COVID-19-associated pulmonary aspergillosis in mechanically ventilated patients: a prospective, multicentre UK study.

BACKGROUND: Invasive pulmonary aspergillosis is a complication of severe COVID-19, with regional variation in reported incidence and mortality. We describe the incidence, risk factors and mortality associated with COVID-19-associated pulmonary aspergillosis (CAPA) in a prospective, multicentre UK cohort. METHODS: From March 2020 to March 2021, 266 mechanically ventilated adults with COVID-19 were enrolled across 5 UK hospital intensive care units (ICUs). CAPA was defined using European Confederation for Medical Mycology and the International Society for Human and Animal Mycology criteria and fungal diagnostics performed on respiratory and serum samples. RESULTS: Twenty-nine of 266 patients (10.9%) had probable CAPA, 14 (5.2%) possible CAPA and none proven CAPA. Probable CAPA was diagnosed a median of 9 (IQR 7-16) days after ICU admission. Factors associated with probable CAPA after multivariable logistic regression were cumulative steroid dose given within 28 days prior to ICU admission (adjusted OR (aOR) 1.16; 95% CI 1.01 to 1.43 per 100 mg prednisolone-equivalent), receipt of an interleukin (IL)-6 inhibitor (aOR 2.79; 95% CI 1.22 to 6.48) and chronic obstructive pulmonary disease (COPD) (aOR 4.78; 95% CI 1.13 to 18.13). Mortality in patients with probable CAPA was 55%, vs 46% in those without. After adjustment for immortal time bias, CAPA was associated with an increased risk of 90-day mortality (HR 1.85; 95% CI 1.07 to 3.19); however, this association did not remain statistically significant after further adjustment for confounders (adjusted HR 1.57; 95% CI 0.88 to 2.80). There was no difference in mortality between patients with CAPA prescribed antifungals (9 of 17; 53%) and those who were not (7 of 12; 58%) (p=0.77). INTERPRETATION: In this first prospective UK study, probable CAPA was associated with corticosteroid use, receipt of IL-6 inhibitors and pre-existing COPD. CAPA did not impact mortality following adjustment for prognostic variables.

Clinical characteristics, diagnosis, outcomes and lung microbiome analysis of invasive pulmonary aspergillosis in the community-acquired pneumonia patients.

BACKGROUND: Invasive pulmonary aspergillosis (IPA) remains underestimated in patients with community-acquired pneumonia (CAP). This study aims to describe clinical features and outcomes of IPA in CAP patients, assess diagnostic performance of metagenomic next-generation sequencing (mNGS) for IPA and analyse lung microbiome via mNGS data. METHODS: This retrospective cohort study included CAP patients from 22 April 2019 to 30 September 2021. Clinical and microbiological data were analysed. Diagnostic performance of mNGS was compared with traditional detection methods. The lung microbiome detected by mNGS was characterised and its association with clinical features was evaluated. MAIN RESULTS: IPA was diagnosed in 26 (23.4%) of 111 CAP patients. Patients with IPA displayed depressed immunity, higher hospital mortality (30.8% vs 11.8%) and intensive care unit mortality (42.1% vs 17.5%) compared with patients without IPA. The galactomannan (GM) antigen test had the highest sensitivity (57.7%) in detecting the Aspergillus spp, followed by mNGS (42.3%), culture (30.8%) and smear (7.7%). The mNGS, culture and smear had 100% specificity, while GM test had 92.9% specificity. The microbial structure of IPA significantly differed from non-IPA patients (p<0.001; Wilcoxon test). Nineteen different species were significantly correlated with clinical outcomes and laboratory biomarkers, particularly for Streptococcus salivarius, Prevotella timonensis and Human betaherpesvirus 5. CONCLUSIONS: Our results reveal that patients with Aspergillus infection tend to have a higher early mortality rate. The mNGS may be suggested as a complement to routine microbiological test in diagnosis of patients at risk of Aspergillus infection. The lung microbiota is associated with inflammatory, immune and metabolic conditions of IPA, and thus influences clinical outcomes.

Nodules, nodes and non-functioning macrophages: A risk with ibrutinib therapy.

We describe the case of a 70-year-old never smoker with chronic lymphocytic leukaemia, treated with single agent ibrutinib therapy. Chest imaging noted nodular change and mediastinal lymphadenopathy, which showed avid uptake on positron emission tomography and guided subsequent biopsies (bronchoscopy using endobronchial ultrasound, mediastinoscopy). Despite negative aspergillus blood immunology tests, he was found to have invasive aspergillosis, which is a known risk with ibrutinib therapy. He has since been successfully treated with antifungal therapy.

