The 2015 International Society for Heart and Lung Transplantation Guidelines for the management of fungal infections in mechanical circulatory support and cardiothoracic organ transplant recipients: Executive summary

Fungal colonization before or after lung transplantation has no negative impact on survival or the development of chronic lung allograft dysfunction

Introduction

Long-term survival following lung transplantation (LTx) faces impediments due to chronic lung allograft dysfunction (CLAD), while infections hinder short-term survival. Fungal colonization and invasive fungal infections (IFI) are common within the first year after LTx. There is ongoing debate regarding the impact of such events on CLAD development and mortality. This study aims to investigate this matter further.

Methods

A total of 134 LTx recipients transplanted between 2011 and 2020 were included. The median follow-up time was 3.9 years. Fungal colonization and IFI were defined according to international consensus guidelines and were noted if present within the first 12 months after LTx.

Results

Postoperative fungal colonization was found in 101 patients, and 14 patients had an IFI within twelve months of transplantation. Nineteen patients were neither colonized nor infected. Out of the 115 patients with colonization or IFI, 61 patients had growth of a yeast such as Candida species (spp.). Fifty-six patients were colonized prior to LTx. Being colonized with fungus before or within the first 12 months post-LTx did not significantly affect survival or CLAD development.

Conclusions

The results of the current study indicate that fungal colonization either pre-transplantation or within the first 12 months after does not correlate with increased risks of mortality or CLAD development. These findings show that while fungal colonization is a common occurrence in LTx recipients, it does not predispose the patients of the cohort to adverse outcomes.

Clinical Significance and Therapeutic Challenges of Scedosporium spp. and Lomentospora prolificans Isolates in a Single-Center Cohort of Lung Transplant Recipients

(1) Background: Emerging fungal infections associated with Scedosporium spp. and Lomentospora prolificans (S/L) are becoming more frequent and are very difficult to treat. Our objective was to analyze the frequency and management of S/L isolates in lung transplant (LTx) recipients, the patient outcomes and in vitro antifungal sensitivity. (2) Methods: We included all patients with S/L isolation during post-transplant follow-up. Data were collected from electronic medical records. All samples were cultivated on Sabouraud Chloramphenicol agar. Isolations of S/L were submitted to in vitro susceptibility tests. (3) Results: A total of 11 (2%) of the 576 LTx recipients included had at least one isolation of S/L. Classification for the 11 cases were colonization (4; 36%) and infection (7; 65%). Five infections were pulmonary (71%) and two were disseminated (29%). S. apiospermum complex was the most frequently occurring isolation in patients with pulmonary disease while L. prolificans was the most frequent in patients with disseminated disease. Ten patients were treated. The most frequent antifungal drugs used were voriconazole (n = 8) and terbinafine (n = 6). Seven patients (70%) received more than one drug. The mortality rate associated with L. prolificans isolation was 50% for colonization and 100% for disseminated disease. (4) Conclusions: Scedosporium spp. and L. prolificans infections are associated with high morbidity and mortality rates. New diagnostic and therapeutic tools are required to reduce the impact of these infections.

Aspergillus After Lung Transplantation: Prophylaxis, Risk Factors, and the Impact on Chronic Lung Allograft Dysfunction

BACKGROUND

Invasive pulmonary aspergillosis (IA) poses significant challenges for lung transplant (LTx) patients, with unclear risk factors and preventive strategies. The effectiveness of nebulized amphotericin B (AmB) or statins for IA prevention and the effect of IA on chronic lung allograft dysfunction (CLAD) and mortality remain questionable.

METHODS

Data were collected from all LTx patients transplanted between December 1, 2013 and January 1, 2022 at the University Medical Center Groningen. IA, was defined according to published criteria. Prespecified risk factors were compared between patients with and without IA post-LTx and were entered in a logistic regression model. Two additional logistic regression models were built with factors that might be associated with statin or AmB prophylaxis and IA. A matched case-control study was conducted for the association between statins and IA, with matching based on follow-up time.

RESULTS

Aspergillus was cultured in 110 /274 (40%) patients post-LTx and 89/110 (81%) were classified as probable IA. MMF use, airway stenosis, Aspergillus cultured pre-LTx, CLAD, and acute rejection (AR), were significantly associated with IA. Statin use was associated with a lower incidence of IA, while AmB prophylaxis showed no significant effect. A significant statin effect could not be confirmed by the case control analysis. There was no significant difference in all-cause mortality between patients with and without IA (34% vs. 29%).

CONCLUSIONS

The high incidence of IA post-LTx necessitates more effective strategies. Key targets for intervention include prior positive cultures, airway stenosis, AR, and the use of MMF. The role of statins remains unclear and requires further research.

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.

Risk Factors and Outcomes of Invasive Candida Infections in Heart Transplant Recipients: A Case-Control Study

BACKGROUND

Invasive Candida infections (ICI) are the most common invasive fungal infections in solid organ transplant recipients. There are limited contemporary data on the risk factors for infection in heart transplant (HT) recipients especially since the expansion of temporary mechanical circulatory support (MCS) use.

METHODS

This was a case-control study conducted at a tertiary care academic hospital of HT recipients from January 2022 to January 2024. All patients who developed ICI by the detection of Candida species from a normally sterile site were included as cases. Four controls who underwent HT, two before the case and two after the case, were selected. ​Fisher's exact or Mann-U-Whitney tests were used for the analysis.

RESULTS

There were 12 cases and 48 controls out of a total of 117 transplants during the study period​. The proportion of ICI was 10.6%. The median time to ICI from transplant was 16 days (IQR 10, 83). The most common organisms isolated were Candida parapsilosis and Candida albicans. The majority of infections were mediastinitis. Risk factors for ICI included receipt of antibiotics for more than 7 days within 1 month prior to transplant (58.3% vs. 22.9%, p = 0.03), tracheostomy (41.7% vs. 10.4%, p = 0.02), prolonged chest tube placement (13 vs. 9 days, p = 0.02), and temporary MCS (p = 0.042). Patients who developed ICI had increased 90-day all-cause mortality compared to controls (33.3% vs. 4.2%, p = 0.01).

CONCLUSION

This study identified several risk factors for ICI following HT. Further research is essential to develop interventions that mitigate these risk factors in this patient population.

