Influenza-associated Aspergillosis in Critically Ill Patients

[Nosocomial pneumonia]

Nosocomial pneumonia is defined as pneumonia occurring ≥ 48 h after hospital admission in a patient without severe immunosuppression. It can occur in spontaneously breathing patients or with noninvasive ventilation (NIV) and mechanically ventilated patients. In patients with suspected ventilator-associated pneumonia (VAP) (semi)quantitative cultures of tracheobronchial aspirates or bronchoalveolar lavage fluid should be perfomed. The initial empirical antimicrobial treatment is determined by the risk for multidrug-resistant pathogens (MDRP). The advantage of combination treatment increases with the prevalence of MDRPs. The antibiotic treatment should be adapted when the microbiological results are available. After 72 h a standardized re-evaluation including the response to treatment and also checking of the suspected diagnosis of pneumonia in a structured form is mandatory. Treatment failure can occur as a primary or secondary failure and in the case of primary progression necessitates another comprehensive diagnostic work-up before any further antibiotic treatment.

Use of nebulized liposomal amphotericin B and posaconazole as antifungal prophylaxis in patients with severe SARS-CoV2 infection in intensive care unit

PURPOSE

COVID-19 associated pulmonary aspergillosis (CAPA) is common and linked with high fatality rates. To assess the impact on the incidence and outcome of CAPA of an antifungal prophylaxis (AFP) we compared two cohorts of COVID-19 patients admitted to intensive care units (ICU) in Brescia, Italy, from January to August 2021.

METHODS

The study cohort included all mechanically ventilated patients observed between April 2021 and August 2021 with SARS-CoV-2-pneumonia, who received AFP with oral posaconazole (200 mg every 6 h) and nebulized liposomal amphotericin B (50 mg every 2 weeks) from ICU admission to 7 days after discharge or, if applicable, until tracheostomy removal. The control cohort included COVID-19 patients admitted to the same ICU between January and March 2021 who did not receive any AFP. Subjects with CAPA at ICU admission were excluded.

RESULTS

We included 270 patients, of whom 64 (23.7%) received AFP. In patients in the study group, CAPA-related mortality was significantly reduced (29% vs. 48% p = 0.04), as well as the incidence of CAPA (3.1% vs 12.1%, p = 0.03). Patients who developed CAPA were older (mean of 70-y-old vs 63-y-old, p < 0.001). One subject discontinued posaconazole due to an adverse reaction. Among the 46 patients who received it, only one patient reached an effective plasma concentration of posaconazole.

CONCLUSION

AFP was associated with reduced incidence and mortality from CAPA and was well tolerated in patients with severe COVID-19. Posaconazole concentrations below the efficacy threshold in almost all patients may be attributable to drug interactions and prompt further studies to define its clinical significance.

Clinical significance of lower respiratory tract culture within 48 h of admission in patients with viral pneumonia: an observational study

BACKGROUND

The aim of this retrospective study was to examine the risk factors of positive lower respiratory tract cultures and to investigate whether nosocomial infections are common in patients with positive lower respiratory tract cultures.

METHODS

We enrolled 86 patients diagnosed with influenza A-related critical illness who were treated at Fuzhou Pulmonary Hospital of Fujian in China between 1st October 2013 and 31st March 2019. The of admission were used to divide the enrolled patients into two groups. Sputum and bronchoalveolar lavage fluid specimens were collected within 48 h after admission for culture. All samples were cultured immediately after sampling. Nosocomial infections are defined as any symptom or sign of pulmonary infiltration, confirmed by X-ray, after 5 days of admission and positive results from one or more cultures.

RESULTS

The average age of this cohort was (54.13 ± 16.52) years. Based on the culture results, Staphylococcus aureus and Candida albicans had the highest positive rates (3.40% (3/86) and 20.90% (18/86), respectively). In patients with positive lower respiratory tract cultures, the incidence of nosocomial infection was 73.30% (22/30) five days after admission. However, the incidence of nosocomial infection was lower (42.80%, 24/56) in patients with negative lower respiratory tract cultures. Hemoptysis, systolic pressure at admission, and blood urea nitrogen level at admission were all independent risk factors for positive lower respiratory tract cultures within 48 h of admission.

CONCLUSION

Our data showed that a significant proportion of patients with pneumonia exhibited co-infections with bacteria or fungi within five days of hospital admission. Hemoptysis, systolic pressure, and blood urea nitrogen levels at admission emerged as the key risk factors. These findings underscore the necessity of closely monitoring patients with influenza infection, particularly for positive bacterial or fungal cultures within the initial 48 h of admission.

Optimizing Antifungal Treatment Strategies to Prevent Invasive Pulmonary Aspergillosis Infection-Related Deaths in Intensive Care Unit Patients: The Need for Standardization of Research Definitions

The clinical spectrum of invasive pulmonary aspergillosis (IPA) has expanded in recent decades. A large group of patients admitted to intensive care units (ICU) is indeed susceptible to the development of IPA. Although timely diagnosis and antifungal therapy of IPA in this expanding population is crucial to prevent IPA-related deaths, the magnitude of the favorable prognostic impact of antifungal therapy is difficult to measure precisely. In our opinion, the development of standardized research definitions could have favorable implications for further improving our ability both to measure the favorable effect of antifungal treatment and to prevent IPA-related death in ICU patients.

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.

Aspergillosis in Critically Ill Patients with and Without COVID-19 in a Tertiary Hospital in Southern Brazil

The impact of invasive pulmonary aspergillosis (IPA) on non-neutropenic critically ill patients in intensive care units (ICU) has been demonstrated in recent decades. Furthermore, after the start of the COVID-19 pandemic, COVID-19 associated with pulmonary aspergillosis (CAPA) has become a major concern in ICUs. However, epidemiological data from different regions are scarce. We evaluated the prevalence and clinical-epidemiological data of IPA in patients with COVID-19 requiring mechanical ventilation (MV) in the ICU ("severe COVID-19") and non-COVID ICU patients in MV of a tertiary hospital in the southern region of Brazil. Eighty-seven patients admitted between June 2020 and August 2022 were included; 31 with severe COVID-19. For the diagnosis of IPA or CAPA, algorithms including host factors and mycological criteria (positive culture for Aspergillus spp., immunoassay for galactomannan detection, and/or qPCR) were utilized. The overall incidence of IPA and CAPA in our ICU was 73 cases/1000 ICU hospitalizations. Aspergillosis occurred in 13% (4/31) of the COVID-19 patients, and in 16% (9/56) of the critically ill patients without COVID-19, with mortality rates of 75% (3/4) and 67% (6/9), respectively. Our results highlight the need for physicians enrolled in ICU care to be aware of aspergillosis and for more access of the patients to sensitive and robust diagnostic tests by biomarkers detection.