A prospective longitudinal study of chronic pulmonary aspergillosis in pulmonary tuberculosis in Indonesia (APICAL).

OBJECTIVES: Chronic pulmonary aspergillosis (CPA) can complicate recovery from pulmonary TB. CPA may also be misdiagnosed as bacteriologically negative TB. This study aimed to determine the incidence of CPA in patients treated for TB in Indonesia, a country with a high incidence of TB. METHODS: In this prospective, longitudinal cohort study in patients treated for pulmonary TB, clinical, radiological and laboratory findings were analysed. Sputum was collected for fungal culture and TB PCR. Patients were assessed at baseline (0-8 weeks) and at the end (5-6 months) of TB therapy. CPA diagnosis was based on symptoms (≥3 months), characteristic radiological features and positive Aspergillus serology, and categorised as proven, probable and possible. RESULTS: Of the 216 patients recruited, 128 (59%) were followed up until end of TB therapy. At baseline, 91 (42%) had microbiological evidence for TB. Aspergillus-specific IgG was positive in 64 (30%) patients and went from negative to positive in 16 (13%) patients during TB therapy. The incidence rates of proven and probable CPA at baseline were 6% (n=12) and 2% (n=5) and end of TB therapy 8% (n=10) and 5% (n=7), respectively. Six patients (two with confirmed TB) developed an aspergilloma. Diabetes mellitus was a significant risk factor for CPA (p=0.040). Persistent cough (n=5, 50%; p=0.005) and fatigue (n=6, 60%; p=0.001) were the most common symptoms in CPA. CONCLUSION: CPA should be considered a relatively frequent differential diagnosis in patients with possible or proven TB in Indonesia. Lack of awareness and limited access to Aspergillus-specific IgG tests and CT imaging are obstacles in establishing a CPA diagnosis.

Lung microbiota predict invasive pulmonary aspergillosis and its outcome in immunocompromised patients.

RATIONALE: Recent studies have revealed that the lung microbiota of critically ill patients is altered and predicts clinical outcomes. The incidence of invasive fungal infections, namely, invasive pulmonary aspergillosis (IPA), in immunocompromised patients is increasing, but the clinical significance of variations in lung bacterial communities is unknown. OBJECTIVES: To define the contribution of the lung microbiota to the development and course of IPA. METHODS AND MEASUREMENTS: We performed an observational cohort study to characterise the lung microbiota in 104 immunocompromised patients using bacterial 16S ribosomal RNA gene sequencing on bronchoalveolar lavage samples sampled on clinical suspicion of infection. Associations between lung dysbiosis in IPA and pulmonary immunity were evaluated by quantifying alveolar cytokines and chemokines and immune cells. The contribution of microbial signatures to patient outcome was assessed by estimating overall survival. MAIN RESULTS: Patients diagnosed with IPA displayed a decreased alpha diversity, driven by a markedly increased abundance of the Staphylococcus, Escherichia, Paraclostridium and Finegoldia genera and a decreased proportion of the Prevotella and Veillonella genera. The overall composition of the lung microbiome was influenced by the neutrophil counts and associated with differential levels of alveolar cytokines. Importantly, the degree of bacterial diversity at the onset of IPA predicted the survival of infected patients. CONCLUSIONS: Our results reveal the lung microbiota as an understudied source of clinical variation in patients at risk of IPA and highlight its potential as a diagnostic and therapeutic target in the context of respiratory fungal diseases.

Infections due to dysregulated immunity: an emerging complication of cancer immunotherapy.

Immune checkpoint inhibitors (ICIs) have revolutionised cancer treatment. However, immune-related adverse events (irAEs) are a common side effect which can mimic infection. Additionally, treatment of irAEs with corticosteroids and other immunosuppressant agents can lead to opportunistic infection, which we have classed as immunotherapy infections due to immunosuppression. However, emerging reports demonstrate that some infections can be precipitated by ICIs in the absence of immunosuppressive treatment, in contrast to the majority of reported cases. These infections are characterised by a dysregulated inflammatory immune response, and so we propose they are described as immunotherapy infections due to dysregulated immunity. This review summarises the rapidly emerging evidence of these phenomena and proposes a new framework for considering infection in the context of cancer immunotherapy.