Comprehensive Review of Environmental Surveillance for Azole-Resistant Aspergillus fumigatus: A Practical Roadmap for Hospital Clinicians and Infection Control Teams

As azole-resistant Aspergillus fumigatus emerges globally, healthcare facilities face mounting challenges in managing invasive aspergillosis. This review synthesizes worldwide azole resistance data to reveal profound regional variability, demonstrating that findings from other regions cannot be directly extrapolated to local settings. Consequently, hospital-level environmental surveillance is crucial for tailoring interventions to local epidemiology and detecting resistant strains in real-time. We outline practical approaches-encompassing sampling site prioritization, diagnostic workflows (culture-based and molecular), and PDCA-driven continuous improvement-so that even resource-limited facilities can manage resistant isolates more effectively. By linking real-time surveillance findings with clinical decisions, hospitals can tailor antifungal stewardship programs and swiftly adjust prophylaxis or treatment regimens. Our approach aims to enable accurate, ongoing evaluations of emerging resistance patterns, ensuring that institutions maintain efficient and adaptive programs. Ultimately, we advocate for sustained, collaborative efforts worldwide, where facilities adapt protocols to local conditions, share data through international networks, and contribute to a global knowledge base on resistance mechanisms. Through consistent application of these recommendations, healthcare systems can better preserve azole efficacy, safeguard immunocompromised populations, and refine infection control practices in the face of evolving challenges.

A 2-year Review of the Diagnostic Performance of Serum and Bronchoalveolar Lavage Galactomannan Testing in Lung Transplant Recipients in a National Heart and Lung Transplant Centre

BACKGROUND

The 2015 International Society for Heart and Lung Transplant (ISHLT) fungal guidelines recommend the use of bronchoalveolar lavage (BAL) galactomannan over serum galactomannan for the diagnosis of invasive aspergillosis (IA) in lung transplant (LTx) recipients, based on limited evidence. Galactomannan testing is costly.

METHODS

A single-center, retrospective cohort study reviewing all 814 serum and BAL galactomannan samples received from 184 LTx recipients in our center between 2021 and 2022 and assessing their diagnostic performance in the diagnosis of IA.

RESULTS

Over the study period, 394 serum galactomannan samples were received from 144 patients and 420 BAL galactomannan samples from 143 patients. Using a cut-off of ≥ 1.0 for BAL galactomannan, the sensitivity and specificity were 65.9% and 98.4%, respectively. In total, 30 patients had positive BAL galactomannan. Antifungal therapy was commenced or continued in 29 of these patients either as targeted or pre-emptive treatment. Using a cut-off of ≥ 0.5 for serum galactomannan, the sensitivity and specificity were 9.7% and 99.7%, respectively. In total, four patients had a positive serum galactomannan. All four patients were either already on antifungal treatment for IA or were started before the serum galactomannan result was available, supported by laboratory, clinical, and radiological findings. A positive serum galactomannan was used to monitor treatment response in one patient.

CONCLUSION

Serum galactomannan is not a valuable test in the diagnosis of IA in our LTx recipients, is costly, and does not remove the need for bronchoscopy and BAL galactomannan. This supports the ISHLT recommendation.

Left Ventricular 3-Dimensional Global Longitudinal Strain Predicts All-Cause Mortality in Patients With Heart Transplant

BACKGROUND

The prognostic value of 3-dimensional (3D)-left ventricular global longitudinal strain (LVGLS) in recipients of heart transplant (HT) reremains unknown. This study aimed to determine whether 3D-LVGLS was the more powerful predictor of poor outcomes in recipients of HT compared with 2-dimensional (2D)-LVGLS.

METHODS AND RESULTS

All consecutive adult patients who received HT and underwent at least 1 comprehensive 2D and 3D transthoracic echocardiographic examination for clinical surveillance were retrospectively enrolled. The end point was all-cause mortality. Prognostic model performance was assessed according to the C-statistic. The 3D-LVGLS measurements were feasible in 294 of 342 patients with HT (86%). The median follow-up time was 53 months, and 44 HT redied. Receiver operating characteristic curves revealed that the area under the curve for predicting all-cause mortality was greater for 3D-LVGLS than 2D-LVGLS (0.77 versus 0.67, P=0.012). When HT stratified patients with HT into tertiles according to 3D-LVGLS values, patients with lower 3D-LVGLS had worse outcome (P<0.001). The multivariable Cox analysis showed that the model with 3D-LVGLS (hazard ratio [HR],1.44 [95% CI,1.24-1.68]; P<0.001; C-statistic=0.814) was better in predicting death than the model with 2D-LVGLS (HR, 1.19 [95% CI, 1.06-1.32]; P=0.002; C-statistic=0.772). The best cutoff value of 3D-LVGLS for detecting all-cause mortality was -16.1%, with a sensitivity of 63.6% and a specificity of 84.0%.

CONCLUSIONS

The 3D-LVGLS was a powerful predictor of all-cause mortality in patients receiving HT and provided greater prognostic value than 2D-LVGLS. Our study highlighted the potential of evaluating 3D-LVGLS for risk stratification in recipients of HT.

Unraveling the spectrum of airway complications following lung transplantation: a comprehensive overview

PURPOSE OF REVIEW

This review delves into the intricate landscape of airway complications post lung transplantation. With the rising prevalence of end-stage lung disease and the increasing number of lung transplantation worldwide, understanding and effectively managing airway complications are crucial. Given the nuanced nature of these complications and the array of treatment options available, this review aims to provide a comprehensive overview of how to identify, classify, mitigate risk factors for, and manage these complications.

RECENT FINDINGS

Several donor, recipient, and surgical risk factors are associated with the increased risk of airway complications. In managing these complications, bronchoscopic interventions, notably balloon dilation and stenting, are pivotal. Although self-expanding metallic stents offer versatility, silicone stents are preferred in certain scenarios for their durability. Emerging techniques such as biodegradable stents and advancing imaging modalities show promise in mitigating complications and improving outcomes.

SUMMARY

These findings underscore the significance of a multidisciplinary approach and personalized treatment algorithms in managing airway complications post lung transplantation. By elucidating specific indications and complications of treatment modalities, this review serves as a valuable resource for optimally managing airway complications. Ongoing research into novel interventions holds promise for further enhancing outcomes in this challenging clinical setting.

Bridging Echinocandin With Azole Antifungal Therapy on Prevention of Invasive Candidiasis Post-Lung Transplantation

Background

Invasive candidiasis (IC) is a significant factor for lung transplant recipient (LTR) mortality, especially in the immediate postoperative phase. Receipt of antifungal prophylaxis has demonstrated lower all-cause mortality.

Methods

This was a single-center, retrospective cohort study of LTRs between August 2017 and August 2020. Included patients were adult LTRs with positive Candida cultures preoperatively (donor or recipient) or within 6 weeks postoperatively. Patients were divided into 2 cohorts-bridged and unbridged. The bridged cohort received micafungin in the postoperative period until therapeutic azole concentrations were achieved or up to 2 weeks, whichever was sooner. The primary outcome was a composite of proven or probable invasive candidiasis.

Results

A total of 117 patients were included in the study, with 68 in the unbridged cohort and 49 in the bridged cohort. There were more cases of IC in the bridged cohort than in the unbridged cohort (P = .011).

Conclusions

In combination with an azole antifungal, micafungin did not prevent IC in postoperative LTRs with cultures positive for Candida species in this cohort. Larger prospective studies are needed to determine the ideal combination and duration of antifungal prophylaxis.

