Pharmacodynamic monitoring by residual gene expression of the nuclear factor of activated T cell-regulated genes in lung transplant recipients and its correlation with tacrolimus blood levels.

Introduction: Trough blood levels (C0) of tacrolimus are used to adjust drug dosage, but they do not consistently correlate with clinical outcomes. Measurement of residual gene expression of nuclear factor of activated T cell (NFAT)-regulated genes (NFAT-RGE) has been proposed as a pharmacodynamic biomarker to assess the degree of immunosuppression in certain solid organ transplantations, but little is known regarding lung transplant recipients (LTR). Our primary objective is to correlate tacrolimus blood levels with NFAT-RGE. Methods: NFAT-RGE and tacrolimus C0 and peak (C1.5) levels were determined in 42 patients at three, six and 12 months post-transplantation. Results: Tacrolimus C0 did not exhibit a correlation with NFAT-RGE, whereas C1.5 did. Besides, over 20% of measurements indicated high levels of immunosuppression based on the below 30% NFAT-RGE threshold observed in many studies. Among those measurements within the therapeutic range, 19% had an NFAT-RGE<30%. Conclusion: Consequently, a subset of patients within the tacrolimus therapeutic range may be more susceptible to infection or cancer, potentially benefiting from NFAT-RGE and tacrolimus peak level monitoring to tailor their dosage. Further quantitative risk assessment studies are needed to elucidate the relationship between NFAT-RGE and the risk of infection, cancer, or rejection.

Mesenchymal stromal cell therapy for COVID-19 acute respiratory distress syndrome: a double-blind randomised controlled trial.

Mesenchymal stromal cells (MSC) have immunomodulatory and tissue-regenerative properties and have shown promising results in acute respiratory distress syndrome (ARDS) of multiple causes, including COVID-19. We conducted a randomised (1:1), placebo-controlled, double-blind clinical trial to assess the efficacy and safety of one bone marrow-derived MSC infusion in twenty patients with moderate to severe ARDS caused by COVID-19. The primary endpoint (increase in PaO2/FiO2 ratio from baseline to day 7, MSC 83.3 versus placebo 57.6) was not statistically significant, although a clinical improvement at day 7 in the WHO scale was observed in MSC patients (5, 50% vs 0, 0%, p = 0.033). Median time to discontinuation of supplemental oxygen was also shorter in the experimental arm (14 versus 23 days, p = 0.007), resulting in a shorter hospital stay (17.5 versus 28 days, p = 0.042). No significant differences were observed for other efficacy or safety secondary endpoints. No infusion or treatment-related serious adverse events occurred during the one-year follow-up. This study did not meet the primary endpoint of PaO2/FiO2 increase by day 7, although it suggests that MSC are safe in COVID-19 ARDS and may accelerate patients' clinical recovery and hospital discharge. Larger studies are warranted to elucidate their role in ARDS and other inflammatory lung disorders.Trial Registration: EudraCT Number: 2020-002193-27, registered on July 14th, 2020, https://www.clinicaltrialsregister.eu/ctr-search/trial/2020-002193-27/ES . NCT number: NCT04615429, registered on November 4th, 2020, https://clinicaltrials.gov/ct2/show/NCT04615429 .

Cytomegalovirus in the transplant setting: Where are we now and what happens next? A report from the International CMV Symposium 2021.

The CMV Symposium in September 2021 was an international conference dedicated to cytomegalovirus (CMV) infection after solid organ or hematopoietic stem cell transplantation. This review provides an overview of the presentations given by the expert faculty, supplemented with educational clinical cases. Topics discussed include CMV epidemiology and diagnosis, the burden of CMV infection and disease, CMV-specific immunity and management of CMV in transplant settings. Major advances in the prevention and treatment of CMV in the past decade and increased understanding of CMV immunity have led to improved patient outcomes. In the future, management algorithms may be individualized based on the transplant recipient's immune profile, which will mark the start of a new era for patients with CMV.

Evidence for shared genetic risk factors between lymphangioleiomyomatosis and pulmonary function.