Interferon gamma replacement as salvage therapy in chronic pulmonary aspergillosis: effects on frequency of acute exacerbation and all-cause hospital admission.

Chronic pulmonary aspergillosis (CPA) is often poorly responsive to antifungal treatment; secondary infections increase morbidity/mortality, particularly in progressive cases. Interferon gamma (IFNγ) has been implicated in not only Aspergillus control but also bacterial clearance. Clinical notes of patients with CPA treated with IFNγ (2011-2018) were retrospectively hand-searched. In patients treated for >12 months (n=20), the frequency of acute exacerbation reduced from 3.1 to 1.4 episodes/year (p=0.006) in the 12 months after treatment initiation compared with the 12 months before. A significant reduction in the frequency of hospital admissions/year was also observed (0.8 to 0.3, p=0.04). These findings support further prospective studies.

Airway epithelial phosphoinositide 3-kinase-δ contributes to the modulation of fungi-induced innate immune response.

BACKGROUND: Respiratory fungal exposure is known to be associated with severe allergic lung inflammation. Airway epithelium is an essential controller of allergic inflammation. An innate immune recognition receptor, nucleotide-binding domain, leucine-rich-containing family, pyrin-domain-containing-3 (NLRP3) inflammasome, and phosphoinositide 3 kinase (PI3K)-δ in airway epithelium are involved in various inflammatory processes. OBJECTIVES: We investigated the role of NLRP3 inflammasome in fungi-induced allergic lung inflammation and examined the regulatory mechanism of NLRP3 inflammasome, focusing on PI3K-δ in airway epithelium. METHODS: We used two in vivo models induced by exposure to Aspergillus fumigatus (Af) and Alternaria alternata (Aa), as well as an Af-exposed in vitro system. We also checked NLRP3 expression in lung tissues from patients with allergic bronchopulmonary aspergillosis (ABPA). RESULTS: Assembly/activation of NLRP3 inflammasome was increased in the lung of Af-exposed mice. Elevation of NLRP3 inflammasome assembly/activation was observed in Af-stimulated murine and human epithelial cells. Similarly, pulmonary expression of NLRP3 in patients with ABPA was increased. Importantly, neutralisation of NLRP3 inflammasome derived IL-1ß alleviated pathophysiological features of Af-induced allergic inflammation. Furthermore, PI3K-δ blockade improved Af-induced allergic inflammation through modulation of NLRP3 inflammasome, especially in epithelial cells. This modulatory role of PI3K-δ was mediated through the regulation of mitochondrial reactive oxygen species (mtROS) generation. NLRP3 inflammasome was also implicated in Aa-induced eosinophilic allergic inflammation, which was improved by PI3K-δ blockade. CONCLUSION: These findings demonstrate that fungi-induced assembly/activation of NLRP3 inflammasome in airway epithelium may be modulated by PI3K-δ, which is mediated partly through the regulation of mtROS generation. Inhibition of PI3K-δ may have potential for treating fungi-induced severe allergic lung inflammation.

Gastroesophageal Reflux Disease and Pulmonary Diseases Associated with Aspergillosis: Is There a Connection?

INTRODUCTION: We studied the relationship between GORD and allergic bronchopulmonary aspergillosis (ABPA), chronic pulmonary aspergillosis (CPA), or Aspergillus bronchitis. BACKGROUND: Gastroesophageal reflux disease (GORD) is well known to initiate or exacerbate pulmonary inflammatory conditions, inducing bronchial asthma and chronic obstructive lung disease. METHODS: We reviewed four patients referred with elevated Aspergillus serology markers and marked pulmonary symptoms for ABPA, CPA, and Aspergillus bronchitis, and discussed the underlying pathophysiological relationship with GORD. Data were collected retrospectively from medical records included age, gender, predisposing factors for ABPA, chronic pulmonary aspergillosis, or Aspergillus bronchitis; presence of nocturnal reflux, nausea, epigastric pain, Medical Research Council dyspnea scale score, pH manometry data, endoscopic results (ulcers, Barrett's esophagus), treatment of GORD [proton-pump inhibitors (PPIs), surgical operation]; history of smoking, alcohol consumption; concomitant COPD; serological markers (anti-Aspergillus IgG, anti-Aspergillus IgE), and antifungal treatment. RESULTS: Four patients with GORD were studied; following PPIs administration two achieved clinical improvement. One had ABPA, one CPA, and two had Aspergillus bronchitis; median age was 57 years [range 39-71]; males-to-females ratio was 1:3. Serological markers for aspergillosis were: median total IgE antibodies 573 KIU/L [range 13.1-850], median Aspergillus IgE-specific antibodies 1.2 kAU/L [range <0.4-24.7], and median Aspergillus IgG titers 71 mg/L [range 20-119]. Aspergillus fumigatus grew in one sputum sample. CONCLUSION: Clinicians caring for patients with gastroesophageal reflux disease presenting with elevated Aspergillus IgG or IgE antibodies should maintain a high index of suspicion for this association and proceed to appropriate evaluations, including laryngoscopy and endoscopy, initiating specific PPI-directed therapy when indicated.