Novel antifungals and treatment approaches to tackle resistance and improve outcomes of invasive fungal disease

SUMMARYFungal infections are on the rise, driven by a growing population at risk and climate change. Currently available antifungals include only five classes, and their utility and efficacy in antifungal treatment are limited by one or more of innate or acquired resistance in some fungi, poor penetration into "sequestered" sites, and agent-specific side effect which require frequent patient reassessment and monitoring. Agents with novel mechanisms, favorable pharmacokinetic (PK) profiles including good oral bioavailability, and fungicidal mechanism(s) are urgently needed. Here, we provide a comprehensive review of novel antifungal agents, with both improved known mechanisms of actions and new antifungal classes, currently in clinical development for treating invasive yeast, mold (filamentous fungi), Pneumocystis jirovecii infections, and dimorphic fungi (endemic mycoses). We further focus on inhaled antifungals and the role of immunotherapy in tackling fungal infections, and the specific PK/pharmacodynamic profiles, tissue distributions as well as drug-drug interactions of novel antifungals. Finally, we review antifungal resistance mechanisms, the role of use of antifungal pesticides in agriculture as drivers of drug resistance, and detail detection methods for antifungal resistance.

Management of infectious disease syndromes in thoracic organ transplants and mechanical circulatory device recipients: a Delphi panel

PURPOSE

Antimicrobial misuse contributes to antimicrobial resistance in thoracic transplant (TTx) and mechanical circulatory support (MCS) recipients. This study uses a modified Delphi method to define the expected appropriate antimicrobial prescribing for the common clinical scenarios encountered in TTx and MCS recipients.

METHODS

An online questionnaire on managing 10 common infectious disease syndromes was submitted to a multidisciplinary Delphi panel of 25 experts from various disciplines. Consensus was predefined as 80% agreement for each question. Questions where consensus was not achieved were discussed during live virtual live sessions adapted by an independent process expert.

RESULTS

An online survey of 62 questions related to 10 infectious disease syndromes was submitted to the Delphi panel. In the first round of the online questionnaire, consensus on antimicrobial management was reached by 6.5% (4/62). In Round 2 online live discussion, the remaining 58 questions were discussed among the Delphi Panel members using a virtual meeting platform. Consensus was reached among 62% (36/58) of questions. Agreement was not reached regarding the antimicrobial management of the following six clinical syndromes: (1) Burkholderia cepacia pneumonia (duration of therapy); (2) Mycobacterium abscessus (intra-operative antimicrobials); (3) invasive aspergillosis (treatment of culture-negative but positive BAL galactomannan) (duration of therapy); (4) respiratory syncytial virus (duration of antiviral therapy); (5) left ventricular assist device deep infection (initial empirical antimicrobial coverage) and (6) CMV (duration of secondary prophylaxis).

CONCLUSION

This Delphi panel developed consensus-based recommendations for 10 infectious clinical syndromes seen in TTx and MCS recipients.

A novel approach to reducing hepatotoxicity related to fungal prophylaxis in pediatric lung transplant recipients

BACKGROUND

Pediatric lung transplant patients are at risk for developing invasive fungal infections post-transplant. No consensus exists on optimal antifungal regimens and voriconazole, a common first-line agent, has been shown to cause hepatotoxicity. We describe a single-center experience utilizing a novel antifungal regimen of intravenous micafungin and nebulized amphotericin B immediately post-transplant with conversion to an azole at the time of hospital discharge and compare it to a historical cohort of patients who received voriconazole monotherapy throughout their immediate post-operative course.

METHODS

This is a retrospective review of patients in the age 0-18 who received a lung transplant from June 2016-May 2021. Data points collected included: demographic data, transplant date and discharge date, Aspergillus colonization, type of lung transplant, hospitalization and level of care information, induction and antifungal medication regimen; AST, ALT, GGT, bilirubin, and direct bilirubin at various timepoints; and respiratory and blood culture results. The two patient groups were compared by assessment of changes in LFTs and culture results.

RESULTS

Forty-two patients were included in the analysis, with 24 patients receiving micafungin and nebulized amphotericin and 18 patients receiving voriconazole. All patients in both groups experienced a post-operative elevation in at least one transaminase or bilirubin. More patients in the micafungin/amphotericin group had resolution of all abnormal LFTs by 1 month post-transplant (p = .036). Additionally, patients in the micafungin/amphotericin group experienced faster normalization of their LFTs compared with the voriconazole group (p < .001). Ten patients in the micafungin/amphotericin group and five patients in the voriconazole group were found to have fungal growth on culture post-transplant, but this difference was not found to be statistically significant (p = .507).

CONCLUSIONS

An antifungal regimen of micafungin and nebulized amphotericin B liposomal may be useful at decreasing the duration of elevated liver enzymes in pediatric patients in the immediate post-lung transplant period when compared with voriconazole monotherapy. Larger prospective studies looking at antifungal regimens in pediatric patients post-lung transplant are warranted.

Identification of Irpex and Rhodotorula on surveillance bronchoscopy in a pediatric lung transplant recipient: A case report and review of literature of these atypical fungal organisms

BACKGROUND

Invasive fungal disease (IFD) is a frequent complication in pediatric lung transplant recipients, occurring in up to 12% of patients in the first year. Risk factors for infection include impaired lung defenses and intense immunosuppressive regimens. While most IFD occurs from Aspergillus, other fungal conidia are continuously inhaled, and infections with fungi on a spectrum of human pathogenicity can occur.

CASE REPORT

We report a case of a 17-year-old lung transplant recipient in whom Irpex lacteus and Rhodotorula species were identified during surveillance bronchoscopy. She was asymptomatic and deemed to be colonized by Irpex lacteus and Rhodotorula species following transplant. 2 years after transplantation, she developed a fever, respiratory symptoms, abnormal lung imaging, and histological evidence of acute and chronic bronchitis on transbronchial biopsy. After developing symptoms concerning for a pulmonary infection and graft dysfunction, she was treated for a presumed IFD. Unfortunately, further diagnostic testing could not be performed at this time given her tenuous clinical status. Despite the initiation of antifungal therapy, her graft function continued to decline resulting in a second lung transplantation.

CONCLUSIONS

This case raises the concern for IFD in lung transplant recipients from Irpex species. Further investigation is needed to understand the pathogenicity of this organism, reduce the incidence and mortality of IFD in lung transplant recipients, and refine the approach to diagnosis and manage the colonization and isolation of rare, atypical fungal pathogens in immunocompromised hosts.

Risk Factors for Invasive Fungal Infection in Lung Transplant Recipients on Universal Antifungal Prophylaxis

Background

Many centers use universal antifungal prophylaxis after lung transplant, but risk factors for invasive fungal infection (IFI) in this setting are poorly described.

