The risk of superinfections and associations with mortality among patients with corona virus disease 2019 (COVID-19) receiving veno-venous extracorporeal membrane oxygenation (VV-ECMO) is poorly elucidated.

METHOD

We identified all patients with COVID-19 treated with VV-ECMO >24 h at Rigshospitalet, Denmark from March 2020 to December 2021. Data were obtained by review of medical files. Associations between superinfections and mortality were assessed by logistic regression analyses adjusted for sex and age.

RESULTS

Fifty patients, median age 53 years (interquartile range [IQR] 45-59), 66% male, were included. Median time on VV-ECMO was 14.5 days (IQR 6.3-23.5), 42% were discharged from hospital alive. Bacteremia, ventilator associated pneumonia (VAP), invasive candidiasis, pulmonary aspergillosis, herpes simplex virus, and cytomegalovirus (CMV) were detected in 38%, 42%, 12%, 12%, 14%, and 20% of patients, respectively. No patients with pulmonary aspergillosis survived. CMV was associated with increased risk of death, odds ratio 12.6 (95% confidence interval 1.9-257, p = .05), whereas we found no associations between other superinfections and risk of death.

CONCLUSION

Bacteremia and VAP are common but does not seem to affect mortality, whereas pulmonary aspergillosis and CMV are associated with poor prognosis among COVID-19 patients treated with VV-ECMO.

Dysregulated Pulmonary Inflammatory Responses Exacerbate the Outcome of Secondary Aspergillosis Following Influenza

Inhalation of airborne conidia of the ubiquitous fungus Aspergillus fumigatus commonly occurs but invasive aspergillosis is rare except in profoundly immunocompromised persons. Severe influenza predisposes patients to invasive pulmonary aspergillosis by mechanisms that are poorly defined. Using a post-influenza aspergillosis model, we found that superinfected mice had 100% mortality when challenged with A. fumigatus conidia on days 2 and 5 (early stages) of influenza A virus infection but 100% survival when challenged on days 8 and 14 (late stages). Influenza-infected mice superinfected with A. fumigatus had increased levels of the pro-inflammatory cytokines and chemokines IL-6, TNFα, IFNβ, IL-12p70, IL-1α, IL-1β, CXCL1, G-CSF, MIP-1α, MIP-1β, RANTES and MCP-1. Surprisingly, on histopathological analysis, superinfected mice did not have greater lung inflammation compared with mice infected with influenza alone. Mice infected with influenza had dampened neutrophil recruitment to the lungs following subsequent challenge with A. fumigatus , but only if the fungal challenge was executed during the early stages of influenza infection. However, influenza infection did not have a major effect on neutrophil phagocytosis and killing of A. fumigatus conidia. Moreover, minimal germination of conidia was seen on histopathology even in the superinfected mice. Taken together, our data suggest that the high mortality rate seen in mice during the early stages of influenza-associated pulmonary aspergillosis is multifactorial, with a greater contribution from dysregulated inflammation than microbial growth.

Importance

Severe influenza is a risk factor for fatal invasive pulmonary aspergillosis; however, the mechanistic basis for the lethality is unclear. Utilizing an influenza-associated pulmonary aspergillosis (IAPA) model, we found that mice infected with influenza A virus followed by A. fumigatus had 100% mortality when superinfected during the early stages of influenza but survived at later stages. While superinfected mice had dysregulated pulmonary inflammatory responses compared to controls, they had neither increased inflammation nor extensive fungal growth. Although influenza-infected mice had dampened neutrophil recruitment to the lungs following subsequent challenge with A. fumigatus , influenza did not affect the ability of neutrophils to clear the fungi. Our data suggest that the lethality seen in our model IAPA is multifactorial with dysregulated inflammation being a greater contributor than uncontrollable microbial growth. If confirmed in humans, our findings provide a rationale for clinical studies of adjuvant anti-inflammatory agents in the treatment of IAPA.

Invasive fungal disease in COVID-19 patients: a single-center prospective observational study

Background

Invasive fungal diseases (IFDs) are caused by fungal infections that manifest as serious secondary infections in patients with COVID-19. The increased morbidity and mortality rates are most frequently observed in patients with COVID-19-associated pulmonary aspergillosis (CAPA) and COVID-19-associated candidiasis (CAC). CAPA is the most frequently encountered infection with an incidence rate of 0.7-7.7%, while CAC is a less common and less studied fungal infection in COVID-19 patients.

