Incidence and outcomes of invasive fungal infection among solid organ transplant recipients: A population-based cohort study

Design, Synthesis, Investigation, and Biological Activity Assessments of (4-Substituted-Phenyl)-N-(3-morpholinopropyl)-3-phenylthiazol-2(3H)-imine Derivatives as Antifungal Agents

In this study, a series of novel thiazol-2(3H)-imine (2a-2j) were designed, synthesized, and characterized by means of 1H NMR, 13C NMR, and HRMS spectral analyses. In vitro antifungal activity was performed using a modified EUCAST protocol. Two of the synthesized compounds (2d and 2e) showed activity against Candida albicans and Candida parapsilosis. Compound 2e showed activity against C. parapsilosis (MIC50 = 1.23 μg/mL) for 48 h. This value is very similar to ketoconazole. The dynamic analysis of the potential compounds 2d and 2e revealed notable stability while interacting with the 14α-demethylase enzyme substrate. The absorption, distribution, metabolism, and excretion (ADME) studies of the candidate compound showed acceptable ADME parameter data and verified their drug-likeness characteristics. According to the results of this study, compound 4-(4-fluorophenyl)-N-(3-morpholinopropyl)-3-phenylthiazol-2(3H)-imine (2e) and its derivatives as 14α-demethylase inhibitors can be used as a new antifungal for further structural improvements and additional research.

Antifungal prophylaxis against invasive Candida and Aspergillus infection in adult heart transplant recipients: protocol for a systematic review and meta-analysis

INTRODUCTION

Invasive fungal infections (IFI) can contribute to increased mortality and morbidity rates after heart transplant in adults. The most common causes are Aspergillus and Candida species. There is uncertainty on how effective antifungal prophylaxis is against Candida spp infections and limited guidance on the prevention of Aspergillus spp infections. This systematic review and meta-analysis will assess the literature to see if antifungal prophylaxis reduces the incidence of IFI after heart transplant in adults.

METHODS AND ANALYSIS

This systematic review protocol follows the Preferred Reporting Items for Systematic reviews and Meta Analysis guidelines. A systematic search of the Cochrane Library, Web of Science, Scopus, Embase, MEDLINE, and Proquest databases will be undertaken. Reference lists of retrieved publications and conference abstracts will also be searched. Title, abstract and full-text screening will be undertaken by two reviewers. Discrepancies will be resolved by a third reviewer. Studies with paediatric patients, multi-organ transplants, or patients with a second heart transplant will be excluded, along with those who do not have clear definitions and diagnostic criteria for IFI. Risk of bias will be assessed using the Cochrane Risk of Bias 2 tool and the Risk of Bias in Non-randomised Studies of Interventions tool. A meta-analysis will be carried out, but if studies are not deemed to be sufficiently similar, only a narrative synthesis will be undertaken.

ETHICS AND DISSEMINATION

Ethical approval is not required for this systematic review as primary data will not be collected. The results of the review will be disseminated through publication in an academic journal and scientific conferences.

PROSPERO REGISTRATION NUMBER

CRD42024516588.

Increase in the incidence of invasive fungal infections due to Volvariella Volvacea

PURPOSE

We aimed to show the increasing incidence of invasive fungal infections due to Volvariella Volvacea in patients with immunosuppression.

METHODS

We present a case of an invasive fungal infection caused by Volvariella volvacea, and summarize the clinical and pathological features based on this case and a review of the literature.

RESULTS

A total of seven patients with IFIs due to Volvariella Volvacea have been reported in the literature. The majority of cases have been obtained between 2019 and 2022. Including our case, they all had acquired immunosuppression. The lung and brain were the most commonly affected organs. All eight of these patients received antifungal therapy, but five still died one to seven months after occurrences of IFIs.

CONCLUSION

The incidence of invasive fungal infections due to Volvariella Volvacea is increasing in recent years. It mainly occurred in patients with immunosuppression, especially in patients with malignant hematological cancers, and increased mortality.

ERS International Congress 2023: highlights from the Thoracic Surgery and Lung Transplantation Assembly

Five sessions presented at the European Respiratory Society Congress 2023 were selected by Assembly 8, consisting of thoracic surgeons and lung transplant professionals. Highlights covering management of adult spontaneous pneumothorax, malignant pleural effusion, infectious and immune-mediated complications after lung transplantation, as well as the pro and con debate on age limit in lung transplantation and results of the ScanCLAD study were summarised by early career members, supervised by the assembly faculty.

Infection-Related Hospitalizations After Simultaneous Pancreas-Kidney Transplantation Compared to Kidney Transplantation Alone

The total burden of infections after transplantation has not been compared in detail between recipients of simultaneous pancreas-kidney transplantation (SPK) and kidney transplantation alone (KTA). We compared infection-related hospitalizations and bacteremias after transplantation during 1- and 5-year follow-up among 162 patients undergoing SPK. The control group consisted of 153 type 1 diabetics undergoing KTA with the inclusion criteria of donor and recipient age < 60, and BMI < 30. During the first year, SPK patients had more infection-related hospitalizations (0.54 vs. 0.31 PPY, IRR 1.76, p = <0.001) and bacteremias (0.11 vs. 0.01 PPY, IRR 17.12, p = <0.001) compared to KTA patients. The first infection-related hospitalizations and bacteremias occurred later during follow-up in KTA patients. SPK was an independent risk factor for infection-related hospitalization and bacteremia during the first year after transplantation, but not during the 5-year follow-up. Patient survival did not differ between groups, however, KTA patients had inferior kidney graft survival. SPK patients are at greater risk for infection-related hospitalizations and bacteremias during the first year after transplantation compared to KTA patients, however, at the end of the follow-up the risk of infection was similar between groups.

