Epidemiology, risk factors and outcomes of invasive aspergillosis in solid organ transplant recipients in the Swiss Transplant Cohort Study

Outcomes of Invasive Aspergillosis in Liver Transplant Recipients From an Institution Using Targeted Antifungal Prophylaxis and an Antifungal Stewardship Program

BACKGROUND

Recent evidence suggests liver transplant recipients (LiTRs) with invasive aspergillosis (IA) have lower rates of dissemination and mortality compared to historical data. However, contemporary data from other centers remain scarce. We aimed to evaluate modern IA outcomes at our institution, where targeted perioperative echinocandin prophylaxis and an active antifungal stewardship program (AFSP) have been implemented.

METHODS

This is a single-center retrospective analysis of patients who underwent liver transplantation between January 1, 2017 and June 30, 2022. During the study period, targeted anidulafungin perioperative prophylaxis was administered to patients considered high-risk for invasive fungal infection (IFI), and a multidisciplinary AFSP assisted with IFI diagnosis and management. Patients with proven and probable IA diagnosed post-operatively were identified using internationally accepted definitions. The primary outcomes were IA dissemination and 1-year all-cause mortality rates. Data were extracted from the electronic medical record and descriptive summary statistics were performed.

RESULTS

Six patients (6/377, 1.6%) met the inclusion criteria. Patients with IA were significantly more likely to be colonized with multidrug-resistant Gram-negative organisms compared to those without IA (50.0% vs. 12.1%, p = 0.006). The median time to IA diagnosis was 22 days post-transplant (IQR 5-109). No cases of dissemination were observed. One-year all-cause mortality was 16.7%.

CONCLUSION

Consistent with contemporary data, LiTRs had lower IA dissemination and mortality rates compared to earlier studies. These improved outcomes likely reflect a combination of modern advancements in liver transplantation, and we highlight two potentially modifiable interventions; targeted echinocandin prophylaxis and an AFSP. Further studies are needed to support their broader implementation.

Role of liposomal amphotericin B in intensive care unit: an expert opinion paper

INTRODUCTION

Invasive fungal infections (IFI) are frequent in patients admitted to the intensive care unit (ICU). The use of first-line antifungals like triazoles or echinocandins may be limited by the global spread of multi-drug resistance species, drug-drug interactions, low organ penetration, and some safety concerns in case of multi-organ failure. Liposomal amphotericin B (L-AmB) is a polyene drug with a broad activity against mold and yeast and an acceptable safety profile. To outline the role of L-AmB in the treatment of IFI in critically ill patients, a panel of experts was invited to draw up an expert opinion paper on the appropriate place in therapy of L-AmB in different clinical scenarios of patients admitted to ICU.

METHODS

A multidisciplinary group of 16 specialists in infectious disease, microbiology, pharmacology, and intensive care elaborated an expert opinion document through a multi-step approach: (1) the scientific panel defined the items and wrote the statements on the management of IFI in ICU, (2) a survey was submitted to an external panel to express agreement or disagreement on the statements, and (3) the panel reviewed the survey and implemented the final document.

RESULTS

The final document included 35 statements that focused on epidemiology and microbiological rationale of the use of systemic L-AmB in critically ill patients and its potential role in specific clinical scenarios in the ICU.

CONCLUSION

Systemic L-AmB may represent an appropriate therapeutic choice for IFI in ICU patients with different underlying conditions, especially when the use of first-line agents is undermined. This expert opinion paper may provide a useful guide for clinicians.

The Swiss Transplant Cohort Study: Implications for Transplant Infectious Diseases Research

The longitudinal, nationwide Swiss Transplant Cohort Study (STCS) follows > 92% of all transplant recipients with comprehensive data collection tailored to overall and organ-specific transplant outcomes. Transplant infectious disease events are assembled under the auspices of transplant ID specialists using common definitions. With over 6000 active patients and a median follow-up exceeding 6 years, the cohort offers a unique platform for understanding real-world epidemiology in transplanted patients. Beyond observational analysis, the STCS supports randomized controlled trials to address specific research questions. This overview highlights the achievements of the STCS and explores its future directions.

Invasive Aspergillosis in the Current Era

Despite significant advances, aspergillosis remains a critical health concern, with an evolving epidemiology and expanding populations of at-risk patients. Historically, fewer than 10 Aspergillus species were considered clinically significant. However, advancements in diagnostic technologies, such as DNA sequencing and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, have identified previously unrecognized "cryptic" Aspergillus species. This clinical review highlights the current epidemiology, risk factors, pathogenesis, clinical presentation, diagnosis, and invasive aspergillosis (IA) treatment. Diagnosing IA necessitates a multifaceted approach, integrating clinical evaluation, imaging studies, microbiological culture, serologic tests, and advanced molecular techniques.

Invasive aspergillosis caused by cryptic species in transplant recipients: A review

The clinical and microbiological characteristics of invasive aspergillosis (IA) caused by cryptic Aspergillus species have not been well-defined in transplant settings. However, IA is among the most common mould infections in solid organ and hematopoietic stem cell transplant recipients. Among 55 causative isolates in the 53 reported cases, Aspergillus calidoustus, A. lentulus, A. tubingensis, and A. udagawae were the four most common causative cryptic Aspergillus species. Newer diagnostic modalities, such as matrix-assisted laser desorption ionization-time of flight mass spectrometry, may help diagnose these cryptic species. Of the 24 cases with detailed clinical information, 13 had antifungal breakthrough infections. The 12-week mortality rates of all 24 cases, 7 cases of A. calidoustus, and 7 cases of A. lentulus were 46%, 43%, and 43%, respectively. Based on antifungal susceptibility profiles obtained from previous studies, an empiric antifungal regimen such as liposomal amphotericin B with or without echinocandin is recommended for A. calidoustus. A combination of an anti-mould azole and liposomal amphotericin B with or without an echinocandin is suggested for A. lentulus and A. udagawae. Additionally, any one of voriconazole, isavuconazole, or posaconazole with or without liposomal amphotericin B with or without an echinocandin is indicated for A. tubingensis. Newer antifungal agents may have more significant activity against Aspergillus cryptic species.

The epidemiological characteristics of invasive pulmonary aspergillosis and risk factors for treatment failure: a retrospective study

OBJECTIVE

The incidence of invasive pulmonary aspergillosis (IPA) is increasing gradually. This study analysed the epidemiological characteristics and prognostic factors of patients with IPA and explored the risk factors affecting prognosis.

MATERIALS AND METHODS

The clinical data and treatment of 92 patients with IPA were retrospectively analysed, and the patients were followed for 12 weeks. Patients were divided into an effective treatment group and an ineffective treatment group, and the risk factors affecting prognosis were discussed.

RESULTS

A total of 92 patients met the IPA inclusion criteria, and the most common genus of Aspergillus was Aspergillus fumigatus. The incidence of IPA was highest in patients with malignant tumours. IPA often coexisted with infections caused by other pathogens. We divided the patients into an effective treatment group and an ineffective treatment group according to prognosis. Compared with those in the effective treatment group, the procalcitonin (PCT) level, lactate dehydrogenase-to-albumin ratio (LDH/ALB) and neutrophil-to-lymphocyte ratio (NLR) in the ineffective treatment group were greater, the serum albumin level was lower, and the imaging findings revealed less nodules and bronchial wall thickening (P < 0.05). Among these factors, a decrease in the serum albumin concentration, an increase in the PCT level, coinfection and less bronchial wall thickening on imaging were independent risk factors for aspergillosis treatment failure.

CONCLUSION

A decreased albumin level, an elevated PCT level, coinfection, and less bronchial wall thickening were independent risk factors for treatment failure in patients with IPA. Attention should be given to the albumin level, coinfection status and imaging findings of patients.