Materials and methods

The present article is a prospective observational single-center study that was conducted between 1 September 2021 and 24 December 2021, involving 6,335 patients who were admitted to COVID Hospital "Batajnica," University Clinical Center of Serbia, Belgrade.

Results

Of the 6,335 patients hospitalized during the four-month period of the study, 120 patients (1.86%) who had a proven diagnosis of IFD were included in the study. These patients were divided into two groups: CAPA patients (n = 63) and CAC patients (n = 56); however, one of the 120 patients was diagnosed with Cryptoccocus neoformans infection. The mean age of the study population was 65.7 ± 13.9 years, and 78 (65.5%) of them were men. The patients were identified to have the following non-malignant comorbidities: arterial hypertension in 62 (52.1%) patients, diabetes mellitus in 34 (28.65), pre-existing lung damage similar to that observed in COPD and asthma in 20 (16.8%), and chronic renal insufficiency in 13 (10.9%) patients. The hematological malignancies were found to be the most prevalent malignancies and were identified in 20 (16.8%) patients, particularly in CAPA patients [11 (17.5%); p < 0.041]. Fiberoptic bronchoscopy with bronchoalveolar lavage fluid (BALF) and microscopic examination confirmed the presence of fungal infections in 17 (14.3%) patients. Serology testing was also performed in the majority of cases. Antibodies against Aspergillus spp. and Candida spp. were predominantly found in CAPA patients (p < 0.001). The patients were also tested for the presence of (1-3)-β-D glucan (p < 0.019), galactomannan, and mannan in the specimens. Blood cultures were found to be positive in 45 (37.8%) patients, mostly in CAC patients. Mechanical ventilation was applied in 41 (34.5%) patients, while a non-invasive technique, such as continuous positive airway pressure (CPAP) or high-flow nasal cannula (HFNC), was used in 20 (16.8%) patients. The following antifungals were administered: echinocandins in 42 (35.3%), voriconazole in 30 (25.2%), and fluconazole in 27 (22.7%) patients. Most of the patients received systemic corticosteroids (mainly methylprednisolone), while 11 (9.16%) received favipiravir, 32 (26.67%) remdesivir, 8 (6.67%) casirivimab/imdevimab, and 5 (4.16%) sotrovimab. The outcome was lethal in 76 (63.9%) patients, predominantly CAC patients (p < 0.001).

Conclusion

Invasive fungal disease is a severe complication associated with COVID-19 and accounts for increased mortality in these patients. Early identification and appropriate treatment may provide a favorable outcome.

Prevention of acquired invasive fungal infection with decontamination regimen in mechanically ventilated ICU patients: a pre/post observational study

BACKGROUND

Invasive fungal infections acquired in the intensive care unit (AFI) are life-threating complications of critical illness. However, there is no consensus on antifungal prophylaxis in this setting. Multiple site decontamination is a well-studied prophylaxis against bacterial and fungal infections. Data on the effect of decontamination regimens on AFI are lacking. We hypothesised that multiple site decontamination could decrease the rate of AFI in mechanically ventilated patients.

METHODS

We conducted a pre/post observational study in 2 ICUs, on adult patients who required mechanical ventilation for >24 h. During the study period, multiple-site decontamination was added to standard of care. It consists of amphotericin B four times daily in the oropharynx and the gastric tube along with topical antibiotics, chlorhexidine body wash and nasal mupirocin.

RESULTS

In 870 patients, there were 27 AFI in 26 patients. Aspergillosis accounted for 20/143 of ventilator-associated pneumonia and candidemia for 7/75 of ICU-acquired bloodstream infections. There were 3/308 (1%) patients with AFI in the decontamination group and 23/562 (4%) in the standard-care group (p = 0.011). In a propensity-score matched analysis, there were 3/308 (1%) and 16/308 (5%) AFI in the decontamination group and the standard-care group respectively (p = 0.004) (3/308 vs 11/308 ventilator-associated pulmonary aspergillosis, respectively [p = 0.055] and 0/308 vs 6/308 candidemia, respectively [p = 0.037]).