Clinical manifestations and outcomes of pulmonary aspergillosis: experience from Pakistan.

INTRODUCTION: Pulmonary aspergillosis has variable course of illness, severity and outcomes depending on underlying conditions. There is limited data available on the clinical manifestations and outcome of pulmonary aspergillosis from Pakistan. METHODS: To determine the clinical manifestations and outcome of pulmonary aspergillosis in a tertiary care hospital a retrospective study was conducted from 2004 to 2014 in patients admitted with pulmonary aspergillosis at the Aga Khan University Hospital Karachi, Pakistan. RESULTS: Of the 280 cases with provisional diagnosis of aspergillosis 69 met the inclusion criteria. The mean age was 45±15.7 years, 48 (69.6%) were men and 21 (30.4%) had diabetes mellitus (DM). The average length of hospital stay (LOS) was 10.61±9.08 days. Aspergillus fumigatus was the most common (42.0%), followed by Aspergillus flavus (28.9%). More than one-third of patients previously had tuberculosis (TB) (39.13%). The commonest pulmonary manifestation was chronic pulmonary aspergillosis (CPA) 47 (68.1%) followed by invasive pulmonary aspergillosis (IPA) 12 (17.4%) and subacute invasive aspergillosis (SAIA) 8 (11.6%). Surgical excision was performed in 28 patients (40.57%). Intensive care unit admission was required for 18 patients (26.08%). Case fatality rate was 14/69 (20.3%). DM, mean LOS and hypoxic respiratory failure were identified as independent risk factors of mortality on multivariate analysis. CONCLUSION: A. fumigatus was the most frequent species found especially in patients with prior TB. CPA was the commonest pulmonary manifestation seen as post TB sequel. Diabetes, hypoxic respiratory failure and increased LOS were independent predictors of poor outcomes. Overall patients had good outcome with CPA compared with SAIA and IPA.

Phosphoinositide 3-kinase-δ regulates fungus-induced allergic lung inflammation through endoplasmic reticulum stress.

BACKGROUND: Sensitisation with Aspergillus fumigatus (Af) is known to be associated with severe allergic lung inflammation, but the mechanism remains to be clarified. Phosphoinositide 3-kinase (PI3K)-δ and endoplasmic reticulum (ER) stress are suggested to be involved in steroid-resistant lung inflammation. We aimed to elucidate the role of PI3K-δ and its relationship with ER stress in fungus-induced allergic lung inflammation. METHODS: Using Af-exposed in vivo and in vitro experimental systems, we examined whether PI3K-δ regulates ER stress, thereby contributing to steroid resistance in fungus-induced allergic lung inflammation. Moreover, we checked expression of an ER stress marker in lung tissues isolated from patients with allergic bronchopulmonary aspergillosis. RESULTS: Af-exposed mice showed that ER stress markers, unfolded protein response (UPR)-related proteins, phosphorylated Akt, generation of mitochondrial reactive oxygen species (mtROS), eosinophilic allergic inflammation, and airway hyperresponsiveness (AHR) were increased in the lung. Similarly, glucose-regulated protein 78 was increased in lung tissues of patients with ABPA. A PI3K-δ inhibitor reduced Af-induced increases in ER stress markers, UPR-related proteins, allergic inflammation and AHR in mice. However, dexamethasone failed to reduce Af-induced allergic inflammation, AHR and elevation of ER stress. Administration of an ER stress inhibitor or a mtROS scavenger improved Af-induced allergic inflammation. The PI3K-δ inhibitor reduced Af-induced mtROS generation and the mtROS scavenger ameliorated ER stress. In primary cultured tracheal epithelial cells, Af-induced ER stress was inhibited by blockade of PI3K-δ. CONCLUSIONS: These findings suggest that PI3K-δ regulates Af-induced steroid-resistant eosinophilic allergic lung inflammation through ER stress.

