Is there still a place for serum galactomannan in the diagnosis of invasive aspergillosis in children at high risk and under antifungal prophylaxis?

BACKGROUND: The performance of serum galactomannan (GM) for the diagnosis of invasive aspergillosis (IA) has been studied mainly in adults. Paediatric data are scarce and based on small and heterogeneous cohorts. OBJECTIVE: To evaluate the performance of serum GM for the diagnosis of IA in a paediatric oncologic population at high risk of IA and to clarify the impact of antifungal prophylaxis on this test. METHODS: We performed a retrospective study from January 2014 to December 2020 in the paediatric oncologic haematologic department of the University Hospital of Bordeaux. The diagnosis of IA was made using the recommendations of the EORTC and the MSGERC. RESULTS: Among the 329 periods at high risk of IA in 222 patients, the prevalence of IA was 1.8% (3 proven and 3 probable IA). In the total population, the sensitivity, and the positive predictive value (PPV) were respectively 50% and 17.6%. Under antifungal prophylaxis, the sensitivity and PPV dropped, respectively, to 33.3% and 14.3%. In this group, the post-test probability of IA was 2% for a negative serum GM and only 14%. CONCLUSION: In this large cohort of children at high risk of IA, the incidence of IA is low and the diagnostic performance of GM is poor, especially in the case of mould-active prophylaxis. Screening should be targeted rather than systematic and should be reserved for patients at highest risk for IA without mould-active prophylaxis. Combination with other tests such as Aspergillus PCR would increase the accuracy of GM in screening setting.

Micafungin twice-a-week for prophylaxis of invasive Aspergillus infections in children with acute lymphoblastic leukaemia: A controlled cohort study.

OBJECTIVES: Invasive Aspergillus infections during the early phase of childhood acute lymphoblastic leukemia (ALL) treatment come with morbidity and mortality. The interaction with vincristine hampers first-line azole prophylaxis. We describe the efficacy of an alternative twice-a-week micafungin regimen for Aspergillus prophylaxis. METHODS: Newly diagnosed paediatric patients with ALL treated according to the ALL-11 protocol received micafungin twice-a-week (9 mg/kg/dose [max. 300 mg]) during the induction course (first 35 days of treatment) as part of routine care. A historical control cohort without Aspergillus prophylaxis was used. During the first consolidation course (day 36-79), standard itraconazole prophylaxis was used in both groups. The percentage of proven/probable Aspergillus infections during the induction/first consolidation course was compared between the cohorts. The cumulative incidence of proven/probable Aspergillus infections was estimated using a competing risk model. For safety evaluation, liver laboratory chemistry values were analysed. RESULTS: A total of 169 and 643 paediatric patients with ALL were treated in the micafungin cohort (median age: 4 years [range 1-17]) and historical cohort (median age: 5 years [range 1-17]). The percentage of proven/probable Aspergillus infections was 1·2% (2/169) in the micafungin cohort versus 5·8% (37/643) in the historical cohort (p=0.013; Fisher's exact test). The differences in estimated cumulative incidence were assessed (p=0·014; Gray's test). Although significantly higher ALT/AST values were reported in the micafungin cohort, no clinically relevant side effects were observed. CONCLUSIONS: Twice-a-week micafungin prophylaxis during the induction course significantly reduced the occurrence of proven/probable Aspergillus infections in the early phase of childhood ALL treatment.

Posaconazole exposure in critically ill ICU patients: a need for action.

