The incidence of invasive aspergillosis among solid organ transplant recipients and implications for prophylaxis in lung transplants

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.

Effect of Mycetoma in Lung Transplant Patients - a Single Center Experience

BACKGROUND

Mycetomas are uncommon in lung transplant recipients. Prior studies have shown increased mortality associated with mycetoma in lung transplant recipients (LTR). We reviewed our center's experience in outcome of LTRs with pre -or post-transplant mycetoma.

METHODS

We retrospectively reviewed electronic health records of LTRs performed at our institute between January 1, 2013 to December 31, 2020.

RESULTS

Mycetoma was present in less than 1 percent of LTR patients (7/1086). Mean age at the time of the transplant was 65 years. Idiopathic pulmonary fibrosis (5/7), interstitial lung disease (1/7), and sarcoidosis (1/7) were underlying pulmonary diagnoses. Seventy-one percent (5/7) received single lung transplant and 29% received double lung transplant. Seventy-one percent had negative serum galactomannan vs 29% (2/7) of patients who had positive serum galactomannan (one post and one pre). Fifty-seven percent had positive bronchoalveolar aspergillus galactomannan (23% had negative). A total of 42% (3/7) were found to have mycetoma before transplant and 58% (4/7) had mycetoma post transplant. Chest computed tomography findings in all patients were consistent with mycetoma.

CONCLUSIONS

In our cohort of patients, mycetoma was not found to be the primary cause of death if diagnosed pre transplant. Transplant recipients with mycetoma pre transplant did not develop invasive fungal infection or mycetoma post transplant. Careful evaluation of lung transplant candidates with mycetoma is critical. Further studies are needed to determine optimal duration of antifungal therapy and to determine if surgical resection may be needed to manage post-lung transplant mycetoma.

Invasive pulmonary aspergillosis in the intensive care unit: current challenges and best practices

The prevalence of invasive pulmonary aspergillosis (IPA) is growing in critically ill patients in the intensive care unit (ICU). It is increasingly recognized in immunocompetent hosts and immunocompromised ones. IPA frequently complicates both severe influenza and severe coronavirus disease 2019 (COVID-19) infection. It continues to represent both a diagnostic and therapeutic challenge and can be associated with significant morbidity and mortality. In this narrative review, we describe the epidemiology, risk factors and disease manifestations of IPA. We discuss the latest evidence and current published guidelines for the diagnosis and management of IPA in the context of the critically ill within the ICU. Finally, we review influenza-associated pulmonary aspergillosis (IAPA), COVID-19-associated pulmonary aspergillosis (CAPA) as well as ongoing and future areas of research.

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

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

Stem Cell Treatment for Diabetic Foot Ulcers: A Meta-analysis of Randomized Clinical Trials

GENERAL PURPOSE

To provide information on the efficacy of stem cells in the treatment of diabetic foot ulcers.

TARGET AUDIENCE

This continuing education activity is intended for physicians, physician assistants, nurse practitioners, and nurses with an interest in skin and wound care.

LEARNING OBJECTIVES/OUTCOMES

After participating in this educational activity, the participant will: 1. Explain outcomes from the use of stem cell treatment for diabetic foot ulcers. 2. Identify features in the methodology of randomized controlled trials examining the efficacy of stem cells in the treatment of diabetic foot ulcers.

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.

Invasive Pulmonary Aspergillosis

Invasive pulmonary aspergillosis is growing in incidence, as patients at risk are growing in diversity. Outside the classical context of neutropenia, new risk factors are emerging or newly identified, such as new anticancer drugs, viral pneumonias and hepatic dysfunctions. Clinical signs remain unspecific in these populations and the diagnostic work-up has considerably expanded. Computed tomography is key to assess the pulmonary lesions of aspergillosis, whose various features must be acknowledged. Positron-emission tomography can bring additional information for diagnosis and follow-up. The mycological argument for diagnosis is rarely fully conclusive, as biopsy from a sterile site is challenging in most clinical contexts. In patients with a risk and suggestive radiological findings, probable invasive aspergillosis is diagnosed through blood and bronchoalveolar lavage fluid samples by detecting galactomannan or DNA, or by direct microscopy and culture for the latter. Diagnosis is considered possible with mold infection in lack of mycological criterion. Nevertheless, the therapeutic decision should not be hindered by these research-oriented categories, that have been completed by better adapted ones in specific settings. Survival has been improved over the past decades with the development of relevant antifungals, including lipid formulations of amphotericin B and new azoles. New antifungals, including first-in-class molecules, are awaited.

Successful treatment of invasive tracheobronchial pulmonary aspergillosis with venovenous extracorporeal membrane oxygenation and combined systemic, intratracheal instillation of liposomal amphotericin B: a case report

BACKGROUND

Invasive pulmonary Aspergillus and invasive bronchial aspergillosis is a life-threatening opportunistic fungal infection that predominantly affects immunocompromised hosts. A case series and review found that the mortality rate of invasive bronchial aspergillosis is high, at about 40%, and 23.7% of invasive bronchial aspergillosis patients require mechanical ventilator management. There are few reports of life-saving cases with venovenous extracorporeal membrane oxygenation as rescue therapy in invasive pulmonary Aspergillus and invasive bronchial aspergillosis. Here, we report a case of invasive bronchial aspergillosis and invasive pulmonary Aspergillus that was successfully treated with venovenous extracorporeal membrane oxygenation, and combined systemic and intratracheal instillation of liposomal amphotericin B.

