COVID-19 Associated Pulmonary Aspergillosis (CAPA)-From Immunology to Treatment

Navigating the uncertainties of COVID-19 associated aspergillosis (CAPA): A comparison with influenza associated aspergillosis (IAPA)

Invasive pulmonary aspergillosis (IPA) is increasingly recognized as a life-threatening superinfection of severe respiratory viral infections, such as influenza. The pandemic of Coronavirus Disease 2019 (COVID-19) due to emerging SARS-CoV-2 rose concern about the eventuality of IPA complicating COVID-19 in intensive care unit mechanically-ventilated patients. While the association between severe influenza and IPA has been demonstrated, it remains unclear whether SARS-CoV-2 infection represents a specific risk factor for IPA. A variable incidence of such complication has been previously reported, which can be partly attributed to differences in diagnostic strategy and IPA definitions, and possibly local environmental/epidemiological factors. In this article, we discuss the similarities and differences between influenza-associated pulmonary aspergillosis (IAPA) and COVID-19-associated pulmonary aspergillosis (CAPA). Compared to IAPA, the majority of CAPA cases have been classified as putative rather than proven/probable IPA, in the absence of positive serum galactomannan or histopathologic evidence of angio-invasion. Discrimination between Aspergillus airways colonization and CAPA is difficult. Distinct physiopathology and cytokine profiles of influenza and COVID-19 may explain these discrepancies. Whether CAPA represents a distinct entity is still debatable and many questions remain unanswered, such as its actual incidence, the predisposing role of corticosteroids or immunomodulatory drugs, and the indications for antifungal therapy.

Proven Fatal Invasive Aspergillosis in a Patient with COVID-19 and Staphylococcus aureus Pneumonia

There is increasing attention for opportunistic pathogens such as Aspergillus fumigatus complicating SARS-CoV-2 infections in the critically ill. For invasive fungal disease, establishing a clear diagnosis can be challenging due to the invasiveness of diagnostic procedures required for a proven case. Here we present one of the first proven cases of COVID-19-associated pulmonary aspergillosis by positive culture of post-mortem lung biopsy.

State-of-the-art review of secondary pulmonary infections in patients with COVID-19 pneumonia

Background

The incidence of secondary pulmonary infections is not well described in hospitalized COVID-19 patients. Understanding the incidence of secondary pulmonary infections and the associated bacterial and fungal microorganisms identified can improve patient outcomes.

Objective

This narrative review aims to determine the incidence of secondary bacterial and fungal pulmonary infections in hospitalized COVID-19 patients, and describe the bacterial and fungal microorganisms identified.

Method

We perform a literature search and select articles with confirmed diagnoses of secondary bacterial and fungal pulmonary infections that occur 48 h after admission, using respiratory tract cultures in hospitalized adult COVID-19 patients. We exclude articles involving co-infections defined as infections diagnosed at the time of admission by non-SARS-CoV-2 viruses, bacteria, and fungal microorganisms.

Results

The incidence of secondary pulmonary infections is low at 16% (4.8–42.8%) for bacterial infections and lower for fungal infections at 6.3% (0.9–33.3%) in hospitalized COVID-19 patients. Secondary pulmonary infections are predominantly seen in critically ill hospitalized COVID-19 patients. The most common bacterial microorganisms identified in the respiratory tract cultures are Pseudomonas aeruginosa, Klebsiella species, Staphylococcus aureus, Escherichia coli, and Stenotrophomonas maltophilia. Aspergillus fumigatus is the most common microorganism identified to cause secondary fungal pulmonary infections. Other rare opportunistic infection reported such as PJP is mostly confined to small case series and case reports. The overall time to diagnose secondary bacterial and fungal pulmonary infections is 10 days (2–21 days) from initial hospitalization and 9 days (4–18 days) after ICU admission. The use of antibiotics is high at 60–100% involving the studies included in our review.

Conclusion

The widespread use of empirical antibiotics during the current pandemic may contribute to the development of multidrug-resistant microorganisms, and antimicrobial stewardship programs are required for minimizing and de-escalating antibiotics. Due to the variation in definition across most studies, a large, well-designed study is required to determine the incidence, risk factors, and outcomes of secondary pulmonary infections in hospitalized COVID-19 patients.

COVID-19 associated pulmonary aspergillosis in ICU patients: Report of five cases from Argentina

Invasive pulmonary aspergillosis is a complication in critically ill patients with acute respiratory distress syndrome, especially those with severe coronavirus disease-associated pneumonia. In this study, five cases of presumed invasive pulmonary aspergillosis in one immunocompromised and four immunocompetent patients with COVID-19 in Buenos Aires are described. In all cases, the underlying conditions, clinical presentation, fungal diagnostic tests used and their results, features of the chest scan images, antifungals used and clinical outcomes are detailed.

One Health aspects & priority roadmap for fungal diseases : A mini-review

Fungal diseases have not been taken seriously in public health agendas as well as research priorities, despite of globally causing an estimated two million deaths every year, and the emergence of many troublesome fungal pathogens like Candida auris, azole resistant Aspergillus fumigatus, terbinafine and azole resistant dermatophytes, and zoonotic sporotrichosis in humans. Fungi are also responsible for huge losses of agricultural products and stored crops as well as recent massive and unexpected mortality in animals caused by white-nose syndrome in the bats and Chytridiomycosis in amphibians. This review aims to underscore the need for collaborative, multisectoral, and trans-disciplinary approach to include the One Health approach as an essential component of surveillance, prevention, and control of globally emerging fungal diseases. Rigorous evidence based surveillance of the environment as well as strengthening rapid and quality diagnosis of fungal diseases can save millions of lives and reduce significant morbidity.

