The role of surgical debridement in different clinical manifestations of invasive aspergillosis

Aspergillus fumigatus-a systematic review to inform the World Health Organization priority list of fungal pathogens

Recognizing the growing global burden of fungal infections, the World Health Organization established a process to develop a priority list of fungal pathogens (FPPL). In this systematic review, we aimed to evaluate the epidemiology and impact of invasive infections caused by Aspergillus fumigatus to inform the first FPPL. The pre-specified criteria of mortality, inpatient care, complications and sequelae, antifungal susceptibility, risk factors, preventability, annual incidence, global distribution, and emergence were used to search for relevant articles between 1 January 2016 and 10 June 2021. Overall, 49 studies were eligible for inclusion. Azole antifungal susceptibility varied according to geographical regions. Voriconazole susceptibility rates of 22.2% were reported from the Netherlands, whereas in Brazil, Korea, India, China, and the UK, voriconazole susceptibility rates were 76%, 94.7%, 96.9%, 98.6%, and 99.7%, respectively. Cross-resistance was common with 85%, 92.8%, and 100% of voriconazole-resistant A. fumigatus isolates also resistant to itraconazole, posaconazole, and isavuconazole, respectively. The incidence of invasive aspergillosis (IA) in patients with acute leukemia was estimated at 5.84/100 patients. Six-week mortality rates in IA cases ranged from 31% to 36%. Azole resistance and hematological malignancy were poor prognostic factors. Twelve-week mortality rates were significantly higher in voriconazole-resistant than in voriconazole-susceptible IA cases (12/22 [54.5%] vs. 27/88 [30.7%]; P = .035), and hematology patients with IA had significantly higher mortality rates compared with solid-malignancy cases who had IA (65/217 [30%] vs. 14/78 [18%]; P = .04). Carefully designed surveillance studies linking laboratory and clinical data are required to better inform future FPPL.

Synergistic and potential antifungal properties of tailored, one pot multicomponent monoterpenes co-delivered with fluconazole encapsulated nanostructure lipid carrier

Frequent and variant infections are caused by the virtue of opportunistic fungi pathogens. Candidiasis, aspergillosis, and mucormycosis are pathogenic microorganisms that give rise to vast fungal diseases that alternate between moderate to fatal in severity. The use of fluconazole as an antifungal drug was limited due to the acquired resistance in some types of Candida and other fungal species. This study aims to consolidate fluconazole's biological effectiveness against several pathogenic fungi. Six active monoterpenes (MTs) of carvacrol, linalool, geraniol, α-terpinene, citronellal, and nerolidol were selected and encapsulated in nanostructure lipid carrier (NLC) with (NLC-Flu-MTs) and/without (NLC-MTs) fluconazole in one nanoformulation to determine if they will act synergistically or not? The synthesized nanoformulation NLC-Flu-MTs and NLC-MTs exhibited very good particle size of 144.5 nm and 138.6 nm for size and zeta potential values of (- 23.5 mV) and (- 20.3 mV), respectively. Transmission electron microscope investigation confirmed that the synthesized NLCs have regular and spherical shape. The abundance and concentration of the six released monoterpenes were determined, as a novel approach, using GC-MS with very good results and validity. In-vitro antifungal screening was done before and after nano co-delivery against seven pathogenic, and aggressive fungi of Candida tropicalis, Candida krusei, Candida glabrata, Geotrichum Candidum, Candidaalbicans, Aspergillus Niger, and mucor circinelloides. Inhibition Zone diameter (IZD) and the minimum inhibitory concentration (MIC) were measured. Nanoformulations NLC-Flu-MTs and NLC-MTs manifested potential and unique biological susceptibility against all the tested microorganisms with reduced (MIC) values, especially against Candida Tropicalis (MIC = 0.97 µg/ml) which represents 16-fold of the value shown by NLC-MTs (MIC = 15.6 µg/ml) and 64-fold of fluconazole free before nanoformulation (MIC = 62.5 µg/ml). The efficiency of nanomaterials, particularly NLC-Flu-MTs, has become evident in the diminishing value of MIC which affirmed the synergism between fluconazole and the other six monoterpenes.