Fungal Infections and Colonization after Bilateral Lung Transplant: A Six-Year Single-Center Experience

Fungal infections (FIs) are one of the leading causes of morbidity and mortality within the first year of lung transplant (LT) in LT recipients (LTRs). Their prompt identification and treatment are crucial for a favorable LTR outcome. The objectives of our study were to assess (i) the FI incidence and colonization during the first year after a bilateral LT, (ii) the risk factors associated with FI and colonization, and (iii) the differences in fungal incidence according to the different prophylactic strategies. All bilateral LTRs admitted to the intensive care unit of Padua University Hospital were retrospectively screened, excluding patients <18 years of age, those who had been re-transplanted, and those who had received ventilation and/or extracorporeal membrane oxygenation before LT. Overall, 157 patients were included. A total of 13 (8%) patients developed FI, and 36 (23%) developed colonization, which was mostly due to Aspergillus spp. We did not identify independent risk factors for FI. Groups of patients receiving different prophylactic strategies reported a similar incidence of both FI and colonization. The incidence of FI and fungal colonization was 8% and 23%, respectively, with no differences between different antifungal prophylaxes or identified predisposing factors. Further studies with larger numbers are needed to confirm our results.

Natural history and prognostic factors of candidemia in kidney transplant recipients: A retrospective, multinational study

BACKGROUND

The natural history of candidemia in kidney transplant recipients (KTR) remains poorly understood. This study aimed to evaluate mortality, prognostic factors and overall graft loss after candidemia in KTRs.

METHODS

This is a retrospective multicentre study enrolling all KTRs ≥15 years old with candidemia diagnosed at hospitals in Brazil, Spain and Italy from 2010 to 2020. Primary endpoints were mortality rates at 14 and 30 days. Secondary endpoints were prognostic factors of 14-day mortality and overall graft loss.

RESULTS

We enrolled 93 KTRs of which 75 were from Brazil. The mean time interval from transplantation to the onset of candidemia was 45.2 ± 61.5 months. 42% of all patients were on haemodialysis, 31.3% had an episode of sepsis and 39% underwent surgery within 30 days before fungemia. European patients were more likely to receive echinocandin (32 vs. 72%, p < .001). 22.7% of Brazilian patients did not receive any antifungal before death. All-cause mortality at 14 days was higher in Brazil (41.3 vs. 11.1%, p = .016). Candida colonisation (OR 6.91 [95% CI: 1.08-44.3], p = .042) and hypotension (OR 4.87 [95% CI: 1.62-14.66], p = .005) were associated with 14-day mortality. Echinocandin treatment had a protective effect (OR 0.19 [95% CI: 0.05-0.73], p = .015). Graft loss at 90 days occurred in 48% of patients (70.7 in Brazil vs. 22.2% in Europe, p < .01).

CONCLUSIONS

Candidemia in KTR is usually documented late after engraftment in patients requiring HD, surgical procedures and dysbiosis secondary to antibiotic use. Mortality was higher in Brazil. Echinocandin therapy was associated with improved survival.

Modulatory immune responses in fungal infection associated with organ transplant - advancements, management, and challenges

Organ transplantation stands as a pivotal achievement in modern medicine, offering hope to individuals with end-stage organ diseases. Advancements in immunology led to improved organ transplant survival through the development of immunosuppressants, but this heightened susceptibility to fungal infections with nonspecific symptoms in recipients. This review aims to establish an intricate balance between immune responses and fungal infections in organ transplant recipients. It explores the fundamental immune mechanisms, recent advances in immune response dynamics, and strategies for immune modulation, encompassing responses to fungal infections, immunomodulatory approaches, diagnostics, treatment challenges, and management. Early diagnosis of fungal infections in transplant patients is emphasized with the understanding that innate immune responses could potentially reduce immunosuppression and promise efficient and safe immuno-modulating treatments. Advances in fungal research and genetic influences on immune-fungal interactions are underscored, as well as the potential of single-cell technologies integrated with machine learning for biomarker discovery. This review provides a snapshot of the complex interplay between immune responses and fungal infections in organ transplantation and underscores key research directions.

Culture-independent diagnostic approaches for invasive aspergillosis in solid organ transplant recipients

Prompt and accurate diagnosis of invasive aspergillosis (IA) is crucial for immunocompromised patients, including those who have received a solid organ transplant (SOT). Despite their low sensitivity, microscopic detection and conventional culture are considered the 'gold standard' methods. In conjunction with conventional culture, culture-independent assays such as serum galactomannan testing and Aspergillus polymerase chain reaction (PCR) have been incorporated into the diagnostic process for IA. The recently revised consensus definitions from the European Organization for Research and Treatment of Cancer and the Mycosis Study Group have adjusted the threshold for positive galactomannan testing based on the sample type, and have excluded 1,3-β-D-glucan testing as a mycological criterion. Following extensive standardization efforts, positive Aspergillus PCR tests using serum, plasma, or bronchoalveolar lavage fluid have been added. However, there are limited studies evaluating the clinical utility of these culture-independent assays for the early diagnosis of IA in SOT recipients. Therefore, further research is required to determine whether these assays could aid in the early diagnosis of IA in SOT recipients, particularly in relation to the organ transplanted. In this review, we examine the culture-independent diagnostic methods for IA in SOT recipients, as well as the clinical utility of these assays.

Part 1: Mucormycosis: Prevalence, Risk Factors, Clinical Features and Diagnosis

INTRODUCTION

Mucormycosis (MCR) is caused by filamentous molds within the Class Zygomycetes and Order Mucorales. Infections can result from inhalation of spores into the nares, oropharynx or lungs, ingestion of contaminated food or water, or inoculation into disrupted skin or wounds. In developed countries, MCR occurs primarily in severely immunocompromised hosts. In contrast, in developing/low income countries, most cases of MCR occur in persons with poorly controlled diabetes mellitus and some cases in immunocompetent subjects following trauma. Mucormycosis exhibits a propensity to invade blood vessels, leading to thrombosis and infarction of tissue. Mortality rates associated with invasive MCR are high and can exceed 90% with disseminated disease. Mucormycosis can be classified as one of six forms: (1) rhino-orbital-cerebral mucormycosis (ROCM); (2) pulmonary; (3) cutaneous; (4) gastrointestinal or renal (5); disseminated; (6) uncommon (focal) sites.

AREAS COVERED

The authors discuss the prevalence, risk factors and clinical features of mucormycosis.A literature search of mucormycosis was performed via PubMed (up to November 2022), using the key words: invasive fungal infections; mold; mucormycosis; Mucorales; Zyzomyces; Zygomycosis; Rhizopus, diagnosis.