PURPOSE: Posaconazole is an antifungal drug currently being used for prophylaxis and treatment of invasive fungal infections such as aspergillosis. To date, therapeutic drug monitoring (TDM) of posaconazole is recommended with the use of oral suspension, but the potential need of TDM with the use of IV formulations is rising. Therefore, we aimed to investigate the pharmacokinetics of IV posaconazole in critically ill patients. METHODS: In a prospective study, we analysed 168 consecutivelly collected posaconazole levels from 10 critically ill patients drawn during a 7 day curse. Posaconazole concentrations were measured using a chromatographic method. Demographic and laboratory data were collected, and the data was analysed using descriptive statistics. RESULTS: We included 168 posaconazole levels, resulting in a median trough of 0.62 [0.29-1.05] mg/L with 58% not reaching the suggested target of 0.5 mg/L for fungal prophylaxis. Moreover, 74% of the trough levels were under the target of 1 mg/L which is proposed for the treatment of aspergillosis. CONCLUSION: Posaconazole exposure is highly variable in critically ill patients resulting in potentially insufficient drug concentrations in many cases. TDM is highly recommended to identify and avoid underexposure. TRIAL REGISTRATION NUMBER: NCT05275179, March 11, 2022.

Statin Use May Be Associated With a Lower Risk of Invasive Aspergillosis in Lung Transplant Recipients.

BACKGROUND: Statins are competitive inhibitors of 3-hydroxy-3methylglutaryl coenzyme A reductase (HMG-CoA reductase) that catalyses HMG-CoA conversion to mevalonate, a process involved in synthesizing cholesterol in humans and ergosterol in fungi. The effect of statin use on the risk of development of invasive aspergillosis (IA) in lung transplant recipients (LTRs) is not well documented. METHODS: This retrospective study included LTRs from 2010 to 2017 who were followed for one-year post-transplant. Proven or probable IA was diagnosed as per ISHLT criteria. We performed a multivariable Cox proportional hazards model of the association between IA and statin use (minimum of 2 weeks duration prior to IA), adjusting for other known IA risk factors. RESULTS: We identified 785 LTRs, 44% female, mean age 53 years old, the most common underlying disease being pulmonary fibrosis (23.8%). In total, 451 LTRs (57%) received statins post-transplant, atorvastatin was the most commonly used statin (68%). The mean duration of statins post-transplant was 347 days (interquartile range [IQR]: 305 to 346). And 55 (7%) LTRs developed IA in the first-year post-transplant. Out of these 55 LTRs, 9 (16.3%) had received statin before developing IA. In multivariable analysis, statin use was independently associated with a lower risk of IA (P = .002, SHR 0.30, 95% confidence interval [CI] 95% .14-.64). Statin use was also associated with a lower incidence of post-transplant Aspergillus colonization, 114 (34%) in the no statin group vs 123 (27%) in the statin group (P = .038). CONCLUSIONS: The use of statin for a minimum of two weeks during the first-year post-transplant was associated with a 70% risk reduction of IA in LTRs.

[Countermeasures Against Aspergillosis in Captive Penguins].

Aspergillosis is a major fungal infection in humans and animals. Penguins (Order Spheniscidae) are particularly susceptible to aspergillosis, and aspergillosis in captive penguins is presently a major problem. We were faced with the challenge of combating aspergillosis in an aquarium. As a solution, we organized a multidisciplinary aspergillosis control team, including a medical and veterinary mycologist. Since Aspergillus, including Aspergillus fumigatus, is abundant in soil, we thought it necessary to minimize contact between captive penguins and soil to prevent aspergillosis. As a countermeasure, we stopped using a route for outdoor penguin marches where the soil was exposed. Additionally, after outdoor penguin marches, the feet of penguins were washed with seawater to avoid bringing soil into the rearing facility for penguins. Furthermore, since A. fumigatus was detected on several spots in the environment of the rearing facility by swab analysis, we cleaned and sanitized the rearing facility with 0.02% sodium hypochlorite and hot water. As a result of the above measures, there has been no incidence of aspergillosis in captive penguins since 2016. These results show that our preventive measures are working well. As shown here, we presented an example of how the multidisciplinary control team, which included a mycologist, successfully implemented preventive measures against aspergillosis. Due to changes in the rearing environment and the impact of global warming on penguins, it is expected that the role of mycologists in aspergillosis control will expand in the future.

Recombinant Aspergillus fumigatus antigens Asp f 3 and Asp f 9 in liposomal vaccine protect mice against invasive pulmonary aspergillosis.