Isavuconazole Versus Voriconazole as the First-line Therapy for Solid Organ Transplant Recipients With Invasive Aspergillosis: Comparative Analysis of 2 Multicenter Cohort Studies

BACKGROUND

Isavuconazole (ISA) and voriconazole (VORI) are recommended as the first-line treatment for invasive aspergillosis (IA). Despite theoretical advantages of ISA, both triazole agents have not been compared in solid organ transplant recipients.

METHODS

We performed a post hoc analysis of 2 retrospective multicenter cohorts of solid organ transplant recipients with invasive fungal disease (the SOTIS [Solid Organ Transplantation and ISavuconazole] and DiasperSOT [DIagnosis of ASPERgillosis in Solid Organ Transplantation] studies). We selected adult patients with proven/probable IA that were treated for ≥48 h with ISA (n = 57) or VORI (n = 77) as first-line therapy, either in monotherapy or combination regimen. The primary outcome was the rate of clinical response at 12 wk from the initiation of therapy. Secondary outcomes comprised 12-wk all-cause and IA-attributable mortality and the rates of treatment-emergent adverse events and premature treatment discontinuation.

RESULTS

Both groups were comparable in their demographics and major clinical and treatment-related variables. There were no differences in the rate of 12-wk clinical response between the ISA and VORI groups (59.6% versus 59.7%, respectively; odds ratio [OR], 0.99; 95% confidence interval [CI], 0.49-2.00). This result was confirmed after propensity score adjustment (OR, 0.81; 95% CI, 0.32-2.05) and matching (OR, 0.79; 95% CI, 0.31-2.04). All-cause and IA-attributable mortality were also similar. Patients in the ISA group were less likely to experience treatment-emergent adverse events (17.5% versus 37.7%; P = 0.011) and premature treatment discontinuation (8.8% versus 23.4%; P = 0.027).

CONCLUSIONS

Front-line treatment with ISA for posttransplant IA led to similar clinical outcomes than VORI, with better tolerability and higher treatment completion.

Invasive aspergillosis in liver transplant recipients in the current era

Invasive aspergillosis (IA) is a rare but fatal disease among liver transplant recipients (LiTRs). We performed a multicenter 1:2 case-control study comparing LiTRs diagnosed with proven/probable IA and controls with no invasive fungal infection. We included 62 IA cases and 124 matched controls. Disseminated infection occurred only in 8 cases (13%). Twelve-week all-cause mortality of IA was 37%. In multivariate analyses, systemic antibiotic usage (adjusted odds ratio [aOR], 4.74; P = .03) and history of pneumonia (aOR, 48.7; P = .01) were identified as independent risk factors associated with the occurrence of IA. Moreover, reoperation (aOR, 5.99; P = .01), systemic antibiotic usage (aOR, 5.03; P = .04), and antimold prophylaxis (aOR, 11.9; P = .02) were identified as independent risk factors associated with the occurrence of early IA. Among IA cases, Aspergillus colonization (adjusted hazard ratio [aHR], 86.9; P < .001), intensive care unit stay (aHR, 3.67; P = .02), disseminated IA (aHR, 8.98; P < .001), and dialysis (aHR, 2.93; P = .001) were identified as independent risk factors associated with 12-week all-cause mortality, while recent receipt of tacrolimus (aHR, 0.11; P = .001) was protective. Mortality among LiTRs with IA remains high in the current era. The identified risk factors and protective factors may be useful for establishing robust targeted antimold prophylactic and appropriate treatment strategies against IA.

Invasive fungal infections in patients with acute leukemia: A retrospective cohort study at a tertiary-care hospital

Invasive fungal infection (IFI) is an important cause of morbidity and mortality in acute leukemia patients. In the past few decades, the incidence of IFI has dramatically increased. Nevertheless, the management of IFI has become more complicated owing to changes in the epidemiology of fungal diseases and therapeutic regimens. Therefore, it is important to establish an appropriate strategy for centers that provide the diagnosis and treatment of acute leukemia patients based on scientific data and with available resources. In this study we investigated the incidence of IFI, pathogens, the use of diagnostic methods, and risk factors for IFI in acute leukemia patients over a 17-year period. A total of 502 acute leukemia patients (male/female: 57%/43%, mean age: 57.7 ± 15.5 years) hospitalized at adult and oncology hospitals between 2003 and 2020 were reviewed retrospectively. The incidence of proven and probable IFI was 13.2% (33.1%, when possible cases were included). The most common IFI was aspergillosis (49 patients, 9.7%), followed by candidemia, mucormycosis, and Pneumocystis jirovecii pneumonia. The galactomannan antigen test was positive in the serum of 39 (23.5%) patients and in bronchoalveolar lavage (BAL) fluid in 6 (3.6%) patients. Thirteen (7.8%) sputum cultures (11 Aspergillus spp. and 2 Candida spp.) and 4 (2.4%) BAL fluid (1 Aspergillus spp., 2 Candida spp., 1 P jirovecii) were positive for a fungal pathogen. Neutropenia, intensive care unit (ICU) follow-up and mechanical ventilation (MV) increased the risk of IFI by 3.5, 2.5, and 1.8 times, respectively. The median survival was 5 (range: 1.9-8) months. ICU follow-up shortened the survival by 12 months and increased the death risk by 2.49-fold. MV shortened survival by 57 months and increased the death risk by 3.82-fold. IFI remains a significant contributor to the morbidity and mortality in acute leukemia patients. Pulmonary involvement is the most common site. Neutropenia, ICU follow-up and MV are associated with an increased risk for IFI and mortality. We recommend in the IFI approach, to be aware of IFI in patients receiving intensive chemotherapy and/or recipients of hematopoietic stem cell transplantation, and to evaluate with microbiological, serological and radiological tests during the clinical follow-up.

Assessing the Impact of Posaconazole Cessation on Tacrolimus Serum Concentrations and Incident Cardiac Allograft Rejection: Take Caution

Invasive aspergillosis (IA) is a rare and often fatal complication of immunosuppression following orthotopic heart transplant. Prophylaxis plays a crucial role in preventing the emergence of this opportunistic infection. The azole class of medications are the bellwether agents utilized in this patient population. Unfortunately, given their impact on the Cytochrome P450 enzyme system, significant fluctuations in serum tacrolimus concentrations occur when initiating and stopping azole therapy, increasing the risk for prolonged periods of sub-optimal immunosuppression. While there are recommended dosing adjustments for these transition periods based on small data sets primarily with fluconazole, there is no published literature on recommended dosing adjustments for posaconazole. Given our institution utilizes posaconazole as the primary therapeutic for aspergillosis prophylaxis, we aimed to explore and report our local data to better guide dosing decisions during these transition periods.