EXPERT OPINION

Mucormycosis occurs primarily in severely immunocompromised hosts. Mucormycosis can progress rapidly, and delay in initiating treatment by even a few days worsens outcomes.

Nanoparticle-Based Photodynamic Inhibition of Candida albicans Biofilms with Interfering Quorum Sensing

Biofilm formation is a critical event in the pathogenesis and virulence of fungal infections caused by Candida albicans, giving rise to about a 1000-fold increase in the resistance to antifungal agents. Although photodynamic treatment (PDT) has been excellently implicated in bacterial infections, studies on its potential against fungal infection through the clearance of fungal biofilm formation remain at its infancy stage. Here, we have designed photodynamic nanoparticles with different sizes, modifications, and the ability of generating reactive oxygen species (ROS) to examine their effects on inhibiting biofilm formation and destructing mature biofilms of C. albicans. We found that the nanoparticles modified with oligo-chitosan exhibited a better binding efficiency for planktonic cells, leading to stronger inhibitory efficacy of the filamentation and the early-stage biofilm formation. However, for mature biofilms, the nanoparticles with the smallest size (∼15 nm) showed the fastest penetration speed and a pronounced destructing effect albeit conferring the lowest ROS-producing capability. The inhibitory effect of photodynamic nanoparticles was dependent on the disruption of fungal quorum sensing (QS) by the upregulation of QS molecules, farnesol and tyrosol, mediated through the upregulation of ARO 8 and DPP 3 expression. Our findings provide a powerful strategy of nanoparticulate PDT to combat fungal infections through the inhibition of both hyphal and biofilm formation by disrupting QS.

Non-Aspergillus mould lung infections

Non-Aspergillus filamentous fungi causing invasive mould infections have increased over the last years due to the widespread use of anti-Aspergillus prophylaxis and increased complexity and survival of immunosuppressed patients. In the few studies that have reported on invasive mould infection epidemiology, Mucorales are the most frequently isolated group, followed by either Fusarium spp. or Scedosporium spp. The overall incidence is low, but related mortality is exceedingly high. Patients with haematological malignancies and haematopoietic stem cell transplant recipients comprise the classical groups at risk of infection for non-Aspergillus moulds due to profound immunosuppression and the vast use of anti-Aspergillus prophylaxis. Solid organ transplant recipients also face a high risk, especially those receiving lung transplants, due to direct exposure of the graft to mould spores with altered mechanical and immunological elimination, and intense, associated immunosuppression. Diagnosing non-Aspergillus moulds is challenging due to unspecific symptoms and radiological findings, lack of specific biomarkers, and low sensitivity of cultures. However, the advent of molecular techniques may prove helpful. Mucormycosis, fusariosis and scedosporiosis hold some differences regarding clinical paradigmatic presentations and preferred antifungal therapy. Surgery might be an option, especially in mucormycosis. Finally, various promising strategies to restore or enhance the host immune response are under current evaluation.

Antifungal stewardship in solid organ transplantation

BACKGROUND

Antifungal stewardship (AFS) has emerged as an important component of quality in managing invasive fungal infections (IFIs), and cost-benefit calculations suggest regular training in AFS is well worth the effort.

METHODS

This review will discuss the most common IFIs in solid organ transplantation (SOT)-recipients, how to diagnose them, and current recommendations for antifungal treatment and prophylaxis before demonstrating key takeaway points of AFS in this high-risk population.

RESULTS

Effective AFS starts before a patient is admitted for SOT, through education and regular interactions of the interdisciplinary clinical team involved in patient management, considering local factors such as epidemiological data and knowledge of diagnostic options including local turnaround times. Understanding the spectrum of antifungal agents, their efficacy and safety profiles, and pharmacokinetics, as well as duration of therapy is hereby essential. The most frequent IFIs in SOT recipients are caused by Candida species, followed by Aspergillus species, both with increasing resistance rates. Diagnosis of IFI can be challenging due to unspecific clinical presentation and difficult interpretation of microbiological findings and biomarkers. Prophylactic strategies, such as those for invasive aspergillosis in lung transplantation or invasive candidiasis (IC) in certain liver transplant settings, as well as the selection of the appropriate therapeutic agents require detailed knowledge on the pharmacokinetics and drug-drug interactions of antifungals.

CONCLUSIONS

Here in this review, we address what constitutes good AFS in this heterogeneous field of solid organ transplant recipients.

Efficacy of Anti-fungal Agents for Invasive Fungal Infection prophylaxis in Liver Transplant Recipients: A Network Meta-Analysis

At present, there is still a lack of effective invasive fungal prophylaxis therapy in liver transplant recipients (LTRs). This study aimed to analysis the latest evidence on efficacy of current prophylactic anti-fungal therapy, and systematically compare between anti-fungal agents and placebo by a fixed-effects meta-analysis in all randomized controlled trials. A network meta-analysis was performed for invasive fungal infection (IFI) among different agents in 14 randomized controlled trials, in which 10 anti-fungal approaches were identified. Overall, anti-fungal prophylaxis reduced the rate of IFI (RR 0.30, 95% CI 0.18-0.52) and proven IFI (RR 0.27, 95% CI 0.14-0.53) when compared to placebo. In the network meta-analysis, an equivalent reduction in the rate of IFI was observed in fluconazole (OR 4.70, 95% CI 1.22-18.10), itraconazole (OR 5.82, 95% CI 1.10-30.71) and Liposomal amphotericin B (LAmB, OR 5.74, 95% CI 1.29-25.58) groups when compared with placebo. Anidulafungin might be the most effective agents in IFI prevention, however, this superiority did not meet statistically significance. Our study indicated that fluconazole, echinocandins and LAmB are equivalent in efficacy. Of which, fluconazole is recommended for the prevention of IFI in LTRs due to its efficacy, economics and compliance.