Methods

This retrospective, single-center cohort study including 603 lung transplant recipients assessed risk factors for early (within 90 days of transplant) invasive candidiasis (IC) and invasive mold infection (IMI) and late (90-365 days after transplant) IMI using Cox proportional hazard regression.

Results

In this cohort, 159 (26.4%) patients had 182 IFIs. Growth of yeast on donor culture (hazard ratio [HR], 3.30; 95% CI, 1.89-5.75) and prolonged length of stay (HR, 1.02; 95% CI, 1.01-1.03) were associated with early IC risk, whereas transplantation in 2016 or 2017 (HR, 0.21; 95% CI, 0.06-0.70; HR, 0.25; 95% CI, 0.08-0.80, respectively) and female recipient sex (HR, 0.53; 95% CI, 0.30-0.93) were associated with reduced risk. Antimold therapy (HR, 0.21; 95% CI, 0.06-0.78) was associated with lower early IMI risk, and female donor sex (HR, 0.40; 95% CI, 0.22-0.72) was associated with lower late IMI risk. Recent rejection was a risk factor for late IMI (HR, 1.73; 95% CI, 1.02-2.95), and renal replacement therapy predisposed to early IC, early IMI, and late IMI (HR, 5.67; 95% CI, 3.01-10.67; HR, 7.54; 95% CI, 1.93-29.45; HR, 5.33; 95% CI, 1.46-19.49, respectively).

Conclusions

In lung transplant recipients receiving universal antifungal prophylaxis, risk factors for early IC, early IMI, and late IMI differ.

Immune outcomes of lung transplant recipients with different cytochrome P450 3A5 phenotypes after discontinuation of voriconazole antifungal prophylaxis

INTRODUCTION

Tacrolimus forms the backbone of immunosuppression regimens in lung transplant recipients (LTRs). It is extensively metabolized by cytochrome P450 (CYP) 3A5 enzymes, of which polymorphisms can significantly affect tacrolimus dose requirements. It is unknown how coadministration of tacrolimus with voriconazole, a potent CYP3A5 inhibitor, affects rejection rates or empiric dose adjustments needed after voriconazole discontinuation.

METHODS

This retrospective cohort study compares LTRs with poor (PR) versus intermediate/extensive (IE) CYP3A5 metabolizer phenotypes. The primary endpoint is cumulative immune outcomes within three months of voriconazole discontinuation; secondary endpoints include change in tacrolimus dose-to-concentration ratios after voriconazole discontinuation.

RESULTS

Thirty-four patients underwent full analysis: 13 IE and 21 PR metabolizers. A higher proportion of IE metabolizers were African American (46.2% vs. 9.5%, p = .03). There was no significant difference in composite immune outcomes, though there was a proportionally higher frequency of new donor-specific antibody development in PR metabolizers (14.3% vs 7.7%, p = .56). Both groups required approximately 2.5 to 3-fold tacrolimus dose increases post-voriconazole discontinuation to re-attain therapeutic levels.

CONCLUSION

This novel investigation sheds light on how CYP3A5 phenotype could be used to guide tacrolimus dosing, with the goal of preventing both toxicity and organ rejection.

Beginners guide to protocol writing in transplant infectious diseases

Creating protocols surrounding the guidance of the prevention and treatment of infections in transplantation is an integral part of being a transplant infectious disease physician. This piece outlines the key components for success in developing a protocol, with an example protocol and protocol template available for readers. Collaborating effectively within the multi-disciplinary team to develop, implement, and assess the efficacy of a protocol is a skill that enhances the relationship with our transplantation colleagues and improves patient outcomes by standardizing the care delivered.

Thrombotic and Hemorrhagic Complications Following Left Ventricular Assist Device Placement: An Emphasis on Gastrointestinal Bleeding, Stroke, and Pump Thrombosis

The left ventricular assist device (LVAD) is a mechanical circulatory support device that supports the heart failure patient as a bridge to transplant (BTT) or as a destination therapy for those who have other medical comorbidities or complications that disqualify them from meeting transplant criteria. In patients with severe heart failure, LVAD use has extended survival and improved signs and symptoms of cardiac congestion and low cardiac output, such as dyspnea, fatigue, and exercise intolerance. However, these devices are associated with specific hematologic and thrombotic complications. In this manuscript, we review the common hematologic complications of LVADs.

Outbreaks of Fungal Infections in Hospitals: Epidemiology, Detection, and Management

Nosocomial clusters of fungal infections, whilst uncommon, cannot be predicted and are associated with significant morbidity and mortality. Here, we review reports of nosocomial outbreaks of invasive fungal disease to glean insight into their epidemiology, risks for infection, methods employed in outbreak detection including genomic testing to confirm the outbreak, and approaches to clinical and infection control management. Both yeasts and filamentous fungi cause outbreaks, with each having general and specific risks. The early detection and confirmation of the outbreak are essential for diagnosis, treatment of affected patients, and termination of the outbreak. Environmental sampling, including the air in mould outbreaks, for the pathogen may be indicated. The genetic analysis of epidemiologically linked isolates is strongly recommended through a sufficiently discriminatory approach such as whole genome sequencing or a method that is acceptably discriminatory for that pathogen. An analysis of both linked isolates and epidemiologically unrelated strains is required to enable genetic similarity comparisons. The management of the outbreak encompasses input from a multi-disciplinary team with epidemiological investigation and infection control measures, including screening for additional cases, patient cohorting, and strict hygiene and cleaning procedures. Automated methods for fungal infection surveillance would greatly aid earlier outbreak detection and should be a focus of research.

Risk factors and prognosis of airway complications in lung transplant recipients: A systematic review and meta-analysis

BACKGROUND

Airway complications (AC) are one of leading causes of morbidity and mortality after lung transplant (LTx), but their predictors and outcomes remain controversial. This study aimed to identify potential risk factors and prognosis of AC.

METHODS

A systematic review was performed by searching PubMed, Embase, and Cochrane Library. All observational studies reporting outcome and potential factors of AC after LTx were included. The incidence, mortality, and estimated effect of each factor for AC were pooled by using the fixed-effects model or random-effects model.

RESULTS

Thirty-eight eligible studies with 52,116 patients undergoing LTx were included for meta-analysis. The pooled incidence of AC was 12.4% (95% confidence interval [CI] 9.5-15.8) and the mean time of occurrence was 95.6 days. AC-related mortality rates at 30-days, 90-days, 6 months, 1 year, and 5 years were 6.7%, 17.9%, 18.2%, 23.6%, and 66.0%, respectively. Airway dehiscence was the most severe type with a high mortality at 30 days (60.9%, 95% CI 20.6-95.2). We found that AC was associated with a higher risk of mortality in LTx recipients (hazard ratio [HR] 1.71, 95% CI 1.04-2.81). Eleven significant predictors for AC were also identified, including male donor, male recipient, diagnosis of COPD, hospitalization, early rejection, postoperative infection, extracorporeal membrane oxygenation, mechanical ventilation, telescopic anastomosis, and bilateral and right-sided LTx.