Republished: The clinical spectrum of pulmonary aspergillosis.

The clinical presentation of Aspergillus lung disease is determined by the interaction between fungus and host. Invasive aspergillosis develops in severely immunocompromised patients, including those with neutropenia, and increasingly in the non-neutropenic host, including lung transplant recipients, the critically ill patients and patients on steroids. A high index of suspicion is required in patients without the classical risk factors as early presentation is usually silent and non-specific, pyrexia uncommon and timely treatment is crucial for survival. Invasive aspergillosis has also been diagnosed in normal hosts after massive exposure to fungal spores. Chronic pulmonary aspergillosis affects patients without obvious immune compromise, but with an underlying lung condition such as COPD or sarcoidosis, prior or concurrent TB or non-tuberculous mycobacterial disease. Aspergillus bronchitis may be responsible for persistent respiratory symptoms in patients with Aspergillus detected repeatedly in sputum without evidence of parenchymal Aspergillus disease, especially in patients with bronchiectasis and cystic fibrosis. Allergic bronchopulmonary aspergillosis affects patients with asthma and cystic fibrosis, and is important to recognise as permanent lung or airways damage may accrue if untreated. Changes in the classification of Aspergillus allergic lung disease have been proposed recently. Cases of extrinsic allergic alveolitis and chronic pulmonary aspergillosis have been observed after Aspergillus exposure. Asymptomatic colonisation of the respiratory tract needs close monitoring as it can lead to clinical disease especially with ongoing immunosuppression. The various syndromes should be viewed as a semicontinuous spectrum of disease and one form may evolve into another depending on the degree of ongoing immunosuppression.

Nebulised liposomal amphotericin B for Aspergillus lung diseases: case series and literature review.

Over the past 10 years the incidence of Aspergillus spp. has significantly increased, and it is now the most widespread air transmission fungal pathogen in developed countries. Whatever the clinical expression of the pulmonary disease and despite recent progress in antifungal drug therapy, morbidity and mortality related to aspergillosis lung disease still constitute a serious threat for immunosuppressed or mildly immunocompromised patients. Moreover, the treatments currently used have many limitations due to adverse effects and drug interactions. Finally, subjects exposed to azoles present an increased risk of Aspergillus-resistant strain emergence. We have reported five cases with aspergillosis lung diseases that were either difficult to control or in which patients had a contra-indication to triazole therapy, but which showed durable improvement following the administration of nebulised liposomal amphotericin B. Our alternative strategy could be of interest for patients with aspergillosis lung disease who otherwise cannot be conventionally treated by triazoles.

The clinical spectrum of pulmonary aspergillosis.

The clinical presentation of Aspergillus lung disease is determined by the interaction between fungus and host. Invasive aspergillosis develops in severely immunocompromised patients, including those with neutropenia, and increasingly in the non-neutropenic host, including lung transplant recipients, the critically ill patients and patients on steroids. A high index of suspicion is required in patients without the classical risk factors as early presentation is usually silent and non-specific, pyrexia uncommon and timely treatment is crucial for survival. Invasive aspergillosis has also been diagnosed in normal hosts after massive exposure to fungal spores. Chronic pulmonary aspergillosis affects patients without obvious immune compromise, but with an underlying lung condition such as COPD or sarcoidosis, prior or concurrent TB or non-tuberculous mycobacterial disease. Aspergillus bronchitis may be responsible for persistent respiratory symptoms in patients with Aspergillus detected repeatedly in sputum without evidence of parenchymal Aspergillus disease, especially in patients with bronchiectasis and cystic fibrosis. Allergic bronchopulmonary aspergillosis affects patients with asthma and cystic fibrosis, and is important to recognise as permanent lung or airways damage may accrue if untreated. Changes in the classification of Aspergillus allergic lung disease have been proposed recently. Cases of extrinsic allergic alveolitis and chronic pulmonary aspergillosis have been observed after Aspergillus exposure. Asymptomatic colonisation of the respiratory tract needs close monitoring as it can lead to clinical disease especially with ongoing immunosuppression. The various syndromes should be viewed as a semicontinuous spectrum of disease and one form may evolve into another depending on the degree of ongoing immunosuppression.