Bring it on: Top five antimicrobial stewardship challenges in transplant infectious diseases and practical strategies to address them

Antimicrobial therapies are essential tools for transplant recipients who are at high risk for infectious complications. However, judicious use of antimicrobials is critical to preventing the development of antimicrobial resistance. Treatment of multidrug-resistant organisms is challenging and potentially leads to therapies with higher toxicities, intravenous access, and intensive drug monitoring for interactions. Antimicrobial stewardship programs are crucial in the prevention of antimicrobial resistance, though balancing these strategies with the need for early and frequent antibiotic therapy in these immunocompromised patients can be challenging. In this review, we summarize 5 frequently encountered transplant infectious disease stewardship challenges, and we suggest strategies to improve practices for each clinical syndrome. These 5 challenging areas are: asymptomatic bacteriuria in kidney transplant recipients, febrile neutropenia in hematopoietic stem cell transplantation, antifungal prophylaxis in liver and lung transplantation, treatment of left-ventricular assist device infections, and Clostridioides difficile infection in solid-organ and hematopoietic stem-cell transplant recipients. Common themes contributing to these challenges include limited data specific to transplant patients, shortcomings in diagnostic testing, and uncertainties in pharmacotherapy.

Development and evaluation of a novel fast broad-range PCR and sequencing assay (FBR-PCR/S) using dual priming oligonucleotides targeting the ITS/LSU gene regions for rapid diagnosis of invasive fungal diseases: multi-year experience in a large Canadian healthcare zone

Background

This study evaluated the performance of a novel fast broad range PCR and sequencing (FBR-PCR/S) assay for the improved diagnosis of invasive fungal disease (IFD) in high-risk patients in a large Canadian healthcare region.

Methods

A total of 114 clinical specimens (CS) including bronchoalveolar lavages (BALs) were prospectively tested from 107 patients over a 2-year period. Contrived BALs (n = 33) inoculated with known fungi pathogens were also tested to increase diversity. Patient characteristics, fungal stain and culture results were collected from the laboratory information system. Dual-priming oligonucleotide (DPO) primers targeted to the internal transcribed spacer (ITS) (~ 350 bp) and large subunit (LSU) (~ 550 bp) gene regions were used to perform FBR-PCR/S assays on extracted BALs/CS. The performance of the molecular test was evaluated against standard microbiological methods and clinical review for the presence of IFD.

Results

The 107 patients were predominantly male (67, 62.6%) with a mean age of 59 years (range = 0–85 years): 74 (69.2%) patients had at least one underlying comorbidity: 19 (34.5%) had confirmed and 12 (21.8%) had probable IFD. Culture recovered 66 fungal isolates from 55 BALs/CS with Candida spp. and Aspergillus spp. being most common. For BALs, the molecular assay vs. standard methods had sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV), and efficiency of 88.5% vs.100%, 100% vs. 61.1%, 100% vs. 88.5%, 61.1% vs. 100%, and 90.2% for both. For other CS, the molecular assay had similar performance to standard methods with sensitivity, specificity, PPV, NPV and efficiency of 66.7%, 87.0%, 66.7%, 87.0% and 81.3% for both methods. Both methods also performed similarly, regardless of whether CS stain/microscopy showed yeast/fungal elements. FBR-PCR/S assays results were reported in ~ 8 h compared to fungal cultures that took between 4 and 6 weeks.

Conclusions

Rapid molecular testing compared to standard methods have equivalent diagnostic efficiency but improves clinical utility by reporting a rapid species-level identification the same dayshift (~ 8 h).

Antifungal prophylaxis in adult lung transplant recipients: Uncertainty despite 30 years of experience. A systematic review of the literature and network meta-analysis

BACKGROUND

Invasive fungal infections (IFI), particularly invasive aspergillosis (IA), cause significant morbidity and mortality in lung transplant (LTx) recipients. The optimum strategy and antifungal agents for prevention are unclear.

METHODS

We performed a comprehensive literature search, systematic review, and network meta-analysis using a frequentist framework to compare the efficacy of various antifungal drugs on the incidence of IA/IFI in the setting of universal prophylaxis or no prophylaxis following lung transplantation.

RESULTS

We included 13 eligible studies comprising of 1515 LTx recipients and 12 different prophylaxis strategies/antifungal combinations. The greatest number of direct comparisons were between the inhaled amphotericin formulations. The top three ranked treatments were inhaled liposomal amphotericin B (L-AmB), inhaled amphotericin deoxycholate (AmBd), and itraconazole plus inhaled amphotericin B (AmB). Among the azoles, isavuconazole ranked highest. The certainty of the evidence, assessed using the GRADE (Grading of Recommendations Assessment, Development and Evaluation) framework, was very low.

CONCLUSION

Although universal antifungal prophylaxis post lung transplantation is commonly used, robust data from randomized controlled trials (RCTs) to inform the choice of antifungal agent and prophylaxis strategy are lacking. This exploratory network meta-analysis provides insight into the probable relative effectiveness of various antifungal agents in preventing IA, and this analysis should serve as a guide when selecting antifungals to be assessed in a RCT.

Population Pharmacokinetics of Caspofungin and Dose Simulations in Heart Transplant Recipients

The effect of heart transplantation (HTx) on the pharmacokinetics (PK) of caspofungin is not well-characterized. The aim of this study was to investigate the population PK of caspofungin in HTx and non-HTx patients and to identify covariates that may affect the PK of caspofungin. Seven successive blood samples were collected before administration and at 1, 2, 6, 10, 16, and 24 h after the administration of caspofungin for at least 3 days. This study recruited 27 HTx recipients and 31 non-HTx patients with 414 plasma concentrations in total. A nonlinear mixed-effects model was used to describe the population PK of caspofungin. The PK of caspofungin was best described by a two-compartment model. The clearance (CL) and volume of the central compartment (V_c) of caspofungin were 0.385 liter/h and 4.27 liters, respectively. The intercompartmental clearance (Q) and the volume of the peripheral compartment (V_p) were 2.85 liters/h and 6.01 liters, respectively. In the final model, we found that albumin (ALB) affected the CL of caspofungin with an adjustment factor of -1.01, and no other covariates were identified. In this study, HTx was not found to affect the PK of caspofungin. Based on the simulations, the dose of caspofungin should be proportionately increased in patients with decreased ALB levels.