The predictors of fungal infections after liver transplantation and the influence of fungal infections on outcomes

The primary objective of this study was to assess the incidence, timing, risk factors of fungal infections (FIs) within 3 months after liver transplantation (LT). The secondary objective was to evaluate the impact of FIs on outcomes. Four hundred and ten patients undergoing LT from January 2015 until January 2023 in a tertiary university hospital were included in the present retrospective cohort study to investigate the risk factors of FIs and to assess the impacts of FIs on the prognosis of LT recipients using logistic regression. The incidence of FIs was 12.4% (51/410), and median time from LT to the onset of FIs was 3 days. By univariate analysis, advanced recipient age, prolonged hospital stay prior to LT, high Model for End Stage Liver Disease (MELD) score, use of broad-spectrum antibiotics, and elevated white blood cell (WBC) count, increased operating time, massive blood loss and red blood cell transfusion, elevated alanine aminotransferase on day 1 and creatinine on day 3 after LT, prolonged duration of urethral catheter, prophylactic antifungal therapy, the need for mechanical ventilation and renal replacement therapy were identified as factors of increased post-LT FIs risk. Multivariate logistic regression analysis identified that recipient age ≥ 55 years[OR = 2.669, 95%CI: 1.292-5.513, P = 0.008], MELD score at LT ≥ 22[OR = 2.747, 95%CI: 1.274-5.922, P = 0.010], pre-LT WBC count ≥ 10 × 109/L[OR = 2.522, 95%CI: 1.117-5.692, P = 0.026], intraoperative blood loss ≥ 3000 ml [OR = 2.691, 95%CI: 1.262-5.738, P = 0.010], post-LT duration of urethral catheter > 4 d [OR = 3.202, 95%CI: 1.553-6.602, P = 0.002], and post-LT renal replacement therapy [OR = 5.768, 95%CI: 1.822-18.263, P = 0.003] were independently associated with the development of post-LT FIs. Post-LT prophylactic antifungal therapy ≥ 3 days was associated with a lower risk of the development of FIs [OR = 0.157, 95%CI: 0.073-0.340, P < 0.001]. As for clinical outcomes, FIs had a negative impact on intensive care unit (ICU) length of stay ≥ 7 days than those without FIs [OR = 3.027, 95% CI: 1.558-5.878, P = 0.001] but had no impact on hospital length of stay and 1-month all-cause mortality after LT. FIs are frequent complications after LT and the interval between the onset of FIs and LT was short. Risk factors for post-LT FIs included high MELD score at LT, advanced recipient age, pre-LT WBC count, massive intraoperative blood loss, prolonged post-LT duration of urethral catheter, and the need for post-LT renal replacement therapy. However, post-LT prophylactic antifungal therapy was independently associated with the reduction in the risk of FIs. FIs had a significant negative impact on ICU length of stay.

Food and Drug Administration Public Workshop Summary-Addressing Challenges in Inhaled Antifungal Drug Development

Allergic bronchopulmonary aspergillosis and invasive fungal diseases represent distinct infectious entities that cause significant morbidity and mortality. Currently, administered inhaled antifungal therapies are unapproved, have suboptimal efficacy, and are associated with considerable adverse reactions. The emergence of resistant pathogens is also a growing concern. Inhaled antifungal development programs are challenged by inadequate nonclinical infection models, highly heterogenous patient populations, low prevalence rates of fungal diseases, difficulties defining clinical trial enrollment criteria, and lack of robust clinical trial endpoints. On 25 September 2020, the US Food and Drug Administration (FDA) convened a workshop with experts in pulmonary medicine and infectious diseases from academia, industry, and other governmental agencies. Key discussion topics included regulatory incentives to facilitate development of inhaled antifungal drugs and combination inhalational devices, limitations of existing nonclinical models and clinical trial designs, patient perspectives, and industry insights.

The epidemiology of invasive fungal infections in transplant recipients

Transplant patients, including solid-organ transplant (SOT) and hematopoietic stem cell transplant (HSCT) recipients, are exposed to various types of complications, particularly rejection. To prevent these outcomes, transplant recipients commonly receive long-term immunosuppressive regimens that in turn make them more susceptible to a wide array of infectious diseases, notably those caused by opportunistic pathogens. Among these, invasive fungal infections (IFIs) remain a major cause of mortality and morbidity in both SOT and HSCT recipients. Despite the continuing improvement in early diagnostics and treatments of IFIs, the management of these infections in transplant patients is still complicated. Here, we provide an overview concerning the most recent trends in the epidemiology of IFIs in SOT and HSCT recipients by describing the prominent yeast and mold species involved, the timing of post-transplant IFIs and the risk factors associated with their occurrence in these particularly weak populations. We also give special emphasis into basic research advances in the field that recently suggested a role of the global and long-term prophylactic regimen in orchestrating various biological disturbances in the organism and conditioning the emergence of the most adapted fungal strains to the particular physiological profiles of transplant patients.

Risk Factors for Early Fungal Disease in Solid Organ Transplant Recipients: A Systematic Review and Meta-analysis

BACKGROUND

Invasive fungal infections are associated with high morbidity in solid organ transplant recipients. Risk factor modification may help with preventative efforts. The objective of this study was to identify risk factors for the development of fungal infections within the first year following solid organ transplant.

METHODS

We searched for eligible articles through February 3, 2023. Studies published after January 1, 2001, that pertained to risk factors for development of invasive fungal infections in solid organ transplant were reviewed for inclusion. Of 3087 articles screened, 58 were included. Meta-analysis was conducted using a random-effects model to evaluate individual risk factors for the primary outcome of any invasive fungal infections and invasive candidiasis or invasive aspergillosis (when possible) within 1 y posttransplant.

RESULTS

We found 3 variables with a high certainty of evidence and strong associations (relative effect estimate ≥ 2) to any early invasive fungal infections across all solid organ transplant groups: reoperation (odds ratio [OR], 2.92; confidence interval [CI], 1.79-4.75), posttransplant renal replacement therapy (OR, 2.91; CI, 1.87-4.51), and cytomegalovirus disease (OR, 2.97; CI, 1.78-4.94). Both posttransplant renal replacement therapy (OR, 3.36; CI, 1.78-6.34) and posttransplant cytomegalovirus disease (OR, 2.81; CI, 1.47-5.36) increased the odds of early posttransplant invasive aspergillosis. No individual variables could be pooled across groups for invasive candidiasis.

CONCLUSIONS

Several common risk factors exist for the development of any invasive fungal infections in solid organ transplant recipients. Additional risk factors for invasive candidiasis and aspergillosis may be unique to the pathogen, transplanted organ, or both.

Pharmacological management of invasive mold infections in solid organ transplant recipients

INTRODUCTION

Solid organ transplant (SOT) recipients face an increased susceptibility to invasive fungal infection (IFI) due to filamentous fungi. Post-transplant invasive aspergillosis (IA) and mucormycosis are related to exceedingly high mortality rates and graft loss risk, and its management involve a unique range of clinical challenges.

AREAS COVERED

First, the current treatment recommendations for IA and mucormycosis among SOT recipients are critically reviewed, including the supporting evidence. Next, we discussed particular concerns in this patient population, such as drug-drug interactions (DDIs) between triazoles and post-transplant immunosuppression or treatment-related toxicity. The role for immunomodulatory and host-targeted therapies is also considered, as well as the theoretical impact of the intrinsic antifungal activity of calcineurin inhibitors. Finally, a personal opinion is made on future directions in the pharmacological approach to post-transplant IFI.

EXPERT OPINION

Despite relevant advances in the treatment of mold IFIs in the SOT setting, such as the incorporation of isavuconazole (with lower incidence of DDIs and better tolerability than voriconazole), there remains a large room for improvement in areas such as the position of combination therapy or the optimal strategy for the reduction of baseline immunosuppression. Importantly, future studies should define the specific contribution of newer antifungal agents and classes.

Invasive pulmonary aspergillosis following human metapneumovirus infection in solid-organ transplant recipients: Another virus to add to the list

There is increasing recognition that respiratory viral infections such as influenza, respiratory syncytial virus, parainfluenza virus, adenovirus, and SARS-CoV-2 can promote the development of invasive fungal pulmonary coinfections, particularly invasive aspergillosis, both in immunocompetent and immunocompromised patients. To date, there are no case reports exploring the role of human metapneumovirus as a risk factor for fungal coinfection. Below, we describe the case of a 63-year-old woman who received a kidney transplant and developed invasive pulmonary aspergillosis after a human metapneumovirus infection and discuss the possible phenomena that could favor this association.

Identifying CNS infections in transplantation and immunomodulatory therapy

Opportunistic central nervous system (CNS) infections are a significant cause of morbidity and mortality in immunocompromized patients, including those undergoing transplantation and receiving immunomodulatory therapy. Particularly in these individuals, the clinical presentation of these infections may have atypical patterns, emphasizing the need to consider various diagnostic possibilities, including noninfectious conditions. Quick and accurate identification, along with prompt treatment, is crucial for improving patient outcomes. Therefore, understanding which pathogens are likely to cause infection based on factors such as timing post-transplantation, specific organ transplant, and the mechanism of action of immunomodulatory medications is essential. This review will provide a detailed description of the types of infections that may arise in the context of transplantation and immunomodulatory therapy.