CASE PRESENTATION

We present the case of a 61-year-old Japanese man with invasive tracheobronchial-pulmonary aspergillosis while receiving chemotherapy for malignant lymphoma. Bronchoscopy revealed trachea covered with pseudomembranous necrotizing tissue, the culture revealed Aspergillus fumigatus, and the histological findings of pseudomembranous revealed fungal hyphae. The patient required venovenous extracorporeal membrane oxygenation because of respiratory failure for atelectasis and obstructive pneumoniae. While continuing systemic administration of liposomal amphotericin B, intratracheal instillation liposomal amphotericin B was performed by bronchoscopy three times a week. Although the respiratory conditions improved and the patient was discontinued on venovenous extracorporeal membrane oxygenation, he ultimately died of recurrence of malignant lymphoma.

CONCLUSION

Intratracheal instillation of liposomal amphotericin B is safe, and liposomal amphotericin B instillation allowed a targeted high local drug concentration, which led to improvement in the invasive bronchial aspergillosis. In addition, since the patient was supported with venovenous extracorporeal membrane oxygenation, we were able to perform safe bronchoscopic debridement of airway lesions and intratracheal instillation of liposomal amphotericin B.

Fungal infection and colonization in lung transplant recipients with chronic lung allograft dysfunction

BACKGROUND

The incidence and impact of de novo fungal airway colonization and infection in lung transplant recipients (LTRs) with known chronic lung allograft dysfunction (CLAD) has not been established. We aimed to determine the 1-year cumulative incidence and risk factors of de novo fungal colonization or infection in LTRs with CLAD and assess the impact of colonization or infection on post-CLAD survival.

METHODS

Prospectively collected Toronto Lung Transplant Program database and chart review were used for double-LTRs who were diagnosed with CLAD from January 1, 2016 to January 1, 2020 and who were free of airway fungi within 1 year prior to CLAD onset. International Society for Heart and Lung Transplantation definitions were used to define clinical syndromes. Cox-Proportional Hazards Models were used for risk-factor analysis. Survival analysis could not be completed secondary to low number of fungal events; therefore, descriptive statistics were employed for survival outcomes.

RESULTS

We found 186 LTRs diagnosed with CLAD meeting our inclusion criteria. The 1-year cumulative incidence for any fungal event was 11.8% (7.0% for infection and 4.8% for colonization). Aspergillus fumigatus was a causative pathogen in eight of 13 (61.5%) patients with infection and six of nine (66.7%) patients with colonization. No patients with fungal colonization post-CLAD developed fungal infection. Peri-CLAD diagnosis (3 months prior or 1 month after) methylprednisolone bolus (hazards ratio: 8.84, p = .001) increased the risk of fungal events. Most patients diagnosed with fungal infections (53.8%) died within 1-year of CLAD onset.

CONCLUSION

De novo IFIs and fungal colonization following CLAD onset were not common. Fungal colonization did not lead to fungal infection. Methylprednisolone bolus was a significant risk factors for post-CLAD fungal events.

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.

Circulating microRNA sequencing revealed miRNome patterns in hematology and oncology patients aiding the prognosis of invasive aspergillosis

Invasive aspergillosis (IA) may occur as a serious complication of hematological malignancy. Delays in antifungal therapy can lead to an invasive disease resulting in high mortality. Currently, there are no well-established blood circulating microRNA biomarkers or laboratory tests which can be used to diagnose IA. Therefore, we aimed to define dysregulated miRNAs in hematology and oncology (HO) patients to identify biomarkers predisposing disease. We performed an in-depth analysis of high-throughput small transcriptome sequencing data obtained from the whole blood samples of our study cohort of 50 participants including 26 high-risk HO patients and 24 controls. By integrating in silico bioinformatic analyses of small noncoding RNA data, 57 miRNAs exhibiting significant expression differences (P < 0.05) were identified between IA-infected patients and non-IA HO patients. Among these, we found 36 differentially expressed miRNAs (DEMs) irrespective of HO malignancy. Of the top ranked DEMs, we found 14 significantly deregulated miRNAs, whose expression levels were successfully quantified by qRT-PCR. MiRNA target prediction revealed the involvement of IA related miRNAs in the biological pathways of tumorigenesis, the cell cycle, the immune response, cell differentiation and apoptosis.

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.

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.

Emerging Fungal Infections: New Species, New Names, and Antifungal Resistance

BACKGROUND

Infections caused by fungi can be important causes of morbidity and mortality in certain patient populations, including those who are highly immunocompromised or critically ill. Invasive mycoses can be caused by well-known species, as well as emerging pathogens, including those that are resistant to clinically available antifungals.

CONTENT

This review highlights emerging fungal infections, including newly described species, such as Candida auris, and those that having undergone taxonomic classification and were previously known by other names, including Blastomyces and Emergomyces species, members of the Rasamsonia argillacea species complex, Sporothrix brasiliensis, and Trichophyton indotinae. Antifungal resistance also is highlighted in several of these emerging species, as well as in the well-known opportunistic pathogen Aspergillus fumigatus. Finally, the increased recognition and importance of fungal co-infections with respiratory pathogens, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is discussed.

SUMMARY

Both clinicians and clinical microbiology laboratories should remain vigilant regarding emerging fungal infections. These may be difficult both to diagnose and treat due to the lack of experience of clinicians and laboratory personnel with these organisms and the infections they may cause. Many of these fungal infections have been associated with poor clinical outcomes, either due to inappropriate therapy or the development of antifungal resistance.