COVID-19 Impairs Immune Response to Candida albicans

Infection with SARS-CoV-2 can lead to Coronavirus disease-2019 (COVID-19) and result in severe acute respiratory distress syndrome (ARDS). Recent reports indicate an increased rate of fungal coinfections during COVID-19. With incomplete understanding of the pathogenesis and without any causative therapy available, secondary infections may be detrimental to the prognosis. We monitored 11 COVID-19 patients with ARDS for their immune phenotype, plasma cytokines, and clinical parameters on the day of ICU admission and on day 4 and day 7 of their ICU stay. Whole blood stimulation assays with lipopolysaccharide (LPS), heat-killed Listeria monocytogenes (HKLM), Aspergillus fumigatus, and Candida albicans were used to mimic secondary infections, and changes in immune phenotype and cytokine release were assessed. COVID-19 patients displayed an immune phenotype characterized by increased HLA-DR+CD38+ and PD-1+ CD4+ and CD8+ T cells, and elevated CD8+CD244+ lymphocytes, compared to healthy controls. Monocyte activation markers and cytokines IL-6, IL-8, TNF, IL-10, and sIL2Rα were elevated, corresponding to monocyte activation syndrome, while IL-1β levels were low. LPS, HKLM and Aspergillus fumigatus antigen stimulation provoked an immune response that did not differ between COVID-19 patients and healthy controls, while COVID-19 patients showed an attenuated monocyte CD80 upregulation and abrogated release of IL-6, TNF, IL-1α, and IL-1β toward Candida albicans. This study adds further detail to the characterization of the immune response in critically ill COVID-19 patients and hints at an increased susceptibility for Candida albicans infection.

Fatal VAP-related pulmonary aspergillosis by Aspergillus niger in a positive COVID-19 patient

Invasive pulmonary aspergillosis, known as a complication in patients with severe respiratory syndromes, recently showed a correlation with COVID-19 pneumonia, and the clinical characteristics of COVID-19 associated pulmonary aspergillosis (CAPA) have been described. Unfortunately, infections by the Aspergillus genus are often diagnosed in post-mortem time, because of diagnostic delays and a rapid worsening of respiratory conditions. Literature data document, in fact, only few cases of COVID-19 Aspergillus niger coinfection. The aim of this study was to describe a case of a VAP-related probable pulmonary aspergillosis by Aspergillus niger in a COVID-19 patient. Despite the definition of fungal etiology and the rapid administration of antifungal therapy, the patient died while on ventilator support because of severe respiratory impairment.

All You Need to Know and More about the Diagnosis and Management of Rare Mold Infections

Invasive mold infections caused by molds other than Aspergillus spp. or Mucorales are emerging. The reported prevalences of infection due to these rare fungal pathogens vary among geographic regions, driven by differences in climatic conditions, susceptible hosts, and diagnostic capabilities. These rare molds—Fusarium, Lomentospora, and Scedosporium species and others—are difficult to detect and often show intrinsic antifungal resistance. Now, international societies of medical mycology and microbiology have joined forces and created the “Global guideline for the diagnosis and management of rare mould infections: an initiative of the European Confederation of Medical Mycology in cooperation with the International Society for Human and Animal Mycology and the American Society for Microbiology” (published in Lancet Infect Dis, https://doi.org/10.1016/S1473-3099(20)30784-2), with the goal of improving the diagnosis, treatment, prevention, and survival of persons with rare mold infections. The guideline provides cutting-edge guidance for the correct utilization and application of established and new diagnostic and therapeutic options.

COVID-19-associated pulmonary aspergillosis: a prospective single-center dual case series

Background

COVID‐19–associated pulmonary aspergillosis (CAPA) has emerged as an invasive fungal disease, often affecting previously immunocompetent, mechanically ventilated, intensive care unit (ICU) patients. Incidence rates of 3.8%–33.3% have been reported depending on the geographic area, with high (47%) mortality.

Objectives

Here, we describe a single‐centre prospective case series with CAPA cases from both the first (March‐May, n = 5/33) and second (mid‐September through mid‐December, n = 8/33) COVID‐19 wave at a 500‐bed teaching hospital in the Netherlands.

Patients/Methods

In the first COVID‐19 wave, a total of 265 SARS‐CoV‐2 PCR‐positive patients were admitted to our hospital of whom 33 needed intubation and mechanical ventilation. In the second wave, 508 SARS‐CoV‐2 PCR‐positive patients were admitted of whom 33 needed mechanical ventilation. Data were prospectively collected.

Results

We found a significant decrease in COVID‐19 patients needing mechanical ventilation in the ICU in the second wave (p < .01). From these patients, however, a higher percentage were diagnosed with CAPA (24.2% vs 15.2%), although not significant (p = .36). All CAPA patients encountered in the second wave received dexamethasone. Mortality between both groups was similarly high (40%–50%). Moreover, we found environmental TR₃₄/L98H azole‐resistant Aspergillus fumigatus isolates in two separate patients.