Social determinants of health as drivers of fungal disease

Disparities in social determinants of health (SDOH) play a significant role in causing health inequities globally. The physical environment, including housing and workplace environment, can increase the prevalence and spread of fungal infections. A number of professions are associated with increased fungal infection risk and are associated with low pay, which may be linked to crowded and sub-optimal living conditions, exposure to fungal organisms, lack of access to quality health care, and risk for fungal infection. Those involved and displaced from areas of armed conflict have an increased risk of invasive fungal infections. Lastly, a number of fungal plant pathogens already threaten food security, which will become more problematic with global climate change. Taken together, disparities in SDOH are associated with increased risk for contracting fungal infections. More emphasis needs to be placed on systematic approaches to better understand the impact and reducing the health inequities associated with these disparities.

Fungal Endocarditis: Pathophysiology, Epidemiology, Clinical Presentation, Diagnosis, and Management

Fungal endocarditis accounts for 1% to 3% of all infective endocarditis cases, is associated with high morbidity and mortality (>70%), and presents numerous challenges during clinical care. Candida spp. are the most common causes of fungal endocarditis, implicated in over 50% of cases, followed by Aspergillus and Histoplasma spp. Important risk factors for fungal endocarditis include prosthetic valves, prior heart surgery, and injection drug use. The signs and symptoms of fungal endocarditis are nonspecific, and a high degree of clinical suspicion coupled with the judicious use of diagnostic tests is required for diagnosis. In addition to microbiological diagnostics (e.g., blood culture for Candida spp. or galactomannan testing and PCR for Aspergillus spp.), echocardiography remains critical for evaluation of potential infective endocarditis, although radionuclide imaging modalities such as 18F-fluorodeoxyglucose positron emission tomography/computed tomography are increasingly being used. A multimodal treatment approach is necessary: surgery is usually required and should be accompanied by long-term systemic antifungal therapy, such as echinocandin therapy for Candida endocarditis or voriconazole therapy for Aspergillus endocarditis.

Salvage Treatment for Invasive Aspergillosis and Mucormycosis: Challenges, Recommendations and Future Considerations

Invasive mold diseases are devastating systemic infections which demand meticulous care in selection, dosing, and therapy monitoring of antifungal drugs. Various circumstances regarding PK/PD properties of the applied drug, resistance/tolerance of the causative pathogen or host intolerability can lead to failure of the initial antifungal therapy. This necessitates treatment adaption in the sense of switching antifungal drug class or potentially adding another drug for a combination therapy approach. In the current state of drastically limited options of antifungal drug classes adaption of therapy remains challenging. Current guidelines provide restricted recommendations only and emphasize individual approaches. However, novel antifungals, incorporating innovative mechanisms of action, show promising results in late stage clinical development. These will expand options for salvage therapy in the future potentially as monotherapy or in combination with conventional or other novel antifungals. We outline current recommendations for salvage therapy including PK/PD considerations as well as elucidate possible future treatment options for invasive aspergillosis and mucormycosis.

Aspergillus fumigatus and aspergillosis: From basics to clinics

The airborne fungus Aspergillus fumigatus poses a serious health threat to humans by causing numerous invasive infections and a notable mortality in humans, especially in immunocompromised patients. Mould-active azoles are the frontline therapeutics employed to treat aspergillosis. The global emergence of azole-resistant A. fumigatus isolates in clinic and environment, however, notoriously limits the therapeutic options of mould-active antifungals and potentially can be attributed to a mortality rate reaching up to 100 %. Although specific mutations in CYP 51A are the main cause of azole resistance, there is a new wave of azole-resistant isolates with wild-type CYP 51A genotype challenging the efficacy of the current diagnostic tools. Therefore, applications of whole-genome sequencing are increasingly gaining popularity to overcome such challenges. Prominent echinocandin tolerance, as well as liver and kidney toxicity posed by amphotericin B, necessitate a continuous quest for novel antifungal drugs to combat emerging azole-resistant A. fumigatus isolates. Animal models and the tools used for genetic engineering require further refinement to facilitate a better understanding about the resistance mechanisms, virulence, and immune reactions orchestrated against A. fumigatus. This review paper comprehensively discusses the current clinical challenges caused by A. fumigatus and provides insights on how to address them.