Isavuconazole for Treating Invasive Mould Disease in Solid Organ Transplant Recipients

Solid organ transplant (SOT) recipients have a higher risk of developing invasive mould diseases (IMD). Isavuconazole is a novel broad-spectrum azole active against Aspergillus spp. and Mucor, well tolerated, with an excellent bioavailability and predictable pharmacokinetics, that penetrates in most tissues rapidly, and has few serious adverse effects, including hepatic toxicity. Contrary to other broad-spectrum azoles, such as voriconazole and posaconazole, isavuconazole appears to show significant smaller drug-drug interactions with anticalcineurin drugs. We have performed an extensive literature review of the experience with the use of isavuconazole in SOT, which included the SOTIS and the ISASOT studies, and published case reports. More than 140 SOT recipients treated with isavuconazole for IMD were included. Most patients were lung and kidney recipients treated for an Aspergillus infection. Isavuconazole was well tolerated (less than 10% of patients required treatment discontinuation). The clinical responses appeared comparable to that found in other high-risk patient populations. Drug-drug interactions with immunosuppressive agents were manageable after the reduction of tacrolimus and the adjustment of mTOR inhibitors at the beginning of treatment. In conclusion, isavuconazole appears to be a reasonable option for the treatment of IMD in SOT. More clinical studies are warranted.

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.

Invasive Aspergillosis among Lung Transplant Recipients during Time Periods with Universal and Targeted Antifungal Prophylaxis-A Nationwide Cohort Study

The optimal prevention strategy for invasive aspergillosis (IA) in lung transplant recipients (LTXr) is unknown. In 2016, the Danish guidelines were changed from universal to targeted IA prophylaxis. Previously, we found higher rates of adverse events in the universal prophylaxis period. In a Danish nationwide study including LTXr, for 2010-2019, we compared IA rates in time periods with universal vs. targeted prophylaxis and during person-time with vs. person-time without antifungal prophylaxis. IA hazard rates were analyzed in multivariable Cox models with adjustment for time after LTX. Among 295 LTXr, antifungal prophylaxis was initiated in 183/193 and 6/102 during the universal and targeted period, respectively. During the universal period, 62% discontinued prophylaxis prematurely. The median time on prophylaxis was 37 days (IQR 11-84). IA was diagnosed in 27/193 (14%) vs. 15/102 (15%) LTXr in the universal vs. targeted period, with an adjusted hazard ratio (aHR) of 0.94 (95% CI 0.49-1.82). The aHR of IA during person-time with vs. person-time without antifungal prophylaxis was 0.36 (95% CI 0.12-1.02). No difference in IA was found during periods with universal vs. targeted prophylaxis. Prophylaxis was protective of IA when taken. Targeted prophylaxis may be preferred over universal due to comparable IA rates and lower rates of adverse events.

Associations between invasive aspergillosis and cytomegalovirus in lung transplant recipients: a nationwide cohort study

Cytomegalovirus (CMV) and invasive aspergillosis (IA) cause morbidity among lung transplant recipients (LTXr). Early diagnosis and treatment could improve outcomes. We examined rates of CMV after IA and vice versa to assess whether screening for one infection is warranted after detecting the other. All Danish LTXr, 2010-2019, were followed for IA and CMV for 2 years after transplantation. IA was defined using ISHLT criteria. Adjusted incidence rate ratios (aIRR) were estimated by Poisson regression adjusted for time after transplantation. We included 295 LTXr, among whom CMV and IA were diagnosed in 128 (43%) and 48 (16%). The risk of CMV was high the first 3 months after IA, IR 98/100 person-years of follow-up (95% CI 47-206). The risk of IA was significantly increased in the first 3 months after CMV, aIRR 2.91 (95% CI 1.32-6.44). Numbers needed to screen to diagnose one case of CMV after IA, and one case of IA after CMV was approximately seven and eight, respectively. Systematic screening for CMV following diagnosis of IA, and vice versa, may improve timeliness of diagnosis and outcomes for LTXr.

Invasive aspergillosis in adult patients in Australia and New Zealand: 2017-2020

Background

New and emerging risks for invasive aspergillosis (IA) bring the need for contemporary analyses of the epidemiology and outcomes of IA, in order to improve clinical practice.

Methods

The study was a retrospective, multicenter, cohort design of proven and probable IA in adults from 10 Australasian tertiary centres (January 2017-December 2020). Descriptive analyses were used to report patients' demographics, predisposing factors, mycological characteristics, diagnosis and management. Accelerated failure-time model was employed to determine factor(s) associated with 90-day all-cause mortality (ACM).

Findings

Of 382 IA episodes, 221 (in 221 patients) fulfilled inclusion criteria - 53 proven and 168 probable IA. Median patient age was 61 years (IQR 51-69). Patients with haematologic malignancies (HM) comprised 49.8% of cases. Fifteen patients (6.8%) had no pre-specified immunosuppression and eleven patients (5.0%) had no documented comorbidity. Only 30% of patients had neutropenia. Of 170 isolates identified, 40 (23.5%) were identified as non-Aspergillus fumigatus species complex. Azole-resistance was present in 3/46 (6.5%) of A. fumigatus sensu stricto isolates. Ninety-day ACM was 30.3%. HM (HR 1.90; 95% CI 1.04-3.46, p = 0.036) and ICU admission (HR 4.89; 95% CI 2.93-8.17, p < 0.001) but not neutropenia (HR 1.45; 95% CI 0.88-2.39, p = 0.135) were associated with mortality. Chronic kidney disease was also a significant predictor of death in the HM subgroup (HR 3.94; 95% CI 1.15-13.44, p = 0.028).

Interpretation

IA is identified in high number of patients with mild/no immunosuppression in our study. The relatively high proportion of non-A. fumigatus species complex isolates and 6.5% azole-resistance rate amongst A. fumigatus sensu stricto necessitates accurate species identification and susceptibility testing for optimal patient outcomes.

Funding

This work is unfunded. All authors' financial disclosures are listed in detail at the end of the manuscript.

Atypical imaging patterns during lung invasive mould diseases: lessons for clinicians

Imaging of pulmonary invasive mould diseases (IMDs), which represents a cornerstone in their work-up, is mainly based on computed tomography (CT). The purpose of this review is to discuss their CT features, mainly those related to aspergillosis and mucormycosis. We will especially focus on atypical radiological presentations that are increasingly observed among non-neutropenic emerging populations of patients at risk, such as those receiving novel anticancer therapies or those in the intensive care unit. We will also discuss the interest of other available imaging techniques, mainly positron emission tomography/CT, that may play a role in the diagnosis as well as evaluation of disease extent and follow-up. We will show that any new airway-centred abnormality or caveated lesion should evoke IMDs in mildly immunocompromised hosts. Limitations in their recognition may be due to potential underlying abnormalities that increase the complexity of interpretation of lung imaging, as well as the non-specificity of imaging features. In this way, the differentials of all morphological/metabolic aspects must be kept in mind for the optimal management of patients, as well as the benefit of evaluation of the vascular status.

Invasive aspergillosis in liver transplant recipients, an infectious complication with low incidence but significant mortality

BACKGROUND

Infections, including invasive fungal infections (IFIs), are among the leading causes of mortality in liver transplant recipients during the first year post-transplantation.

AIM

To investigate the epidemiology, clinical manifestations, risk factors, treatment outcomes, and mortality rate of post-liver transplantation invasive aspergillosis (IA).