Invasive pulmonary aspergillosis caused by the ubiquitous mold Aspergillus fumigatus is a major threat to immunocompromised patients, causing unacceptably high mortality despite standard of care treatment, and costing an estimated $1.2 billion annually. Treatment for this disease has been complicated by the emergence of azole resistant strains of A. fumigatus, rendering first-line antifungal therapy ineffective. The difficulties in treating infected patients using currently available drugs make immunotherapeutic vaccination an attractive option. Here, we demonstrate the efficacy of VesiVax® adjuvant liposomes, consisting of a combination of two individual liposome preparations, to which two recombinant A. fumigatus surface antigens, Asp f 3 and Asp f 9 (VesiVax® Af3/9), have been chemically conjugated. Using a murine model, we demonstrate that VesiVax® Af3/9 is protective against infection by azole resistant strains of A. fumigatus in both steroid-suppressed and neutropenic mice as quantified by improved survival and reduced fungal burden in the lungs. This protection correlates with upregulation of IL-4 produced by splenocytes, and the presence of Asp f 3 and Asp f 9 specific IgG2a antibodies in the serum of mice given VesiVax® Af3/9. Furthermore, mice given VesiVax® Af3/9 with a subsequent course of liposomal amphotericin B (AmBisome®) had improved survival over those given either treatment alone, indicating a benefit to VesiVax® Af3/9 vaccination even in the case of infections that require follow-up antifungal treatment. These data demonstrate that prophylactic vaccination with VesiVax® Af3/9 is a promising method of protection against invasive pulmonary aspergillosis even as the changing face of the disease renders current therapies ineffective.

Assessment of the Safety and Efficacy of an Oral Probiotic-Based Vaccine Against Aspergillus Infection in Captive-Bred Humboldt Penguins (Spheniscus humboldti).

Aspergillosis is a fungal infection caused mainly by Aspergillus fumigatus that often results in respiratory disease in birds. Aspergillosis is a major cause of morbidity and mortality in captive-bred penguin species. Currently, there is no registered vaccine to prevent aspergillosis. Recent research demonstrated that oral administration of gram-negative bacteria expressing high levels of galactose-α-1,3-galactose (α-Gal) modulates anti-α-Gal immunity and protects turkeys from clinical aspergillosis caused by experimental A. fumigatus infection. The role of anti-α-Gal immunity in penguins has not been studied. Here, we tested the distribution of α-1,3-galactosyltransferase (α1,3GT) genes in the fecal microbiome of Humboldt penguins (Spheniscus humboldti). The occurrence of natural anti-α-Gal antibodies (Abs) in sera and eggs of healthy Humboldt penguins was also assessed. A trial was then conducted to test whether oral administration of Escherichia coli Nissle, expressing high α-Gal levels, modulates anti-α-Gal immunity in a colony of Humboldt penguins. Animals in the vaccination and placebo groups were evaluated before the trial and followed for one year for aspergillosis detection using a diagnostic panel including computed tomography scans, capillary zone electrophoresis, 3-hydroxybutyrate levels, and anti-A. fumigatus Abs. Anti-α-Gal Abs were detected in sera (IgM and IgY) and eggs (IgY) of healthy penguins. Microbiota analysis and functional predictions revealed the presence of α1,3GT genes in the microbiota of Humboldt penguins and other penguin species. A strong decrease in anti-α-Gal IgM levels was observed in all animals in the placebo group three months after vaccination protocol. This decrease was not observed in E. coli Nissle-treated penguins. After the vaccination protocol, we found a positive correlation between anti-E. coli IgY and anti-α-Gal IgY in the E. coli Nissle group, suggesting a correlation between the presence of the bacteria and these Abs. During the study period, three penguins exhibited respiratory signs consistent with aspergillosis. Two were from the placebo group whose symptoms resolved with specific treatments, while a single vaccinated individual developed fatal respiratory aspergillosis eight months after the trial. We conclude that E. coli Nissle represents a safe potential probiotic with a protective effect against aspergillosis in Humboldt penguins that deserves to be further explored for therapeutic uses in these animals.