CONCLUSION

AC was significantly associated with higher mortality after LTx, especially for dehiscence. Targeted prophylaxis for modifiable factors and enhanced early bronchoscopy surveillance after LTx may improve the disease burden of AC.

Real-world Use of Mold-Active Triazole Prophylaxis in the Prevention of Invasive Fungal Diseases: Results From a Subgroup Analysis of a Multicenter National Registry

Background

Antifungal prophylaxis can prevent invasive fungal diseases (IFDs) in high-risk, immunocompromised patients. This study assessed the real-world use of mold-active triazoles (MATs) for the prevention of IFDs.

Methods

This subgroup analysis of a multicenter, observational, prospective registry in the United States from March 2017 to April 2020 included patients who received MATs for prophylaxis (isavuconazole, posaconazole, and voriconazole) at study index/enrollment. The primary objective was to describe patient characteristics and patterns of MAT use. Exploratory assessments included the frequency of breakthrough IFDs and MAT-related adverse drug reactions (ADRs).

Results

A total of 1177 patients (256 isavuconazole, 397 posaconazole, 272 voriconazole, and 252 multiple/sequenced MATs at/after index/enrollment) were included in the prophylaxis subgroup analysis. Patient characteristics were similar across MAT groups, but risk factors varied. Hematological malignancy predominated (76.5%) across all groups. Breakthrough IFDs occurred in 7.1% (73/1030) of patients with an investigator's assessment (5.0% [11/221] isavuconazole; 5.3% [20/374] posaconazole; 4.0% [9/226] voriconazole; and 15.8% [33/209] multiple/sequenced MATs). Aspergillus (29.5% [18/61]) and Candida (36.1% [22/61]) species were the most common breakthrough pathogens recovered. ADRs were reported in 14.1% of patients, and discontinuation of MATs due to ADRs was reported in 11.1% of patients (2.0% [5/245] isavuconazole; 8.2% [30/368] posaconazole; and 10.1% [27/267] voriconazole).

Conclusions

Breakthrough IFDs were uncommon in patients who received MATs for prophylaxis. Candida and Aspergillus species were the most commonly reported breakthrough pathogens. The discontinuation of MATs due to ADRs was infrequent. These findings support prophylactic strategies with isavuconazole, posaconazole, and voriconazole in high-risk patients.

Candidemia in thoracic solid organ transplant recipients: Characteristics and outcomes relative to matched uninfected and bacteremic thoracic organ transplant recipients

BACKGROUND

Little is understood about the risk factors and outcomes from candidemia in thoracic solid organ transplant recipients.

METHODS

This is a single-center retrospective cohort study of patients undergoing heart or lung transplant between January 1, 2013 and December 31, 2022. We performed two comparisons among heart and lung transplant recipients: (1) recipients with candidemia versus matched, uninfected recipients, and (2) recipients with candidemia versus recipients with bacteremia.

RESULTS

During the study 384 heart and 194 lung transplants were performed. Twenty-one (5.5%) heart and six (3.1%) lung recipients developed candidemia. Heart recipients with candidemia were more likely to have had delayed chest closure (38.1% vs. 0%, p < .0001), temporary mechanical circulatory support (57.1% vs. 11.9%, p = .0003), and repeat surgical chest exploration 76.2% vs. 16.7%, p < .0001) than uninfected controls. Heart and lung recipients who developed candidemia were more likely to have been on renal replacement therapy prior to infection relative to uninfected controls (57.1% vs. 11.9%, p = .0003 and 66.7% vs. 0%, p = .0041, respectively). Heart recipients with candidemia had significantly lower post-transplant survival and lower post-infection survival relative to matched uninfected controls and heart recipients with bacteremia, respectively (p < .0001 and p = .0002, respectively).

CONCLUSIONS

Candidemia following heart and lung transplantation is associated with significant morbidity and mortality. Further research is needed to understand if heart recipients with delayed chest closure, temporary mechanical circulatory support, renal replacement therapy, and repeat surgical chest exploration may benefit from targeted antifungal prophylaxis.

Dosing Optimization of Posaconazole in Lung-Transplant Recipients Based on Population Pharmacokinetic Model

Although posaconazole tablets show relatively low variability in pharmacokinetics (PK), the proportion of patients achieving the PK/PD target at the approved uniform dose for both prophylaxis and therapy is not satisfactory. The aim of this study was to develop a posaconazole population PK model in lung-transplant recipients and to propose a covariate-based dosing optimization for both prophylaxis and therapy. In this prospective study, 80 posaconazole concentrations obtained from 32 lung-transplant patients during therapeutic drug monitoring were analyzed using nonlinear mixed-effects modelling, and a Monte Carlo simulation was used to describe the theoretical distribution of posaconazole PK profiles at various dosing regimens. A one-compartment model with both linear absorption and elimination best fit the concentration-time data. The population apparent volume of distribution was 386.4 L, while an apparent clearance of 8.8 L/h decreased by 0.009 L/h with each year of the patient's age. Based on the covariate model, a dosing regimen of 200 mg/day for prophylaxis in patients ˃60 years, 300 mg/day for prophylaxis in patients ˂60 years and for therapy in patients ˃60 years, and 400 mg/day for therapy in patients ˂60 years has been proposed. At this dosing regimen, the PK/PD target for prophylaxis and therapy is reached in 95% and 90% of population, respectively, representing significantly improved outcomes in comparison with the uniform dose.

Decoding the Guidelines of Invasive Pulmonary Aspergillosis in Critical Care Setting: Imaging Perspective

Invasive pulmonary aspergillosis (IPA) is a common, life-threatening opportunistic fungal infection seen in susceptible individuals especially those admitted in critical care units. Multiple guidelines have been promulgated for the diagnosis of IPA, some of which are all inclusive, while others cater to specific patient groups. Microbiology forms the crux of the majority of the diagnostic tests/criteria; however, results take a considerable amount of time. Radiology can play an important role by bridging the gap to reach at an early diagnosis. Thus, the role of a radiologist cannot be overemphasized to recognize the typical and atypical imaging manifestations of invasive aspergillosis and aid in the swift management of these cases. This review decodes the terminology and various diagnostic criteria for IPA relevant to imaging studies. Further, the differences in imaging manifestations of IPA in neutropenic and non-neutropenic patients are also discussed.