The respiratory syncytial virus vaccines are here: Implications for solid organ transplantation

In 2023, the Food and Drug Administration approved 2 recombinant subunit respiratory syncytial virus (RSV) vaccines based on prefusion RSV F glycoproteins for the prevention of RSV-associated lower respiratory tract disease. These vaccines were subsequently recommended for individuals ≥60 years of age using shared clinical decision-making by the Center for Disease Control and Prevention's Advisory Committee on Immunization Practices. The development, deployment, and uptake of respiratory virus vaccines are of particular importance for solid organ recipients who are at higher risk of infectious complications and poor clinical outcomes, including from RSV-associated lower respiratory tract disease, compared to patients without immunocompromise. This review aims to summarize what is currently known about the burden of RSV disease in solid organ transplantation, to describe the currently available tools to mitigate the risk, and to highlight considerations regarding the implementation of these vaccines before and after transplantation. We also explore areas of unmet need for organ transplant recipients including questions of RSV vaccine effectiveness and safety, inequities in disease and vaccine access based on race and socioeconomic status, and expansion of coverage to immunocompromised individuals below the age of 60 years.

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 Fungal Diseases in Adult Patients in Intensive Care Unit (FUNDICU): 2024 consensus definitions from ESGCIP, EFISG, ESICM, ECMM, MSGERC, ISAC, and ISHAM

PURPOSE

The aim of this document was to develop standardized research definitions of invasive fungal diseases (IFD) in non-neutropenic, adult patients without classical host factors for IFD, admitted to intensive care units (ICUs).

METHODS

After a systematic assessment of the diagnostic performance for IFD in the target population of already existing definitions and laboratory tests, consensus definitions were developed by a panel of experts using the RAND/UCLA appropriateness method.

RESULTS

Standardized research definitions were developed for proven invasive candidiasis, probable deep-seated candidiasis, proven invasive aspergillosis, probable invasive pulmonary aspergillosis, and probable tracheobronchial aspergillosis. The limited evidence on the performance of existing definitions and laboratory tests for the diagnosis of IFD other than candidiasis and aspergillosis precluded the development of dedicated definitions, at least pending further data. The standardized definitions provided in the present document are aimed to speed-up the design, and increase the feasibility, of future comparative research studies.

Comparison of influenza- and COVID-19-associated pulmonary aspergillosis in China

PURPOSE

We conducted a monocentric retrospective study using the latest definitions to compare the demographic, clinical, and biological characteristics of influenza-associated pulmonary aspergillosis (IAPA) and COVID-19-associated pulmonary aspergillosis (CAPA).

METHODS

The study retrospectively enrolled 180 patients, including 70 influenza/IPA patients (with positive influenza A/B and Aspergillus) and 110 COVID-19/IPA patients (with positive SARS-CoV-2 and Aspergillus). Among them, 42 (60%) and 30 (27.3%) patients fulfilled the definitions of IAPA and CAPA, respectively.

RESULTS

The CAPA patients had significantly higher in-hospital mortality (13/31, 41.9%) than IAPA patients (8/42, 19%) with a P-value of 0.033. Kaplan-Meier survival curve also showed significantly higher 30-day mortality for CAPA patients (P = 0.025). Additionally, the CAPA patients were older, though insignificantly, than IAPA patients (70 (60-80) vs. 62 (52-72), P = 0.075). A lower percentage of chronic pulmonary disease (12.9 vs. 40.5%, P = 0.01) but higher corticosteroids use 7 days before and after ICU admission (22.6% vs. 0%, P = 0.002) were found in CAPA patients. Notably, there were no significant differences in the percentage of ICU admission or ICU mortality between the two groups. In addition, the time from observation to Aspergillus diagnosis was significantly longer in CAPA patients than in IAPA patients (7 (2-13) vs. 0 (0-4.5), P = 0.048).

CONCLUSION

Patients infected with SARS-CoV-2 and Aspergillus during the concentrated outbreak of COVID-19 in China had generally higher in-hospital mortality but a lower percentage of chronic pulmonary disease than those infected with influenza and Aspergillus. For influenza-infected patients who require hospitalization, close attention should be paid to the risk of invasive aspergillosis upfront.

The influenza A virus promotes fungal growth of Aspergillus fumigatus via direct interaction in vitro

Seasonal influenza A virus (IAV) infections still pose a major burden for public health worldwide. Severe disease progression or even death is often related to superinfections of the virus and a secondary bacterial pathogen. However, fungi, especially Aspergillus fumigatus, are also frequently diagnosed during IAV infection. Although, clinical studies have reported the severity of influenza-associated pulmonary aspergillosis, the molecular mechanisms underlying this type of disease are poorly understood. Here, a new in vitro model is introduced that allows the investigation of complex pathogen-host and pathogen-pathogen interactions during coinfection of lung epithelial cells with IAV and A. fumigatus. Our data reveal a reduced IAV load and IAV-induced cytokine and chemokine expression in the presence of A. fumigatus. At the same time, IAV infection promotes the growth of A. fumigatus. Even in the absence of the human host cell, purified IAV particles are able to induce hyphal growth, due to a direct interaction of the virus particles with the fungal surface. Thus, our study gives first insights into the complex interplay between IAV, A. fumigatus and the host cell as well as the two pathogens alone.

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/.

Influenza-associated invasive aspergillosis in patients admitted to the intensive care unit in Sweden: a prospective multicentre cohort study

BACKGROUND

The purpose of this study was to prospectively investigate the incidence of influenza-associated pulmonary aspergillosis (IAPA) in influenza patients admitted to intensive care units in Sweden.

METHODS

The study included consecutive adult patients with PCR-verified influenza A or B in 12 Swedish intensive care units (ICUs) over four influenza seasons (2019-2023). Patients were screened using serum galactomannan and β-d-glucan tests and fungal culture of a respiratory sample at inclusion and weekly during the ICU stay. Bronchoalveolar lavage was performed if clinically feasible. IAPA was classified according to recently proposed case definitions.

RESULTS

The cohort included 55 patients; 42% were female, and the median age was 59 (IQR 48-71) years. All patients had at least one galactomannan test, β-d-glucan test and respiratory culture performed. Bronchoalveolar lavage was performed in 24 (44%) of the patients. Five (9%, 95% CI 3.8% - 20.4%) patients were classified as probable IAPA, of which four lacked classical risk factors. The overall ICU mortality was significantly higher among IAPA patients than non-IAPA patients (60% vs 8%, p = 0.01).