Resolvin D1 protects against Aspergillus fumigatus keratitis in diabetes by blocking the MAPK-NF-κB pathway.

Fungal keratitis (FK) is one of the main causes of blindness in China. People with diabetes are susceptible to corneal epithelial disease, even fungal keratitis. At present, there are few studies on this disease. Resolvins (Rv) has been reported as a mediators that exert crucial anti-inflammatory and immune regulation roles in serval diseases. In order to investigate the roles and underlying mechanism of Resolvins D1 (RvD1) on the Aspergillus fumigatus (A. fumigatus) keratitis in diabetes, we established in vivo and in vitro models of A. fumigatus keratitis, which were then exposed to high glucose. The expression levels of RvD1, 5-lipoxygenase (5-LOX), and 15-lipoxygenase (15-LOX) in A. fumigatus keratitis patients with diabetes were determined through Enzyme Linked Immunosorbent Assay (ELISA), Western blot and immunohistochemistry. Reactive Oxygen Species (ROS) production, ELISA, flow cytometry, Hematoxylin-Eosin (HE) staining and fungal loading determination were conducted to evaluate the severity of A. fumigatus infection. Lymphangiogenesis and angiogenesis were examined by immunofluorescence assay. Western blot was applied to detect the proteins of the MAPK-NF-κB pathway. The results showed that RvD1 diminished the high glucose-induced oxidative stress and inflammatory response, as evidenced by the reduction of ROS production, Interleukin-6 (IL-6), Interleukin-8 (IL-8), Heme Oxygenase-1 (HMOX-1), and the elevation of Cyclooxygenase-2 (COX2), Superoxide Dismutase (SOD-1), and Glutathione Peroxidase-2 (GPX2) levels in A. fumigatus-infected Human Corneal Endothelial Cells (HCECs). Additionally, lymphangiogenesis and angiogenesis prominently decreased after intervention with RvD1. Furthermore, RvD1 significantly reduced the levels of p-MEK1/2 and p-ERK1/2, and restrained the NF-κB and GPR32 activation. The above results showed that RvD1 protects against A. fumigatus keratitis in diabetes by suppressing oxidative stress, inflammatory response, fungal growth, and immunoreaction via modulating MAPK-NF-κB pathway. RvD1 provides clues for the therapeutic targets of Fungal keratitis complicated with diabetes.

Weekly high-dose liposomal amphotericin B prevents invasive aspergillosis after heart transplantation.

BACKGROUND: Preventive strategies for invasive aspergillosis (IA) have still not been determined in heart transplant recipients whereas IA leads to a high mortality rate at 12 months posttransplantation. The use of voriconazole or echinocandins was proposed but can favor emergence of Aspergillus or Candida sp. resistant strains or promote neurological and liver disorders in some patients. OBJECTIVES: To assess whether universal prophylaxis with weekly high-dose of liposomal amphotericin-B (L-AmB) can safely prevent IA in heart transplant recipients. PATIENTS/METHODS: Retrospective before/after study that included 142 patients who received heart transplantation between 2010 and 2019 at the University Hospital of Toulouse (France). Weekly high dose of L-AmB (7.5 mg/kg/week) was used as universal prophylaxis from 2016 because of high environmental exposure to Aspergillus sp. and high incidence of IA. RESULTS: Cumulative 1-year incidence of IA decreased from 23% to 5% after introduction of L-Amb prophylaxis. Multivariate analysis (Cox model) identified L-AmB prophylaxis as a protective factor against IA (hazard ratio [HR] 0.21 [95% confidence interval 0; 0.92], p = .04), whereas postoperative renal replacement therapy was associated with IA (HR 3.6 [95% confidence interval 1.38; 9.3], p = .001), after correction for confounding effects (induction regimen, methylprednisolone pulses and history of hematological malignancy). The incidence of acute kidney injury requiring renal replacement therapy was similar in the two groups, suggesting a low risk of kidney toxicity when L-AmB is used weekly. No patient developed severe kidney electrolyte loss nor L-AmB-related anaphylaxis. CONCLUSIONS: Once-weekly high-dose L-AmB is safe and may prevent the development of IA after heart transplantation.