METHODS

In this case-control study, 22 patients with IA were identified by reviewing the archived and electronic medical records of 850 patients who received liver transplants at the Imam Khomeini Hospital complex in Tehran, Iran, between 2014 and 2019. The control group comprised 38 patients without IA infection matched for age and sex. The information obtained included the baseline characteristics of liver transplant patients, operative reports, post-transplantation characteristics of both groups and information about the fungal infection of the patient group.

RESULTS

The prevalence rate of IA among liver transplant recipients at Imam Khomeini Hospital was 2.7%. The risk factors of IA among studied patients included high serum creatinine levels before and post-transplant, renal replacement therapy, antithymocyte globulin induction therapy, post-transplant bile leakage, post-transplant hepatic artery thrombosis, repeated surgery within 30 d after the transplant, bacterial pneumonia before the aspergillosis diagnosis, receiving systemic antibiotics before the aspergillus infection, cytomegalovirus infection, and duration of post-transplant hospitalization in the intensive care unit. The most prevalent form of infection was invasive pulmonary aspergillosis, and the most common chest computed tomography scan findings were nodules, pleural effusion, and the halo sign. In the case group, prophylactic antifungal therapy was administered more frequently than in the control group. The antifungal therapy response rate at 12 wk was 63.7%. The 3- and 12- mo mortality rates of the patients with IA were 36.4% and 45.4%, respectively (compared with the mortality rate of the control group in 12 mo, which was zero).

CONCLUSION

In this study, the prevalence of IA among liver transplant recipients was relatively low. However, it was one of the leading causes of mortality following liver transplantation. Targeted antifungal therapy may be a factor in the low incidence of infections at our facility. Identifying the risk factors of IFIs, maintaining an elevated level of clinical suspicion, and initiating early antifungal treatment may significantly improve the prognosis and reduce the mortality rate of liver transplant recipients.

Invasive fungal infections in liver diseases

Patients with liver diseases, including decompensated cirrhosis, alcohol-associated hepatitis, and liver transplant recipients are at increased risk of acquiring invasive fungal infections (IFIs). These infections carry high morbidity and mortality. Multiple factors, including host immune dysfunction, barrier failures, malnutrition, and microbiome alterations, increase the risk of developing IFI. Candida remains the most common fungal pathogen causing IFI. However, other pathogens, including Aspergillus, Cryptococcus, Pneumocystis, and endemic mycoses, are being increasingly recognized. The diagnosis of IFIs can be ascertained by the direct observation or isolation of the pathogen (culture, histopathology, and cytopathology) or by detecting antigens, antibodies, or nucleic acid. Here, we provide an update on the epidemiology, pathogenesis, diagnosis, and management of IFI in patients with liver disease and liver transplantation.

Antifungal prophylaxis and pre-emptive therapy: When and how?

The growing pool of critically ill or immunocompromised patients leads to a constant increase of life-threatening invasive infections by fungi such as Aspergillus spp., Candida spp. and Pneumocystis jirovecii. In response to this, prophylactic and pre-emptive antifungal treatment strategies have been developed and implemented for high-risk patient populations. The benefit by risk reduction needs to be carefully weighed against potential harm caused by prolonged exposure against antifungal agents. This includes adverse effects and development of resistance as well as costs for the healthcare system. In this review, we summarise evidence and discuss advantages and downsides of antifungal prophylaxis and pre-emptive treatment in the setting of malignancies such as acute leukaemia, haematopoietic stem cell transplantation, CAR-T cell therapy, and solid organ transplant. We also address preventive strategies in patients after abdominal surgery and with viral pneumonia as well as individuals with inherited immunodeficiencies. Notable progress has been made in haematology research, where strong recommendations regarding antifungal prophylaxis and pre-emptive treatment are backed by data from randomized controlled trials, whereas other critical areas still lack high-quality evidence. In these areas, paucity of definitive data translates into centre-specific strategies that are based on interpretation of available data, local expertise, and epidemiology. The development of novel immunomodulating anticancer drugs, high-end intensive care treatment and the development of new antifungals with new modes of action, adverse effects and routes of administration will have implications on future prophylactic and pre-emptive approaches.

Early-Onset Invasive Pulmonary Aspergillosis in a Liver Transplant Patient: A Case Report

Invasive pulmonary aspergillosis (IPA) in liver transplant patients remains rare but exceedingly fatal. The diagnostic challenges associated with this condition are compounded by its infrequent onset within the first two weeks following transplantation. Moreover, therapeutic management is complex due to the intricate drug interactions between triazole antifungals and calcineurin inhibitor immunosuppressants. We present the case of a 63-year-old male who underwent uncomplicated liver transplantation (LT) and developed early-onset IPA. Despite maximal efforts, the patient expired. This report aims to underscore the vital importance of timely diagnosis and therapy in preventing the insidious progression of invasive disease and subsequent mortality.

Diagnosis and Treatment of Fungal Infections in Lung Transplant Recipients

Fungal infections are a significant source of morbidity in the lung transplant population via direct allograft damage and predisposing patients to the development of chronic lung allograft dysfunction. Prompt diagnosis and treatment are imperative to limit allograft damage. This review article discusses incidence, risk factors, and symptoms with a specific focus on diagnostic and treatment strategies in the lung transplant population for fungal infections caused by Aspergillus, Candida, Coccidioides, Histoplasma, Blastomyces, Scedosporium/Lomentospora, Fusarium, and Pneumocystis jirovecii. Evidence for the use of newer triazole and inhaled antifungals to treat isolated pulmonary fungal infections in lung transplant recipients is also discussed.

Invasive Aspergillosis and the Impact of Azole-resistance

Purpose of Review

IA (invasive aspergillosis) caused by azole-resistant strains has been associated with higher clinical burden and mortality rates. We review the current epidemiology, diagnostic, and therapeutic strategies of this clinical entity, with a special focus on patients with hematologic malignancies.

Recent Findings

There is an increase of azole resistance in Aspergillus spp. worldwide, probably due to environmental pressure and the increase of long-term azole prophylaxis and treatment in immunocompromised patients (e.g., in hematopoietic stem cell transplant recipients). The therapeutic approaches are challenging, due to multidrug-resistant strains, drug interactions, side effects, and patient-related conditions.

Summary

Rapid recognition of resistant Aspergillus spp. strains is fundamental to initiate an appropriate antifungal regimen, above all for allogeneic hematopoietic cell transplantation recipients. Clearly, more studies are needed in order to better understand the resistance mechanisms and optimize the diagnostic methods to identify Aspergillus spp. resistance to the existing antifungal agents/classes. More data on the susceptibility profile of Aspergillus spp. against the new classes of antifungal agents may allow for better treatment options and improved clinical outcomes in the coming years. In the meantime, continuous surveillance studies to monitor the prevalence of environmental and patient prevalence of azole resistance among Aspergillus spp. is absolutely crucial.

Invasive aspergillosis in liver transplant recipients

BACKGROUND

Liver transplantation is increasing worldwide with underlying pathologies dominated by metabolic and alcoholic diseases in developed countries.

METHODS

We provide a narrative review of invasive aspergillosis (IA) in liver transplant (LT) recipients. We searched PubMed and Google Scholar for references without language and time restrictions.

RESULTS

The incidence of IA in LT recipients is low (1.8%), while mortality is high (∼50%). It occurs mainly early (<3 months) after LT. Some risk factors have been identified before (corticosteroid, renal, and liver failure), during (massive transfusion and duration of surgical procedure), and after transplantation (intensive care unit stay, re-transplantation, re-operation). Diagnosis can be difficult and therefore requires full radiological and clinicobiological collaboration. Accurate identification of Aspergillus species is recommended due to the cryptic species, and susceptibility testing is crucial given the increasing resistance of Aspergillus fumigatus to azoles. It is recommended to reduce the dose of tacrolimus (50%) and to closely monitor the trough level when introducing voriconazole, isavuconazole, and posaconazole. Surgery should be discussed on a case-by-case basis. Antifungal prophylaxis is recommended in high-risk patients. Environmental preventative measures should be implemented to prevent outbreaks of nosocomial aspergillosis in LT recipient units.