Conclusions

In this series, 19.7% (n = 13/66) of mechanically ventilated SARS‐CoV‐2 patients were diagnosed with CAPA. In addition, we found a significant reduction in COVID‐19 patients needing mechanical ventilation on the ICU in the second wave. Numbers are too small to determine whether there is a true difference in CAPA incidence in mechanically ventilated patients between the two waves, and whether it could be attributed to dexamethasone SARS‐CoV‐2 therapy.

Accuracy of galactomannan testing on tracheal aspirates in COVID-19-associated pulmonary aspergillosis

Objective

Our aim was to evaluate the performance of two galactomannan (GM) assays (Platelia Aspergillus EIA, Bio‐Rad^®, and Aspergillus GM LFA, IMMY^®) in tracheal aspirate (TA) samples of consecutive critically ill patients with COVID‐19.

Methods

We included critically ill patients, performed GM‐EIA and GM‐Lateral Flow Assay (GM‐LFA) in TA and followed them until development of COVID‐19‐associated pulmonary aspergillosis (CAPA) or alternate diagnosis. CAPA was defined according to the modified AspICU criteria in patients with SARS‐CoV‐2 infection. We estimated sensitivity, specificity, positive and negative predictive values for GM‐EIA, GM‐LFA, the combination of both or either positive results for GM‐EIA and GM‐LFA. We explored accuracy using different breakpoints, through ROC analysis and Youden index to identify the optimal cut‐offs. We described antifungal treatment and 30‐day mortality.

Results

We identified 14/144 (9.7%) patients with CAPA, mean age was 50.35 (SD 11.9), the median time from admission to CAPA was 8 days; 28.5% received tocilizumab and 30‐day mortality was 57%. ROC analysis and Youden index identified 2.0 OD as the best cut‐off, resulting in sensitivity and specificity of 57.1% and 81.5% for GM‐EIA and 60% and 72.6% for GM‐LFA, respectively.

Conclusions

The diagnostic performance of GM in tracheal aspirates improved after using a cut‐off of 2 OD. Although bronchoalveolar lavage testing is the ideal test, centres with limited access to bronchoscopy may consider this approach to identify or rule out CAPA.

Coronavirus Disease (Covid-19) Associated Mucormycosis (CAM): Case Report and Systematic Review of Literature

Severe coronavirus disease (COVID-19) is currently managed with systemic glucocorticoids. Opportunistic fungal infections are of concern in such patients. While COVID-19 associated pulmonary aspergillosis is increasingly recognized, mucormycosis is rare. We describe a case of probable pulmonary mucormycosis in a 55-year-old man with diabetes, end-stage kidney disease, and COVID-19. The index case was diagnosed with pulmonary mucormycosis 21 days following admission for severe COVID-19. He received 5 g of liposomal amphotericin B and was discharged after 54 days from the hospital. We also performed a systematic review of the literature and identified seven additional cases of COVID-19 associated mucormycosis (CAM). Of the eight cases included in our review, diabetes mellitus was the most common risk factor. Three subjects had no risk factor other than glucocorticoids for COVID-19. Mucormycosis usually developed 10–14 days after hospitalization. All except the index case died. In two subjects, CAM was diagnosed postmortem. Mucormycosis is an uncommon but serious infection that complicates the course of severe COVID-19. Subjects with diabetes mellitus and multiple risk factors may be at a higher risk for developing mucormycosis. Concurrent glucocorticoid therapy probably heightens the risk of mucormycosis. A high index of suspicion and aggressive management is required to improve outcomes.

COVID-19-Associated Pulmonary Aspergillosis, March-August 2020

Pneumonia caused by severe acute respiratory syndrome coronavirus 2 emerged in China at the end of 2019. Because of the severe immunomodulation and lymphocyte depletion caused by this virus and the subsequent administration of drugs directed at the immune system, we anticipated that patients might experience fungal superinfection. We collected data from 186 patients who had coronavirus disease-associated pulmonary aspergillosis (CAPA) worldwide during March-August 2020. Overall, 182 patients were admitted to the intensive care unit (ICU), including 180 with acute respiratory distress syndrome and 175 who received mechanical ventilation. CAPA was diagnosed a median of 10 days after coronavirus disease diagnosis. Aspergillus fumigatus was identified in 80.3% of patient cultures, 4 of which were azole-resistant. Most (52.7%) patients received voriconazole. In total, 52.2% of patients died; of the deaths, 33.0% were attributed to CAPA. We found that the cumulative incidence of CAPA in the ICU ranged from 1.0% to 39.1%.

The impact of COVID-19 pandemic on AIDS-related mycoses and fungal neglected tropical diseases: Why should we worry?