Aspergillus flavus Infections in Children With Leukemia Despite Liposomal Amphotericin-B Prophylaxis.

Liposomal amphotericin-B (L-AmB) prophylaxis is used in children with leukemia when azoles are contraindicated, but its effect is debated. We reviewed cases of invasive aspergillosis despite L-AmB 2.5 mg/kg twice weekly in children with high-risk leukemia during 2012-2019. Ten (16%) of 62 children had proven or probable aspergillosis. Thus, L-AmB prophylaxis offered insufficient protection for Aspergillus, in particular for Aspergillus flavus.

The Pathogenesis of Aspergillus fumigatus, Host Defense Mechanisms, and the Development of AFMP4 Antigen as a Vaccine.

Aspergillus fumigatus is one of the ubiquitous fungi with airborne conidia, which accounts for most aspergillosis cases. In immunocompetent hosts, the inhaled conidia are rapidly eliminated. However, immunocompromised or immunodeficient hosts are particularly vulnerable to most Aspergillus infections and invasive aspergillosis (IA), with mortality from 50% to 95%. Despite the improvement of antifungal drugs over the last few decades, the therapeutic effect for IA patients is still limited and does not provide significant survival benefits. The drawbacks of antifungal drugs such as side effects, antifungal drug resistance, and the high cost of antifungal drugs highlight the importance of finding novel therapeutic and preventive approaches to fight against IA. In this article, we systemically addressed the pathogenic mechanisms, defense mechanisms against A. fumigatus, the immune response, molecular aspects of host evasion, and vaccines' current development against aspergillosis, particularly those based on AFMP4 protein, which might be a promising antigen for the development of anti-A. fumigatus vaccines.

Invasive aspergillosis in solid organ transplant patients: diagnosis, prophylaxis, treatment, and assessment of response.

BACKGROUND: Invasive aspergillosis (IA) is a rare complication in solid organ transplant (SOT) recipients. Although IA has significant implications on graft and patient survival, data on diagnosis and management of this infection in SOT recipients are still limited. METHODS: Discussion of current practices and limitations in the diagnosis, prophylaxis, and treatment of IA and proposal of means of assessing treatment response in SOT recipients. RESULTS: Liver, lung, heart or kidney transplant recipients have common as well as different risk factors to the development of IA, thus each category needs a separate evaluation. Diagnosis of IA in SOT recipients requires a high degree of awareness, because established diagnostic tools may not provide the same sensitivity and specificity observed in the neutropenic population. IA treatment relies primarily on mold-active triazoles, but potential interactions with immunosuppressants and other concomitant therapies need special attention. CONCLUSIONS: Criteria to assess response have not been sufficiently evaluated in the SOT population and CT lesion dynamics, and serologic markers may be influenced by the underlying disease and type and severity of immunosuppression. There is a need for well-orchestrated efforts to study IA diagnosis and management in SOT recipients and to develop comprehensive guidelines for this population.

Small Molecule CCR4 Antagonists Protect Mice from Aspergillus Infection and Allergy.