Aspergillus Galactomannan Titer as a Diagnostic Marker of Invasive Pulmonary Aspergillosis in Lung Transplant Recipients: A Single-Center Retrospective Cohort Study

Invasive pulmonary aspergillosis (IPA) can occur in immunocompromised patients, and an early detection and intensive treatment are crucial. We sought to determine the potential of Aspergillus galactomannan antigen titer (AGT) in serum and bronchoalveolar lavage fluid (BALF) and serum titers of beta-D-glucan (BDG) to predict IPA in lung transplantation recipients, as opposed to pneumonia unrelated to IPA. We retrospectively reviewed the medical records of 192 lung transplant recipients. Overall, 26 recipients had been diagnosed with proven IPA, 40 recipients with probable IPA, and 75 recipients with pneumonia unrelated to IPA. We analyzed AGT levels in IPA and non-IPA pneumonia patients and used ROC curves to determine the diagnostic cutoff value. The Serum AGT cutoff value was 0.560 (index level), with a sensitivity of 50%, specificity of 91%, and AUC of 0.724, and the BALF AGT cutoff value was 0.600, with a sensitivity of 85%, specificity of 85%, and AUC of 0.895. Revised EORTC suggests a diagnostic cutoff value of 1.0 in both serum and BALF AGT when IPA is highly suspicious. In our group, serum AGT of 1.0 showed a sensitivity of 27% and a specificity of 97%, and BALF AGT of 1.0 showed a sensitivity of 60% and a specificity of 95%. The result suggested that a lower cutoff could be beneficial in the lung transplant group. In multivariable analysis, serum and BALF AGT, with a minimal correlation between the two, showed a correlation with a history of diabetes mellitus.

Clinical Uses of Inhaled Antifungals for Invasive Pulmonary Fungal Disease: Promises and Challenges

The role of inhaled antifungals for prophylaxis and treatment of invasive fungal pneumonias remains undefined. Herein we summarize recent clinically relevant literature in high-risk groups such as neutropenic hematology patients, including those undergoing stem cell transplant, lung and other solid transplant recipients, and those with sequential mold lung infections secondary to viral pneumonias. Although there are several limitations of the available data, inhaled liposomal amphotericin B administered 12.5 mg twice weekly could be an alternative method of prophylaxis in neutropenic populations at high risk for invasive fungal pneumonia where systemic triazoles are not tolerated. In addition, inhaled amphotericin B has been commonly used as prophylaxis, pre-emptive, or targeted therapy for lung transplant recipients but is considered as a secondary alternative for other solid organ transplant recipients. Inhaled amphotericin B seems promising as prophylaxis in fungal pneumonias secondary to viral pneumonias, influenza, and SARS CoV-2. Data remain limited for inhaled amphotericin for adjunct treatment, but the utility is feasible.

Lung allograft transbronchial cryobiopsy for critical ventilated patients: a randomised trial

BACKGROUND

Transbronchial lung cryobiopsy is an emerging technique for diagnosing pulmonary rejection. However, no prospective studies of this procedure for critically ill lung transplant recipients who require mechanical ventilation in the intensive care unit (ICU) have been performed.

METHODS

From March 2017 to January 2020, we performed a prospective, randomised, comparative study to assess the diagnostic yield, histological quality and safety of transbronchial lung biopsy using biopsy forceps, a 1.9-mm cryoprobe or a 2.4-mm cryoprobe.

RESULTS

89 out of 129 consecutive transbronchial biopsy procedures (forceps group, 28 procedures; 1.9-mm cryoprobe group, 31 procedures; 2.4-mm cryoprobe group, 30 procedures) were randomised. Compared with lung samples from the forceps and 1.9-mm cryoprobe groups, lung samples from the 2.4-mm cryoprobe group allowed the most definitive diagnoses (p<0.01 and p=0.02, respectively), the most diagnoses of acute lung rejection (p<0.01 and p=0.01, respectively) and the most diagnoses of rejection severity (p<0.01 and p<0.01, respectively). These samples were larger (p<0.01 and p=0.04, respectively), had the most adequate alveolar tissue (p<0.01 and p=0.02, respectively), had more vessels per procedure (p<0.01 and p=0.01, respectively) and had no significant crush artefacts. Moderate bleeding was observed in 23% of cases (p=0.01 and p=0.08, respectively). No severe bleeding was observed.

CONCLUSIONS

Transbronchial lung biopsy using a 2.4-mm cryoprobe allows the safe collection of lung tissue samples from critically ill lung transplant recipients who require mechanical ventilation in the ICU and has good diagnostic performance.

Fungal Tracheobronchitis in Lung Transplant Recipients: Incidence and Utility of Diagnostic Markers

Fungal tracheobronchitis caused by Aspergillus and Candida spp. is a recognized complication after lung transplantation, but knowledge of the incidence of Candida tracheobronchitis is lacking. The diagnosis relies on fungal cultures in bronchoalveolar lavage fluid (BALF), but cultures have low specificity. We aimed to evaluate the one-year incidence of fungal tracheobronchitis after lung transplantation and to assess the utility of diagnostic markers in serum and BALF to discriminate fungal tracheobronchitis from colonization. Ninety-seven consecutively included adult lung-transplant recipients were prospectively followed. BALF and serum samples were collected at 1, 3 and 12 months after transplantation and analyzed for betaglucan (serum and BALF), neutrophils (BALF) and galactomannan (BALF). Fungal tracheobronchitis was defined according to consensus criteria, modified to include Candida as a mycologic criterion. The cumulative one-year incidence of Candida and Aspergillus tracheobronchitis was 23% and 16%, respectively. Neutrophils of >75% of total leukocytes in BALF had 92% specificity for Candida tracheobronchitis. The area under the ROC curves for betaglucan and galactomannan in BALF to discriminate Aspergillus tracheobronchitis from colonization or no fungal infection were high (0.86 (p < 0.0001) and 0.93 (p < 0.0001), respectively). To conclude, the one-year incidence of fungal tracheobronchitis after lung transplantation was high and dominated by Candida spp. Diagnostic markers in BALF could be useful to discriminate fungal colonization from tracheobronchitis.

Recipient Management before Lung Transplantation

Lung transplantation is considered a viable treatment option for patients with end-stage lung disease. Recent decades have seen a gradual increase in the number of lung transplantation patients worldwide, and in South Korea, the case number has increased at least 3-fold during the last decade. Furthermore, the waiting list time is becoming longer, and more elderly patients (>65 years) are undergoing lung transplantation; that is, the patients placed on the waiting list are older and sicker than in the past. Hence, proper management during the pre-transplantation period, as well as careful selection of candidates, is a key factor for transplant success and patient survival. Although referring and transplant centers should address many issues, the main areas of focus should be the timing of referral, nutrition, pulmonary rehabilitation, critical care (including mechanical ventilation and extracorporeal membrane oxygenation), psychological support, and the management of preexisting comorbid conditions (coronary artery disease, diabetes mellitus, gastroesophageal reflux disease, osteoporosis, malignancy, viral infections, and chronic infections). In this context, the present article reviews and summarizes the pre-transplantation management strategies for adult patients listed for lung transplantation.