Physiological Responses of Aspergillus niger Challenged with Itraconazole

Aspergillus niger is an opportunistic pathogen commonly found in a variety of indoor and outdoor environments. An environmental isolate of A. niger from a pig farm was resistant to itraconazole, and in-depth investigations were conducted to better understand cellular responses that occur during growth when this pathogen is exposed to an antifungal. Using a combination of cultivation techniques, antibiotic stress testing, and label-free proteomics, this study investigated the physiological and metabolic responses of A. niger to sublethal levels of antifungal stress. Challenging A. niger with itraconazole inhibited growth, and the MIC was estimated to be > 16 mg · liter^-1 Through the proteome analysis, 1,305 unique proteins were identified. During growth with 2 and 8 mg · liter^-1 itraconazole, a total of 91 and 50 proteins, respectively, were significantly differentially expressed. When challenged with itraconazole, A. niger exhibited decreased expression of peroxidative enzymes, increased expression of an ATP-binding cassette (ABC) transporter most likely involved as an azole efflux pump, and inhibited ergosterol synthesis; however, several ergosterol biosynthesis proteins increased in abundance. Furthermore, reduced expression of proteins involved in the production of ATP and reducing power from both the tricarboxylic acid (TCA) and glyoxylate cycles was observed. The mode of action of triazoles in A. niger therefore appears more complex than previously anticipated, and these observations may help highlight future targets for antifungal treatment.

How Long Do We Need to Treat an Invasive Mold Disease in Hematology Patients? Factors Influencing Duration of Therapy and Future Questions

Treatment duration for invasive mold disease (IMD) in patients with hematological malignancy is not standardized and is a challenging subject in antifungal stewardship. Concerns for IMD relapse during subsequent reinduction or consolidation chemotherapy or graft versus host disease treatment in hematopoietic stem cell transplant recipients often results in prolonged or indefinite antifungal treatment. There are no validated criteria that predict when it is safe to stop antifungals. Decisions are individualized and depend on the offending fungus, site and extent of IMD, comorbidities, hematologic disease prognosis, and future plans for chemotherapy or transplantation. Recent studies suggest that FDG-PET/CT could help discriminate between active and residual fungal lesions to support decisions for safely stopping antifungals. Validation of noninvasive biomarkers for monitoring treatment response, tests for quantifying the "net state of immunosuppression," and genetic polymorphisms associated with poor fungal immunity could lead to a personalized assessment for the continued need for antifungal therapy.

Delayed Diagnosis of a Diffuse Invasive Gastrointestinal Aspergillosis in an Immunocompetent Patient

Invasive aspergillosis represents a clinical picture frequently associated with host's immunosuppression which usually involves a high morbidity and mortality. In general, the most frequent fungal entry is the lungs with secondary hematogenous dissemination, but there are other hypotheses like a gastrointestinal portal of entry. There are some rare publications of cases with invasive aspergillosis in immunocompetent patients. We present the case of an immunocompetent patient without any risk factors except for age, ICU stay, and surgical intervention, who developed a septic shock by invasive gastrointestinal aspergillosis as primary infection. Due to the unusualness of the case, despite all the measures taken, the results were obtained postmortem. We want to emphasize the need not to underestimate the possibility for an invasive aspergillosis in an immunocompetent patient. Not only pulmonary but also gastrointestinal aspergillosis should be taken into account in the differential diagnosis to avoid a delay of treatment.

Aspergillus fumigatus and Aspergillosis in 2019

Aspergillus fumigatus is a saprotrophic fungus; its primary habitat is the soil. In its ecological niche, the fungus has learned how to adapt and proliferate in hostile environments. This capacity has helped the fungus to resist and survive against human host defenses and, further, to be responsible for one of the most devastating lung infections in terms of morbidity and mortality. In this review, we will provide (i) a description of the biological cycle of A. fumigatus; (ii) a historical perspective of the spectrum of aspergillus disease and the current epidemiological status of these infections; (iii) an analysis of the modes of immune response against Aspergillus in immunocompetent and immunocompromised patients; (iv) an understanding of the pathways responsible for fungal virulence and their host molecular targets, with a specific focus on the cell wall; (v) the current status of the diagnosis of different clinical syndromes; and (vi) an overview of the available antifungal armamentarium and the therapeutic strategies in the clinical context. In addition, the emergence of new concepts, such as nutritional immunity and the integration and rewiring of multiple fungal metabolic activities occurring during lung invasion, has helped us to redefine the opportunistic pathogenesis of A. fumigatus.