CONCLUSIONS

The study represents the first prospective investigation of IAPA incidence. The 9% incidence of IAPA confirms the increased risk of invasive pulmonary aspergillosis among influenza patients admitted to the ICU. Therefore, it appears reasonable to implement a screening protocol for the early diagnosis and treatment of IAPA in influenza patients receiving intensive care.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04172610, registered November 21, 2019.

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.

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.

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.

A Tale of Two Hospitals: Comparing CAPA Infections in Two ICUs During the Spanish Fourth Pandemic Wave

PURPOSE

COVID-19 associated pulmonary aspergillosis (CAPA) is a new clinical entity linked to SARS-CoV-2 infection that is causing a rise on the risk of complications and mortality, particularly in critical patients.

METHODS

We compared diagnostic and clinical features in two cohorts of patients with severe COVID-19 admitted in the intensive care units (ICU) of two different hospitals in Madrid, Spain, between February and June 2021. Clinical and microbiological relevant aspects for CAPA diagnosis were collected for further classification. CAPA was classified as colonization, possible, probable, proven, and tracheobronchial aspergillosis according to the ECMM/ISHAM consensus, with some modifications to consider tracheobronchial aspirate as sample comparable to non-bronchoscopic lavages (NBL).

RESULTS

56 patients admitted in HULP (Hospital Universitario La Paz) ICU and 61 patients admitted in HEEIZ (Hospital de Emergencias Isabel Zendal) ICU had clinical suspicion of invasive fungal disease in the context of COVID-19 infection. Cultures were positive for Aspergillus spp. in 32 patients. According to 2020 European Confederation of Medical Mycology and the International Society for Human and Animal Mycology (ECMM/ISHAM) consensus, 11 patients were diagnosed with possible CAPA and 10 patients with probable CAPA. Global incidence for CAPA was 6.3%. Global median days between ICU admission and diagnosis was 14 day. Aspergillus fumigatus complex was the main isolated species. Antifungal therapy was used in 75% of patients with CAPA suspicion, with inter-hospital differences in the administered antifungals. Global overall mortality rate for CAPA patients was 66.6% (14/21). All-cause mortality in non-CAPA cohorts were of 26.3% in HULP group (34/129) and 56.8% (104/183) in HEEIZ group.

CONCLUSIONS

There were no significant differences in incidence between the two hospitals, and differences in antifungal therapy did not correlate with differences in mortality, reflecting that both first-line azoles and Amphotericin B could be effective in treating CAPA infections, according to the current guideline indications.

Early Detection of Aspergillus Species in Lower Respiratory Tract is Associated with Higher Mortality in Viral Community-Acquired Pneumonia: A Multicenter Prospective Cohort Study in China

PURPOSE

Community-acquired pneumonia (CAP) is a leading cause of adult mortality worldwide and poses a significant global burden. Previous studies have indicated a tendency for viral pneumonia, particularly severe influenza virus pneumonia, to be complicated by Aspergillus superinfection. However, the clinical features and prognostic implications of Aspergillus detection in early-onset viral CAP remain unclear.

METHODS

We conducted a prospective multicenter observational cohort study in China involving CAP patients. Adult patients with CAP from six hospitals were enrolled between January 2017 and October 2018. Within 72 h of admission, lower respiratory tract specimens, including sputum and alveolar lavage fluid, were collected. Comprehensive pathogenic testing, utilizing molecular biology techniques, was performed on the collected specimens, encompassing bacteria, atypical pathogens, viruses, and fungi. Patient clinical data were collected through a unified electronic medical record website system.

RESULTS

A total of 382 adult CAP patients were included in the study. The viral detection rate was 38% (145/382), with Aspergillus identified in 11.0% (16/145) of viral CAP cases. Mortality among Aspergillus-positive patients was significantly higher (25%, 4/16) compared to Aspergillus-negative patients (5.4%, 7/129) in viral CAP (P = 0.021). Multivariable logistic regression models demonstrated that the presence of Aspergillus at admission might increase the mortality risk in viral CAP [OR (95%CI) = 7.34 (0.92-58.65), P = 0.06]. Furthermore, Aspergillus-positive patients exhibited a significantly lower lymphocyte count than Aspergillus-negative patients (P = 0.047).

CONCLUSION

Positive detection of Aspergillus in lower respiratory tract specimens might be associated with higher mortality in early-onset viral CAP.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT03093220. Registered retrospectively on 28 March 2017.

COVID-19-Associated Pulmonary Aspergillosis in Intensive Care Unit Patients from Poland

Coronavirus disease 2019 (COVID-19) has been shown to be a favoring factor for aspergillosis, especially in a severe course requiring admission to the intensive care unit (ICU). The aim of the study was to assess the morbidity of CAPA among ICU patients in Poland and to analyze applied diagnostic and therapeutic procedures. Medical documentation of patients hospitalized at the temporary COVID-19 dedicated ICU of the University Hospital in Krakow, Poland, from May 2021 to January 2022 was analyzed. In the analyzed period, 17 cases of CAPA were reported with an incidence density rate of 9 per 10 000 patient days and an incidence rate of 1%. Aspergillus fumigatus and Aspergillus niger were isolated from lower respiratory samples. Antifungal therapy was administered to 9 patients (52.9%). Seven patients (77.8%) received voriconazole. The CAPA fatality case rate was 76.5%. The results of the study indicate the need to increase the awareness of medical staff about the possibility of fungal co-infections in ICU patients with COVID-19 and to use the available diagnostic and therapeutic tools more effectively.

Phenotypic Array for Identification and Screening of Antifungals against Aspergillus Isolates from Respiratory Infections in KwaZulu Natal, South Africa

The rapid emergence of invasive fungal infections correlates with the increasing population of immunocompromised individuals, with many cases leading to death. The progressive increase in the incidence of Aspergillus isolates is even more severe due to the clinical challenges in treating invasive infections in immunocompromised patients with respiratory conditions. Rapid detection and diagnosis are needed to reduce mortality in individuals with invasive aspergillosis-related infections and thus efficient identification impacts clinical success. The phenotypic array method was compared to conventional morphology and molecular identification on thirty-six Aspergillus species isolated from patients with respiratory infections at the Inkosi Albert Luthuli Hospital in Kwa-Zulu Natal. In addition, an antimicrobial array was also carried out to screen for possible novel antimicrobial compounds for treatment. Although traditional morphological techniques are useful, genetic identification was the most reliable, assigning 26 to Aspergillus fumigatus species, 8 Aspergillus niger, and 2 Aspergillus flavus including cryptic species of A. niger, A. tubingensis and A. welwitschiae. The phenotypic array technique was only able to identify isolates up to the genus level due to a lack of adequate reference clinical species in the database. However, this technique proved crucial in assessing a wide range of possible antimicrobial options after these isolates exhibited some resistance to azoles. Antifungal profiles of the thirty-six isolates on the routine azole voriconazole showed a resistance of 6%, with 61% having moderate susceptibility. All isolates resistant to the salvage therapy drug, posaconazole pose a serious concern. Significantly, A. niger was the only species resistant (25%) to voriconazole and has recently been reported as the species isolated from patients with COVID-19-associated pulmonary aspergillosis (CAPA). Phenotypic microarray showed that 83% of the isolates were susceptible to the 24 new compounds and novel compounds were identified for potentially effective combination treatment of fungal infections. This study also reports the first TR34/98 mutation in Aspergillus clinical isolates which is located in the cyp51A gene.