Consensus guidelines for optimising antifungal drug delivery and monitoring to avoid toxicity and improve outcomes in patients with haematological malignancy and haemopoietic stem cell transplant recipients, 2021

Antifungal agents can have complex dosing and the potential for drug interaction, both of which can lead to subtherapeutic antifungal drug concentrations and poorer clinical outcomes for patients with haematological malignancy and haemopoietic stem cell transplant recipients. Antifungal agents can also be associated with significant toxicities when drug concentrations are too high. Suboptimal dosing can be minimised by clinical assessment, laboratory monitoring, avoidance of interacting drugs, and dose modification. Therapeutic drug monitoring (TDM) plays an increasingly important role in antifungal therapy, particularly for antifungal agents that have an established exposure-response relationship with either a narrow therapeutic window, large dose-exposure variability, cytochrome P450 gene polymorphism affecting drug metabolism, the presence of antifungal drug interactions or unexpected toxicity, and/or concerns for non-compliance or inadequate absorption of oral antifungals. These guidelines provide recommendations on antifungal drug monitoring and TDM-guided dosing adjustment for selected antifungal agents, and include suggested resources for identifying and analysing antifungal drug interactions. Recommended competencies for optimal interpretation of antifungal TDM and dose recommendations are also provided.

The Impact of Antifungal Prophylaxis in Lung Transplant Recipients

Rationale: Many lung transplant centers prescribe antifungal medications after transplantation to prevent invasive fungal infections (IFIs); however, the effectiveness of antifungal prophylaxis at reducing the risk of all-cause mortality or IFI has not been established.Objectives: We aimed to evaluate the effect of antifungal prophylaxis on all-cause mortality and IFI in lung transplant patients.Methods: Using administrative claims data, we identified adult patients who underwent lung transplantation between January 1, 2005, and December 31, 2018. Propensity score analysis using inverse probability treatment-weighting approach was used to balance the differences in baseline characteristics between those receiving antifungal prophylaxis and those not receiving antifungal prophylaxis. Cox proportional hazards regression was used to compare rates of all-cause mortality and IFI in both groups.Results: We identified 662 lung transplant recipients (LTRs) (387 received prophylaxis and 275 did not). All-cause mortality was significantly lower in those receiving antifungal prophylaxis compared with those not receiving antifungal prophylaxis (event rate per 100 person-years, 8.36 vs. 19.49; hazard ratio, 0.43; 95% confidence interval, 0.26-0.71; P = 0.003). Patients receiving antifungal prophylaxis had a lower rate of IFI compared with those not receiving prophylaxis (event rate per 100 person-years, 14.94 vs. 22.37; hazard ratio, 0.68; 95% confidence interval, 0.44-1.05; P = 0.079), but did not reach statistical significance.Conclusions: In this real-world analysis, antifungal prophylaxis in LTRs was associated with reduced all-cause mortality compared with those not receiving antifungal prophylaxis. Rates of IFI were also lower in those receiving prophylaxis, but this was not statistically significant in our primary analysis.

Invasive Fungal Sinusitis in Post COVID-19 Patients: A New Clinical Entity

Objectives

Occurrence of invasive fungal respiratory superinfections in patients with COVID‐19 has gained increasing attention in the latest studies. Yet, description of acute invasive fungal sinusitis with its management in those patients is still scarce. This study aims to describe this recently increasing clinical entity in relation to COVID‐19 patients.

Study Design

Longitudinal prospective study.

Methods

Prospective longitudinal study included patients diagnosed with acute invasive fungal rhinosinusitis after a recent COVID‐19 infection. Antifungal agents given included amphotericin B, voriconazole, and/or posaconazole. Surgical treatment was restricted to patients with PCR negative results for COVID‐19. Endoscopic, open, and combined approaches were utilized to eradicate infection. Follow‐up for survived patients was maintained regularly for the first postoperative month.

Results

A total of 36 patients with a mean age of 52.92 ± 11.30 years old were included. Most common associated disease was diabetes mellitus (27.8%). Mycological analysis revealed infection with Mucor and Aspergillus species in 77.8% and 30.6% of patients, respectively. Sino‐nasal, orbital, cerebral, and palatine involvement was found in 100%, 80.6%, 27.8%, and 33.3% of patients, respectively. The most common reported symptoms and signs are facial pain (75%), facial numbness (66.7%), ophthalmoplegia, and visual loss (63.9%). All patients were treated simultaneously by surgical debridement with antifungal medications except for two patients with PCR‐positive swab for COVID‐19. These two patients received antifungal therapy alone. Overall survival rate was 63.89% (23/36).

Conclusion

Clinical suspicion of acute invasive fungal sinusitis among COVID‐19 patients and early management with antifungal therapy and surgical debridement is essential for better outcomes and higher survival.

Level of Evidence

4 Laryngoscope, 131:2652–2658, 2021

Late outcome after surgical and topical treatment for Aspergillus mediastinitis after heart transplantation

The 7-year long-term survival after Aspergillus fumigatus mediastinitis after heart transplantation, an uncommonly described condition, is herein reported. A 66-year-old male developed an infection with A. fumigatus covering the entire thoracic cavity with a fungal turf after orthotopic heart transplantation. Repeated surgical removal of infectious and necrotic tissue together with innovative topical treatment using voriconazole and chlorhexidine combined with systemic antifungal treatment, helped in controlling the infection. Definitive wound closure was achieved by standard sternal refixation and latissimus dorsi muscle flap plasty. Survival after A. fumigatus mediastinitis after heart transplantation was achieved with sequential debridement in combination with topical application of antifungal agents.