INTRODUCTION: Lymphangioleiomyomatosis (LAM) is a rare low-grade metastasising disease characterised by cystic lung destruction. The genetic basis of LAM remains incompletely determined, and the disease cell-of-origin is uncertain. We analysed the possibility of a shared genetic basis between LAM and cancer, and LAM and pulmonary function. METHODS: The results of genome-wide association studies of LAM, 17 cancer types and spirometry measures (forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), FEV1/FVC ratio and peak expiratory flow (PEF)) were analysed for genetic correlations, shared genetic variants and causality. Genomic and transcriptomic data were examined, and immunodetection assays were performed to evaluate pleiotropic genes. RESULTS: There were no significant overall genetic correlations between LAM and cancer, but LAM correlated negatively with FVC and PEF, and a trend in the same direction was observed for FEV1. 22 shared genetic variants were uncovered between LAM and pulmonary function, while seven shared variants were identified between LAM and cancer. The LAM-pulmonary function shared genetics identified four pleiotropic genes previously recognised in LAM single-cell transcriptomes: ADAM12, BNC2, NR2F2 and SP5. We had previously associated NR2F2 variants with LAM, and we identified its functional partner NR3C1 as another pleotropic factor. NR3C1 expression was confirmed in LAM lung lesions. Another candidate pleiotropic factor, CNTN2, was found more abundant in plasma of LAM patients than that of healthy women. CONCLUSIONS: This study suggests the existence of a common genetic aetiology between LAM and pulmonary function.

Histamine signaling and metabolism identify potential biomarkers and therapies for lymphangioleiomyomatosis.

Inhibition of mTOR is the standard of care for lymphangioleiomyomatosis (LAM). However, this therapy has variable tolerability and some patients show progressive decline of lung function despite treatment. LAM diagnosis and monitoring can also be challenging due to the heterogeneity of symptoms and insufficiency of non-invasive tests. Here, we propose monoamine-derived biomarkers that provide preclinical evidence for novel therapeutic approaches. The major histamine-derived metabolite methylimidazoleacetic acid (MIAA) is relatively more abundant in LAM plasma, and MIAA values are independent of VEGF-D. Higher levels of histamine are associated with poorer lung function and greater disease burden. Molecular and cellular analyses, and metabolic profiling confirmed active histamine signaling and metabolism. LAM tumorigenesis is reduced using approved drugs targeting monoamine oxidases A/B (clorgyline and rasagiline) or histamine H1 receptor (loratadine), and loratadine synergizes with rapamycin. Depletion of Maoa or Hrh1 expression, and administration of an L-histidine analog, or a low L-histidine diet, also reduce LAM tumorigenesis. These findings extend our knowledge of LAM biology and suggest possible ways of improving disease management.

Heterogeneity and Cancer-Related Features in Lymphangioleiomyomatosis Cells and Tissue.

Lymphangioleiomyomatosis (LAM) is a rare, low-grade metastasizing disease characterized by cystic lung destruction. LAM can exhibit extensive heterogeneity at the molecular, cellular, and tissue levels. However, the molecular similarities and differences among LAM cells and tissue, and their connection to cancer features are not fully understood. By integrating complementary gene and protein LAM signatures, and single-cell and bulk tissue transcriptome profiles, we show sources of disease heterogeneity, and how they correspond to cancer molecular portraits. Subsets of LAM diseased cells differ with respect to gene expression profiles related to hormones, metabolism, proliferation, and stemness. Phenotypic diseased cell differences are identified by evaluating lumican (LUM) proteoglycan and YB1 transcription factor expression in LAM lung lesions. The RUNX1 and IRF1 transcription factors are predicted to regulate LAM cell signatures, and both regulators are expressed in LAM lung lesions, with differences between spindle-like and epithelioid LAM cells. The cancer single-cell transcriptome profiles most similar to those of LAM cells include a breast cancer mesenchymal cell model and lines derived from pleural mesotheliomas. Heterogeneity is also found in LAM lung tissue, where it is mainly determined by immune system factors. Variable expression of the multifunctional innate immunity protein LCN2 is linked to disease heterogeneity. This protein is found to be more abundant in blood plasma from LAM patients than from healthy women. IMPLICATIONS: This study identifies LAM molecular and cellular features, master regulators, cancer similarities, and potential causes of disease heterogeneity.

Predictive Value of Immune Cell Functional Assay for Non-Cytomegalovirus Infection in Lung Transplant Recipients: A Multicenter Prospective Observational Study.