Fungal infections in lung transplantation

Lung transplant is a potential life-saving procedure for chronic lung diseases. Lung transplant recipients (LTRs) are at the greatest risk for invasive fungal infections (IFIs) among solid organ transplant (SOT) recipients because the allograft is directly exposed to fungi in the environment, airway and lung host defenses are impaired, and immunosuppressive regimens are particularly intense. IFIs occur within a year of transplant in 3-19% of LTRs, and they are associated with high mortality, prolonged hospital stays, and excess healthcare costs. The most common causes of post-LT IFIs are Aspergillus and Candida spp.; less common pathogens are Mucorales, other non-Aspergillus moulds, Cryptococcus neoformans, Pneumocystis jirovecii, and endemic mycoses. The majority of IFIs occur in the first year following transplant, although later onset is observed with prolonged antifungal prophylaxis. The most common manifestations of invasive mould infections (IMIs) include tracheobronchial (particularly at anastomotic sites), pulmonary and disseminated infections. The mortality rate of tracheobronchitis is typically low, but local complications such as bronchomalacia, stenosis and dehiscence may occur. Mortality rates associated with lung and disseminated infections can exceed 40% and 80%, respectively. IMI risk factors include mould colonization, single lung transplant and augmented immunosuppression. Candidiasis is less common than mould infections, and manifests as bloodstream or other non-pulmonary invasive candidiasis; tracheobronchial infections are encountered uncommonly. Risk factors for and outcomes of candidiasis are similar to those of non lung transplant recipients. There is evidence that IFIs and fungal colonization are risk factors for allograft failure due to chronic rejection. Mould-active azoles are frontline agents for treatment of IMIs, with local debridement as needed for tracheobronchial disease. Echinocandins and azoles are treatments for invasive candidiasis, in keeping with guidelines in other patient populations. Antifungal prophylaxis is commonly administered, but benefits and optimal regimens are not defined. Universal mould-active azole prophylaxis is used most often. Other approaches include targeted prophylaxis of high-risk LTRs or pre-emptive therapy based on culture or galactomannan (GM) (or other biomarker) results. Prophylaxis trials are needed, but difficult to perform due to heterogeneity in local epidemiology of IFIs and standard LT practices. The key to devising rational strategies for preventing IFIs is to understand local epidemiology in context of institutional clinical practices.

A Large Sample Retrospective Study on the Distinction of Voriconazole Concentration in Asian Patients from Different Clinical Departments

Voriconazole (VRZ) is widely used to prevent and treat invasive fungal infections; however, there are a few studies examining the variability and influencing the factors of VRZ plasma concentrations across different clinical departments. This study aimed to evaluate distinction of VRZ concentrations in different clinical departments and provide a reference for its reasonable use. From 1 May 2014 to 31 December 2020, VRZ standard rates and factors affecting the VRZ trough concentration were analyzed, and a multiple linear regression model was constructed. The standard rates of VRZ in most departments were above 60%. A total of 676 patients with 1212 VRZ trough concentrations using a dosing regimen of 200 mg q12h from seven departments were enrolled in the correlation analysis. The concentration distribution varied significantly among different departments (p < 0.001). Fifteen factors, including department, CYP2C19 phenotype, and gender, correlated with VRZ concentration. A multiple linear regression model was established as follows: VRZ trough concentration = 5.195 + 0.049 × age + 0.007 × alanine aminotransferase + 0.010 × total bilirubin − 0.100 × albumin − 0.004 × gamma-glutamyl transferase. According to these indexes, we can predict possible changes in VRZ trough concentration and adjust its dosage precisely and individually.

Fungal infections following liver transplantation

With increasing morbidity and mortality from chronic liver disease and acute liver failure, the need for liver transplantation is on the rise. Most of these patients are extremely vulnerable to infections as they are immune-compromised and have other chronic co-morbid conditions. Despite the recent advances in practice and improvement in diagnostic surveillance and treatment modalities, a major portion of these patients continue to be affected by post-transplant infections. Of these, fungal infections are particularly notorious given their vague and insidious onset and are very challenging to diagnose. This mini-review aims to discuss the incidence of fungal infections following liver transplantation, the different fungi involved, the risk factors, which predispose these patients to such infections, associated diagnostic challenges, and the role of prophylaxis. The population at risk is increasingly old and frail, suffering from various other co-morbid conditions, and needs special attention. To improve care and to decrease the burden of such infections, we need to identify the at-risk population with more robust clinical and diagnostic parameters. A more robust global consensus and stringent guidelines are needed to fight against resistant microbes and maintain the longevity of current antimicrobial therapies.

Risk factors of invasive fungal infections in lung transplant recipients: A systematic review and meta-analysis

BACKGROUND

Invasive fungal infection (IFI) remains a common complication after lung transplantation, causing significant morbidity and mortality. We have attempted to quantify systematically risk factors of IFI in lung transplant recipients.

METHODS

Studies were retrieved from Ovid MEDLINE, Ovid Embase, Cochrane database of systematic reviews and Cochrane central register of controlled trials. All case-control and cohort studies evaluating the risk factors of IFI in adult lung transplant recipients were screened. Two researchers reviewed and assessed all studies independently. We pooled the estimated effect of each factor associated with IFI by using a random effect model.

RESULTS

Eight studies were included in the systematic review and 5 studies were eligible for the meta-analysis. Rates of IFI range from 8% to 33% in lung transplant recipients. Independent risk factors for invasive aspergillosis (IA) in lung transplantation include previous fungal colonization (odds ratio [OR] 2.44; 95% confidence interval [CI] 0.08-0.47), cytomegalovirus infection (OR 1.96; 95% CI 1.08-3.56), and single lung transplantation (OR 1.77; 95% CI 1.08-2.91). Pre-emptive antifungal therapy is a protective factor for IA in lung transplant (OR 0.2; 95% CI 0.08-0.47).

CONCLUSION

Cytomegalovirus infection, previous fungal colonization and single lung transplantation independently increase the risk of IA in lung transplant recipients. Pre-emptive antifungal therapy is a protective factor for IA in the lung transplant population.