The ability to regulate the recruitment of immune cells makes chemokines and their receptors attractive drug targets in many inflammatory diseases. Based on its preferential expression on T helper type 2 (Th2) cells, C-C chemokine receptor type 4 (CCR4) has been widely studied in the context of allergic diseases, but recent evidence on the expression of CCR4 in other cell types has considerably expanded the potential applications of CCR4 antagonism. However, the current number of approved indications, as well as the portfolio of CCR4-targeting drugs, are still limited. In the present study, we have assessed the potential therapeutic efficacy of a CCR4 small molecule antagonist, SP50, discovered via an in silico-based approach, against a variety of pre-clinical settings of infection with the fungus Aspergillus fumigatus. We show that SP50 efficiently worked as prophylactic vaccine adjuvant in immunocompetent mice, protected against invasive aspergillosis in immunosuppressed mice. Further, the CCR4 antagonist prevented allergic bronchopulmonary aspergillosis in susceptible mice, and in a murine model of cystic fibrosis, a genetic disorder characterized by chronic pulmonary inflammation and recurrent infections. In conclusion, our results extend the potential applications of CCR4 antagonism and prompt for the development of novel compounds with the potential to progress to clinical trials.

Targeted caspofungin prophylaxis for invasive aspergillosis in high-risk liver transplant recipients, a single-center experience.

BACKGROUND: Invasive aspergillosis (IA) is a rare but highly lethal complication after orthotopic liver transplantation (OLT). Targeted antifungal prophylaxis has been proposed as a strategy to prevent IA among orthotopic liver transplant recipient (OLTr), but limited data are available to support its efficacy. METHOD: We conducted a single-center, retrospective, before and after cohort study, comparing IA incidences among OLTr who did not receive antifungal prophylaxis after transplantation (cohort 1) to OLTr who received targeted antifungal prophylaxis after liver transplantation (cohort 2). Patients in cohort 2 received caspofungin prophylaxis if they presented one of the following risk factors: retransplantation, acute liver failure, dialysis, or Aspergillus colonization prior to transplantation. The primary outcome was IA at 90 days after transplantation. RESULTS: A total of 391 OLTr were included in the study; 181 patients in the cohort 1 (no prophylaxis) and 210 patients in the cohort 2 (targeted prophylaxis). Among patients in cohort 2, 19% (40/ 210) were considered at high risk for IA and 85% (34/40) of those received caspofungin prophylaxis. The incidence of IA at 90 days was 3.3% (6/ 181) and 0.5% (1/ 210), in cohort 1 and 2, respectively (OR 0.14; 95%CI 0.01-0.83; P = .03). Ninety-day mortality was similar among the two cohorts (3.9% (7/181) and 2.4% (5/210) in cohort 1 and 2, respectively (OR 0.61; 95% 0.18-1.93; P = .40)). The 90-day mortality among the OLTs with IA was 71% (5/7). CONCLUSION: Targeted caspofungin prophylaxis was associated with lower rate of IA.

Nebulized Amphotericin B Dosing Regimen for Aspergillus Prevention After Lung Transplant.

OBJECTIVES: Lung transplant guidelines recommend nebulized amphotericin B with or without systemic antifungal agents for fungal prophylaxis. However, amphotericin formulation, dosing, and frequency vary between studies. We assessed the safety and effectiveness of nebulized amphotericin B to prevent Aspergillus infection in 2 regimens, ie, twice daily compared with 3 times daily. MATERIALS AND METHODS: This was a single-center retrospective cohort study. We included patients at least 14 years old who underwent lung transplant and received nebulized amphotericin B alone or in combination with another antifungal agent either twice daily or 3 times daily. The primary endpoint was the incidence of lung Aspergillus infection, and the secondary endpoints were nebulized amphotericin B side effects and breakthrough Aspergillus infection. RESULTS: A total of 84 patients were included. The group given nebulized amphotericin twice daily had a higher rate of Aspergillus infection at 17% compared with 4% in the group treated 3 times daily (P = .24). No serious side effects were reported, but coughing and diarrhea were more common in patients who received amphotericin B 3 times daily. CONCLUSIONS: A systemic antifungal agent combined with nebulized amphotericin either twice or 3 times daily has been effective to prevent Aspergillus infection. Nebulized amphotericin twice daily may be a more viable option to increase a patient's adherence and decrease medication cost and side effects. However, a larger randomized controlled trial is needed to determine the best dosing regimen for nebulized amphotericin B as a fungal prophylaxis after lung transplant.