INTRODUCTION: Immune cell functional assay (ImmuKnow®) is a non-invasive method that measures the state of cellular immunity in immunosuppressed patients. We studied the prognostic value of the assay for predicting non-cytomegalovirus (CMV) infections in lung transplant recipients. METHODS: A multicenter prospective observational study of 92 patients followed up from 6 to 12 months after transplantation was performed. Immune cell functional assay was carried out at 6, 8, 10, and 12 months. RESULTS: Twenty-three patients (25%) developed 29 non-CMV infections between 6 and 12 months post-transplant. At 6 months, the immune response was moderate (ATP 225-525ng/mL) in 14 (15.2%) patients and low (ATP<225ng/mL) in 78 (84.8%); no patients had a strong response (ATP≥525ng/mL). Only 1 of 14 (7.1%) patients with a moderate response developed non-CMV infection in the following 6 months compared with 22 of 78 (28.2%) patients with low response, indicating sensitivity of 95.7%, specificity of 18.8%, positive predictive value (PPV) of 28.2%, and negative predictive value (NPV) of 92.9% (AUC 0.64; p=0.043). Similar acute rejection rates were recorded in patients with mean ATP≥225 vs. <225ng/mL during the study period (7.1% vs. 9.1%, p=0.81). CONCLUSION: Although ImmuKnow® does not seem useful to predict non-CMV infection, it could identify patients with a very low risk and help us define a target for an optimal immunosuppression.

Correction: Lymphangioleiomyomatosis Biomarkers Linked to Lung Metastatic Potential and Cell Stemness.

[This corrects the article DOI: 10.1371/journal.pone.0132546.].

Monitoring of early humoral immunity to identify lung recipients at risk for development of serious infections: A multicenter prospective study.

BACKGROUND: Infection is still a leading cause of death during the first year after lung transplantation. We performed a multicenter study among teaching hospitals to assess monitoring of early humoral immunity as a means of identifying lung recipients at risk of serious infections. METHODS: We prospectively analyzed 82 adult lung recipients at 5 centers in Spain. Data were collected before transplantation and at 7 and 30 days after transplantation. Biomarkers included IgG, IgM, IgA, complement factors C3 and C4, titers of antibodies to pneumococcal polysaccharide antigens (IgG, IgA, IgM) and antibodies to cytomegalovirus (IgG), and serum B-cell activating factor (BAFF) levels. The clinical follow-up period lasted 6 months. Clinical outcomes were bacterial infections requiring intravenous anti-microbial agents, cytomegalovirus (CMV) disease, and fungal infections requiring therapy. RESULTS: We found that 33 patients (40.2%) developed at least 1 serious bacterial infection, 8 patients (9.8%) had CMV disease, and 10 patients (12.2%) had fungal infections. Lower IgM antibody levels against pneumococcal polysaccharide antigens at Day 7 (defined as <5 mg/dl) were a risk factor for serious bacterial infection (adjusted odds ratio [OR] 3.96; 95% confidence interval [CI] 1.39 to 11.26; p = 0.0099). At Day 7 after transplantation, IgG hypogammaglobulinemia (defined as IgG <600 mg/dl) was associated with a higher risk of CMV disease (after adjustment for CMV mismatch: OR 8.15; 95% CI 1.27 to 52.55; p = 0.028) and fungal infection (adjusted OR 8.03, 95% CI 1.51 to 42.72; p = 0.015). Higher BAFF levels before transplantation were associated with a higher rate of development of serious bacterial infection and acute cellular rejection. CONCLUSION: Early monitoring of specific humoral immunity parameters proved useful for the identification of lung recipients who are at risk of serious infections.

Lung cancer in lung transplantation: incidence and outcome.

INTRODUCTION: Malignancies are one of the causes of mortality after lung transplantation. However, little is known about lung cancer outcome after lung transplantation. METHODS: We performed a retrospective search of the lung transplantation database at our institution to identify patients diagnosed with lung cancer after lung transplantation. RESULTS: Out of 633 lung transplant patients, lung cancer was detected in 23 of them (3.63%). The most common causes for transplantation were idiopathic pulmonary fibrosis (47.8%) and emphysema (43.4%). A total of 18 patients were diagnosed during follow-up, 12 cases in the native lung (52.2%) and 6 cases in the donor lung (26.1%). The diagnosis was evidenced in the explanted lung in five patients (21.7%). The median of time from transplantation to cancer diagnosis was 39.7 months (24.356.6). Lung cancer was the cause of death in 16 patients. Survival rate at1year from diagnosis of lung cancer was 45.64% (95% CI 0.2431 to 0.6473). CONCLUSIONS: Lung transplant recipients constitute a high-risk group for developing lung cancer. Among our patients, lung cancer was predominantly diagnosed in the native lung and at an advanced stage. The primary tumour was the main cause of death in most of these patients.