The World Health Organization (WHO) considers mycetoma, chromoblastomycosis, and paracoccidioidomycosis to be fungal neglected tropical diseases (FNTDs). Depending on climatic, cultural, and economic contexts, these diseases have a similar geographical distribution as many other diseases, particularly tuberculosis (TB) and malaria, but are often less targeted by the national and many international healthcare systems. Another subgroup of fungal infections, such as candidiasis, cryptococcosis, pneumocystosis, histoplasmosis, and to a lesser extent, aspergillosis, are known as AIDS-related mycoses. Although antiretroviral therapy (ART) has been able to decrease the mortality rate of these diseases, particularly cryptococcosis, the disproportionately low distribution of funds to their diagnosis and treatment remains an obstacle in saving and improving the lives of patients affected. A new wave of viral diseases dubbed the Coronavirus Disease 2019 (COVID-19) hit the world at the end of 2019. Due to progressive symptoms and high mortality rates of COVID-19 compared to fungal infections, particularly the FNTDs, funding is currently allocated predominantly for diagnostic and therapeutic research on COVID-19. As a result, advances in FNTDs and AIDS-related mycosis care are considerably reduced. This paper explores the association between COVID-19, FNTDs, and AIDS-related mycoses with a predictive perspective.

Invasive pulmonary aspergillosis in the COVID-19 era: An expected new entity

OBJECTIVES

Information on the recently COVID-19-associated pulmonary aspergillosis (CAPA) entity is scarce. We describe eight CAPA patients, compare them to colonised ICU patients with coronavirus disease 2019 (COVID-19), and review the published literature from Western countries.

METHODS

Prospective study (March to May, 2020) that included all COVID-19 patients admitted to a tertiary hospital. Modified AspICU and European Organization for Research and Treatment of Cancer/Mycoses Study Group (EORTC/MSG) criteria were used.

RESULTS

COVID-19-associated pulmonary aspergillosis was diagnosed in eight patients (3.3% of 239 ICU patients), mostly affected non-immunocompromised patients (75%) with severe acute respiratory distress syndrome (ARDS) receiving corticosteroids. Diagnosis was established after a median of 15 days under mechanical ventilation. Bronchoalveolar lavage was performed in two patients with positive Aspergillus fumigatus cultures and galactomannan (GM) index. Serum GM was positive in 4/8 (50%). Thoracic CT scan findings fulfilled EORTC/MSG criteria in one case. Isavuconazole was used in 4/8 cases. CAPA-related mortality was 100% (8/8). Compared with colonised patients, CAPA subjects were administered tocilizumab more often (100% vs. 40%, p = .04), underwent longer courses of antibacterial therapy (13 vs. 5 days, p = .008), and had a higher all-cause mortality (100% vs. 40%, p = .04). We reviewed 96 similar cases from recent publications: 59 probable CAPA (also putative according modified AspICU), 56 putative cases and 13 colonisations according AspICU algorithm; according EORTC/MSG six proven and two probable. Overall, mortality in the reviewed series was 56.3%.

CONCLUSIONS

COVID-19-associated pulmonary aspergillosis must be considered a serious and potentially life-threatening complication in patients with severe COVID-19 receiving immunosuppressive treatment.

Autopsy Proven Pulmonary Mucormycosis Due to Rhizopus microsporus in a Critically Ill COVID-19 Patient with Underlying Hematological Malignancy

Viral infections can cause acute respiratory distress syndrome (ARDS), consequently leading to susceptibility for secondary pulmonary infections. Over the past few weeks, a number of studies have reported on secondary pulmonary aspergillosis complicating severe COVID-19. We report the case of a 53-year old male patient with secondary acute myeloid leukemia (AML) who suffered from COVID-19 ARDS and was diagnosed postmortem with mucormycosis.

Are All Patients with Cancer at Heightened Risk for Severe Coronavirus Disease 2019 (COVID-19)?

Cancer patients are traditionally considered at high risk for complicated respiratory viral infections, due to their underlying immunosuppression. In line with this notion, early case series reported high mortality rates of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in patients with malignancy. However, subsequent large, prospective, epidemiological surveys indicate that the risk for severe coronavirus disease 2019 (COVID-19) may be largely attributed to the multiple confounders operating in this highly heterogeneous population of patients, rather than the cancer or its treatment per se. We critically discuss the conundrums of SARS-CoV-2 infection in cancer patients and underscore mechanistic insights on the outcome of COVID-19 as it relates to cancer therapy and the type and status of the underlying malignancy. Not all cancer patients are similarly at risk for a complicated COVID-19 course. A roadmap is needed for translational and clinical research on COVID-19 in this challenging group of patients.

Autopsy findings after long-term treatment of COVID-19 patients with microbiological correlation

Between April and June 2020, i.e., during the first wave of pandemic coronavirus disease 2019 (COVID-19), 55 patients underwent long-term treatment in the intensive care unit at the University Hospital of Regensburg. Most of them were transferred from smaller hospitals, often due to the need for an extracorporeal membrane oxygenation system. Autopsy was performed in 8/17 COVID-19-proven patients after long-term treatment (mean: 33.6 days). Autopsy revealed that the typical pathological changes occurring during the early stages of the disease (e.g., thrombosis, endothelitis, capillaritis) are less prevalent at this stage, while severe diffuse alveolar damage and especially coinfection with different fungal species were the most conspicuous finding. In addition, signs of macrophage activation syndrome was detected in 7 of 8 patients. Thus, fungal infections were a leading cause of death in our cohort of severely ill patients and may alter clinical management of patients, particularly in long-term periods of treatment.