Invasive Pulmonary Aspergillosis in Coronavirus Disease 2019 Patients Lights and Shadows in the Current Landscape

Invasive pulmonary aspergillosis (IPA) presents a known risk to critically ill patients with SARS-CoV-2; quantifying the global burden of IPA in SARS-CoV-2 is extremely challenging. The true incidence of COVID-19-associated pulmonary aspergillosis (CAPA) and the impact on mortality is difficult to define because of indiscriminate clinical signs, low culture sensitivity and specificity and variability in clinical practice between centers. While positive cultures of upper airway samples are considered indicative for the diagnosis of probable CAPA, conventional microscopic examination and qualitative culture of respiratory tract samples have quite low sensitivity and specificity. Thus, the diagnosis should be confirmed with serum and BAL GM test or positive BAL culture to mitigate the risk of overdiagnosis and over-treatment. Bronchoscopy has a limited role in these patients and should only be considered when diagnosis confirmation would significantly change clinical management. Varying diagnostic performance, availability, and time-to-results turnaround time are important limitations of currently approved biomarkers and molecular assays for the diagnosis of IA. The use of CT scans for diagnostic purposes is controversial due to practical concerns and the complex character of lesions presented in SARS-CoV-2 patients. The key objective of management is to improve survival by avoiding misdiagnosis and by initiating early, targeted antifungal treatment. The main factors that should be considered upon selection of treatment options include the severity of the infection, concomitant renal or hepatic injury, possible drug interactions, requirement for therapeutic drug monitoring, and cost of therapy. The optimal duration of antifungal therapy for CAPA is still under debate.

Development of a Corticosteroid-Immunosuppressed Mouse Model to Study the Pathogenesis and Therapy of Influenza-Associated Pulmonary Aspergillosis

Influenza-associated pulmonary aspergillosis (IAPA) is a feared complication in patients with influenza tracheobronchitis, especially those receiving corticosteroids. Herein, we established a novel IAPA mouse model with low-inoculum Aspergillus infection and compared outcomes in mice with and without cortisone acetate (CA) immunosuppression. CA was an independent predictor of increased morbidity/mortality in mice with IAPA. Early antifungal treatment with liposomal amphotericin B was pivotal to improve IAPA outcomes in CA-immunosuppressed mice, even after prior antiviral therapy with oseltamivir. In summary, our model recapitulates key clinical features of IAPA and provides a robust preclinical platform to study the pathogenesis and treatment of IAPA.

Infections after organ transplantation and immune response

Organ transplantation has provided another chance of survival for end-stage organ failure patients. Yet, transplant rejection is still a main challenging factor. Immunosuppressive drugs have been used to avoid rejection and suppress the immune response against allografts. Thus, immunosuppressants increase the risk of infection in immunocompromised organ transplant recipients. The infection risk reflects the relationship between the nature and severity of immunosuppression and infectious diseases. Furthermore, immunosuppressants show an immunological impact on the genetics of innate and adaptive immune responses. This effect usually reactivates the post-transplant infection in the donor and recipient tissues since T-cell activation has a substantial role in allograft rejection. Meanwhile, different infections have been found to activate the T-cells into CD₄⁺ helper T-cell subset and CD₈⁺ cytotoxic T-lymphocyte that affect the infection and the allograft. Therefore, the best management and preventive strategies of immunosuppression, antimicrobial prophylaxis, and intensive medical care are required for successful organ transplantation. This review addresses the activation of immune responses against different infections in immunocompromised individuals after organ transplantation.

Invasive Aspergillosis and the Impact of Azole-resistance

Purpose of Review

IA (invasive aspergillosis) caused by azole-resistant strains has been associated with higher clinical burden and mortality rates. We review the current epidemiology, diagnostic, and therapeutic strategies of this clinical entity, with a special focus on patients with hematologic malignancies.

Recent Findings

There is an increase of azole resistance in Aspergillus spp. worldwide, probably due to environmental pressure and the increase of long-term azole prophylaxis and treatment in immunocompromised patients (e.g., in hematopoietic stem cell transplant recipients). The therapeutic approaches are challenging, due to multidrug-resistant strains, drug interactions, side effects, and patient-related conditions.

Summary

Rapid recognition of resistant Aspergillus spp. strains is fundamental to initiate an appropriate antifungal regimen, above all for allogeneic hematopoietic cell transplantation recipients. Clearly, more studies are needed in order to better understand the resistance mechanisms and optimize the diagnostic methods to identify Aspergillus spp. resistance to the existing antifungal agents/classes. More data on the susceptibility profile of Aspergillus spp. against the new classes of antifungal agents may allow for better treatment options and improved clinical outcomes in the coming years. In the meantime, continuous surveillance studies to monitor the prevalence of environmental and patient prevalence of azole resistance among Aspergillus spp. is absolutely crucial.

Virus-associated fungal infections and lost immune resistance

Invasive fungal infections are an increasing threat to human health. Of recent concern is the emergence of influenza- or SARS-CoV-2-virus-associated invasive fungal infections. Understanding acquired susceptibilities to fungi requires consideration of the collective and newly explored roles of adaptive, innate, and natural immunity. Neutrophils are known to provide host resistance, but new concepts are emerging that implicate innate antibodies, the actions of specialized B1 B cell subsets, and B cell-neutrophil crosstalk in mediating antifungal host resistance. Based on emerging evidence, we propose that virus infections impact on neutrophil and innate B cell resistance against fungi, leading to invasive infections. These concepts provide novel approaches to developing candidate therapeutics with the aim of restoring natural and humoral immunity and boosting neutrophil resistance against fungi.

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.