CONCLUSION

IA remains a very serious disease in LT patients and should be promptly sought and, if possible, prevented by clinicians when risk factors are identified.

Isavuconazole for the Treatment of Invasive Mold Disease in Solid Organ Transplant Recipients: A Multicenter Study on Efficacy and Safety in Real-life Clinical Practice

BACKGROUND

Isavuconazole has theoretical advantages over other mold-active triazoles for the treatment of invasive aspergillosis and mucormycosis after solid organ transplantation (SOT). The available clinical experience, nevertheless, is scarce.

METHODS

We performed a retrospective study including all adult SOT recipients with proven or probable invasive mold disease (IMD) that received isavuconazole for ≥24 h as first-line or salvage therapy at 10 Spanish centers between September 2017 and November 2021. The primary efficacy outcome was clinical response (complete or partial resolution of attributable symptoms and findings) by weeks 6 and 12. Safety outcomes included the rates of treatment-emergent adverse events and premature isavuconazole discontinuation.

RESULTS

We included 81 SOT recipients that received isavuconazole for a median of 58.0 days because of invasive aspergillosis (n = 71) or mucormycosis (n = 10). Isavuconazole was used as first-line (72.8%) or salvage therapy due because of previous treatment-emergent toxicity (11.1%) or refractory IMD (7.4%). Combination therapy was common (37.0%), mainly with an echinocandin or liposomal amphotericin B. Clinical response by weeks 6 and 12 was achieved in 53.1% and 54.3% of patients, respectively, and was more likely when isavuconazole was administered as first-line single-agent therapy. At least 1 treatment-emergent adverse event occurred in 17.3% of patients, and 6.2% required premature discontinuation. Daily tacrolimus dose was reduced in two-thirds of patients by a median of 50.0%, although tacrolimus levels remained stable throughout the first month of therapy.

CONCLUSIONS

Isavuconazole is a safe therapeutic option for IMD in SOT recipients, with efficacy comparable to other patient groups.

Pulmonary aspergillosis: diagnosis and treatment

Aspergillusspecies are the most frequent cause of fungal infections of the lungs with a broad spectrum of clinical presentations including invasive pulmonary aspergillosis (IPA) and chronic pulmonary aspergillosis (CPA). IPA affects immunocompromised populations, which are increasing in number and diversity with the advent of novel anti-cancer therapies. Moreover, IPA has emerged as a complication of severe influenza and coronavirus disease 2019 in apparently immunocompetent hosts. CPA mainly affects patients with pre-existing lung lesions and is recognised increasingly frequently among patients with long-term survival following cure of tuberculosis or lung cancer. The diagnosis of pulmonary aspergillosis is complex as it relies on the presence of clinical, radiological and microbiological criteria, which differ according to the type of pulmonary aspergillosis (IPA or CPA) and the type of patient population. The management of pulmonary aspergillosis is complicated by the limited number of treatment options, drug interactions, adverse events and the emergence of antifungal resistance.

Therapeutic Approaches for Combating Aspergillus Associated Infection

Now-a-days fungal infection emerges as a significant problem to healthcare management systems due to high frequency of associated morbidity, mortality toxicity, drug-drug interactions, and resistance of the antifungal agents. Aspergillus is the most common mold that cause infection in immunocompromised hosts. It's a hyaline mold that is cosmopolitan and ubiquitous in nature. Aspergillus infects around 10 million population each year with a mortality rate of 30-90%. Clinically available antifungal formulations are restricted to four classes (i.e., polyene, triazole, echinocandin, and allylamine), and each of them have their own limitations associated with the activity spectrum, the emergence of resistance, and toxicity. Consequently, novel antifungal agents with modified and altered chemical structures are required to combat these invasive fungal infections. To overcome these limitations, there is an urgent need for new antifungal agents that can act as potent drugs in near future. Currently, some compounds have shown effective antifungal activity. In this review article, we have discussed all potential antifungal therapies that contain old antifungal drugs, combination therapies, and recent novel antifungal formulations, with a focus on the Aspergillus associated infections.

Genomic and Molecular Identification of Genes Contributing to the Caspofungin Paradoxical Effect in Aspergillus fumigatus

Aspergillus fumigatus is a deadly opportunistic fungal pathogen responsible for ~100,000 annual deaths. Azoles are the first line antifungal agent used against A. fumigatus, but azole resistance has rapidly evolved making treatment challenging. Caspofungin is an important second-line therapy against invasive pulmonary aspergillosis, a severe A. fumigatus infection. Caspofungin functions by inhibiting β-1,3-glucan synthesis, a primary and essential component of the fungal cell wall. A phenomenon termed the caspofungin paradoxical effect (CPE) has been observed in several fungal species where at higher concentrations of caspofungin, chitin replaces β-1,3-glucan, morphology returns to normal, and growth rate increases. CPE appears to occur in vivo, and it is therefore clinically important to better understand the genetic contributors to CPE. We applied genomewide association (GWA) analysis and molecular genetics to identify and validate candidate genes involved in CPE. We quantified CPE across 67 clinical isolates and conducted three independent GWA analyses to identify genetic variants associated with CPE. We identified 48 single nucleotide polymorphisms (SNPs) associated with CPE. We used a CRISPR/Cas9 approach to generate gene deletion mutants for seven genes harboring candidate SNPs. Two null mutants, ΔAfu3g13230 and ΔAfu4g07080 (dscP), resulted in reduced basal growth rate and a loss of CPE. We further characterized the dscP phosphatase-null mutant and observed a significant reduction in conidia production and extremely high sensitivity to caspofungin at both low and high concentrations. Collectively, our work reveals the contribution of Afu3g13230 and dscP in CPE and sheds new light on the complex genetic interactions governing this phenotype. IMPORTANCE This is one of the first studies to apply genomewide association (GWA) analysis to identify genes involved in an Aspergillus fumigatus phenotype. A. fumigatus is an opportunistic fungal pathogen that causes hundreds of thousands of infections and ~100,000 deaths each year, and antifungal resistance has rapidly evolved in this species. A phenomenon called the caspofungin paradoxical effect (CPE) occurs in some isolates, where high concentrations of the drug lead to increased growth rate. There is clinical relevance in understanding the genetic basis of this phenotype, since caspofungin concentrations could lead to unintended adverse clinical outcomes in certain cases. Using GWA analysis, we identified several interesting candidate polymorphisms and genes and then generated gene deletion mutants to determine whether these genes were important for CPE. Two of these mutant strains (ΔAfu3g13230 and ΔAfu4g07080/ΔdscP) displayed a loss of the CPE. This study sheds light on the genes involved in clinically important phenotype CPE.

Antimicrobial stewardship programs in solid-organ transplant recipients in Switzerland

INTRODUCTION

Antimicrobial stewardship programs (ASPs) are essential for minimizing the emergence of antimicrobial resistance, while improving patient outcomes. The current status of ASP in the field of organ transplantation in Switzerland has not been well characterized.

METHODS

We describe in this article the current status of ASP and discuss challenges and opportunities of implementing ASP dedicated to solid-organ transplant (SOT) recipients in Switzerland.