CONCLUSION

Acquired fungal infection is a rare event, but accounts for a large proportion of ICU-acquired infections. Our study showed a preventive effect of decontamination against acquired fungal infection, especially candidemia.Take home messageAcquired fungal infection (AFI) incidence is close to 4% in mechanically ventilated patients without antifungal prophylaxis (3% for pulmonary aspergillosis and 1% for candidemia).Aspergillosis accounts for 14% of ventilator-associated pneumonia and candidemia for 9% of acquired bloodstream infections.Immunocompromised patients, those infected with SARS-COV 2 or influenza virus, males and patients admitted during the fall season are at higher risk of AFI.Mechanically ventilated patients receiving multiple site decontamination (MSD) have a lower risk of AFI.

Managing the Next Wave of Influenza and/or SARS-CoV-2 in the ICU—Practical Recommendations from an Expert Group for CAPA/IAPA Patients

The aim of this study was to establish practical recommendations for the diagnosis and treatment of influenza-associated invasive aspergillosis (IAPA) based on the available evidence and experience acquired in the management of patients with COVID-19-associated pulmonary aspergillosis (CAPA). The CAPA/IAPA expert group defined 14 areas in which recommendations would be made. To search for evidence, the PICO strategy was used for both CAPA and IAPA in PubMed, using MeSH terms in combination with free text. Based on the results, each expert developed recommendations for two to three areas that they presented to the rest of the group in various meetings in order to reach consensus. As results, the practical recommendations for the management of CAPA/IAPA patients have been grouped into 12 sections. These recommendations are presented for both entities in the following situations: when to suspect fungal infection; what diagnostic methods are useful to diagnose these two entities; what treatment is recommended; what to do in case of resistance; drug interactions or determination of antifungal levels; how to monitor treatment effectiveness; what action to take in the event of treatment failure; the implications of concomitant corticosteroid administration; indications for the combined use of antifungals; when to withdraw treatment; what to do in case of positive cultures for Aspergillus spp. in a patient with severe viral pneumonia or Aspergillus colonization; and how to position antifungal prophylaxis in these patients. Available evidence to support the practical management of CAPA/IAPA patients is very scarce. Accumulated experience acquired in the management of CAPA patients can be very useful for the management of IAPA patients. The expert group presents eminently practical recommendations for the management of CAPA/IAPA patients.

Clinical features and outcome of influenza pneumonia in critically-ill immunocompromised patients

Immunocompromised subjects are at risk of severe viral infections which may require intensive care unit (ICU) admission. Data on the outcome of influenza pneumonia in critically-ill immunocompromised subjects are limited. We conducted a single-center observational study. All subjects admitted to the ICU for influenza pneumonia between 2016 and 2020 were included. The main objective was to compare the clinical features and outcome of critically-ill subjects with flu according to their immune status. 137 subjects (age 60 years-old, 58.4% male) were included, of whom 58 (42.34%) were intubated during the ICU stay. Forty-three (31.4%) subjects were immunocompromised. Immunocompromised subjects had a higher Charlson comorbidity index. In contrast, severity scores and hypoxemia at ICU admission, and ventilatory support during ICU stay were similar between the 2 groups. There was no difference in the rate of co-infections and ventilator-associated pneumonia between the 2 groups. Among intubated subjects, 10 (23.26%) immunocompromised subjects developed severe acute respiratory distress syndrome compared to 13 (13.83%) non-immunocompromised (P = .218). ICU mortality was 13.97%, with mortality being 3-times higher in immunocompromised subjects (25.58% vs 8.6%, P = .015). On multivariable analysis, immunocompromised status, higher age and lower arterial oxygen partial pressure/fraction of inspired oxygen were associated with an increased ICU mortality. Immunocompromised subjects with severe influenza pneumonia were more likely to develop severe acute respiratory distress syndrome and had a 3-fold increase in ICU mortality compared to non-immunocompromised subjects. Such difference was not explained by an increased rate of co-infections or nosocomial pneumonia, suggesting that influenza virus was by itself responsible of a more severe form of pulmonary disease in immunocompromised subjects.