Immunity to fungi in the lung

The respiratory tree maintains sterilizing immunity against human fungal pathogens. Humans inhale ubiquitous filamentous molds and geographically restricted dimorphic fungal pathogens that form small airborne conidia. In addition, pathogenic yeasts, exemplified by encapsulated Cryptococcus species, and Pneumocystis pose significant fungal threats to the lung. Classically, fungal pneumonia occurs in immune compromised individuals, specifically in patients with HIV/AIDS, in patients with hematologic malignancies, in organ transplant recipients, and in patients treated with corticosteroids and targeted biologics that impair fungal immune surveillance in the lung. The emergence of fungal co-infections during severe influenza and COVID-19 underscores the impairment of fungus-specific host defense pathways in the lung by respiratory viruses and by medical therapies to treat viral infections. Beyond life-threatening invasive syndromes, fungal antigen exposure can exacerbate allergenic disease in the lung. In this review, we discuss emerging principles of lung-specific antifungal immunity, integrate the contributions and cooperation of lung epithelial, innate immune, and adaptive immune cells to mucosal barrier immunity, and highlight the pathogenesis of fungal-associated allergenic disease. Improved understanding of fungus-specific immunity in the respiratory tree has paved the way to develop improved diagnostic, pre-emptive, therapeutic, and vaccine approaches for fungal diseases of the lung.

Analysis of risk factors of fungal superinfections in viral pneumonia patients: A systematic review and meta-analysis

BACKGROUND

Infections with fungi, such as Aspergillus species, have been found as common complications of viral pneumonia. This study aims to determine the risk factors of fungal superinfections in viral pneumonia patients using meta-analysis.

OBJECTIVE

This study aims to determine the risk factors of fungal infection s in viral pneumonia patients using meta-analysis.

METHODS

We reviewed primary literature about fungal infection in viral pneumonia patients published between January 1, 2010 and September 30, 2020, in the Chinese Biomedical Literature, Chinese National Knowledge Infrastructure, Wanfang (China), Cochrane Central Library, Embase, PubMed, and Web of Science databases. These studies were subjected to an array of statistical analyses, including risk of bias and sensitivity analyses.

RESULTS

In this study, we found a statistically significant difference in the incidence of fungal infections in viral pneumonia patients that received corticosteroid treatment as compared to those without corticosteroid treatment (p < .00001). Additionally, regarding the severity of fungal infections, we observed significant higher incidence of invasive pulmonary aspergillosis (IPA) in patients with high Acute Physiology and Chronic Health Evaluation (APACHE) II scores (p < .001), tumors (p = .005), or immunocompromised patients (p < .0001).

CONCLUSIONS

Our research shows that corticosteroid treatment was an important risk factor for the development of fungal infection in patients with viral pneumonia. High APACHE II scores, tumors, and immunocompromised condition are also important risk factors of developing IPA. The diagnosis of fungal infection in viral pneumonia patients can be facilitated by early serum galactomannan (GM) testing, bronchoalveolar lavage fluid Aspergillus antigen testing, culture, and biopsy.

A B1a-natural IgG-neutrophil axis is impaired in viral- and steroid-associated aspergillosis

The lung naturally resists Aspergillus fumigatus (Af) in healthy individuals, but multiple conditions can disrupt this resistance, leading to lethal invasive infections. Core processes of natural resistance and its breakdown are undefined. We investigated three distinct conditions predisposing to lethal aspergillosis-severe SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) infection, influenza A viral pneumonia, and systemic corticosteroid use-in human patients and murine models. We found a conserved and essential coupling of innate B1a lymphocytes, Af-binding natural immunoglobulin G antibodies, and lung neutrophils. Failure of this axis concealed Af from neutrophils, allowing rapid fungal invasion and disease. Reconstituting the axis with immunoglobulin therapy reestablished resistance, thus representing a realistic pathway to repurpose currently available therapies. Together, we report a vital host resistance pathway that is responsible for protecting against life-threatening aspergillosis in the context of distinct susceptibilities.

Therapeutic Approaches for Combating Aspergillus Associated Infection

Now-a-days fungal infection emerges as a significant problem to healthcare management systems due to high frequency of associated morbidity, mortality toxicity, drug-drug interactions, and resistance of the antifungal agents. Aspergillus is the most common mold that cause infection in immunocompromised hosts. It's a hyaline mold that is cosmopolitan and ubiquitous in nature. Aspergillus infects around 10 million population each year with a mortality rate of 30-90%. Clinically available antifungal formulations are restricted to four classes (i.e., polyene, triazole, echinocandin, and allylamine), and each of them have their own limitations associated with the activity spectrum, the emergence of resistance, and toxicity. Consequently, novel antifungal agents with modified and altered chemical structures are required to combat these invasive fungal infections. To overcome these limitations, there is an urgent need for new antifungal agents that can act as potent drugs in near future. Currently, some compounds have shown effective antifungal activity. In this review article, we have discussed all potential antifungal therapies that contain old antifungal drugs, combination therapies, and recent novel antifungal formulations, with a focus on the Aspergillus associated infections.

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.

COVID-19-associated pulmonary aspergillosis is associated with increased in-hospital mortality and prolonged SARS-CoV-2 viral shedding

Background/Purpose

Coronavirus disease 2019 (COVID-19)-associated pulmonary aspergillosis (CAPA) is common in critically ill patients with COVID-19 and is associated with worse outcomes. However, reports on CAPA and its impact on treatment outcomes in Asian populations are limited.

Methods

Patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) reverse transcription polymerase chain reaction-confirmed COVID-19 admitted to intensive care units (ICUs) were retrospectively enrolled in this observational study. The incidence rate of CAPA during ICU admission was investigated. The clinical factors associated with CAPA, including corticosteroid exposure, were analyzed. The impact of CAPA on the treatment outcomes and SARS-CoV-2 viral shedding were explored.

Results

A total of 72 ICU-admitted patients with COVID-19 were included in the analysis. The incidence rate of CAPA was 15.3% (11/72) in all patients and 23% (11/48) in the mechanically ventilated patients. The median time from ICU admission to CAPA diagnosis was 15 days. A lower fibrinogen level (adjusted odds ratio [aOR], 0.983; 95% confidence interval [CI], 0.967–0.999) was independently associated with CAPA. The patients with CAPA had a higher in-hospital mortality rate (55% vs. 13%, p = 0.001) and a longer SARS-CoV-2 viral shedding time (22 days vs. 16 days, p = 0.037) than those without CAPA.

Conclusion

Lower serum fibrinogen levels was independently associated with CAPA among the ICU-admitted patients with COVID-19. The patients with CAPA had a higher in-hospital mortality rate and a longer SARS-CoV-2 viral shedding time than those without CAPA.