Strategies for the Prevention of Invasive Fungal Infections after Lung Transplant

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

Same Game, Different Players: Emerging Pathogens of the CF Lung

Incidences of non-tuberculosis mycobacteria (NTM) and Aspergillus fumigatus have increased around the world over the past decade and have become a significant health threat to immunocompromised individuals such as those with cystic fibrosis (CF). CF is characterized by the buildup of mucus in the lungs which become chronically infected by a myriad of pathogens.

The survival rates of individuals with cystic fibrosis (CF) have significantly increased as a result of improved therapies, such as the inclusion of cystic fibrosis transmembrane conductance regulator (CFTR) modulators for some mutations. However, microbial infection of the airways remains a significant clinical problem. The well-known pathogens Pseudomonas aeruginosa and Staphylococcus aureus continue to establish difficult-to-treat infections in the CF lung. However, in recent years, there has been an increased prevalence of both Aspergillus fumigatus (Af) and non-tuberculous mycobacteria (NTM) species isolated from CF patient sputa. The emergence of these pathogens opens an important area of discussion about multikingdom infections, specifically, how interspecies interactions have the potential to shape the course of infection, such as tolerance to host immune defenses and antimicrobial therapies. Their ability to establish themselves in an existing polymicrobial environment suggests to us that microbial interactions play a significant role, and characterizing these mechanisms and understanding their implications will be critical to the future development of better antimicrobial therapies. With this minireview, we hope to inspire conversations about and demonstrate the merit of more research in this area.

Population Pharmacokinetics of Caspofungin among Extracorporeal Membrane Oxygenation Patients during the Postoperative Period of Lung Transplantation

Little is known about the influence of extracorporeal membrane oxygenation (ECMO) on the pharmacokinetics (PK) of caspofungin. The aim of this study was to describe population PK of caspofungin in patients with and without ECMO during the postoperative period of lung transplantation (LTx) and to investigate covariates influencing caspofungin PK. We compared ECMO patients with non-ECMO patients, and patients before and after ECMO weaning as self-controls, to analyzed changes in caspofungin PK. Eight serial blood samples were collected from each patient for PK analysis. The population PK of caspofungin was described using nonlinear mixed-effects modeling. Twelve ECMO and 7 non-ECMO lung transplant recipients were enrolled in this study. None of the patients received renal replacement therapy during any part of the study period. The PK of caspofungin was best described by a two-compartment model. There were no significant differences in the PK parameters and concentrations of caspofungin among the ECMO, non-ECMO, and self-control group. In the final covariate model, we found that there was a significant association between the male gender and increased distribution volume, that a higher sequential organ failure assessment score was related to an increase in intercompartmental clearance, and that a longer operative time was related to an increase in clearance and the volume of distribution. ECMO did not have a significant impact on the PK of caspofungin in patients after LTx. Some factors were identified as statistically significant covariates related to the PK of caspofungin; however, their impact on clinical practice of caspofungin needs to be investigated further in more studies. (This study has been registered at ClinicalTrials.gov under identifier NCT03766282.).

Antifungal prophylaxis in lung transplant recipients: A systematic review and meta-analysis

BACKGROUND

No consensus exists regarding optimal strategy for antifungal prophylaxis following lung transplant.

OBJECTIVE

To review data regarding antifungal prophylaxis on the development of fungal infections.

STUDY SELECTION/APPRAISAL

We searched MEDLINE, Embase, and Scopus for eligible articles through December 10, 2019. Observational or controlled trials published after January 1, 2001, that pertained to the prevention of fungal infections in adult lung recipients were reviewed independently by two reviewers for inclusion.

METHODS

Of 1702 articles screened, 24 were included. Data were pooled using random effects model to evaluate for the primary outcome of fungal infection. Studies were stratified by prophylactic strategy, medication, and duration (short term < 6 months and long term ≥ 6 months).

RESULTS

We found no difference in the odds of fungal infection with universal prophylaxis (49/101) compared to no prophylaxis (36/93) (OR 0.76, CI: 0.03-17.98; I2  = 93%) and preemptive therapy (25/195) compared to universal prophylaxis (35/222) (OR 0.91, CI: 0.06-13.80; I2  = 93%). The cumulative incidence of fungal infections within 12 months was not different with nebulized amphotericin (0.08, CI: 0.04-0.13; I2  = 87%) compared to systemic triazoles (0.07, CI: 0.03-0.11; I2  = 21%) (P = .65). Likewise, duration of prophylaxis did not impact the incidence of fungal infections (short term: 0.11, CI: 0.05-0.17; I2  = 89%; long term: 0.06, CI: 0.03-0.08; I2  = 51%; P = .39).

CONCLUSIONS

We have insufficient evidence to support or exclude a benefit of antifungal prophylaxis.