Fungal Infections in Lung Transplantation

Purpose of Review

We aim to understand the most common fungal infections associated with the post-lung transplant period, how to diagnose, treat, and prevent them based on the current guidelines published and our center’s experience.

Recent Findings

Different fungi inhabit specific locations. Diagnosis of invasive fungal infections (IFIs) depends on symptoms, radiologic changes, and a positive microbiological or pathology data. There are several molecular tests that have been used for diagnosis. Exposure to fungal prophylaxis can predispose lung transplant recipients to these emerging molds. Understanding and managing medication interactions and drug monitoring are essential in successfully treating IFIs.

Summary

With the increasing rate of lung transplantations being performed, and the challenges posed by the immunosuppressive regimen, understanding the risk and managing the treatment of fungal infections are imperative to the success of a lung transplant recipient. There are many ongoing clinical trials being conducted in hopes of developing novel antifungals.

The importance of CYP2C19 genotype in tacrolimus dose optimization when concomitant with voriconazole in heart transplant recipients

AIMS

Voriconazole remains the mainstay for the treatment of invasive fungal infections in the heart transplant patients and can significantly increase tacrolimus exposure because of drug-drug interaction (DDI). However, the magnitude of this DDI is highly variable and difficult to predict. The purpose of this study was to present the characteristics of DDI between tacrolimus and voriconazole, and further identify the various predictors of tacrolimus dose modification.

METHODS

We retrospectively enrolled 69 heart transplant recipients without using voriconazole as the control and 68 patients received voriconazole treatment in voriconazole group. CYP3A4*1G, CYP3A5*3 and CYP2C19*2 or *3 were thereafter genotyped by Sanger sequencing. The requirement of tacrolimus dose to achieve the therapeutic concentrations and tacrolimus dose-corrected trough concentration (C₀ /D) before and after VRC administration were evaluated.

RESULTS

The DDI between tacrolimus and voriconazole displayed a large inter-individual variability with more than ten-fold changes in tacrolimus dose (range 1.28-13.00) and C₀ /D (range 1.43-13.75). Besides, the fold changes of tacrolimus dose were associated with CYP2C19 genotype, which was found to be significantly lower in CYP2C19 extensive metabolizers than that in CYP2C19 intermediate metabolizers or poor metabolizers (4.06±1.85 vs 5.49±2.47, p=0.0031). However, no significant difference was found in both CYP3A4 and CYP3A5 genotypes. Moreover, CYP2C19 genotype and hematocrit acted as independent predicting factors for tacrolimus dose modification after voriconazole co-therapy.

CONCLUSIONS

The findings of this study have identified the various important factors to adjust tacrolimus dosage when co-administrated with voriconazole in individual patients. CYP2C19 genotype and hematocrit should be considered in tailoring tacrolimus dose.

Safety of Inhaled Amphotericin B Lipid Complex as Antifungal Prophylaxis in Lung Transplant Recipients

Inhaled formulations of amphotericin B are the most widely used antifungal prophylactic agents in lung transplant recipients, yet there are limited data on their safety. We performed a single-center retrospective cohort study of 603 consecutive patients who underwent lung transplantation between 2012 and 2017 and received antifungal prophylaxis with inhaled amphotericin B lipid complex (iABLC) from the day of transplantation until hospital discharge. Of 603 patients, 600 (99.5%) received ≥1 dose of iABLC, and 544 (90.2%) completed the recommended prophylactic course. In total, 4,128 iABLC doses (median, 5; range, 1 to 48 per patient) were administered; 24 patients received >3 months of therapy. Only one (0.2%) patient discontinued therapy due to a drug-attributable adverse event. During the first posttransplant year, 80 (13.3%) patients died (median time to death, 171 days; interquartile range [IQR], 80 to 272 days), and 3,352 (median, 6 per patient) lung biopsies were performed; 414 (68.7%) patients developed biopsy-proven acute cellular rejection. One-year adverse events in our cohort of lung transplant recipients treated with iABLC during transplant hospitalization matched national outcomes for rejection, graft loss, and death. iABLC is a safe and well-tolerated antifungal prophylactic agent in lung transplant recipients.

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.

Inhaled Antifungal Agents for Treatment and Prophylaxis of Bronchopulmonary Invasive Mold Infections

Pulmonary mold infections are life-threatening diseases with high morbi-mortalities. Treatment is based on systemic antifungal agents belonging to the families of polyenes (amphotericin B) and triazoles. Despite this treatment, mortality remains high and the doses of systemic antifungals cannot be increased as they often lead to toxicity. The pulmonary aerosolization of antifungal agents can theoretically increase their concentration at the infectious site, which could improve their efficacy while limiting their systemic exposure and toxicity. However, clinical experience is poor and thus inhaled agent utilization remains unclear in term of indications, drugs, and devices. This comprehensive literature review aims to describe the pharmacokinetic behavior and the efficacy of inhaled antifungal drugs as prophylaxes and curative treatments both in animal models and humans.

Multiresistant organisms: bacteria and beyond

PURPOSE OF REVIEW

Infections with multiresistant organisms are an emerging problem, cause early mortality post lung transplantation and are sometimes associated with graft dysfunction. Frequently they raise questions about the selection of lung transplant candidates and therapeutic management post lung transplantation. There are no guidelines and management must be individualized. This review summarizes the available therapeutic options in cases of multidrug-resistant (MDR) organisms and outcomes after lung transplant.

RECENT FINDINGS

Improvements in diagnosis, new and more effective drugs and the experience gained in the management of these infections in lung transplantation, lead to a more optimistic horizon than that found a decade ago.

SUMMARY

Update on the management of Burkholderia cepacia complex, Mycobacterium abscessus complex, Aspergillus spp., Scedosporium spp. and Lomentospora prolificans infections. This review clarifies current posttransplant outcomes and adds a little hope in these scenarios.

Diagnosis and treatment of cryptococcal osteomyelitis in a pediatric lung transplant patient

BACKGROUND

Asymptomatic pulmonary nodules may appear at any point after lung transplantation. The differential diagnosis is broad and includes serious life-threatening disease entities.

METHODS

A retrospective case report of a single patient who developed a pulmonary nodule after lung transplantation.

RESULTS

At 2 years post-transplant, an 11-year-old with cystic fibrosis was asymptomatic and had normal lung function. A single nodule was noted on surveillance chest CT scan. Initial evaluation was negative, but subsequently, he was diagnosed with cryptococcal osteomyelitis in a thoracic rib. He responded well to an extended course of antifungal therapy without loss of allograft function or infectious complications.

CONCLUSION

Pulmonary nodules after lung transplantation may be a harbinger of serious complications. A systematic approach to evaluation and follow-up is recommended.