Emerging of Fatal Colitis with Multidrug-Resistant Candida glabrata after Small Bowel Transplantation

Background

Small bowel transplantation is a potential option for patients with intestinal-failure, and the incidences of infections caused by Candida species that are more resistant to antifungal drugs are increasing in these patients. In this manuscript, we reported a case of fatal colitis after small bowel transplantation induces by multidrug-resistant (MDR) Candida glabrata. Case Presentation. A 52-year-old man has undergone an extensive small bowel resection with the length of the remaining bowel which was less than 40 cm who became a candidate for transplantation. Four months after transplantation, the patient experienced severe bloody diarrhea with abdominal distension. Ileoscopy and colonoscopy did not show neither pathological change and rejection nor cytomegalovirus (CMV) infection posttransplantation. Abdomen computed tomography showed diffuse moderate small bowel wall thickening. After detection of budding yeast in the stool samples, stool culture was positive for Candida, DNA was extracted, and ITS1-5.8s-ITS2 region of the fungal agent was amplified. Sequencing analysis of PCR and antifungal susceptibility testing revealed that this isolate was multidrug-resistant C. glabrata. Besides, there was no evidence for other pathogens known to cause infection in various laboratory tests. Immediate antifungal treatments with caspofungin remained unsuccessful, and on the eighteenth day of admission, the patient expires with septic shock.

Conclusion

These findings highlight the challenging management of candidiasis in patients with small bowel transplantation. Infectious diseases due to MDR organisms have emerged as a vital clinical problem in this patient population.

Epidemiology, risk factors, and association of antifungal prophylaxis on early invasive fungal infection in heart transplant recipients

BACKGROUND

Invasive fungal infection (IFI) in heart transplant recipients is associated with poor outcomes. Estimated risk of 1-year IFI in heart transplant recipients is 3.4-8.6% with risk factors inconsistently identified in previous studies. The role of antifungal prophylaxis is unclear. The transplant program at Mayo Clinic provides 6 months of universal azole prophylaxis for those heart transplant recipients in Arizona. We sought to define risk factors for 1-year IFI and determine the effect of antifungal prophylaxis.

METHODS

We conducted a retrospective cohort study of patients undergoing heart transplantation at Mayo Clinic from January 2000 to March 2019. We analyzed demographics, details of transplant hospitalization, antifungal prophylaxis, and fungal infection. Multivariable Cox analyses were performed to identify risk factors of 1-year IFI and impact of IFI on posttransplant mortality.

RESULTS

A total of 966 heart transplant recipients were identified with a median age of 56 years (IQR 47, 62). A total of 444 patients received antifungal prophylaxis. Over 1-year follow-up, 62 patients developed IFI with a cumulative incidence of 6.4%. In multivariable analysis, factors associated with IFI were renal replacement therapy (RRT) (HR 3.24, 95% CI 1.65-6.39), allograft rejection (HR 2.33, 95% CI 1.25-4.34), and antifungal prophylaxis (HR 0.32, 95% CI 0.11-0.96). RRT was also associated with invasive mold infection (HR 3.00, 95% CI 1.29-6.97).

CONCLUSIONS

RRT and allograft rejection after transplantation are associated with 1-year IFI, and RRT is also associated with invasive mold infection. Antifungal prophylaxis appears to be protective and further study is needed in the heart transplant population.

Breakthrough invasive fungal infections in liver transplant recipients exposed to prophylaxis with echinocandins vs other antifungal agents: A systematic review and meta-analysis

INTRODUCTION

Although echinocandins are recommended as first-line prophylaxis for high-risk orthotopic liver transplant (OLT) recipients, occurrence of breakthrough-invasive fungal infections (IFIs) remains a serious concern. We aim to assess the risk of breakthrough IFIs among OLT recipients exposed to prophylaxis with echinocandins compared to other antifungals.

MATERIALS AND METHODS

Two authors independently searched PubMed-MEDLINE, Embase, study registries and reference lists from inception to March 2021, to retrieve randomised controlled trials (RCTs) or observational studies comparing efficacy and safety of echinocandins vs other antifungals for prophylaxis in OLT recipients. Data were independently extracted from two authors, and the quality of included studies was independently assessed according to ROB 2.0 tool for RCTs and ROBINS-I tool for observational studies. The primary outcome was occurrence of breakthrough IFI at the end of prophylaxis (EOP).

RESULTS

698 articles were screened, and ten studies (3 RCTs and 7 observational) were included. No difference between echinocandins and other antifungals in terms of breakthrough IFIs at the EOP emerged both from RCTs (odds ratio [OR] 0.85, 95% CI 0.24-2.99) and observational studies (OR 1.43, 95% CI 0.28-7.40). No difference emerged also for secondary outcomes. In the subgroup comparison between echinocandins and polyenes, a trend for higher risk of breakthrough IFI at the EOP (OR 4.82, 95% CI 0.97-24.03) was noted.

CONCLUSIONS

Echinocandins do not seem to be associated with increased risk of breakthrough IFIs in OLT recipients. However, the large diversity in the comparator group hinders a definitive interpretation. Further studies exploring the relationship between echinocandin use and breakthrough IFIs according to specific comparators are warranted.

Isavuconazole Is as Effective as and Better Tolerated Than Voriconazole for Antifungal Prophylaxis in Lung Transplant Recipients

BACKGROUND

Invasive fungal infections (IFIs) are common following lung transplantation. Isavuconazole is unstudied as prophylaxis in organ transplant recipients. We compared effectiveness and tolerability of isavuconazole and voriconazole prophylaxis in lung transplant recipients.

METHODS

A single-center, retrospective study of patients who received isavuconazole (September 2015-February 2018) or voriconazole (September 2013-September 2015) for antifungal prophylaxis. IFIs were defined by EORTC/MSG criteria.

RESULTS

Patients received isavuconazole (n = 144) or voriconazole (n = 156) for median 3.4 and 3.1 months, respectively. Adjunctive inhaled amphotericin B (iAmB) was administered to 100% and 41% of patients in the respective groups. At 1 year, 8% of patients receiving isavuconazole or voriconazole developed IFIs. For both groups, 70% and 30% of IFIs were caused by molds and yeasts, respectively, and breakthrough IFI (bIFI) rate was 3%. Outcomes did not significantly differ for patients receiving or not receiving iAmB. Independent risk factors for bIFI and breakthrough invasive mold infection (bIMI) were mold-positive respiratory culture and red blood cell transfusion >7 units at transplant. Bronchial necrosis >2 cm from anastomosis and basiliximab induction were also independent risk factors for bIMI. Isavuconazole and voriconazole were discontinued prematurely due to adverse events in 11% and 36% of patients, respectively (P = .0001). Most common causes of voriconazole and isavuconazole discontinuation were hepatotoxicity and lack of oral intake, respectively. Patients receiving ≥90 days prophylaxis had fewer IFIs at 1 year (3% vs 9%, P = .02). IFIs were associated with increased mortality (P = .0001) and longer hospitalizations (P = .0005).