Diagnosis and Antifungal Prophylaxis for COVID-19 Associated Pulmonary Aspergillosis

The COVID-19 pandemic has redemonstrated the importance of the fungal-after-viral phenomenon, and the question of whether prophylaxis should be used to prevent COVID-19-associated pulmonary aspergillosis (CAPA). A distinct pathophysiology from invasive pulmonary aspergillosis (IPA), CAPA has an incidence that ranges from 5% to 30%, with significant mortality. The aim of this work was to describe the current diagnostic landscape of CAPA and review the existing literature on antifungal prophylaxis. A variety of definitions for CAPA have been described in the literature and the performance of the diagnostic tests for CAPA is limited, making diagnosis a challenge. There are only six studies that have investigated antifungal prophylaxis for CAPA. The two studied drugs have been posaconazole, either a liquid formulation via an oral gastric tube or an intravenous formulation, and inhaled amphotericin. While some studies have revealed promising results, they are limited by small sample sizes and bias inherent to retrospective studies. Additionally, as the COVID-19 pandemic changes and we see fewer intubated and critically ill patients, it will be more important to recognize these fungal-after-viral complications among non-critically ill, immunocompromised patients. Randomized controlled trials are needed to better understand the role of antifungal prophylaxis.

Liposomal amphotericin B—the future

Advances in medicine have led to a growing number of people with compromised or suppressed immune systems who are susceptible to invasive fungal infections. In particular, severe fungal infections are becoming increasingly common in ICUs, affecting people within and outside of traditional risk groups alike. This is exemplified by the emergence of severe viral pneumonia as a significant risk factor for invasive pulmonary aspergillosis, and the recognition of influenza-associated pulmonary aspergillosis and, more recently, COVID-19-associated pulmonary aspergillosis.

The treatment landscape for haematological malignancies has changed considerably in recent years, and some recently introduced targeted agents, such as ibrutinib, are increasing the risk of invasive fungal infections. Consideration must also be given to the risk of drug–drug interactions between mould-active azoles and small-molecule kinase inhibitors.

At the same time, infections caused by rare moulds and yeasts are increasing, and diagnosis continues to be challenging. There is growing concern about azole resistance among both moulds and yeasts, mandating continuous surveillance and personalized treatment strategies.

It is anticipated that the epidemiology of fungal infections will continue to change and that new populations will be at risk. Early diagnosis and appropriate treatment remain the most important predictors of survival, and broad-spectrum antifungal agents will become increasingly important. Liposomal amphotericin B will remain an essential therapeutic agent in the armamentarium needed to manage future challenges, given its broad antifungal spectrum, low level of acquired resistance and limited potential for drug–drug interactions.

The Changing Landscape of Invasive Fungal Infections in ICUs: A Need for Risk Stratification to Better Target Antifungal Drugs and the Threat of Resistance

The landscape of invasive candidiasis and invasive aspergillosis has changed dramatically in intensive care units over the past two decades. Today, we are faced with new risk factors such as the emergence of resistance, but are also equipped with new therapeutic strategies and diagnostic tools which are changing epidemiological data and diagnostic algorithms. Some common points need to be addressed: (i) the best way to use microbiological tools and to integrate their results in decisional algorithms; (ii) the need to find the optimum balance between under-diagnosis and overtreatment; (iii) and the need to decipher pathophysiology. In this short review, we will try to illustrate these points.

COVID-19 Syndemic: Convergence of COVID-19, Pulmonary Aspergillosis (CAPA), Pulmonary Tuberculosis, Type 2 Diabetes Mellitus, and Arterial Hypertension

Bacterial coinfections, which increase the severity of respiratory viral infections, are frequent causes of mortality in influenza pandemics but have not been well characterized in patients with Coronavirus disease 2019 (COVID-19). Moreover, the association of COVID-19 infection with pulmonary Mycobacterium tuberculosis disease (TB) and concurrent pulmonary fungal infection is not well known. The classification of patients with COVID-19-associated pulmonary aspergillosis (CAPA) using the current definitions for invasive fungal diseases has proven difficult. In this study, we aimed to provide information about three patients with underlying diseases ongoing with COVID-19 and co-infection with pulmonary TB, and with COVID-19-associated pulmonary aspergillosis (CAPA). At the time of hospital admission, each patient presented complications such as decompensated T2DM with diabetic ketoacidosis and/or hypertension. Findings of chest computed tomography and serum galactomannan by radioimmunoassay were useful for classifying them as possible CAPA. One of the three possible CAPA cases was fatal. These three cases are rare and are the first of their kind reported worldwide. The generation of reliable algorithms, early diagnosis, standardization of classification criteria, and the selection of specific and personalized treatments for COVID-19-associated opportunistic infections, including CAPA, are necessary to improve outcomes in these kinds of patients.