Molecular identification of Aspergillus fumigatus complex from lung transplant recipients using multilocus sequencing analysis (MLSA)

BACKGROUND

Aspergillus infection causes significant morbidity and mortality among lung transplant recipients (LTRs). It is primarily caused by Aspergillus fumigatus. Other closely related species belonging to the section Fumigati have also been found. These cryptic species are often misidentified as A. fumigatus. Thus, we used multilocus sequencing analysis (MLSA) of the calmodulin, β-tubulin, and hydrophobin gene sequences to identify these species and to determine the frequency with which they occur among LTRs.

METHODS

A total of 81 A. fumigatus isolates were initially isolated from bronchoalveolar lavage fluid or sputum specimens collected from lung transplant patients. These isolates were then sub-cultured and genotyped using MLSA. Of these isolates, 53, 17, and 11 were isolated from double LTRs, single LTRs, and pre-LTRs, respectively.

RESULTS

All isolates (100%) carried DNA sequences identical to those of A. fumigatus reference strains and thus clustered in the same clade with A. fumigatus. Analysis of the MLSA data revealed that A. fumigatus species were the only species recovered in this population of LTRs. The MLSA results were consistent with those routinely obtained by conventional mycological procedures in the microbiology laboratory.

CONCLUSIONS

A. fumigatus appears to be the primary causative agent of colonization or invasive aspergillosis among LTRs. No cryptic species were identified.

Antifungal Drugs TDM: Trends and Update

PURPOSE

The increasing burden of invasive fungal infections results in growing challenges to antifungal (AF) therapeutic drug monitoring (TDM). This review aims to provide an overview of recent advances in AF TDM.

METHODS

We conducted a PubMed search for articles during 2016-2020 using "TDM" or "pharmacokinetics" or "drug-drug-interaction" with "antifungal," consolidated for each AF. Selection was limited to English language articles with human data on drug exposure.

RESULTS

More than 1000 articles matched the search terms. We selected 566 publications. The latest findings tend to confirm previous observations in real-life clinical settings. The pharmacokinetic variability related to special populations is not specific but must be considered. AF benefit-to-risk ratio, drug-drug interaction (DDI) profiles, and minimal inhibitory concentrations for pathogens must be known to manage at-risk situations and patients. Itraconazole has replaced ketoconazole in healthy volunteers DDI studies. Physiologically based pharmacokinetic modeling is widely used to assess metabolic azole DDI. AF prophylactic use was studied more for Aspergillus spp. and Mucorales in oncohematology and solid organ transplantation than for Candida (already studied). Emergence of central nervous system infection and severe infections in immunocompetent individuals both merit special attention. TDM is more challenging for azoles than amphotericin B and echinocandins. Fewer TDM requirements exist for fluconazole and isavuconazole (ISZ); however, ISZ is frequently used in clinical situations in which TDM is recommended. Voriconazole remains the most challenging of the AF, with toxicity limiting high-dose treatments. Moreover, alternative treatments (posaconazole tablets, ISZ) are now available.

CONCLUSIONS

TDM seems to be crucial for curative and/or long-term maintenance treatment in highly variable patients. TDM poses fewer cost issues than the drugs themselves or subsequent treatment issues. The integration of clinical pharmacology into multidisciplinary management is now increasingly seen as a part of patient care.

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.

Postoperative Management of Lung Transplant Recipients in the Intensive Care Unit

The number of lung transplantations is progressively increasing worldwide, providing new challenges to interprofessional teams and the intensive care units. The outcome of lung transplantation recipients is critically affected by a complex interplay of particular pathophysiologic conditions and risk factors, knowledge of which is fundamental to appropriately manage these patients during the early postoperative course. As high-grade evidence-based guidelines are not available, the authors aimed to provide an updated review of the postoperative management of lung transplantation recipients in the intensive care unit, which addresses six main areas: (1) management of mechanical ventilation, (2) fluid and hemodynamic management, (3) immunosuppressive therapies, (4) prevention and management of neurologic complications, (5) antimicrobial therapy, and (6) management of nutritional support and abdominal complications. The integrated care provided by a dedicated multidisciplinary team is key to optimize the complex postoperative management of lung transplantation recipients in the intensive care unit.

Antifungal Prophylaxis After Lung Transplantation: Where Are We Now?

BACKGROUND

Lung transplantation is an important treatment option for various end-stage lung diseases. However, survival remains limited due to graft rejection and infections. Despite that fungal infections are frequent and carry a bad prognosis, there is currently no consensus on efficacy, optimal drug, route, or duration of antifungal prophylaxis. This narrative review summarizes current strategies for antifungal prophylaxis after lung transplantation.

METHODS

English language articles in Embase, Pubmed, UptoDate, and bibliographies were used to assess the efficacy and safety of available antifungal agents for prophylaxis in adult lung transplant recipients.

RESULTS

Overall, there are limited high-quality data. Universal prophylaxis is more widely used and may be preferable over targeted prophylaxis. Both formulations of inhaled amphotericin B and systemic azoles are effective at reducing fungal infection rates, yet with their own specific advantages and disadvantages. The benefit of combination regimens has yet to be proven. Considering the post-transplant timing of the onset of fungal infections, postoperative prophylaxis during the first postoperative months seems indicated for most patients.

CONCLUSIONS

Based on existing literature, universal antifungal prophylaxis with inhaled amphotericin B and systemic voriconazole for at least 3-6 mo after lung transplantation may be advisable, with a slight preference for amphotericin B because of its better safety profile.

Neutrophile-to-Lymphocyte Ratio as a Predictor of Mortality and Response to Treatment in Invasive Aspergillosis among Heart Transplant Recipients—Exploratory Study

Background and objective: Aspergillus pulmonary infections are potentially life-threatening complications that can occur after heart transplantation. The aim of the study was to find an easily available mortality predictor during Aspergillosis infection therapy following heart transplantation. Materials and methods: This study involved 15 heart recipients with the mean age of 55 ± 6 years who were diagnosed with invasive aspergillosis (IA) in a mean time of 80 ± 53 (19–209) days after orthotropic heart transplantation. Results: Out of fifteen patients diagnosed with IA, five died. The mean time from diagnosis to death in the deceased group was 28 ± 18 days. They were diagnosed with IA in a mean time of 80 ± 53 (19–209) days after orthotropic heart transplantation. During the initial seven days of therapy, the neutrophil to lymphocyte ratio (NLR) significantly differed between the two groups on day three and day seven, with median values of 10.8 [4.3–17.0] vs. 20.2 [17.4–116.8] (p = 0.0373) and 5.2 [3.2–8.1] vs. 32.2 [13.5–49.9] (p = 0.0101) in the survivor and the deceased group, respectively. The NLR was a significant predictor of death both on day three (cut-off point 17.2) and day seven (cut-off point 12.08) of therapy. Conclusions: Findings in our study indicate that NLR may be of predictive value in the estimation of mortality risk or response to treatment among patients with invasive aspergillosis following heart transplantation.