Voriconazole therapeutic drug monitoring in critically ill patients improves efficacy and safety of antifungal therapy

Since voriconazole plasma trough concentration (VPC) is related to its efficacy and adverse events, therapeutic drug monitoring (TDM) is recommended to perform. However, there is no report about the data of voriconazole TDM in critically ill patients in China. This retrospective study was performed to determine whether voriconazole TDM was associated with treatment response and/or voriconazole adverse events in critically ill patients, and to identify the potential risk factors associated with VPC. A total of 216 critically ill patients were included. Patients were divided into two groups: those underwent voriconazole TDM (TDM group, n = 125) or did not undergo TDM (non-TDM group, n = 91). The clinical response and adverse events were recorded and compared. Furthermore, in TDM group, multivariate logistic regression analysis was performed to identify the possible risk factors resulting in the variability in initial VPC. The complete response in the TDM group was significantly higher than that in the non-TDM group (P = .012). The incidence of adverse events strongly associated with voriconazole in the non-TDM group was significantly higher than that in the TDM group (19.8% vs 9.6%; P = .033). The factors, including age (OR 0.934, 95% CI: 0.906-0.964), male (OR 5.929, 95% CI: 1.524-23.062), serum albumin level (OR 1.122, 95% CI: 1.020-1.234), diarrhoea (OR 4.953, 95% CI: 1.495-16.411) and non-intravenous administration (OR 4.763, 95% CI: 1.576-14.39), exerted the greatest effects on subtherapeutic VPC (VPC < 1.5 mg/L) in multivariate analysis. Intravenous administration (OR 7.657, 95% CI: 1.957-29.968) was a significant predictor of supratherapeutic VPC (VPC > 4.0 mg/L). TDM can result in a favourable clinical efficacy and a lower incidence of adverse events strongly associated with voriconazole in critically ill patients. Subtherapeutic VPC was closely related to younger age, male, hyperalbuminaemia, diarrhoea and non-intravenous administration, and intravenous administration was a significant predictor of supratherapeutic VPC.

Epidemiology and Outcomes of Hospitalizations With Invasive Aspergillosis in the United States, 2009-2013

Background

Though invasive aspergillosis (IA) complicates care of up to 13% of patients with immunocompromise, little is known about its morbidity and mortality burden in the United States.

Methods

We analyzed the Health Care Utilization Project's data from the Agency for Healthcare Research and Quality for 2009-2013. Among subjects with high-risk conditions for IA, IA was identified via International Classification of Diseases, Ninth Revision, Clinical Modification codes 117.3, 117.9, and 484.6. We compared characteristics and outcomes between those with (IA) and without IA (non-IA). Using propensity score matching, we calculated the IA-associated excess mortality and 30-day readmission rates, length of stay, and costs.

Results

Of the 66634683 discharged patients meeting study inclusion criteria, 154888 (0.2%) had a diagnosis of IA. The most common high-risk conditions were major surgery (50.1%) in the non-IA and critical illness (41.0%) in the IA group. After propensity score matching, both mortality (odds ratio, 1.43; 95% confidence interval, 1.36-1.51) and 30-day readmission (1.39; 1.34-1.45) rates were higher in the IA group. IA was associated with 6.0 (95% confidence interval, 5.7-6.4) excess days in the hospital and $15542 ($13869-$17215) in excess costs per hospitalization.

Conclusions

Although rare even among high-risk groups, IA is associated with increased hospital mortality and 30-day readmission rates, excess duration of hospitalization, and costs. Given nearly 40000 annual admissions for IA in the United States, the aggregate IA-attributable excess costs may reach $600 million annually.

Efficacy and safety of combination antifungal therapy in Korean haematological patients with invasive aspergillosis

This randomised, double‐blind, placebo‐controlled trial assessed the efficacy, safety and tolerability of voriconazole+anidulafungin (combination) or voriconazole+placebo (monotherapy) for invasive aspergillosis (IA; NCT00531479). We present a post hoc analysis of Korean and non‐Korean patients with IA (including baseline positive serum galactomannan [GM]). Immunocompromised patients ≥ 16 years with IA were randomised 1:1, combination or monotherapy, for ≥ 2 weeks’ treatment. The primary endpoint was 6‐ and 12‐week all‐cause mortality (Korean modified intent‐to‐treat [mITT] population). Overall, 454 patients enrolled (Koreans: 56 [combination: 28, monotherapy: 28], non‐Koreans: 398 [combination: 200, monotherapy: 198]). The mITT population comprised 40 Koreans (combination: 23; monotherapy: 17) and 237 non‐Koreans (combination: 112; monotherapy: 125). Week 6 treatment difference in mortality rate between combination and monotherapy was −6.4% in non‐Koreans. This reduction was more marked in Koreans (−22.4%). Week 12 difference in all‐cause mortality between combination and monotherapy was −17.7% (Koreans) and −20.2% at Week 6 (Koreans; positive baseline GM). Week 6 mortality (Koreans [mITT]; baseline GM >0.5‐2.0) was 0/13 (combination) and 2/6 (monotherapy). Serious adverse events were numerically higher for combination than monotherapy (Koreans: 57.1%, 46.4%; non‐Koreans: 49.5%, 46.0%). In Koreans, combination therapy was associated with marginally better outcomes than monotherapy and more so than in non‐Koreans.