Surgical resection for persistent localized pulmonary fungal infection prior to allogeneic hematopoietic stem cell transplantation: Analysis of six cases

OBJECTIVE

Although invasive fungal disease (IFD) is an important complication in allogeneic hematopoietic stem cell transplantation (HSCT), the clinical significance of surgery, including the role of surgical resection for persistent pulmonary fungal disease prior to allogeneic HSCT in the current era with a variety of available antifungal agents, is controversial. We investigated the role of surgical resection.

METHODS

We retrospectively investigated six patients who underwent surgical resection of suspected pulmonary fungal disease prior to allogeneic HSCT between April 2007 and June 2016 at our medical center.

RESULTS

We present six patients who underwent surgical resection of suspected pulmonary fungal disease prior to allogeneic HSCT. In our case series, three of four patients who were given a presurgical diagnosis of possible IFD were given a proven diagnosis after surgery, including two cases of invasive aspergillosis (IA) and one case of mucormycosis. All surgeries were performed by video-assisted thoracic surgery (VATS) for lobectomy without major complications. Recurrence of IFD was not observed after allogeneic HSCT in any of the six patients.

CONCLUSION

Our experience indicated that surgical resection of persistent localized pulmonary lesions of IFD before allogeneic HSCT was helpful for obtaining a definitive diagnosis and might be useful for reducing recurrence after HSCT.

Invasive Fungal Carotiditis: A Rare Manifestation of Cranial Invasive Fungal Disease: Case Series and Systematic Review of the Literature

Background

Rhinosinusitis, malignant otitis externa, and skull base osteomyelitis represent a spectrum of cranial invasive fungal disease (IFD). These syndromes have distinct characteristics, yet they may progress to involve similar structures, resulting in inflammation and invasion of the adjacent internal carotid artery (ICA). Invasive fungal carotiditis can have devastating consequences, including cerebral infarction, subarachnoid hemorrhage, and death.

Methods

We retrospectively studied all patients diagnosed with cranial IFD and carotid involvement at our institution from 2003 to 2018. We also searched Medline/PubMed for reports of Aspergillus or Mucorales cranial infections with ICA involvement. All cases with mycologic evidence of cranial IFD and radiographic or pathologic evidence of ICA involvement were included.

Results

We identified 78 cases of invasive fungal carotiditis between 1958 and 2018, including 4 cases at our own institution. Forty-one were caused by Aspergillus and 37 by Mucorales species. Presenting symptoms included vision changes (73%), cranial nerve palsy (69%), and headache (42%). Carotid events included occlusion, aneurysm formation, and vessel rupture. Cerebral infarcts occurred in 50% of cases. Mortality at 6 weeks, 12 weeks, and 2 years was 27%, 41%, and 71% respectively. The median time from symptom onset to death was 150 days for cases due to Aspergillus and 51 days for cases due to Mucorales species.

Conclusions

Invasive fungal carotiditis is a rare but morbid manifestation of cranial IFD. Early suspicion of IFD and administration of antifungal treatment, vascular imaging, and endovascular interventions should be considered to reduce the high mortality of this disease.

Dermatologic Conditions of the Early Post-Transplant Period in Hematopoietic Stem Cell Transplant Recipients

Hematopoietic stem cell transplants (HSCTs) are used to treat a variety of conditions, including hematologic malignancies, bone marrow failure syndromes, and immunodeficiencies. Over 60,000 HSCTs are performed annually worldwide, and the numbers continue to increase. Indeed, as new conditioning regimens develop, more and more individuals, including those of older age, will be eligible for transplants. Nevertheless, although HSCTs are clearly a life-saving and necessary treatment for thousands of patients per year, there is still substantial morbidity and mortality associated with the procedure. Of note, skin eruptions in the post-HSCT period are frequent and often significantly reduce quality of life in recipients. Moreover, these cutaneous findings sometimes herald an underlying systemic condition, presenting possible opportunities for timelier intervention. Dermatologists therefore play a vital role in distinguishing life-threatening conditions from benign issues and prompting recognition of critical complications earlier in their course. This article aims to review the major dermatologic conditions occurring in the early post-HSCT period.