COVID-19-associated fungal infections

Coronavirus disease 2019 (COVID-19)-associated invasive fungal infections are an important complication in a substantial number of critically ill, hospitalized patients with COVID-19. Three groups of fungal pathogens cause co-infections in COVID-19: Aspergillus, Mucorales and Candida species, including Candida auris. Here we review the incidence of COVID-19-associated invasive fungal infections caused by these fungi in low-, middle- and high-income countries. By evaluating the epidemiology, clinical risk factors, predisposing features of the host environment and immunological mechanisms that underlie the pathogenesis of these co-infections, we set the scene for future research and development of clinical guidance.

Hoenigl and colleagues review the epidemiology, immunology and clinical risk factors contributing to COVID-19-associated fungal infections.

Nebulized Amphotericin B in Mechanically Ventilated COVID-19 Patients to Prevent Invasive Pulmonary Aspergillosis: A Retrospective Cohort Study

Despite high mortality rates of COVID-19-associated pulmonary aspergillosis (CAPA) in the ICU, antifungal prophylaxis remains a subject of debate. We initiated nebulized conventional amphotericin B (c-AmB) as antifungal prophylaxis in COVID-19 patients on invasive mechanical ventilation (IMV).

OBJECTIVES

To assess the CAPA incidence in COVID-19 patients on IMV treated with and without nebulized c-AmB as antifungal prophylaxis.

DESIGN SETTING AND PARTICIPANTS

Retrospective cohort study of consecutive COVID-19 patients admitted to our adult 17-bed ICU in a university-affiliated general hospital in Ede, The Netherlands, between January 25, 2021, and July 9, 2021. Patients not requiring IMV or transferred from or to another ICU were excluded. From April 9, 2021, daily nebulized amphotericin B in all patients on IMV was initiated.

MAIN OUTCOMES AND MEASURES

Bronchoscopy with bronchoalveolar lavage (BAL) was performed in case of positive cultures for Aspergillus from the respiratory tract and/or unexplained respiratory deterioration. Incidence of probable and proven CAPA was compared between patients treated with and without nebulized antifungal prophylaxis using Pearson chi-square test.

RESULTS

A total of 39 intubated COVID-19 patients could be analyzed, of which 16 were treated with antifungal prophylaxis and 23 were not. Twenty-six patients underwent bronchoscopy with BAL. In patients treated with antifungal prophylaxis, the incidence of probable/proven CAPA was significantly lower when compared with no antifungal prophylaxis (27% vs 67%; p = 0.047). Incidence of tracheobronchial lesions and positive Aspergillus cultures and BAL-galactomannan was significantly lower in patients treated with antifungal prophylaxis (9% vs 47%; p = 0.040, 9% vs 53%; p = 0.044, and 20% vs 60%; p = 0.047, respectively). No treatment-related adverse events and no case of proven CAPA were encountered in patients receiving antifungal prophylaxis.

CONCLUSIONS AND RELEVANCE

Nebulization of c-AmB in critically ill COVID-19 patients on IMV is safe and may be considered as antifungal prophylaxis to prevent CAPA. However, a randomized controlled trial to confirm this is warranted.

Mechanistic Basis of Super-Infection: Influenza-Associated Invasive Pulmonary Aspergillosis

Influenza infection is a risk factor for invasive pulmonary aspergillosis in both immunocompetent and immunocompromised hosts. The purpose of this review is to highlight the epidemiology of influenza-associated invasive pulmonary aspergillosis and the mechanistic studies that have been performed to delineate how influenza increases susceptibility to this invasive fungal infection.

Exposure to intravenous posaconazole in critically ill patients with influenza: a pharmacokinetic analysis of the POSA-FLU study

BACKGROUND

Data on posaconazole in the critically ill are scarce. In the POSA-FLU study we examined the prevention of influenza-associated pulmonary aspergillosis with posaconazole in this population.

METHODS

In this observational sub-study, we performed a pharmacokinetic analysis, including protein binding and target attainment (TA). Blood samples were collected over a 24h-dosing interval on both an early (day 2 or 3) and a later (≥ day 4) treatment day.

RESULTS

TA was shown for AUC_0-24 and C_min prophylaxis but not for C_min treatment. Moreover, a saturable protein binding with a significant, positive relationship between albumin concentrations and the maximum binding capacity was observed.

CONCLUSIONS

Our analysis indicates that posaconazole may be a suitable drug to further investigate for prophylaxis, as TA for prophylaxis was reached. Exposure targets for treatment were insufficiently attained in this population.