Impact of Aspergillus spp. isolation in the first 24 hours of admission in critically ill patients with severe influenza virus pneumonia

OBJECTIVE

To determine the incidence and impact of Aspergillus spp. isolation (AI) on ICU mortality in critically ill patients with severe influenza pneumonia during the first 24h of admission.

DESIGN

Secondary analysis of an observational and prospective cohort study.

SETTING

ICUs voluntary participating in the Spanish severe Influenza pneumonia registry, between June 2009 and June 2019.

PATIENTS

Consecutive patients admitted to the ICU with diagnosis of severe influenza pneumonia, confirmed by real-time polymerase chain reaction.

INTERVENTIONS

None.

MAIN VARIABLES OF INTEREST

Incidence of AI in respiratory samples. Demographic variables, comorbidities, need for mechanical ventilation and the presence of shock according at admission. Acute Physiology and Chronic Health Evaluation II (APACHE II) scale calculated on ICU admission.

RESULTS

3702 patients were analyzed in this study. AI incidence was 1.13% (n=42). Hematological malignancies (OR 4.39, 95% CI 1.92-10.04); HIV (OR 3.83, 95% CI 1.08-13.63), and other immunosuppression situations (OR 4.87, 95% CI 1.99-11.87) were factors independently associated with the presence of Aspergillus spp. The automatic CHAID decision tree showed that hematologic disease with an incidence of 3.3% was the most closely AI related variable. Hematological disease (OR 2.62 95% CI 1.95-3.51), immunosuppression (OR 2.05 95% CI 1.46-2.88) and AI (OR 3.24, 95% CI 1.60-6.53) were variables independently associated with ICU mortality.

CONCLUSIONS

Empirical antifungal treatment in our population may only be justified in immunocompromised patients. In moderate-high risk cases, active search for Aspergillus spp. should be implemented.

Overview of COVID-19-Associated Invasive Fungal Infection

Purpose of Review

Invasive fungal infections are a complication of COVID-19 disease. This article reviews literature characterizing invasive fungal infections associated with COVID-19.

Recent Findings

Multiple invasive fungal infections including aspergillosis, candidiasis, pneumocystosis, other non-Aspergillus molds, and endemic fungi have been reported in patients with COVID-19. Risk factors for COVID-19-associated fungal disease include underlying lung disease, diabetes, steroid or immunomodulator use, leukopenia, and malignancy. COVID-19-associated pulmonary aspergillosis (CAPA) and COVID-19-associated mucormycosis (CAM) are the most common fungal infections described. However, there is variability in the reported incidences related to use of differing diagnostic algorithms.

Summary

Fungal pathogens are important cause of infection in patients with COVID-19, and the diagnostic strategies continue to evolve. Mortality in these patients is increased, and providers should operate with a high index of suspicion. Further studies will be required to elucidate the associations and pathogenesis of these diseases and best management and prevention strategies.

Invasive fungal infections in critically ill COVID-19 patients in a large tertiary university hospital in Israel

An increasing number of studies have tried to determine the incidence of invasive fungal infections (IFIs) in COVID-19 patients. Challenges in the diagnosis of pulmonary aspergillosis in these patients have led to new definitions of COVID-19-associated pulmonary aspergillosis (CAPA). The aim of this study was to determine the incidence and outcomes of and risk factors for IFIs in critically-ill COVID-19 patients, using the new definitions, in a tertiary center in Israel.

Methods

A case-controlled study (from 1 September 2020 to 31 March 2021) in which data from COVID-19 critically-ill patients with a diagnosis of IFI were collected and compared to a control group without IFI.

Results

The incidence of IFI amongst 311 COVID-19 critically-ill patients was 6.1%. 3.5% had CAPA and 3.5% had candidemia. In-hospital mortality was higher amongst patients with IFI compared to those without IFI (89.4% vs 60%, p < 0.03). The most significant predictors of IFI were cardiovascular co-morbidity and carbapenem use.

Conclusions

The low incidence of CAPA in our group of COVID-19 critically-ill patients was consistent with recent reports, underscoring the importance of differentiating between true infection and colonization. Awareness and timely diagnosis of IFIs in COVID-19 critically-ill patients are imperative considering the associated high mortality.

Association between early diagnosis of and inpatient mortality from invasive pulmonary aspergillosis among patients without immunocompromised host factors: a nationwide observational study

OBJECTIVES

The incidence of invasive pulmonary aspergillosis (IPA) among patients without immunocompromised host factors (ICHF) has been described extensively. However, its diagnosis remains challenging. To date, no study has statistically confirmed the efficacy of early IPA diagnosis in patients without ICHF.

METHODS

We conducted a cross-sectional study on mortality from IPA among patients without ICHF, using the Japanese Diagnosis Procedure Combination National Inpatient Database (April 2014-March 2018). The early diagnosis group was defined according to antifungal therapy initiation within 7 days of hospital admission. The delayed diagnosis group was defined according to antifungal therapy initiation between 8 and 28 days of the hospitalization. Associations were estimated using multivariate logistic regression.

RESULTS

A total of 423 patients were registered (early diagnosis group, n = 262, 62%). The early diagnosis group had a lower mortality rate (30%) than the delayed diagnosis group (42%). The early diagnosis group that was treated with voriconazole was associated with lower odds of mortality (odds ratio 0.55, 95% confidence interval 0.31-0.99, P = 0.047). An age of ≥65 years and mechanical ventilation were associated with a higher mortality rate.

CONCLUSION

Early diagnosis along with optimal antifungal treatment are crucial for achieving favorable outcomes among patients with IPA without ICHF.

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.

Cerebral Aspergillosis Complicating COVID Recovery

How to cite this article: Sampley S, Bhasin D, Singh H, Mishra S. Cerebral Aspergillosis Complicating COVID Recovery. Indian J Crit Care Med 2022;26(4):535–536.