Aspergillus fumigatus and Its Allergenic Ribotoxin Asp f I: Old Enemies but New Opportunities for Urine-Based Detection of Invasive Pulmonary Aspergillosis Using Lateral-Flow Technology

Invasive pulmonary aspergillosis (IPA) caused by Aspergillus fumigatus is a life-threatening lung disease of immunocompromised patients. Diagnosis currently relies on non-specific chest CT, culture of the fungus from invasive lung biopsy, and detection of the cell wall carbohydrate galactomannan (GM) in serum or in BAL fluids recovered during invasive bronchoscopy. Urine provides an ideal bodily fluid for the non-invasive detection of pathogen biomarkers, with current urine-based immunodiagnostics for IPA focused on GM. Surrogate protein biomarkers might serve to improve disease detection. Here, we report the development of a monoclonal antibody (mAb), PD7, which is specific to A. fumigatus and related species in the section Fumigati, and which binds to its 18 kDa ribotoxin Asp f I. Using PD7, we show that the protein is secreted during hyphal development, and so represents an ideal candidate for detecting invasive growth. We have developed a lateral-flow device (Afu-LFD®) incorporating the mAb which has a limit of detection of ~15 ng Asp f I/mL urine. Preliminary evidence of the test's diagnostic potential is demonstrated with urine from a patient with acute lymphoid leukaemia with probable IPA. The Afu-LFD® therefore provides a potential novel opportunity for non-invasive urine-based detection of IPA caused by A. fumigatus.

COVID-19-Associated Invasive Aspergillosis: Data from the UK National Mycology Reference Laboratory

COVID-19-associated pulmonary aspergillosis (CAPA) was recently reported as a potential infective complication affecting critically ill patients with acute respiratory distress syndrome following severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, with incidence rates varying from 8 to 33% depending on the study. However, definitive diagnosis of CAPA is challenging. Standardized diagnostic algorithms and definitions are lacking, clinicians are reticent to perform aerosol-generating bronchoalveolar lavages for galactomannan testing and microscopic and cultural examination, and questions surround the diagnostic sensitivity of different serum biomarkers.

COVID-19-associated pulmonary aspergillosis (CAPA) was recently reported as a potential infective complication affecting critically ill patients with acute respiratory distress syndrome following severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, with incidence rates varying from 8 to 33% depending on the study. However, definitive diagnosis of CAPA is challenging. Standardized diagnostic algorithms and definitions are lacking, clinicians are reticent to perform aerosol-generating bronchoalveolar lavages for galactomannan testing and microscopic and cultural examination, and questions surround the diagnostic sensitivity of different serum biomarkers. Between 11 March and 14 July 2020, the UK National Mycology Reference Laboratory received 1,267 serum and respiratory samples from 719 critically ill UK patients with COVID-19 and suspected pulmonary aspergillosis. The laboratory also received 46 isolates of Aspergillus fumigatus from COVID-19 patients (including three that exhibited environmental triazole resistance). Diagnostic tests performed included 1,000 (1-3)-β-d-glucan and 516 galactomannan tests on serum samples. The results of this extensive testing are presented here. For a subset of 61 patients, respiratory specimens (bronchoalveolar lavage specimens, tracheal aspirates, and sputum samples) in addition to serum samples were submitted and subjected to galactomannan testing, Aspergillus-specific PCR, and microscopy and culture. The incidence of probable/proven and possible CAPA in this subset of patients was approximately 5% and 15%, respectively. Overall, our results highlight the challenges in biomarker-driven diagnosis of CAPA, especially when only limited clinical samples are available for testing, and the importance of a multimodal diagnostic approach involving regular and repeat testing of both serum and respiratory samples.

Defining and managing COVID-19-associated pulmonary aspergillosis: the 2020 ECMM/ISHAM consensus criteria for research and clinical guidance

Severe acute respiratory syndrome coronavirus 2 causes direct damage to the airway epithelium, enabling aspergillus invasion. Reports of COVID-19-associated pulmonary aspergillosis have raised concerns about it worsening the disease course of COVID-19 and increasing mortality. Additionally, the first cases of COVID-19-associated pulmonary aspergillosis caused by azole-resistant aspergillus have been reported. This article constitutes a consensus statement on defining and managing COVID-19-associated pulmonary aspergillosis, prepared by experts and endorsed by medical mycology societies. COVID-19-associated pulmonary aspergillosis is proposed to be defined as possible, probable, or proven on the basis of sample validity and thus diagnostic certainty. Recommended first-line therapy is either voriconazole or isavuconazole. If azole resistance is a concern, then liposomal amphotericin B is the drug of choice. Our aim is to provide definitions for clinical research and up-to-date recommendations for clinical management of the diagnosis and treatment of COVID-19-associated pulmonary aspergillosis.

Risk factors associated with COVID-19-associated pulmonary aspergillosis in ICU patients: a French multicentric retrospective cohort

OBJECTIVES

The main objective of this study was to determine the incidence of invasive pulmonary aspergillosis (IPA) in patients with coronavirus disease 2019 (COVID-19) admitted to the intensive care unit (ICU), and to describe the patient characteristics associated with IPA occurrence and to evaluate its impact on prognosis.

METHODS

We conducted a retrospective cohort study including all successive COVID-19 patients, hospitalized in four ICUs, with secondary deterioration and one or more respiratory samples sent to the mycology department. We used a strengthened IPA testing strategy including seven mycological criteria. Patients were classified as probable IPA according to the European Organization for Research and Treatment of Cancer (EORTC)/Mycoses Study Group Education and Research Consortium (MSGERC) classification if immunocompromised, and according to the recent COVID-19-associated IPA classification otherwise.