[Aspergillus in airway material : Ignore or treat?]

Fungi of the genus Aspergillus are ubiquitously present. Even though humans inhale Aspergillus spores daily under natural conditions, Aspergillus-associated pulmonary diseases only occur under special circumstances. Whether an Aspergillus-associated disease develops and which type of Aspergillus-associated disease develops depends on the constitution of the host. The spectrum of Aspergillus-associated pulmonary diseases ranges from allergic diseases, such as hypersensitivity pneumonitis to allergic infectious diseases, such as allergic bronchopulmonary aspergillosis (ABPA) and bronchocentric granulomatosis (BG) to infectious diseases, such as invasive (IA) or semi-invasive aspergillosis (SIA) and chronic pulmonary aspergillosis (CPA). Identification of Aspergillus spp. from sputum or bronchopulmonary secretions is not sufficient for a definitive diagnosis of Aspergillus-associated infections. The gold standard is the identification of Aspergillus spp. from lung tissue by culture or by histopathological methods; however, in clinical practice the decision to initiate antifungal therapy is more often based on immunological methods, such as the detection of Aspergillus-specific IgG antibodies from peripheral blood or galactomannan antigens from bronchoalveolar lavages. Acute IA or SIA infections have a high mortality and require immediate antifungal therapy. With rare exceptions CPA cannot be cured by medicinal therapy alone; however, active CPA can be brought into remission with antifungal therapy. Eradication of Aspergillus in CPA can as a rule only be successful using a combined antimycotic and surgical intervention.

Treatment of Aspergillosis

Infections caused by Aspergillus spp. remain associated with high morbidity and mortality. While mold-active antifungal prophylaxis has led to a decrease of occurrence of invasive aspergillosis (IA) in those patients most at risk for infection, breakthrough IA does occur and remains difficult to diagnose due to low sensitivities of mycological tests for IA. IA is also increasingly observed in other non-neutropenic patient groups, where clinical presentation is atypical and diagnosis remains challenging. Early and targeted systemic antifungal treatment remains the most important predictive factor for a successful outcome in immunocompromised individuals. Recent guidelines recommend voriconazole and/or isavuconazole for the primary treatment of IA, with liposomal amphotericin B being the first alternative, and posaconazole, as well as echinocandins, primarily recommended for salvage treatment. Few studies have evaluated treatment options for chronic pulmonary aspergillosis (CPA), where long-term oral itraconazole or voriconazole remain the treatment of choice.

Case Definition of Chronic Pulmonary Aspergillosis in Resource-Constrained Settings

Chronic pulmonary aspergillosis (CPA) is a recognized complication of pulmonary tuberculosis (TB). In 2015, the World Health Organization reported 2.2 million new cases of nonbacteriologically confirmed pulmonary TB; some of these patients probably had undiagnosed CPA. In October 2016, the Global Action Fund for Fungal Infections convened an international expert panel to develop a case definition of CPA for resource-constrained settings. This panel defined CPA as illness for >3 months and all of the following: 1) weight loss, persistent cough, and/or hemoptysis; 2) chest images showing progressive cavitary infiltrates and/or a fungal ball and/or pericavitary fibrosis or infiltrates or pleural thickening; and 3) a positive Aspergillus IgG assay result or other evidence of Aspergillus infection. The proposed definition will facilitate advancements in research, practice, and policy in lower- and middle-income countries as well as in resource-constrained settings.

Spotlight on isavuconazole in the treatment of invasive aspergillosis and mucormycosis: design, development, and place in therapy

In recent decades, important advances have been made in the diagnosis and treatment of invasive aspergillosis (IA) and mucormycosis. One of these advances has been the introduction of isavuconazole, a second-generation broad spectrum triazole with a favorable pharmacokinetic and safety profile and few drug–drug interactions. Phase III trials in patients with IA and mucormycosis demonstrated that isavuconazole has similar efficacy to voriconazole for the treatment of IA (SECURE trial) and liposomal amphotericin B for the treatment of mucormycosis (VITAL trial with subsequent case–control analysis) and a favorable safety profile with significantly fewer ocular, hepatobiliary, and skin and soft tissue adverse events compared to voriconazole. As a result, recent IA guidelines recommend isavuconazole (together with voriconazole) as gold standard treatment for IA in patients with underlying hematological malignancies. In contrast to liposomal amphotericin B, isavuconazole can be safely administered in patients with reduced renal function and is frequently used for the treatment of mucormycosis in patients with reduced renal function. Updated guidelines on mucormycosis are needed to reflect the current evidence and give guidance on the use of isavuconazole for mucormycosis. Studies are needed to evaluate the role of isavuconazole for 1) anti-mold prophylaxis in high-risk patients, 2) salvage treatment for IA and mucormycosis, and 3) treatment for other mold infections such as Scedosporium apiospermum.