Substantive Morphological Descriptions, Phylogenetic Analysis and Single Nucleotide Polymorphisms of Aspergillus Species From Foeniculum vulgare

Ascomycetous fungi are found associated with a wide variety of substrates which range from fresh water to marine ecosystems, tropical to temperate forest soils and deserts, throughout the world over. These demystifying fungi exist as endophytes, pathogens and saprobes. They have been studied due to their ability to contaminate foods and feedstuffs, causing an elaboration of mycotoxins. The objectives of the study included extensive analyses of the morphological features of fungi, especially Aspergilli, which have been presented while studying them on specific mycological media. It is also an elaborate compilation of substantive macro- and micro-morphological characterization of different Aspergilli isolated from the spice Foeniculum vulgare used in India and other countries in the world. Further, a first of its kind attempt has been made to study their relative abundance and frequency of occurrence, molecular phylogeny and genetic relatedness to characterize the Aspergilli into specific sections, groups and clades. Single nucleotide polymorphism (SNP) analysis was carried out to evaluate the functional consequences of nucleotide variations, synonymous and non-synonymous mutations in the protein structure. The study resulted in a total of 3,506 Aspergillus isolates, which were obtained from seventy (70) fennel samples, representing 14 Aspergillus species. The two most frequently found species were A. niger and A. flavus with a relative abundance of 32.24 and 11.63%, respectively. The taxonomy and current placements have been reappraised with suggestions and prospects for future research from six sections namely Terrei, Flavi, Fumigati, Nidulantes, Nigri, and Versicolores. In addition, a total number of 27 isolates were studied and deposited at the National Centre for Biotechnology Information (NCBI) and five Aspergillus species have been identified and are being reported for the first time from the fennel seeds, based on partial sequence analysis of the official fungal barcode namely, Internal Transcribed Spacer (ITS) and a functional gene, beta tubulin gene locus, coupled with phenotypic characterization. SNPs for specific DNA regions have been used to identify variants in Aspergilli obtained from Indian fennel seeds for the first time. The need for a polyphasic approach of morphological identification and genetic characterization of Aspergilli from Foeniculum vulgare is addressed and presented here in adequate detail. Our current work makes extensive use of partial beta-tubulin gene sequences analyses to evaluate the association between SNPs in five Aspergillus species sections.

COVID-19-associated pulmonary aspergillosis in ICU patients in a German reference centre: phenotypic and molecular characterization of Aspergillus fumigatus isolates

Background

COVID‐19‐associated invasive pulmonary aspergillosis (CAPA) is associated with increased mortality. Cases of CAPA caused by azole‐resistant Aspergillus fumigatus strains have been reported.

Objectives

To analyse the twelve‐month CAPA prevalence in a German tertiary care hospital and to characterise clinical A. fumigatus isolates from two German hospitals by antifungal susceptibility testing and microsatellite genotyping.

Patients/Methods.

Retrospective observational study in critically ill adults from intensive care units with COVID‐19 from 17 February 2020 until 16 February 2021 and collection of A. fumigatus isolates from two German centres. EUCAST broth microdilution for four azole compounds and microsatellite PCR with nine markers were performed for each collected isolate (N = 27) and additional for three non‐COVID A. fumigatus isolates.

Results

welve‐month CAPA prevalence was 7.2% (30/414), and the rate of azole‐resistant A. fumigatus isolates from patients with CAPA was 3.7% with detection of one TR34/L98H mutation. The microsatellite analysis revealed no major clustering of the isolates. Sequential isolates mainly showed the same genotype over time.

Conclusions

Our findings demonstrate similar CAPA prevalence to other reports and a low azole‐resistance rate. Genotyping of A. fumigatus showed polyclonal distribution except for sequential isolates.

Resistance profiling of Aspergillus fumigatus to olorofim indicates absence of intrinsic resistance and unveils the molecular mechanisms of acquired olorofim resistance

Olorofim (F901318) is a new antifungal currently under clinical development that shows both in vitro and in vivo activity against a number of filamentous fungi including Aspergillus fumigatus. In this study, we screened A. fumigatus isolates for intrinsic olorofim-resistant A. fumigatus and evaluated the ability of A. fumigatus to acquire an olorofim-resistant phenotype. No intrinsic resistance was found in 975 clinical A. fumigatus isolates. However, we found that isolates with increased olorofim MICs (> 8 mg/L) could be selected using a high number of conidia and olorofim exposure under laboratory conditions. Assessment of the frequency of acquired olorofim resistance development of A. fumigatus was shown to be higher than for voriconazole but lower than for itraconazole. Sequencing the PyrE gene of isogenic isolates with olorofim MICs of >8 mg/L identified various amino acid substitutions with a hotspot at locus G119. Olorofim was shown to have reduced affinity to mutated target protein dihydroorotate dehydrogenase (DHODH) and the effect of these mutations was proven by introducing the mutations directly in A. fumigatus. We then investigated whether G119 mutations were associated with a fitness cost in A. fumigatus. These experiments showed a small but significant reduction in growth rate for strains with a G119V substitution, while strains with a G119C substitution did not exhibit a reduction in growth rate. These in vitro findings were confirmed in an in vivo pathogenicity model.

COVID-19-Associated Pulmonary Aspergillosis in a Tertiary Hospital

Our study aims to assess the prevalence of CAPA (COVID-19-associated pulmonary aspergillosis) and describe the associated risk factors and their impact on mortality. A prospective study was conducted. We included patients with COVID-19 disease who were admitted to the ICU with a diagnosis of respiratory failur. Mycological culture and other biomarkers (calcofluor staining, LFD, LFA, PCR, GM, and B-D-glucan) were performed. A total of 300 patients were included in the study. Thirty-five patients were diagnosed with CAPA (prevalence 11.7%). During admission, 57 patients died (19%), and, in the group of CAPA patients, mortality was 31.4%. In multivariate analysis, independent risk factors associated with CAPA diagnosis were age (OR: 1.05; 95% CI 1.01–1.09; p = 0.037), chronic lung disease (OR: 3.85; 95% CI 1.02–14.9; p = 0.049) and treatment with tocilizumab during admission (OR: 14.5; 95% 6.1–34.9; p = 0.001). Factors independently associated with mortality were age (OR: 1.06; 95% CI 1.01–1.11; p = 0.014) and CAPA diagnosis during admission (OR: 3.34; 95% CI 1.38–8.08; p = 0.007). CAPA is an infection that appears in many patients with COVID-19 disease. CAPA is associated with high mortality rates, which may be reduced by early diagnosis and initiation of appropriate antifungal therapy, so screening of COVID-19 ARDS (acute respiratory distress syndrome) patients for CAPA is essential.

Pathogenesis of Respiratory Viral and Fungal Coinfections

Individuals suffering from severe viral respiratory tract infections have recently emerged as "at risk" groups for developing invasive fungal infections. Influenza virus is one of the most common causes of acute lower respiratory tract infections worldwide. Fungal infections complicating influenza pneumonia are associated with increased disease severity and mortality, with invasive pulmonary aspergillosis being the most common manifestation. Strikingly, similar observations have been made during the current coronavirus disease 2019 (COVID-19) pandemic. The copathogenesis of respiratory viral and fungal coinfections is complex and involves a dynamic interplay between the host immune defenses and the virulence of the microbes involved that often results in failure to return to homeostasis. In this review, we discuss the main mechanisms underlying susceptibility to invasive fungal disease following respiratory viral infections. A comprehensive understanding of these interactions will aid the development of therapeutic modalities against newly identified targets to prevent and treat these emerging coinfections.