RESULTS

ASP have been implemented in the Swiss healthcare system over the last years, although specific strategies for SOT recipients are mostly based on transplant infectious diseases (TID) consultations rather than structured institutional interventions. Even so, there is a unique opportunity for developing a successful ASP in Switzerland that also specifically addresses areas of practice relevant to SOT recipients. This is due to the existent network of TID specialists in close collaboration with transplant physicians, the small number of centers involved in the care of transplant recipients, and the development of the Swiss Transplant Cohort Study (STCS), a prospective nationwide cohort of SOT recipients in Switzerland. The STCS can identify actual challenges through the updated reports on the epidemiology on transplant infections, accurately monitor the impact of potential antimicrobial stewardship interventions, and represent an opportunity for nesting of pragmatic randomized controlled trials to address key questions about optimized antibiotic use for SOT recipients.

CONCLUSIONS

Although ASP in SOT recipients rely more on specific TID consultations than in general antimicrobial stewardship teams, we identified several opportunities for the implementation of a successful ASP in Switzerland.

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 randomised controlled trials. A network meta-analysis was performed for invasive fungal infection (IFI) among different agents in 14 randomised 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.

Antifungal prophylactic effectiveness and intrapulmonary concentrations of voriconazole versus posaconazole in lung transplant recipients

Invasive fungal diseases (IFDs) are one of the leading causes of death in lung transplant recipients. This study aimed to compare the antifungal prophylactic effectiveness, intrapulmonary and plasma levels of voriconazole with posaconazole in lung transplant recipients. This retrospective cohort study analyzed adult recipients who underwent lung transplantation between June 2017 and December 2020. Voriconazole oral tablets or posaconazole oral suspension were used for prophylaxis against posttransplant IFD. Drug concentrations in bronchoalveolar lavage fluid (BALF) and plasma were measured by using liquid chromatography-mass spectrometry. The 182 recipients included 142 in the voriconazole group and 40 in the posaconazole group. The trough plasma levels were comparable between voriconazole and posaconazole (1.65 ± 0.09 vs. 1.69 ± 0.03 μg/ml, p = 0.55). However, the BALF levels were significantly higher for posaconazole than voriconazole (17.47 ± 11.51 vs. 0.56 ± 0.49 μg/ml, p < 0.001). There was no significant difference in the total incidence of breakthrough IFDs between the voriconazole and posaconazole groups (10.6% vs. 7.5%, p = 0.77). The intrapulmonary concentrations of posaconazole were significantly higher than voriconazole. The two agents had comparable antifungal prophylactic effectiveness.

Primary spinal infections in patients with solid organ transplant: a systematic literature review and illustrative case

BACKGROUND

Primary spinal infections (PSIs) are a group of uncommon but serious infectious diseases considered more prevalent and aggressive among patients with chronic immunocompromised states. Association of PSI and solid organ transplant has not been systematically analyzed. The authors performed a systematic review analyzing clinical presentation and mortality of patients with PSI in the setting of solid organ transplant.

OBSERVATIONS

PSIs in patients with immunosuppressive therapy, such as those with solid organ transplant, may behave differently in terms of epidemiology, clinical presentation, and outcomes compared with nonimmunosuppressed patients. Overall PSI in solid organ transplant patients is associated with a high rate of neurological compromise, postoperative complications, and mortality.

LESSONS

Accurate diagnosis and appropriate treatment of PSI require a multidisciplinary effort. Localized pain is the most frequently reported symptom associated with PSI. As opposed to PSI in patients without transplant, inflammatory and infectious markers such as white blood cells and C-reactive protein are often not elevated. Furthermore, the causative microorganism profile varies significantly when compared to pyogenic spinal infection in patients without transplant. Aspergillus species was responsible for spondylodiscitis in transplant patients in more than 50% of cases, and the incidence of Aspergillus infection is projected to rise in the coming years.

How Has the Aspergillosis Case Fatality Rate Changed over the Last Two Decades in Spain?

(1) Background: Aspergillus produces high morbidity and mortality, especially in at-risk populations. In Spain, the evolution of mortality in recent years due to this fungus is not well established. The aim of this study was to estimate the case fatality rate of aspergillosis in inpatients from 1997 to 2017 in Spain. (2) Methodology: A retrospective descriptive study was conducted with records of inpatients admitted to the National Health System with a diagnosis of aspergillosis. (3) Principal findings: Of 32,960 aspergillosis inpatients, 24.5% of deaths were registered, and 71% of the patients who died were men. The percentage of deaths increased progressively with age. The case fatality rate progressively decreased over the period, from 25.4 and 27.8% in 1997–1998 to values of 20.6 and 20.8% in 2016 and 2017. Influenza and pneumonia occurrence/association significantly increased case fatality rates in all cases. (4) Conclusions: Our study shows that lethality significantly decreased in the last two decades despite the increase in cases. This highlights the fact that patients with solid and/or hematological cancer do not have a much higher mortality rate than the group of patients with pneumonia or influenza alone, these two factors being the ones that cause the highest CFRs. We also need studies that analyze the causes of mortality to decrease it and studies that evaluate the impact of COVID-19.

Central Nervous System Infections in Solid Organ Transplant Recipients: Results from the Swiss Transplant Cohort Study

OBJECTIVES

To describe the epidemiology and clinical presentation of central nervous system (CNS) infections in solid organ transplant (SOT) recipients in the current era of transplantation.

METHODS

Patients from the Swiss Transplant Cohort Study (STCS) transplanted between 2008 and 2018 were included with a median follow-up of 3.8 years. Epidemiological, microbiological, and clinical data were extracted from the STCS database and patients' medical records. We calculated incidence rates and 90-day survival of transplant recipients with CNS infection.

RESULTS

Among 4762 patients, 42 episodes of CNS infection in 41 (0.8%) SOT recipients were identified, with an overall incidence rate of 2.06 per 1000 patient-years. Incidence of CNS infections was similar across all types of transplantations. Time to CNS infection onset ranged from 0.6 to 97 months after transplant. There were 22/42 (52.4%) cases of viral infections, 11/42 (26.2%) of fungal infections, 5/42 (11.9%) of bacterial infections and 4/42 (9.5%) of probable viral/bacterial etiology. Clinical presentation was meningitis/encephalitis in 25 cases (59.5%) and brain-space occupying lesions in 17 cases (40.5%). Twenty-three cases (60.5%) were considered opportunistic infections. Diagnosis were achieved mainly by brain biopsy/necropsy (15/42, 36%) or by cerebrospinal fluid analysis (20/42, 48%). Up to 40% of cases (17/42) had concurrent extra-neurological disease localizations. Overall, 90-day mortality rate was 29.0% (73.0% for fungal, 14.0% for viral and 11.0% for bacterial and probable infections, p<0.0001).

CONCLUSIONS

CNS infections were rare in the STCS, with viral meningoencephalitis being the most common disease. Fungal infections were associated with a high mortality.

Let's talk about Sex Characteristics - as a Risk Factor for Invasive Fungal Diseases

Biological sex, which comprises differences in host sex hormone homeostasis and immune responses, can have a substantial impact on the epidemiology of infectious diseases. Comprehensive data on sex distributions in invasive fungal diseases (IFDs) is lacking. In this review we performed a literature search of in vitro/animal studies, clinical studies, systematic reviews, and meta-analyses of invasive fungal infections. Females represented 51.2% of invasive candidiasis cases, mostly matching the proportions of females among the general population in the United States and Europe (>51%). In contrast, other IFDs were overrepresented in males, including invasive aspergillosis (51% males), mucormycosis (60%), cryptococcosis (74%), coccidioidomycosis (70%), histoplasmosis (61%), and blastomycosis (66%). Behavioral variations, as well as differences related to biological sex, may only in part explain these findings. Further investigations concerning the association between biological sex/gender and the pathogenesis of IFDs is warranted.