Invasive Aspergillosis in solid-organ transplant recipients: Guidelines from the American Society of Transplantation Infectious Diseases Community of Practice

These updated AST-IDCOP guidelines provide information on epidemiology, diagnosis, and management of Aspergillus after organ transplantation. Aspergillus is the most common invasive mold infection in solid-organ transplant (SOT) recipients, and it is the most common invasive fungal infection among lung transplant recipients. Time from transplant to diagnosis of invasive aspergillosis (IA) is variable, but most cases present within the first year post-transplant, with shortest time to onset among liver and heart transplant recipients. The overall 12-week mortality of IA in SOT exceeds 20%; prognosis is worse among those with central nervous system involvement or disseminated disease. Bronchoalveolar lavage galactomannan is preferred for the diagnosis of IA in lung and non-lung transplant recipients, in combination with other diagnostic modalities (eg, chest CT scan, culture). Voriconazole remains the drug of choice to treat IA, with isavuconazole and lipid formulations of amphotericin B regarded as alternative agents. The role of combination antifungals for primary therapy of IA remains controversial. Either universal prophylaxis or preemptive therapy is recommended in lung transplant recipients, whereas targeted prophylaxis is favored in liver and heart transplant recipients. In these guidelines, we also discuss newer antifungals and diagnostic tests, antifungal susceptibility testing, and special patient populations.

Epidemiology of invasive fungal infections in lung transplant recipients in Western Australia

BACKGROUND

Invasive fungal infections (IFI) are common after lung transplantation with reported incidence of 8.1% to 16% at 12 months post-transplant, and 3-month all-cause mortality after IFI of 21.7%.

METHODS

We performed a retrospective study of IFI and fungal colonization in lung transplants (LTs) from November 2004 to February 2017.

RESULTS

137 LTs were followed for a median 4.1 years (IQR 2.1-6.2 years). In addition to nebulized amphotericin for the transplant admission to all LTs, systemic mold-active azole was given to 80/130 (61.5%) LTs in the first 6 months post-transplant, 57/121 (47.1%) in the period 6-12 months after transplant, and 93/124 (75%) in the period more than 12 months post-transplant. Mold airways colonization was found in 81 (59.1%) LTs before and 110 (80.3%) LTs after transplantation. There were 13 IFIs for an overall incidence of 2.1 per 100 person-years, occurring at a median 583 days (IQR 182-1110 days) post-transplant, a cumulative incidence of 3.8% at 1 year, 7.6% at 3 years and 10.1% at 5 years post-transplant. All-cause 3-month mortality after IFI was 7.7%. Aspergillus species followed by Scedosporium apiospermum and Cryptococcus species were the commonest fungi causing IFI.

CONCLUSIONS

In our cohort the rate of IFI was comparatively low, likely because of comprehensive early antifungal use and preemptive therapy at any time after transplant. Prospective studies of fungal colonization late after LT are required to determine the risks and benefits of watchful waiting compared to preemptive therapy.

Why do lung transplant patients discontinue triazole prophylaxis?

BACKGROUND

Lung transplant recipients are prone to invasive fungal infections prompting many transplant centers to use prolonged triazole antifungal prophylaxis. From a practical standpoint, it is unclear if lung transplant recipients are able to continue prolonged or lifelong prophylaxis without premature discontinuation from side effects, drug interactions, development of fungal disease, or medication cost. We examined the number of patients that are able to reach a prophylactic endpoint and understand the reasons for early termination.

METHODS

We conducted a retrospective chart review of all lung and heart-lung transplant patients at Mayo Clinic Rochester from May 1, 2002 to December 31, 2017. Type, duration, and reason for discontinuation of triazole prophylaxis were examined.

RESULTS

During the study period, 193 patients underwent lung or heart-lung transplantation. Itraconazole, voriconazole, and posaconazole were given to 180, 73, and 60 post-transplant patients, respectively. Providers switched itraconazole to another prophylactic antifungal medication for reasons other than prophylactic completion in 61.8% (126 out of 204) of exposure episodes; this was similar with voriconazole (68.8%, 53 out of 77, P = 0.41). Posaconazole was actively discontinued significantly less often (18.3%, 11 out of 60, P < 0.05). The most common reasons for discontinuing itraconazole were malabsorption (15.5% of exposure episodes) and concern for breakthrough fungal infection (10.2%). In comparison, the most common reason for voriconazole discontinuation was side effect or intolerance (54.5% of VR exposure episodes vs 9.8% of IT exposure episodes, P < 0.05).

CONCLUSIONS

Itraconazole and posaconazole appeared to have fewer side effects prompting discontinuation than voriconazole, but itraconazole was discontinued more often because of malabsorption and clinical suspicion of fungal infections.

Infections in Heart, Lung, and Heart-Lung Transplantation

Half a century has passed since the first orthotopic heart transplant took place. Surgical innovations allowed for heart, lung, and heart-lung transplantation to save lives of patients with incurable chronic cardiopulmonary conditions. The complexity of the surgical interventions, chronic host health conditions, and antirejection immunosuppressive medications makes infectious complications common. Infections have remained one of the main barriers for successful transplantation and a source of significant morbidity and mortality. Recognition of infections and its management in this setting require outstanding clinical skills since transplant recipients may not exhibit classic signs or symptoms of disease, and laboratory work has some pitfalls. The prevention, identification, and management of infectious diseases complications in this population are a priority to undertake to improve the medical outcomes of transplantation. Herein, we reviewed the historical aspects, epidemiology, and prophylaxis of infections in heart, lung, and heart-lung transplantation. We also discuss the most prevalent organisms affecting the host and the organ systems involved.