Invasive Respiratory Fungal Infections in COVID-19 Critically Ill Patients

Patients with coronavirus disease 19 (COVID-19) admitted to the intensive care unit (ICU) often develop respiratory fungal infections. The most frequent diseases are the COVID-19 associated pulmonary aspergillosis (CAPA), COVID-19 associated pulmonary mucormycosis (CAPM) and the Pneumocystis jirovecii pneumonia (PCP), the latter mostly found in patients with both COVID-19 and underlying HIV infection. Furthermore, co-infections due to less common mold pathogens have been also described. Respiratory fungal infections in critically ill patients are promoted by multiple risk factors, including epithelial damage caused by COVID-19 infection, mechanical ventilation and immunosuppression, mainly induced by corticosteroids and immunomodulators. In COVID-19 patients, a correct discrimination between fungal colonization and infection is challenging, further hampered by sampling difficulties and by the low reliability of diagnostic approaches, frequently needing an integration of clinical, radiological and microbiological features. Several antifungal drugs are currently available, but the development of new molecules with reduced toxicity, less drug-interactions and potentially active on difficult to treat strains, is highly warranted. Finally, the role of prophylaxis in certain COVID-19 populations is still controversial and must be further investigated.

Invasive aspergillosis in coronavirus disease 2019: a practical approach for clinicians

PURPOSE OF REVIEW

Invasive pulmonary aspergillosis (IPA) can affect patients with severe coronavirus disease 2019 (COVID-19), but many questions remain open about its very variable incidence across the world, the actual link between the viral infection and the fungal superinfection, the significance of Aspergillus recovery in a respiratory sample, and the management of such cases. This review addresses these questions and aims at providing some clues for the practical diagnostic and therapeutic approaches of COVID-19-associated pulmonary aspergillosis (CAPA) in a clinical perspective.

RECENT FINDINGS

Definitions have been proposed for possible/probable/proven CAPA, but distinction between colonization and invasive fungal infection is difficult and not possible in most cases in the absence of histopathological proof or positive galactomannan in serum. Most importantly, the recovery of an Aspergillus by a direct (culture, PCR) or indirect (galactomannan) test in a respiratory sample is an indicator of worse outcome, which justifies a screening for early detection and initiation of preemptive antifungal therapy in such cases.

SUMMARY

The COVID-19 pandemic has increased our awareness of IPA among ICU patients. Although current recommendations are mainly based on experts' opinions, prospective studies are needed to get more evidence-based support for the diagnostic approach and management of CAPA.

ESCMID COVID-19 living guidelines: drug treatment and clinical management

SCOPE

In January 2021, the ESCMID Executive Committee decided to launch a new initiative to develop ESCMID guidelines on several COVID-19-related issues, including treatment of COVID-19.

METHODS

An ESCMID COVID-19 guidelines task force was established by the ESCMID Executive Committee. A small group was established, half appointed by the chair, and the remaining selected with an open call. Each panel met virtually once a week. For all decisions, a simple majority vote was used. A long list of clinical questions using the PICO (population, intervention, comparison, outcome) format was developed at the beginning of the process. For each PICO, two panel members performed a literature search with a third panellist involved in case of inconsistent results. Voting was based on the GRADE approach.

QUESTIONS ADDRESSED BY THE GUIDELINE AND RECOMMENDATIONS

A synthesis of the available evidence and recommendations is provided for each of the 15 PICOs, which cover use of hydroxychloroquine, bamlanivimab alone or in combination with etesevimab, casirivimab combined with imdevimab, ivermectin, azithromycin and empirical antibiotics, colchicine, corticosteroids, convalescent plasma, favipiravir, remdesivir, tocilizumab and interferon β-1a, as well as the utility of antifungal prophylaxis and enoxaparin. In general, the panel recommended against the use of hydroxychloroquine, ivermectin, azithromycin, colchicine and interferon β-1a. Conditional recommendations were given for the use of monoclonal antibodies in high-risk outpatients with mild-moderate COVID-19, and remdesivir. There was insufficient evidence to make a recommendation for use of favipiravir and antifungal prophylaxis, and it was recommended that antibiotics should not be routinely prescribed in patients with COVID-19 unless bacterial coinfection or secondary infection is suspected or confirmed. Tocilizumab and corticosteroids were recommended for treatment of severe COVID-19 but not in outpatients with non-severe COVID-19.