Viral infections in lung transplantation

Viral infections account for up to 30% of all infectious complications in lung transplant recipients, remaining a significant cause of morbidity and even mortality. Impact of viral infections is not only due to the direct effects of viral replication, but also to immunologically-mediated lung injury that may lead to acute rejection and chronic lung allograft dysfunction. This has particularly been seen in infections caused by herpesviruses and respiratory viruses. The implementation of universal preventive measures against cytomegalovirus (CMV) and influenza (by means of antiviral prophylaxis and vaccination, respectively) and administration of early antiviral treatment have reduced the burden of these diseases and potentially their role in affecting allograft outcomes. New antivirals against CMV for prophylaxis and for treatment of antiviral-resistant CMV infection are currently being evaluated in transplant recipients, and may continue to improve the management of CMV in lung transplant recipients. However, new therapeutic and preventive strategies are highly needed for other viruses such as respiratory syncytial virus (RSV) or parainfluenza virus (PIV), including new antivirals and vaccines. This is particularly important in the advent of the COVID-19 pandemic, for which several unanswered questions remain, in particular on the best antiviral and immunomodulatory regimen for decreasing mortality specifically in lung transplant recipients. In conclusion, the appropriate management of viral complications after transplantation remain an essential step to continue improving survival and quality of life of lung transplant recipients.

Clinical and Microbiological Characteristics of Culture-Positive, Influenza-Associated Pulmonary Aspergillosis: A Single-Center Study in Southern Taiwan, 2016–2019

This study delineated the characteristics of 24 (11.2%) culture-positive, influenza-associated pulmonary aspergillosis (IAPA) patients out of 215 patients with severe influenza during 2016–2019 in a medical center in southern Taiwan. Twenty (83.3%) patients did not have EORTC/MSG-defined host factors. The mean time from influenza diagnosis to Aspergillus growth was 4.4 days, and 20 (83.3%) developed IAPA within seven days after influenza diagnosis. All patients were treated in intensive care units and all but one (95.8%) received mechanical ventilation. Aspergillus tracheobronchitis was evident in 6 (31.6%) of 19 patients undergoing bronchoscopy. Positive galactomannan testing of either serum or bronchoalveolar lavage was noted in all patients. On computed tomography imaging, IAPA was characterized by peribronchial infiltrates, multiple nodules, and cavities superimposed on ground-glass opacities. Pure Aspergillus growth without bacterial co-isolation in culture was found in 17 (70.8%) patients. A. fumigatus (15, 62.5%), A. flavus (6, 25.0%), and A. terreus (4, 16.7%) were the major causative species. Three patients had mixed Aspergillus infections due to two species, and two had mixed azole-susceptible and azole-resistant A. fumigatus infection. All patients received voriconazole with an all-cause mortality of 41.6%. Of 14 survivors, the mean duration of antifungal use was 40.5 days. In conclusion, IAPA is an early and rapidly deteriorating complication following influenza that necessitates clinical vigilance and prompt diagnostic workup.

Phylogenetic Distribution of csp1 Types in Aspergillus fumigatus and Their Correlates to Azole Antifungal Drug Resistance

In Aspergillus fumigatus, the repetitive region of the csp1 gene is one of the most frequently used loci for intraspecies typing of this human pathogenic mold. Using PCR amplification and Sanger sequencing of only a single marker, csp1 typing is readily available to most laboratories and highly reproducible. Here, I evaluate the usefulness of the csp1 marker for resistance detection and epidemiologic stratification among A. fumigatus isolates. After resolving nomenclature conflicts from published studies and adding novel csp1 types, the number of known types now adds up to 38. Their distribution mostly correlates with A. fumigatus population structure, and they are also meaningful for narrowly defined cases of azole resistance phenotypes. Isolates carrying the pandemic resistance allele TR34/L98H show signs of interclade crossing of strains with t02 or t04A, into the t11 clade. Furthermore, absolute differences in voriconazole MIC values between t02/t04B versus t11 TR34/L98H isolates indicate that the genetic background of resistance mutations may have a pivotal role in cross-resistance phenotypes and, thus, clinical outcome and environmental selection. Despite the general genetic similarity of isolates with identical csp1 types, outcrossing into other clades is also observed. The csp1 type alone, therefore, does not sufficiently discriminate genetic clades to be used as the sole marker in epidemiologic studies. IMPORTANCE Aspergillus fumigatus is a ubiquitously distributed saprophytic mold and a leading cause of invasive aspergillosis in human hosts. Pandemic azole-resistant strains have emerged on a global scale, which are thought to be propagated through use of azole-based fungicides in agriculture. To perform epidemiologic studies, genetic typing of large cohorts is key. Here, I evaluate the usefulness of the frequently used csp1 marker for resistance detection and epidemiologic stratification among A. fumigatus isolates. The phylogenetic distribution of csp1 types mostly correlates with A. fumigatus population structure and is also meaningful for narrowly defined cases of azole resistance phenotypes. Nevertheless, outcrossing of csp1 into other clades is also observed. The csp1 type alone, therefore, does not sufficiently discriminate genetic clades and should not be used as the sole marker in epidemiologic studies.

Overcome Double Trouble: Baloxavir Marboxil Suppresses Influenza Thereby Mitigating Secondary Invasive Pulmonary Aspergillosis

Influenza-associated pulmonary aspergillosis (IAPA) is a global recognized superinfection in critically ill influenza patients. Baloxavir marboxil, a cap-dependent endonuclease inhibitor, is a newly approved anti-influenza therapeutic. Although the benefits as a treatment for influenza are clear, its efficacy against an influenza-A. fumigatus co-infection has yet to be determined. We investigated the therapeutic effect of baloxavir marboxil in a murine model for IAPA. Immunocompetent mice received intranasal instillation of influenza A followed by orotracheal inoculation with Aspergillus fumigatus 4 days later. Administration of baloxavir marboxil or sham was started at day 0, day 2 or day 4. Mice were monitored daily for overall health status, lung pathology with micro-computed tomography (µCT) and fungal burden with bioluminescence imaging (BLI). In vivo imaging was supplemented with virological, mycological and biochemical endpoint investigations. We observed an improved body weight, survival and viral clearance in baloxavir marboxil treated mice. µCT showed less pulmonary lesions and bronchial dilation after influenza and after Aspergillus co-infection in a treatment-dependent pattern. Furthermore, baloxavir marboxil was associated with effective inhibition of fungal invasion. Hence, our results provide evidence that baloxavir marboxil mitigates severe influenza thereby decreasing the susceptibility to a lethal invasive Aspergillus superinfection.