Risk Factors for Clostridium Difficile Diarrhea in Patients With Solid Organ Transplantation.

BACKGROUND: There is limited knowledge about specific risk factors for Clostridium difficile infection (CDI). METHOD: A retrospective study comparing cases of CDI in solid organ transplant (SOT) recipients with controls (SOT recipients who did not present CDI). RESULTS: Thirty patients with SOT from 1340 transplantation recipients had at least 1 episode of CDI (2.23%). The accumulated incidence was 3.06% in liver transplantation, 2.78% in lung transplantation, 2.36% in kidney transplantation, and 0.33% in heart transplantation. Seven (23%) cases occurred during the first 2 months. Fifteen (50%) cases were community acquired. Colonoscopy was performed in 6 (20%) cases, but pseudomembranes were observed in only 1 (16%) case. Independent variables found to be related to CDI were previous treatment with proton pump inhibitors (PPIs; odds ratio [OR] 5.5; 95% confidence interval [CI] 1.2-32.0), immunosuppressive regimen including mycophenolate (OR 5.2; 95%CI 1.1-18), hospitalization during the previous 3 months (OR 5.1; 95%CI 1.1-17), and antibiotic treatment during the previous month (OR 6.7; 95%CI 1.4-23). Five (16.7%) patients did not respond to the initial treatment. Recurrences were noted in 6 (20%) patients. CONCLUSIONS: Liver transplant recipients presented the highest incidence. Risk factors for CDI were previous treatment with PPIs, immunosuppressive regimen containing mycophenolate, prior hospitalization, and prior antibiotic treatment.

Scedosporium apiospermum and S. prolificans mixed disseminated infection in a lung transplant recipient: An unusual case of long-term survival with combined systemic and local antifungal therapy in intensive care unit.

Infections due Scedosporium spp. in lung transplant recipients are associated with disseminated disease with high mortality rates. The adjunctive local antifungal therapy may be a useful option when systemic treatment is insufficient and/or surgery is not feasible. We present a case of mixed disseminated infection due Scedosporium apiospermum and S. prolificans in a lung transplant recipient. Combined local and systemic antifungal therapy provided an unusual long-term survival in the intensive care unit.

Study of breast cancer incidence in patients of lymphangioleiomyomatosis.

Molecular evidence has linked the pathophysiology of lymphangioleiomyomatosis (LAM) to that of metastatic breast cancer. Following on this observation, we assessed the association between LAM and subsequent breast cancer. An epidemiological study was carried out using three LAM country cohorts, from Japan, Spain, and the United Kingdom. The number of incident breast cancer cases observed in these cohorts was compared with the number expected on the basis of the country-specific incidence rates for the period 2000-2014. Immunohistochemical studies and exome sequence analysis were performed in two and one tumors, respectively. All cohorts revealed breast cancer standardized incidence ratios (SIRs) ≥ 2.25. The combined analysis of all cases or restricted to pre-menopausal age groups revealed significantly higher incidence of breast cancer: SIR = 2.81, 95 % confidence interval (CI) = 1.32-5.57, P = 0.009; and SIR = 4.88, 95 % CI = 2.29-9.99, P = 0.0007, respectively. Immunohistochemical analyses showed positivity for known markers of lung metastatic potential. This study suggests the existence of increased breast cancer risk among LAM patients. Prospective studies may be warranted to corroborate this result, which may be particularly relevant for pre-menopausal women with LAM.

Lymphangioleiomyomatosis Biomarkers Linked to Lung Metastatic Potential and Cell Stemness.