Two New Fluorinated Phenol Derivatives Pyridine Schiff Bases: Synthesis, Spectral, Theoretical Characterization, Inclusion in Epichlorohydrin-β-Cyclodextrin Polymer, and Antifungal Effect

It has been reported that the structure of the Schiff bases is fundamental for their function in biomedical applications. Pyridine Schiff bases are characterized by the presence of a pyridine and a phenolic ring, connected by an azomethine group. In this case, the nitrogen present in the pyridine is responsible for antifungal effects, where the phenolic ring may be also participating in this bioactivity. In this study, we synthesized two new pyridine Schiff Bases: (E)-2-[(3-Amino-pyridin-4-ylimino)-methyl]-4,6-difluoro-phenol (F1) and (E)- 2-[(3-Amino-pyridin-4-ylimino)-methyl]-6-fluoro-phenol (F2), which only differ in the fluorine substitutions in the phenolic ring. We fully characterized both F1 and F2 by FTIR, UV-vis, ¹H; ¹³C; ¹⁹F-NMR, DEPT, HHCOSY, TOCSY, and cyclic voltammetry, as well as by computational studies (DFT), and NBO analysis. In addition, we assessed the antifungal activity of both F1 (two fluorine substitution at positions 4 and 6 in the phenolic ring) and F2 (one fluorine substitution at position 6 in the phenolic ring) against yeasts. We found that only F1 exerted a clear antifungal activity, showing that, for these kind of Schiff bases, the phenolic ring substitutions can modulate biological properties. In addition, we included F1 and F2 into in epichlorohydrin-β-cyclodextrin polymer (βCD), where the Schiff bases remained inside the βCD as determined by the k_i, TGA, DSC, and S_BET. We found that the inclusion in βCD improved the solubility in aqueous media and the antifungal activity of both F1 and F2, revealing antimicrobial effects normally hidden by the presence of common solvents (e.g., DMSO) with some cellular inhibitory activity. The study of structural prerequisites for antimicrobial activity, and the inclusion in polymers to improve solubility, is important for the design of new drugs.

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

BACKGROUND

There is lack of recent multicenter epidemiological data on invasive aspergillosis (IA) among solid organ transplant recipient (SOTr) in the mold-acting antifungal era. We describe the epidemiology and outcomes of IA in a contemporary cohort of SOTr using the Swiss Transplant Cohort Study.

METHODS

All consecutive SOTr with proven or probable IA between 01.05.2008 and 31.12.2014 were included. A case-control study to identify IA predictors was performed: 1-case was matched with 3-controls based on SOT type, transplant center, and time post-SOT.

RESULTS

Among 2868 SOTr, 70 (2.4%) patients were diagnosed with proven (N: 30/70, 42.9%) or probable (N: 40/70, 57.1%) IA. The incidence of IA was 8.3%, 7.1%, 2.6%, 1.3%, and 1.2% in lung, heart, combined, kidney, and liver transplant recipients, respectively, Galactomannan immunoassay was positive in 1/3 of patients tested. Only 33/63 (52.4%) of patients presented with typical pulmonary radiographic findings. Predictors of IA included: renal insufficiency, re-operation, and bacterial and viral infections. 12-week mortality was higher in liver (85.7%, 6/7) compared to other (15.9%, 10/63; P < .001) SOTr.

CONCLUSIONS

Invasive aspergillosis remains a rare complication post-SOT, with atypical radiographic presentations and low positivity rates of biomarkers posing significant diagnostic challenges. Although overall mortality has decreased in SOTr, it remains high in liver SOTr.

Respiratory Fungal Infections in Solid Organ and Hematopoietic Stem Cell Transplantation

Respiratory fungal infections are associated with high morbidity and mortality in hematopoietic stem cell (HSCT) and solid organ (SOT) transplant recipients, and are caused primarily by molds. Aspergillus is the most common pathogen. The net state of immunosuppression plays a major role in the risk of respiratory fungal infections after transplantation. Clinical presentation can be atypical and diagnosis can be delayed due to low sensitivity of diagnostic methods or inability to obtain adequate specimens. Fungal infections in HSCT and SOT carry a higher risk of dissemination. New prophylaxis strategies have changed the epidemiology of fungal infections in this patient population.

Risk and outcomes of pulmonary fungal infection after pediatric lung transplantation

BACKGROUND

Prospective studies to determine associated risk factors and related outcomes for pulmonary fungal infection (PFI) after pediatric lung transplant (PLT) are lacking.

METHODS

NIH-sponsored Clinical Trials in Organ Transplantation in Children enrolled PLT candidates, collecting data prospectively for 2 years post-transplant. Demographics, signs/symptoms, radiology, pathology and microbiology were collected. Analyses evaluated for PFI-related risks and outcomes.

RESULTS

In 59 PLT, pre-transplant fungal colonization occurred in 6 donors and 15 recipients. Cystic fibrosis (CF) was associated with pre-transplant colonization (P < .01). Twenty-five (42%) PLT had 26 post-transplant colonizations (median = 67 days, range = 0-750 days) with Candida (13), Aspergillus (4), mold (6) or yeast (3). Post-PLT colonization was not associated with CF, age, or pre-PLT colonization. Thirteen PFIs occurred in 10 (17%) patients, 3 proven (Candida species) and 10 probable (Candida [3], Aspergillus [3], Penicillium [3], and mold [1]). Pulmonary fungal infection was preceded by post-PLT colonization with the same organism in 4 of 13 PFI, but post-PLT colonization did not predict subsequent PFI (P = .87). Older age at transplant was a risk for PFI (P < .01). No mortality was attributed to PFI. Prophylaxis use was not associated with decreased post-PLT colonization (P = .60) or PFI (P = .48).

CONCLUSION

In PLT, PFI and fungal colonization are common but without associated mortality. Post-PLT colonization did not predict PFI. Optimal prevention strategies require additional study.