CONCLUSIONS

Isavuconazole was effective and well tolerated as antifungal prophylaxis following lung transplantation.

Gastrointestinal Histoplasmosis Mimicking Crohn's Disease

Disseminated histoplasmosis is a life-threatening disease usually seen in immunocompromised patients living in endemic areas. We present an apparently immunocompetent patient with gastrointestinal histoplasmosis who was initially diagnosed with biopsy-proven Crohn's disease. Following discontinuation of anti-inflammatory drugs and institution of antifungal therapy, his gastrointestinal illness completely improved. Specific fungal staining should be routinely included in histopathologic assessment of tissue specimens diagnosed as Crohn's disease.

Fungal Infections in Liver Transplant Recipients

Invasive fungal infections (IFIs) are one of the most feared complications associated with liver transplantation, with high rates of morbidity and mortality. We discuss the most common invasive fungal infections in the setting of liver transplant, including Candida, Aspergillus, and Cryptococcal infections, and some less frequent but devastating mold infections. Further, we evaluate the use of prophylaxis to prevent invasive fungal infection in this population as a promising mechanism to reduce risks to patients after liver transplant.

Breakthrough invasive fungal infection after liver transplantation in patients on targeted antifungal prophylaxis: A prospective multicentre study

Objective

To investigate the rate of and the risk factors for breakthrough‐IFI (b‐IFI) after orthotopic liver transplantation (OLT) according to the new definition proposed by Mycoses‐Study‐Group‐Education‐and‐Research‐Consortium (MSG‐ERC) and the European‐Confederation‐of‐Medical‐Mycology (ECMM).

Methods

Multicenter prospective study of adult patients who underwent OLT at three Italian hospitals, from January 2015 to December 2018. Targeted antifungal prophylaxis (TAP) protocol was developed and shared among participating centers. Follow‐up was 1‐year after OLT. B‐IFI was defined as infection occurring during exposure to antifungal prophylaxis. Risk factors for b‐IFI were analyzed among patients exposed to prophylaxis by univariable analysis.

Results

We enrolled 485 OLT patients. Overall compliance to TAP protocol was 64.3%, 220 patients received antifungal prophylaxis, 172 according to TAP protocol. Twenty‐nine patients were diagnosed of IFI within 1 year after OLT. Of them, 11 presented with b‐IFI within 17 (IQR 11‐33) and 16 (IQR 4‐30) days from OLT and from antifungal onset, respectively. Then out of 11 patients with b‐IFI were classified as having high risk of IFI and were receiving anti‐mould prophylaxis, nine with echinocandins and one with polyenes. Comparison of patients with and without b‐IFI showed significant differences for prior Candida colonization, need of renal replacement therapy after OLT, re‐operation, and CMV infection (whole blood CMV‐DNA >100 000 copies/mL). Although non‐significant, a higher rate of b‐IFI in patients on echinocandins was observed (8.2% vs 1.8%, P = .06).

Conclusions

We observed 5% of b‐IFI among OLT patients exposed to antifungal prophylaxis. The impact of echinocandins on b‐IFI risk in this setting should be further explored.

Strategies for the Prevention of Invasive Fungal Infections after Lung Transplant

Long-term survival after lung transplantation is lower than that associated with other transplanted organs. Infectious complications, most importantly invasive fungal infections, have detrimental effects and are a major cause of morbidity and mortality in this population. Candida infections predominate in the early post-transplant period, whereas invasive mold infections, usually those related to Aspergillus, are most common later on. This review summarizes the epidemiology and risk factors for invasive fungal diseases in lung transplant recipients, as well as the current evidence on preventive measures. These measures include universal prophylaxis, targeted prophylaxis, and preemptive treatment. Although there is consensus that a preventive strategy should be implemented, current data show no superiority of one preventive measure over another. Data are also lacking regarding the optimal antifungal regimen and the duration of treatment. As all current recommendations are based on observational, single-center, single-arm studies, it is necessary that this longstanding debate is settled with a multicenter randomized controlled trial.

Has the mortality from pulmonary mucormycosis changed over time? A systematic review and meta-analysis

OBJECTIVES

Pulmonary mucormycosis (PM) is increasingly being reported in immunocompromised patients and has a high mortality. Our aim was to assess the mortality of PM and its trend over time. We also evaluated the role of combined medical-surgical therapy in PM.

METHODS

We performed a systematic review of Pubmed, Embase, and Cochrane central databases. Studies were eligible if they described at least five confirmed cases of PM and reported mortality. We also assessed the effect of combined medical-surgical therapy versus medical treatment alone on PM mortality. We used a random-effects model to estimate the pooled mortality of PM and compared it across three time periods. The factors influencing mortality were assessed using meta-regression. We evaluated the risk difference (RD) of death in the following: subjects undergoing combined medical-surgical therapy versus medical therapy alone, subjects with isolated PM versus disseminated disease, and PM in diabetes mellitus (DM) versus non-DM as a risk factor.

RESULTS

We included 79 studies (1544 subjects). The pooled mortality of PM was 57.1% (95% confidence interval [CI] 51.7-62.6%). Mortality improved significantly over time (72.1% versus 58.3% versus 49.8% for studies before 2000, 2000-2009, and 2010-2020, respectively, p 0.00001). This improved survival was confirmed in meta-regression after adjusting for the study design, the country's income level, and the sample size. Combined medical-surgical therapy was associated with a significantly lower RD (95%CI) of death: -0.32 (-0.49 to -0.16). The disseminated disease had a higher risk of death than isolated PM, but DM was not associated with a higher risk of death than other risk factors.

CONCLUSIONS

While PM is still associated with high mortality, we noted improved survival over time. Combined medical-surgical therapy improved survival compared to medical treatment alone.