RESULTS

Probable IPA was diagnosed in 21 out of the 366 COVID-19 patients (5.7%) admitted to the ICU and in the 108 patients (19.4%) who underwent respiratory sampling for deterioration. No significant differences were observed between patients with and without IPA regarding age, gender, medical history and severity on admission and during hospitalization. Treatment with azithromycin for ≥3 days was associated with the diagnosis of probable IPA (odds ratio 3.1, 95% confidence interval 1.1-8.5, p = 0.02). A trend was observed with high-dose dexamethasone and the occurrence of IPA. Overall mortality was higher in the IPA patients (15/21, 71.4% versus 32/87, 36.8%, p < 0.01).

CONCLUSION

IPA is a relatively frequent complication in severe COVID-19 patients and is responsible for increased mortality. Azithromycin, known to have immunomodulatory properties, may contribute to increase COVID-19 patient's susceptibility to IPA.

Advances against Aspergillosis and Mucormycosis

The 9th meeting of Advances Against Aspergillosis in beautiful Lugano, Switzerland clearly had the most drama of any of the previous meetings, exceeding even the 1st one, in San Francisco, when we, the Co-Organizers, weren't sure that although we had a great educational idea, and had put together a great list of speakers and topics, we might have few attendees, and go bankrupt! (The story of the birth efforts in initiating these meetings is described, for the historical record [...].

Drug-Resistant Fungi: An Emerging Challenge Threatening Our Limited Antifungal Armamentarium

The high clinical mortality and economic burden posed by invasive fungal infections (IFIs), along with significant agricultural crop loss caused by various fungal species, has resulted in the widespread use of antifungal agents. Selective drug pressure, fungal attributes, and host- and drug-related factors have counteracted the efficacy of the limited systemic antifungal drugs and changed the epidemiological landscape of IFIs. Species belonging to Candida, Aspergillus, Cryptococcus, and Pneumocystis are among the fungal pathogens showing notable rates of antifungal resistance. Drug-resistant fungi from the environment are increasingly identified in clinical settings. Furthermore, we have a limited understanding of drug class-specific resistance mechanisms in emerging Candida species. The establishment of antifungal stewardship programs in both clinical and agricultural fields and the inclusion of species identification, antifungal susceptibility testing, and therapeutic drug monitoring practices in the clinic can minimize the emergence of drug-resistant fungi. New antifungal drugs featuring promising therapeutic profiles have great promise to treat drug-resistant fungi in the clinical setting. Mitigating antifungal tolerance, a prelude to the emergence of resistance, also requires the development of effective and fungal-specific adjuvants to be used in combination with systemic antifungals.

The Aspergillus Lateral Flow Assay for the Diagnosis of Invasive Aspergillosis: an Update

Purpose of Review

To review the data on the Aspergillus lateral flow assay for the diagnosis of invasive Aspergillosis.

Recent Findings

Aspergillus spp. cause a wide spectrum of disease with invasive aspergillosis (IA) as its most severe manifestation. Early and reliable diagnosis of disease is crucial to decrease associated morbidity and mortality, and enable prompt initiation of treatment for IA. Most recently, non-culture-based tests, such as Aspergillus galactomannan (GM), have been useful in early identification and treatment of patients with IA. However, cost, turnaround time, and variable performance indifferent populations at risk for IA remain significant drawbacks to the use of this test. Several diagnostic tests for IA have been developed, including the sōna Aspergillus GM Lateral flow assay (GM-LFA) rapid test.

Summary

The GM-LFA has shown excellent performance for the diagnosis of IA in patients with hematologic malignancy and may be a viable option for settings where ELISA GM testing is not feasible. Further evaluation of the GM-LFA in the non-hematology setting is ongoing, including in solid organ transplant recipients and patients in the intensive care unit.

Immunological response to COVID-19 and its role as a predisposing factor in invasive aspergillosis

The world is involved with a pandemic coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2. The clinical manifestations of reported COVID-19-associated pulmonary impairments range from asymptomatic infections to a pneumonia-induced acute respiratory distress syndrome that requires mechanical ventilation. Fungal superinfections complicating the clinical course remain underexplored. Angiotensin-converting enzyme 2, the receptor for COVID-19 that is mainly expressed in airway epithelia and lung parenchyma, is considered an important regulator of innate immunity. With regard to the viral-cell interaction, imbalanced immune regulation between protective and altered responses caused by the exacerbation of inflammatory responses should be considered a major contributor to secondary pulmonary aspergillosis. In addition, the complex inherited factors, age-related changes, and lifestyle may also affect immune responses. The complication and persistence of invasive aspergillosis have been well described in patients with severe influenza or COVID-19. However, there is a scarcity of information about the immunological mechanisms predisposing patients with COVID-19 to fungal co-infections. Therefore, this study was conducted to investigate the aforementioned domain.