Infectious diseases in solid organ transplant recipients: Analysis of autopsied cases in Japan

BACKGROUND

With the improvements in immunosuppressive agents and graft survival, infections such as mycoses have become major complications after solid organ transplantation (SOT).

METHODS

Our group has continuously updated an epidemiological database of visceral mycoses (VM) among autopsy cases in Japan since 1989. Data on infectious agents and clinical information were complied using similar procedures.

RESULTS

Among the all autopsied cases studied, 356 undergone SOT. Of these, 214 (60.1%) suffered from one or more types of infections, including 51 (14.3%) with VM. Thus, the incidence of VM was higher in SOT recipients than in non-transplanted cases (P < 0.0001). Aspergillus spp. (Asp) was the most predominant agent and Candida spp. was second. Specifically, among SOT recipients, Asp was the most predominant in liver and lung transplant recipients. Among the 217 autopsied liver transplants cases, the incidence of VM was highest in those with fulminant hepatitis (FH, P = 0.01). The incidence of cytomegalovirus infection tended to be higher in cases with mycosis (P = 0.06). Multivariate logistic regression analysis identified FH (odds ratio, 3.61, 95% confidence interval 1.34-9.75; P = 0.03) as an independent risk factor for mycosis in liver transplant recipients.

CONCLUSION

This epidemiological analysis of autopsied cases provides a strong incentive to intensify efforts to diagnose and treat post-SOT infectious diseases.

Trends in Hospitalizations Related to Invasive Aspergillosis and Mucormycosis in the United States, 2000-2013

BACKGROUND

Invasive aspergillosis (IA) and mucormycosis contribute to substantial mortality, especially among immunocompromised persons, including those with hematopoietic stem cell transplant (HSCT), hematologic malignancy (HM), and solid organ transplant (SOT).

METHODS

Using International Classification of Diseases, Ninth Revision codes available in the National Inpatient Sample, a hospital discharge database, we estimated IA-related hospitalizations (IA-RH), mucormycosis-RH (M-RH), HSCT-RH, HM-RH, and SOT-RH during 2000-2013. United States census data were used to calculate overall M-RH and IA-RH rates and present trends; estimated annual numbers of HSCT-RH, HM-RH, and SOT-RH served as denominators to calculate M-RH and IA-RH rates occurring with these conditions. Weighted least-squares technique was used to test for linear trends and calculate average annual percentage change (APC).

RESULTS

There were an estimated 169 110 IA-RH and 9966 M-RH during 2000-2013. Overall, IA-RH and M-RH rates per million persons rose from 32.8 to 46.0 (APC = +2.9; P < .001) and 1.7 to 3.4 (APC = +5.2%; P < .001), respectively, from 2000 to 2013. Among HSCT-RH, there was no significant change in M-RH rate, but a significant decline occurred in IA-RH rate (APC = -4.6%; P = .004). Among HM-RH, the rate of M-RH increased (APC = +7.0%; P < .001), but the IA-RH rate did not change significantly (APC = +1.2%; P = .073). Among SOT-RH, M-RH (APC = +6.3%; P = .038) and IA-RH rates (APC = +4.1%; P < .001) both increased.

CONCLUSIONS

Overall IA-RH and M-RH rates increased during 2000-2013, with a doubling of M-RH. Mucormycosis-related hospitalization occurring in conjunction with certain comorbidities increased, whereas IA-RH rates among patients with the comorbidities, decreased, remained stable, or increased to a lesser extent than M-RH.

Invasive Fungal Infections in the Critically Ill Patient

Invasive fungal infections have become an increasingly prevalent and disturbing problem in critically ill patients. The advent of broad-spectrum antibacterial therapy and immunosuppressant therapy, among other factors such as mechanical ventilation, places the intensive care patient at significant risk for infection with pathogenic fungi. Most patients who become infected with invasive fungi, especially Candida species, have been previously colonized with the offending organism, lending to the notion that colonization precedes infection inmany cases. Despite an ever-increasing array of antifungal therapy for these infections, mortality rates remain extremely high, especially when the bloodstream is the primary site of infection. In addition, a shift toward more resistant pathogens such asCandida glabrata, Candida krusei, and moldswill provide clinicianswith therapeutic challenges for many years. The wide variation in acquisition cost across antifungal agents adds an additional layer of complexity to clinical decision making. Newer antifungal agents, each with its own advantages and disadvantages, have become available in recent years. Placing each agent in its appropriate niche is a dilemma that has yet to be solved.

Antifungal peptides: To be or not to be membrane active

Most antifungal peptides (AFPs), if not all, have membrane activity, while some also have alternative targets. Fungal membranes share many characteristics with mammalian membranes with only a few differences, such as differences in sphingolipids, phosphatidylinositol (PI) content and the main sterol is ergosterol. Fungal membranes are also more negative and a better target for cationic AFPs. Targeting just the fungal membrane lipids such as phosphatidylinositol and/or ergosterol by AFPs often translates into mammalian cell toxicity. Conversely, a specific AFP target in the fungal pathogen, such as glucosylceramide, mannosyldiinositol phosphorylceramide or a fungal protein target translates into high pathogen selectivity. However, a lower target concentration, absence or change in the specific fungal target can naturally lead to resistance, although such resistance in turn could result in reduced pathogen virulence. The question is then to be or not to be membrane active - what is the best choice for a successful AFP? In this review we deliberate on this question by focusing on the recent advances in our knowledge on how natural AFPs target fungi.