Lymphangioleiomyomatosis (LAM) is a rare lung-metastasizing neoplasm caused by the proliferation of smooth muscle-like cells that commonly carry loss-of-function mutations in either the tuberous sclerosis complex 1 or 2 (TSC1 or TSC2) genes. While allosteric inhibition of the mechanistic target of rapamycin (mTOR) has shown substantial clinical benefit, complementary therapies are required to improve response and/or to treat specific patients. However, there is a lack of LAM biomarkers that could potentially be used to monitor the disease and to develop other targeted therapies. We hypothesized that the mediators of cancer metastasis to lung, particularly in breast cancer, also play a relevant role in LAM. Analyses across independent breast cancer datasets revealed associations between low TSC1/2 expression, altered mTOR complex 1 (mTORC1) pathway signaling, and metastasis to lung. Subsequently, immunohistochemical analyses of 23 LAM lesions revealed positivity in all cases for the lung metastasis mediators fascin 1 (FSCN1) and inhibitor of DNA binding 1 (ID1). Moreover, assessment of breast cancer stem or luminal progenitor cell biomarkers showed positivity in most LAM tissue for the aldehyde dehydrogenase 1 (ALDH1), integrin-ß3 (ITGB3/CD61), and/or the sex-determining region Y-box 9 (SOX9) proteins. The immunohistochemical analyses also provided evidence of heterogeneity between and within LAM cases. The analysis of Tsc2-deficient cells revealed relative over-expression of FSCN1 and ID1; however, Tsc2-deficient cells did not show higher sensitivity to ID1-based cancer inhibitors. Collectively, the results of this study reveal novel LAM biomarkers linked to breast cancer metastasis to lung and to cell stemness, which in turn might guide the assessment of additional or complementary therapeutic opportunities for LAM.

The impact of the prevention strategies on the indirect effects of CMV infection in solid organ transplant recipients.

Transplant recipients receiving immunosuppressive therapy are at increased risk of active cytomegalovirus (CMV) infection and disease. Without appropriate prophylaxis, as many as 80% of solid organ transplant recipients may experience CMV infection. In addition to the direct effects of CMV, infection may be associated with a range of indirect effects, including an increase in risk of other infections, as well as a higher incidence of rejection, graft loss and death. The indirect effects of CMV infection can vary depending on the transplanted organ. For example, CMV-infected kidney transplant recipients may be at increased risk of cardiovascular disease and diabetes, while CMV infection in liver transplant recipients may potentiate hepatitis C infection and increase the risk of post-transplant lymphoproliferative disease. Indirect effects result from a number of pathological processes, including immune modulation and immunosuppression, generation of cytotoxic, pro-inflammatory responses, and smooth muscle proliferation. Prophylactic treatment with antiviral medication can reduce the risk of CMV disease, thereby improving graft survival and overall outcomes, particularly in kidney and heart transplant recipients. Antiviral prophylaxis should be considered for all patients at risk of CMV infection after solid organ transplantation. In this paper we review the main indirect effects of CMV infection in solid organ transplant recipients, and the impact of CMV prophylaxis on these effects.

New concepts and best practices for management of pre- and post-transplantation cancer.

Solid-organ transplant recipients are at increased risk of developing cancer compared with the general population. Tumours can arise de novo, as a recurrence of a preexisting malignancy, or from the donated organ. The ATOS (Aula sobre Trasplantes de Órganos Sólidos; the Solid-Organ Transplantation Working Group) group, integrated by Spanish transplant experts, meets annually to discuss current advances in the field. In 2011, the 11th edition covered a range of new topics on cancer and transplantation. In this review we have highlighted the new concepts and best practices for managing cancer in the pre-transplant and post-transplant settings that were presented at the ATOS meeting. Immunosuppression plays a major role in oncogenesis in the transplant recipient, both through impaired immunosurveillance and through direct oncogenic activity. It is possible to transplant organs obtained from donors with a history of cancer as long as an effective minimization of malignancy transmission strategy is followed. Tumour-specific wait-periods have been proposed for the increased number of transplantation candidates with a history of malignancy; however, the patient's individual risk of death from organ failure must be taken into consideration. It is important to actively prevent tumour recurrence, especially the recurrence of hepatocellular carcinoma in liver transplant recipients. To effectively manage post-transplant malignancies, it is essential to proactively monitor patients, with long-term intensive screening programs showing a reduced incidence of cancer post-transplantation. Proposed management strategies for post-transplantation malignancies include viral monitoring and prophylaxis to decrease infection-related cancer, immunosuppression modulation with lower doses of calcineurin inhibitors, and addition of or conversion to inhibitors of the mammalian target of rapamycin.

Clinical lung transplantation from uncontrolled non-heart-beating donors revisited.