Covid-19-Associated Pulmonary Aspergillosis: The Other Side of the Coin

The immune response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a critical factor in the clinical presentation of COVID-19, which may range from asymptomatic to a fatal, multi-organ disease. A dysregulated immune response not only compromises the ability of the host to resolve the viral infection, but may also predispose the individual to secondary bacterial and fungal infections, a risk to which the current therapeutic immunomodulatory approaches significantly contribute. Among the secondary infections that may occur in COVID-19 patients, coronavirus-associated pulmonary aspergillosis (CAPA) is emerging as a potential cause of morbidity and mortality, although many aspects of the disease still remain unresolved. With this opinion, we present the current view of CAPA and discuss how the same mechanisms that underlie the dysregulated immune response in COVID-19 increase susceptibility to Aspergillus infection. Likewise, resorting to endogenous pathways of immunomodulation may not only restore immune homeostasis in COVID-19 patients, but also reduce the risk for aspergillosis. Therefore, CAPA represents the other side of the coin in COVID-19 and our advances in the understanding and treatment of the immune response in COVID-19 should represent the framework for the study of CAPA.

It's all in your head: antifungal immunity in the brain

As the incidence rate of invasive fungal infections has increased with the use of modern medical interventions, so too has the occurrence of fungi invading the brain. Fungi such as Candida albicans, Cryptococcus neoformans, and Aspergillus fumigatus often infect immunocompromised individuals, and can use several strategies to invade the central nervous system (CNS) by penetrating the blood-brain barrier. Once in the brain parenchyma the specialized resident immune cells need to effectively recognize the fungus and mount an appropriate immune response to clear the infection, without causing debilitating immune-mediated toxicity and neuronal damage. Here we review the current knowledge pertaining to the antifungal response of the CNS and highlight areas where future research is required.

Invasive pulmonary aspergillosis associated with COVID-19 in a kidney transplant recipient

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) might increase the risk of invasive pulmonary aspergillosis (IPA). Although several case reports and small series have been reported in the general population, scarce information is available regarding coronavirus disease 2019 (COVID-19)-associated IPA in the setting of solid organ transplantation. We describe a case of a kidney transplant recipient with severe COVID-19 that was subsequently diagnosed with probable IPA on the basis of the repeated isolation of Aspergillus fumigatus in sputum cultures, repeatedly increased serum (1 → 3)-β-d-glucan levels, and enlarging cavitary nodules in the CT scan. The evolution was favorable after initiation of isavuconazole and nebulized liposomal amphotericin B combination therapy and the withdrawal of immunosuppression.

Lipopolysaccharide Binding Protein and Bactericidal/Permeability-Increasing Protein as Biomarkers for Invasive Pulmonary Aspergillosis

Early diagnosis of invasive pulmonary aspergillosis (IPA) is crucial to prevent lethal disease in immunocompromized hosts. So far, lipopolysaccharide binding protein (LBP) and bactericidal/permeability-increasing protein (BPI) levels have not been evaluated as biomarkers for IPA. IL-8, previously introduced as a biomarker for IPA, was also included in this study. Bronchoalveolar lavage fluid (BALF) of IPA patients and control patients with non-infectious lung disease was collected according to clinical indications. Measurements in BALF displayed significantly higher levels of LBP (p < 0.0001), BPI (p = 0.0002) and IL-8 (p < 0.0001) in IPA compared to control patients. Receiver operating characteristic curve analysis revealed higher AUC for LBP (0.98, 95% CI 0.95–1.00) than BPI (0.84, 95% CI 0.70–0.97; p = 0.0301). Although not significantly different, AUC of IL-8 (0.93, 95% CI 0.85–1.00) also tended to be higher than AUC for BPI (p = 0.0624). When the subgroup of non-hematological patients was analyzed, test performance of LBP (AUC 0.99, 95% CI 0.97–1.00), BPI (AUC 0.97, 95% CI 0.91–1.00) and IL-8 (AUC 0.96, 95% CI: 0.90–1.00) converged. In conclusion, LBP and—to a lesser extend—BPI displayed high AUCs that were comparable to those of IL-8 for diagnosis of IPA in BALF. Further investigations are worthwhile, especially in non-hematological patients in whom sensitive biomarkers for IPA are lacking.

Global Sexual Fertility in the Opportunistic Pathogen Aspergillus fumigatus and Identification of New Supermater Strains

A sexual cycle in Aspergillus fumigatus was first described in 2009 with isolates from Dublin, Ireland. However, the extent to which worldwide isolates can undergo sexual reproduction has remained unclear. In this study a global collection of 131 isolates was established with a near 1:1 ratio of mating types. All isolates were crossed to MAT1-1 or MAT1-2 Irish strains, and a subset of isolates from different continents were crossed together. Ninety seven percent of isolates were found to produce cleistothecia with at least one mating partner, showing that sexual fertility is not limited to the Irish population but is a characteristic of global A. fumigatus. However, large variation was seen in numbers of cleistothecia produced per cross, suggesting differences in the possibility for genetic exchange between strains in nature. The majority of crosses produced ascospores with >50% germination rates, but with wide variation evident. A high temperature heat shock was required to induce ascospore germination. Finally, a new set of highly fertile MAT1-1 and MAT1-2 supermater strains were identified and pyrimidine auxotrophs generated for community use. Results provide insights into the potential for the A. fumigatus sexual cycle to generate genetic variation and allow gene flow of medically important traits.