Comparison of the Performance of Two Galactomannan Detection Tests: Platelia Aspergillus Ag and Aspergillus Galactomannan Ag Virclia Monotest

The use of nonculture-based biomarkers such as the determination of galactomannan is sought for the diagnosis of invasive aspergillosis. To investigate the comparative yield of two tests for the detection of galactomannan in patients with or without proven or probable invasive aspergillosis. Overall, 327 samples (327 patients) were analyzed in a retrospective/prospective study performed in 3 hospitals in Madrid, comparing the determination results in serum or bronchoalveolar lavage of two techniques for galactomannan detection, namely, Platelia Aspergillus Ag (Bio-Rad) and Aspergillus galactomannan Ag Virclia Monotest (Vircell S.L.), following the manufacturer's instructions. Both techniques can automate the process, but the second technique has the advantage of individual processing and assembly of each sample without the need for the additional expense of single-dose strips in controls. In total, 288 of the 327 tests performed showed concordant results between both techniques. The agreement between both methods was к = 0.722, and the correlation between indices was ρ = 0.718. Only 39 samples showed discordant results. In those 39 cases, there were 15 patients with proven or probable invasive aspergillosis criteria. For the samples with clinical criteria as a reference, the areas under the curve of the receiver operating characteristic (ROC) curve were 0.962 for Platelia and 0.968 for VirClia. The VirClia test has been proven to be an alternative for diagnosis due to its friendlier automated format than that of the usual Platelia routine test. The VirClia test also allows individual action and, therefore, a more immediate clinical response. IMPORTANCE Invasive mycoses are increasingly present in immunosuppressed or hospitalized patients with serious illnesses, leading to high rates of morbidity and mortality. Invasive aspergillosis is an infection caused, in a percentage greater than 50%, by the genus Aspergillus. It is vitally important to make an early diagnosis that leads to the application of antifungals in the initial stage of the infection. Therefore, tools are required to help with the early diagnosis of the infection. This comparative study of two enzyme immunoassays is based on the detection of galactomannan antigen in serum and bronchoalveolar lavage samples. A new design based on chemiluminescence and presented in an automated single-dose format is compared to a conventional ELISA technique marketed for years. The results obtained from the prospective and retrospective study indicate a high correlation and degree of agreement between both techniques, as well as in their diagnostic performance.

Aspergillosis: Emerging risk groups in critically ill patients

Information on invasive aspergillosis (IA) and other invasive filamentous fungal infections is limited in non-neutropenic patients admitted to the intensive care unit (ICU) and presenting with no classic IA risk factors. This review is based on the critical appraisal of relevant literature, on the authors' own experience and on discussions that took place at a consensus conference. It aims to review risk factors favoring aspergillosis in ICU patients, with a special emphasis on often overlooked or neglected conditions. In the ICU patients, corticosteroid use to treat underlying conditions such as chronic obstructive pulmonary disease (COPD), sepsis, or severe COVID-19, represents a cardinal risk factor for IA. Important additional host risk factors are COPD, decompensated cirrhosis, liver failure, and severe viral pneumonia (influenza, COVID-19). Clinical observations indicate that patients admitted to the ICU because of sepsis or acute respiratory distress syndrome are more likely to develop probable or proven IA, suggesting that sepsis could also be a possible direct risk factor for IA, as could small molecule inhibitors used in oncology. There are no recommendations for prophylaxis in ICU patients; posaconazole mold-active primary prophylaxis is used in some centers according to guidelines for other patient populations and IA treatment in critically ill patients is basically the same as in other patient populations. A combined evaluation of clinical signs and imaging, classical biomarkers such as the GM assay, and fungal cultures examination, remain the best option to assess response to treatment.

LAY SUMMARY

The use of corticosteroids and the presence of co-morbidities such as chronic obstructive pulmonary disease, acute or chronic advanced liver disease, or severe viral pneumonia caused by influenza or Covid-19, may increase the risk of invasive aspergillosis in intensive care unit patients.

Invasive pulmonary aspergillosis in solid-organ transplant patients in the intensive care unit

INTRODUCTION

Solid-organ transplantation (SOT) is a well-known risk factor for invasive pulmonary aspergillosis (IPA). We report on the epidemiology and outcome of SOT patients with IPA in an intensive care unit (ICU) setting.

METHODS

This is a secondary study based on a subset of SOT patients from a prospective observational multicenter cohort (the AspICU project) including ICU patients with at least one Aspergillus spp. positive culture. Cases were classified as proven, probable, or putative IPA, or as Aspergillus-colonized. Mortality was reported at 12 weeks.

RESULTS

The study included 52 SOT patients (of which 18 lung, 17 liver, 12 kidney, and five heart transplants). Sixteen patients had proven IPA, 28 were categorized as putative IPA (of which only five reached a probable IPA diagnosis according to the European Organization for Research and Treatment of Cancer/Mycosis Study Group and Research Consortium criteria), and eight as Aspergillus-colonization. Among patients with IPA, 20 (45.5%) developed IPA during their ICU stay following transplantation whereas 24 patients (54.5%) had a medical ICU admission. Regarding medical imaging, nearly all IPA cases presented with non-specific findings as only nine demonstrated robust findings suggestive for invasive fungal disease. Overall, severity of the disease was reflected by a high prevalence of underlying conditions and acute organ derangements. Mortality among patients with IPA was 68%. Lung transplantation was associated with better survival (50%).

CONCLUSION

IPA in SOT patients in the ICU develops in the presence of overall high severity of the disease. It rarely presents with suggestive medical imaging thereby hampering diagnosis. IPA in ICU patients with SOT carries a grim prognosis.

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.

In Vitro Activity of APX2041, a New Gwt1 Inhibitor, and In Vivo Efficacy of the Prodrug APX2104 against Aspergillus fumigatus

Invasive aspergillosis (IA) due to Aspergillus fumigatus is a deadly infection for which new antifungal therapies are needed. Here, we demonstrate the efficacy of a Gwt1 inhibitor, APX2041, and its prodrug, APX2104, against A. fumigatus. The wild-type, azole-resistant, and echinocandin-resistant A. fumigatus strains were equally susceptible to APX2041 in vitro. APX2104 treatment in vivo significantly prolonged survival of neutropenic mice challenged with the wild-type and azole-resistant strains, revealing APX2104 as a potentially promising therapeutic against IA.

Central nervous system infections after solid organ transplantation

PURPOSE OF REVIEW

Significant advances to our understanding of several neuroinfectious complications after a solid organ transplant (SOT) have occurred in the last few years. Here, we review the central nervous system (CNS) infections that are relevant to SOT via a syndromic approach with a particular emphasis on recent updates in the field.

RECENT FINDINGS

A few key studies have advanced our understanding of the epidemiology and clinical characteristics of several CNS infections in SOT recipients. Risk factors for poor prognosis and protective effects of standard posttransplant prophylactic strategies have been better elucidated. Newer diagnostic modalities which have broad clinical applications like metagenomic next-generation sequencing, as well as those that help us better understand esoteric concepts of disease pathogenesis have been studied. Finally, several studies have provided newer insights into the treatment of these diseases.

SUMMARY

Recent findings reflect the steady progress in our understanding of CNS infections post SOT. They provide several avenues for improvement in the prevention, early recognition, and therapeutic outcomes of these diseases.

Fungal pneumonia in kidney transplant recipients

Fungal pneumonia is a dreaded complication encountered after kidney transplantation, complicated by increased mortality and often associated with graft failure. Diagnosis can be challenging because the clinical presentation is non-specific and diagnostic tools have limited sensitivity and specificity in kidney transplant recipients and must be interpreted in the context of the clinical setting. Management is difficult due to the increased risk of dissemination and severity, multiple comorbidities, drug interactions and reduced immunosuppression which should be applied as an important adjunct to therapy. This review will focus on the main causes of fungal pneumonia in kidney transplant recipients including Pneumocystis, Aspergillus, Cryptococcus, mucormycetes and Histoplasma. Epidemiology, clinical presentation, laboratory and radiographic features, specific characteristics will be discussed with an update on diagnostic procedures and treatment.