FDG PET/CT for Detection of Infectious Complications Following Solid Organ Transplantation

Infectious complications after solid organ transplantation (SOT) are often more severe and remain a diagnostic challenge due to vague and atypical clinical presentations. Diagnostic performance of conventional diagnostic tools is frequently inadequate which may lead to delayed diagnosis with the risk of poorer outcomes. This literature review aimed to investigate the current evidence on the use of ¹⁸F-fluoro-deoxy-glucose (FDG) Positron Emission Tomography (PET)/computer tomography (CT) in infectious complications after SOT. Based on search in PubMed, Medline, and Cochrane databases, 13 articles and 46 case reports were included. For inclusion, articles were to include data on patients with infectious complications after SOT, and where FDG PET/CT was part of the work-up. Final searches were conducted on 02 September 2020. Overall, in the absence of initial diagnostic clues, FDG PET/CT should be considered as the imaging technique of choice as it may guide further investigations and eventually reveal the diagnosis in most of the patients. However, the available literature of the role of FDG PET/CT in SOT recipients with infectious complications is scarce and well-designed prospective studies including control groups are warranted to establish the role of FDG PET/C/ in SOT recipients. The main drawback of FDG PET/CT is the lack of ability to differentiate between cancer and infectious diseases which are both highly prevalent in this patient group. Accordingly, the main reasons for "false" results of FDG PET/CT is the misdiagnosis of cancer in benign inflammatory or infectious processes, information which nonetheless can be useful.

Invasive fungal infection before and after liver transplantation

Invasive infections are a major complication before liver transplantation (LT) and in the early phase after surgery. There has been an increasing prevalence of invasive fungal disease (IFD), especially among the sickest patients with decompensated cirrhosis and acute-on-chronic liver failure, who suffer from a profound state of immune dysfunction and receive intensive care management. In such patients, who are listed for LT, development of an IFD often worsens hepatic and extra-hepatic organ dysfunction, requiring a careful evaluation before surgery. In the post-transplant setting, the burden of IFD has been reduced after the clinical advent of antifungal prophylaxis, even if several major issues still remain, such as duration, target population and drug type(s). Nevertheless, the development of IFD in the early phase after surgery significantly impairs graft and patient survival. This review outlines presentation, prophylactic and therapeutic strategies, and outcomes of IFD in LT candidates and recipients, providing specific considerations for clinical practice.

Infections in Lung Transplant Recipients during and after Prophylaxis

Background

The timeline of infections after lung transplantation has been changed with the introduction of new immunosuppressants and prophylaxis strategies. The study aimed to investigate the epidemiological characteristics of infectious diseases after lung transplantation in the current era.

Materials and Methods

All patients who underwent lung or heart–lung transplantation at our institution between October 29, 2008 and April 3, 2019 were enrolled. We retrospectively reviewed the patients' medical records till April 2, 2020.

Results

In total, 100 consecutive lung transplant recipients were enrolled. The median follow-up period was 28 months after lung transplantation. A total of 127 post–lung transplantation bacterial infections occurred. Catheter-related bloodstream infection (25/84, 29.8%) was the most common within 6 months and pneumonia (23/43, 53.5%) was the most common after 6 months. Most episodes (35/40, 87.5%) of respiratory viral infections occurred after 6 months, mainly as upper respiratory infections. The remaining episodes (5/40, 12.5%) mostly manifested as lower respiratory tract infections. Seventy cytomegalovirus infections observed in 43 patients were divided into 23 episodes occurring before and 47 episodes occurring after discontinuing prophylaxis. Of 10 episodes of cytomegalovirus disease, four occurred during prophylaxis and six occurred after prophylaxis. Of 23 episodes of post–lung transplantation fungal infection, 7 were aspergillosis and all occurred after the discontinuation of prophylaxis.

Conclusion

Lung transplant recipients experienced a high burden of infection even after 6 months, especially after the end of the prophylaxis period. Therefore, these patients should be continued to be monitored long-term for infectious disease.

Evaluation of targeted versus universal prophylaxis for the prevention of invasive fungal infections following lung transplantation

BACKGROUND

Antifungal prophylaxis to prevent invasive fungal infections (IFI) is widely used following lung transplantation, but the optimal strategy remains unclear. We compared universal with targeted antifungal prophylaxis for effectiveness in preventing IFI.

METHODS

Adult patients who underwent lung transplantation at the University of Michigan from /1 July 2014-31 December 2017 were studied for 18 months post-transplant. Universal prophylaxis consisted of itraconazole with or without inhaled liposomal amphotericin B. Using specific criteria, targeted prophylaxis was given with voriconazole for patients at risk for invasive pulmonary aspergillosis (IPA) and with fluconazole or micafungin for patients at risk for invasive candidiasis. Risk factors, occurrence of proven/probable IFI, and mortality were analyzed for the two prophylaxis cohorts.

RESULTS

Of 105 lung transplant recipients, 84 (80%) received a double lung transplant, and 38 (36%) of patients underwent transplant for pulmonary fibrosis. Fifty-nine (56%) patients received universal antifungal prophylaxis, and 46 (44%), targeted antifungal prophylaxis. Among 20 proven/probable IFI, there were 14 IPA, 4 invasive candidiasis, 1 cryptococcosis, and 1 deep sternal mold infection. Six (10%) IFI occurred in the universal prophylaxis cohort and 14 (30%) in the targeted prophylaxis cohort. Five of 6 (83%) IFI in the universal prophylaxis cohort, compared with 9/14 (64%) in the targeted prophylaxis cohort, were IPA Candida infections occurred only in the targeted prophylaxis cohort. The development of IFI was more likely in the targeted prophylaxis cohort than the universal prophylaxis cohort, HR = 4.32 (1.51-12.38), P = .0064.

CONCLUSIONS

Universal antifungal prophylaxis appears to be more effective than targeted antifungal prophylaxis for prevention of IFI after lung transplant.

Disseminated cryptococcosis with cutaneous manifestation

Cutaneous cryptococcosis is uncommon. It is usually a result of disseminated infection and can present with a wide variety of skin lesions. We report a case of disseminated cryptococcosis in a kidney transplant recipient who presented with nodular lesions in the forehead following a bout of acute cellular rejection.