BACKGROUND: The aim of our study is to review and update the long-term results from our previously published series of lung transplantation in uncontrolled non-heart-beating donors (NHBDs). METHODS: A prospective collection of data was undertaken from all lung transplants performed among uncontrolled NHBDs between 2002 and December 2009. The statistical analysis was performed using SPSS software and survival was estimated using the Kaplan-Meier method. RESULTS: Twenty-nine lung transplants were performed. Mean total ischemic times for the first and second lung were 575 minutes (SD 115.6) and 701 minutes (SD 111.3), respectively. Primary graft dysfunction (PGD) G1, G2 and G3 occurred in 5 cases (17%), 5 cases (17%) and 11 cases (38%), respectively. Overall hospital mortality rate was 17% (5 patients). Statistical analysis revealed a statistically significant association of mortality with ischemic times and with PGD. In terms of overall survival, 3-month, 1-year, 2-year and 5-year survival rates were 78%, 68%, 57% and 51%, respectively, and the conditional survival rates in those who survived the first 3 months were 86%, 72% and 65%, respectively. The cumulative incidence of bronchiolitis obliterans syndrome (BOS) was 11%, 35% and 45% at 1, 3 and 5 years, respectively. CONCLUSIONS: Lung transplantation from uncontrolled non-heart-beating donors shows acceptable results for both mid- and long-term survival and BOS; however, the higher rates of PGD and its impact on early mortality must make us more demanding with respect to the acceptance criteria and methods of evaluation used with these donors.

Recommendations for management of Chagas disease in organ and hematopoietic tissue transplantation programs in nonendemic areas.

The substantial immigration into Spain from endemic areas of Chagas disease such as Latin America has increased the number of potential donors of organs and tissues. In addition, an increasing number of patients with advanced Chagas heart disease may eventually be eligible to receive a heart transplant, a universally accepted therapeutic strategy for the advanced stages of this disease. Therefore, it is necessary to establish protocols for disease management. This document is intended to establish the guidelines to be followed when a potential donor or a tissue or organ recipient is potentially affected by Chagas disease and summarizes the action criteria against the possibility of Chagas disease transmission through the donation of organs, tissues, or hematopoietic stem cells and aims to help professionals working in this field. A single registry of transplants in Trypanosoma cruzi infected donors and/or recipients will provide and disseminate experience in this area, which has shown a low recorded incidence to date.

Nebulized liposomal amphotericin B prophylaxis for Aspergillus infection in lung transplantation: pharmacokinetics and safety.

BACKGROUND: The main problem with using nebulized liposomal amphotericin (n-LAB) as prophylaxis for Aspergillus infection after lung transplantation is the lack of knowledge of its pharmacokinetics and its possible adverse effects. The aim of this study was to measure post-inhalation amphotericin B concentration in the respiratory tract and serum of lung transplant patients and assess the effects of n-LAB on respiratory function. METHODS: Thirty-two consecutive bronchoscopies were performed on 27 lung transplant patients at two hospitals. Amphotericin B concentration in the first and third aliquot of bronchoalveolar lavage material was measured in steady state. The first aliquot approximates most closely the true amphotericin B concentrations in the proximal airway, whereas the third aliquot provides an optimum sample from the distal airway. RESULTS: At 2 days, mean amphotericin B concentrations were 11.1 microg/ml (95% confidence interval [CI]: 16.5 to 5.7 microg/ml) and 9.0 microg/ml (95% CI: 14.3 to 3.8 microg/ml) in the first and third aliquot, respectively. Thereafter, concentrations declined progressively. At 14 days, concentrations were 3.0 microg/ml (95% CI: 4.4 to 1.5 microg/ml) in the first aliquot and 4.1 microg/ml (95% CI: 6.1 to 2.1 microg/ml) in the third aliquot (p = not statistically significant). Traces of amphotericin B (0.1 microg/ml) were found in serum samples from only 1 of 27 patients. Mean value of forced expiratory volume in the first second (FEV(1)) was similar before and after n-LAB. CONCLUSIONS: Amphotericin B concentrations after n-LAB remained high for 14 days, at adequate concentrations for prophylaxis of Aspergillus infection. No significant systemic absorption of amphotericin B was detected and no effect was observed on respiratory function. This promising prophylactic regimen warrants assessment in future clinical studies.