SCOPE

The aim of the present guidance is to provide evidence-based recommendations for management of adults with coronavirus disease 2019 (COVID-19). More specifically, the goal is to aid clinicians managing patients with COVID-19 at various levels of severity including outpatients, hospitalized patients, and those admitted to intensive care unit. Considering the composition of the panel, mostly clinical microbiologists or infectious disease specialists with no pulmonology or intensive care background, we focus only on pharmacological treatment and do not give recommendations on oxygen supplement/support. Similarly, as no paediatricians were included in the panel; the recommendations are only for adult patients with COVID-19. Considering the current literature, no guidance was given for special populations such as the immunocompromised.

Management of Severe Influenza

Influenza infection causes severe illness in 3 to 5 million people annually, with up to an estimated 650,000 deaths per annum. As such, it represents an ongoing burden to health care systems and human health. Severe acute respiratory infection can occur, resulting in respiratory failure requiring intensive care support. Herein we discuss diagnostic approaches, including development of CLIA-waived point of care tests that allow rapid diagnosis and treatment of influenza. Bacterial and fungal coinfections in severe influenza pneumonia are associated with worse outcomes, and we summarize the approach and treatment options for diagnosis and treatment of bacterial and Aspergillus coinfection. We discuss the available drug options for the treatment of severe influenza, and treatments which are no longer supported by the evidence base. Finally, we describe the supportive management and ventilatory approach to patients with respiratory failure as a result of severe influenza in the intensive care unit.

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.

Incidence, risk factors and mortality of invasive pulmonary aspergillosis in patients with influenza: A systematic review and meta-analysis

Background

An increasing number of cases of invasive pulmonary aspergillosis (IPA) complicating influenza have been described. We performed a meta‐analysis to estimate the incidence, risk factors and outcomes of IPA in patients with influenza.

Methods

A systematic search was conducted in the PubMed, EMBASE and Cochrane Library databases from their inception to 31 August 2021 for eligible studies. Data on the incidence and risk factors of and mortality due to IPA in influenza patients were pooled using a random‐effects model. Sensitivity analyses restricted to severe influenza requiring intensive care unit (ICU) support and multiple subgroup analyses were performed.

Results

Fourteen studies involving 6024 hospitalised patients with influenza were included. IPA was estimated to occur in 10% of influenza patients, with a mortality rate of 52%. Similar incidence (11%) and mortality (54%) estimates for IPA were observed in the sensitivity analysis including severe cases requiring ICU support. Subgroup analysis by geographical location showed a similar IPA rate between European (10%) and non‐European (11%) studies. The IPA rate in the subset of nine studies using the modified AspICU criteria was 13%. Most subgroup analyses showed ≥50% mortality in IPA patients. Several predictors for IPA susceptibility were identified, including male sex, smoking history, chronic lung disease, influenza A (H1N1), severe conditions requiring supportive therapy, corticosteroid use before admission, solid organ transplant and haematological malignancy.

Conclusions

The IPA is common in individuals with severe influenza, and the prognosis is particularly poor. Influenza patients, especially those with high‐risk factors, should be thoroughly screened for IPA.

Early Identification and Diagnostic Approach in Acute Respiratory Distress Syndrome (ARDS)

Acute respiratory distress syndrome (ARDS) is a life-threatening condition defined by the acute onset of severe hypoxemia with bilateral pulmonary infiltrates, in the absence of a predominant cardiac involvement. Whereas the current Berlin definition was proposed in 2012 and mainly focused on intubated patients under invasive mechanical ventilation, the recent COVID-19 pandemic has highlighted the need for a more comprehensive definition of ARDS including patients treated with noninvasive oxygenation strategies, especially high-flow nasal oxygen therapy, and fulfilling all other diagnostic criteria. Early identification of ARDS in patients breathing spontaneously may allow assessment of earlier initiation of pharmacological and non-pharmacological treatments. In the same way, accurate identification of the ARDS etiology is obviously of paramount importance for early initiation of adequate treatment. The precise underlying etiological diagnostic (bacterial, viral, fungal, immune, malignant, drug-induced, etc.) as well as the diagnostic approach have been understudied in the literature. To date, no clinical practice guidelines have recommended structured diagnostic work-up in ARDS patients. In addition to lung-protective ventilation with the aim of preventing worsening lung injury, specific treatment of the underlying cause has a central role to improve outcomes. In this review, we discuss early identification of ARDS in non-intubated patients breathing spontaneously and propose a structured diagnosis work-up.