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

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

COVID-19-Associated Candidiasis (CAC): An Underestimated Complication in the Absence of Immunological Predispositions?

The recent global pandemic of COVID-19 has predisposed a relatively high number of patients to acute respiratory distress syndrome (ARDS), which carries a risk of developing super-infections. Candida species are major constituents of the human mycobiome and the main cause of invasive fungal infections, with a high mortality rate. Invasive yeast infections (IYIs) are increasingly recognized as s complication of severe COVID-19. Despite the marked immune dysregulation in COVID-19, no prominent defects have been reported in immune cells that are critically required for immunity to Candida. This suggests that relevant clinical factors, including prolonged ICU stays, central venous catheters, and broad-spectrum antibiotic use, may be key factors causing COVID-19 patients to develop IYIs. Although data on the comparative performance of diagnostic tools are often lacking in COVID-19 patients, a combination of serological and molecular techniques may present a promising option for the identification of IYIs. Clinical awareness and screening are needed, as IYIs are difficult to diagnose, particularly in the setting of severe COVID-19. Echinocandins and azoles are the primary antifungal used to treat IYIs, yet the therapeutic failures exerted by multidrug-resistant Candida spp. such as C. auris and C. glabrata call for the development of new antifungal drugs with novel mechanisms of action.

Pan-Echinocandin-Resistant Candida glabrata Bloodstream Infection Complicating COVID-19: A Fatal Case Report

Coinfections with bacteria or fungi may be a frequent complication of COVID-19, but coinfections with Candida species in COVID-19 patients remain rare. We report the 53-day clinical course of a complicated type-2 diabetes patient diagnosed with COVID-19, who developed bloodstream infections initially due to methicillin-resistant Staphylococcus aureus, secondly due to multidrug-resistant Gram-negative bacteria, and lastly due to a possibly fatal Candida glabrata. The development of FKS-associated pan-echinocandin resistance in the C. glabrata isolated from the patient after 13 days of caspofungin treatment aggravated the situation. The patient died of septic shock shortly before the prospect of receiving potentially effective antifungal therapy. This case emphasizes the importance of early diagnosis and monitoring for antimicrobial drug-resistant coinfections to reduce their unfavorable outcomes in COVID-19 patients.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

A national strategy to diagnose COVID-19 associated invasive fungal disease in the ICU

Background

Fungal co-infection is a recognised complication of respiratory virus infections, increasing morbidity and mortality, but can be readily treated if diagnosed early. An increasing number of small studies describing aspergillosis in COVID-19 patients with severe respiratory distress are being reported, but comprehensive data is lacking. The aim of this study was to determine the incidence, risk factors and impact of invasive fungal disease in adult COVID-19 patients with severe respiratory distress.

Methods

An evaluation of a national, multi-centre, prospective cohort evaluation of an enhanced testing strategy to diagnose invasive fungal disease in COVID-19 intensive care patients. Results were used to generate a mechanism to define aspergillosis in future COVID-19 patients.

Results

One-hundred and thirty-five adults (median age: 57, M/F: 2·2/1) were screened. The incidence was 26.7% (14.1% aspergillosis, 12·6% yeast infections). The overall mortality rate was 38%; 53% and 31% in patients with and without fungal disease, respectively (P: 0.0387). The mortality rate was reduced by the use of antifungal therapy (Mortality: 38·5% in patients receiving therapy versus 90% in patients not receiving therapy (P: 0.008). The use of corticosteroids (P: 0.007) and history of chronic respiratory disease (P: 0.05) increased the likelihood of aspergillosis.

Conclusions

Fungal disease occurs frequently in critically ill, mechanically ventilated COVID-19 patients. The survival benefit observed in patients receiving antifungal therapy implies that the proposed diagnostic and defining criteria are appropriate. Screening using a strategic diagnostic approach and antifungal prophylaxis of patients with risk factors will likely enhance the management of COVID-19 patients.

Is the COVID-19 Pandemic a Good Time to Include Aspergillus Molecular Detection to Categorize Aspergillosis in ICU Patients? A Monocentric Experience

(1) Background: The diagnosis of invasive aspergillosis (IA) in an intensive care unit (ICU) remains a challenge and the COVID-19 epidemic makes it even harder. Here, we evaluated Aspergillus PCR input to help classifying IA in SARS-CoV-2-infected patients. (2) Methods: 45 COVID-19 patients were prospectively monitored twice weekly for Aspergillus markers and anti-Aspergillus serology. We evaluated the concordance between (I) Aspergillus PCR and culture in respiratory samples, and (II) blood PCR and serum galactomannan. Patients were classified as putative/proven/colonized using AspICU algorithm and two other methods. (3) Results: The concordance of techniques applied on respiratory and blood samples was moderate (kappa = 0.58 and kappa = 0.63, respectively), with a higher sensitivity of PCR. According to AspICU, 9/45 patients were classified as putative IA. When incorporating PCR results, 15 were putative IA because they met all criteria, probably with a lack of specificity in the context of COVID-19. Using a modified AspICU algorithm, eight patients were classified as colonized and seven as putative IA. (4) Conclusion: An appreciation of the fungal burden using PCR and Aspergillus serology was added to propose a modified AspICU algorithm. This proof of concept seemed relevant, as it was in agreement with the outcome of patients, but will need validation in larger cohorts.