Lateral Flow Assays for the Diagnosis of Invasive Aspergillosis: Current Status

PURPOSE OF REVIEW

Diagnosis during early stages of invasive aspergillosis (IA) and targeted antifungal treatment has the potential to improve survival significantly. Despite advances in the diagnostic arsenal, invasive mold infections remain difficult to diagnose-especially at early stages before typical radiological signs develop. Varying availability and time-to-results are important limitations of current approved biomarkers and molecular assays for diagnosis of IA. Here, we will give an update on the Aspergillus-specific lateral-flow device (LFD) test. We further review promising findings on feasibility of point-of-care (POC) detection of urinary excreted fungal galactomannan-like antigens.

RECENT FINDINGS

POC LFD assays for detection of Aspergillus antigens are currently in development. The Aspergillus-specific LFD test, which is based on the JF5 antibody (Ab), detects an extracellular glycoprotein antigen secreted during active growth of Aspergillus spp. The test has shown promising results in various studies. In addition, a monoclonal Ab476-based LFD for POC detection of urinary excreted fungal galactomannan-like antigens has been developed but needs further validation.

SUMMARY

Important advances have been made in the development of LFD assays for IA. Most promising is the Aspergillus-specific LFD test; commercial availability is still pending, however. The search for reliable POC tests for other molds, including mucorales, continues.

Diagnosis, classification, and therapeutic interventions for sinopulmonary Aspergillosis

INTRODUCTION

Sinopulmonary aspergillosis represents a diverse collection of allergic, invasive, and chronic sinus and respiratory conditions. These diseases can affect patients with and without immune impairment and in some cases may be life-threatening. Areas covered: We review the diagnosis, classification, and therapeutic options available to treat sinopulmonary aspergillosis and look ahead to emerging diagnostic and therapeutic options that may soon play an important role in clinical practice. Expert commentary: Histopathology and tissue culture remain the gold standard for the diagnosis of invasive sinopulmonary aspergillosis, but several new molecular detection methods have recently emerged, including various PCR-based platforms, MALDI-TOF, and lateral flow assays. We examine these methodologies as well as the barriers associated with the standardization, validation, and implementation. We also explore the pipeline of antifungal agents in development to treat sinopulmonary aspergillosis.

Factors affecting patient outcome in primary cutaneous aspergillosis

Primary cutaneous aspergillosis (PCA) is an uncommon infection of the skin. There is a paucity of organized literature regarding this entity in regard to patient characteristics, associated Aspergillus species, and treatment modalities on outcome (disease recurrence, disease dissemination, and mortality).We reviewed all published reports of PCA from 1967 to 2015. Cases were deemed eligible if they included the following: patient baseline characteristics (age, sex, underlying condition), evidence of proven or probable PCA, primary treatment strategy, and outcome.We identified 130 eligible cases reported from 1967 to 2015. The patients were predominantly male (63.8%) with a mean age of 30.4 ± 22.1 years. Rates of PCA recurrence, dissemination, and mortality were 10.8%, 18.5%, and 31.5%, respectively. In half of the cases, there was an association with a foreign body. Seven different Aspergillus species were reported to cause PCA. Systemic antifungal therapy without surgery was the most common form of therapy (60% of cases). Disease dissemination was more common in patients with underlying systemic conditions and occurred on average 41.4 days after PCA diagnosis (range of 3-120 days). In a multivariate linear regression model of mortality including only patients with immunosuppressive conditions, dissemination and human immunodeficiency virus/acquired immune deficiency syndrome were statistically significantly associated with increased mortality.Nearly one-third of patients with PCA die with the disease. Dissemination and host status are critical in patient outcome.