Invasive fungal infections among organ transplant recipients: results of the Transplant-Associated Infection Surveillance Network (TRANSNET)

Case Report: Malacoplakia Due to E. coli With Cryptococcus albidus Infection of a Transplanted Kidney in a Patient With Recurrent Urinary Tract Infection

Background: Colonization of Cryptococcus rarely occurs in a graft. This study reports a case of malacoplakia and cryptococcoma caused by E. coli and Cryptococcus albidus in a transplanted kidney, with detailed pathology and metagenome sequencing analysis.

Case Presentation: We presented a case of cryptococcoma and malacoplakia in the genitourinary system including the transplant kidney, bladder, prostate, and seminal vesicles caused by Cryptococcus albidus and Escherichia coli in a renal-transplant recipient. Metagenome sequencing was conducted on a series of samples obtained from the patient at three different time points, which we termed Phase I (at the diagnosis of cryptococcoma), Phase II (during perioperative period of graftectomy, 3 months after the diagnosis), and Phase III (2 months after graftectomy). Sequencing study in the Phase I detected two and four sequences of C. albidus respectively in cerebrospinal fluid (CSF) and feces, with resistant Escherichia coli 09-02E presented in urine and renal mass. A 3-month antibiotic treatment yielded a smaller bladder lesion but an enlarged allograft lesion, leading to a nephrectomy. In the Phase II, two sequences of C. albidus were detected in CSF, while the E. coli 09-02E continued as before. In the Phase III, the lesions were generally reduced, with one C. albidus sequence in feces only.

Conclusions: The existence and clearance of Cryptococcus sequences in CSF without central nervous system symptoms may be related to the distribution of infection foci in vivo, the microbial load, and the body's immunity. Overall, this study highlights the need for enhanced vigilance against uncommon types of Cryptococcus infections in immunocompromised populations and increased concern about the potential correlation between E. coli and Cryptococcus infections.

Gut Microbiota Modulation as a Potential Target for the Treatment of Lung Infections

The gastrointestinal and respiratory systems are colonized by a complex ecosystem of microorganisms called the microbiota. These microorganisms co-evolved over millions of years with the host, creating a symbiotic relationship that is fundamental for promoting host homeostasis by producing bioactive metabolites and antimicrobial molecules, and regulating the immune and inflammatory responses. Imbalance in the abundance, diversity, and function of the gut microbiota (known as dysbiosis) have been shown to increase host susceptibility to infections in the lungs, suggesting crosstalk between these organs. This crosstalk is now referred to as the gut-lung axis. Hence, the use of probiotics, prebiotics, and synbiotics for modulation of gut microbiota has been studied based on their effectiveness in reducing the duration and severity of respiratory tract infections, mainly owing to their effects on preventing pathogen colonization and modulating the immune system. This review discusses the role and responses of probiotics, prebiotics, and synbiotics in the gut-lung axis in the face of lung infections.

Limited Index of Clinical Suspicion and Underdiagnosis of Histopathologically Documented Invasive Mold Infections

Invasive mold infections (IMIs) are difficult to diagnose. This analysis of histopathologically proven IMIs at our institution (2010-2019) showed that 11/41 (27%) of them were not suspected at the time of biopsy/autopsy (9/17, 53% among autopsies). The rate of missed diagnosis was particularly high (8/16, 50%) among nonhematologic cancer patients.

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

Background

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

Conclusion

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

What Is the Part of Tropical Diseases Among Infectious Complications in Renal Transplant Recipients in the Amazon? A 12-Year Multicenter Retrospective Analysis in French Guiana

BACKGROUND

Infectious complications in kidney transplant recipients (KTRs) are well studied in temperate countries but remain barely known in tropical ones. The main objective of this study was to describe infection-related hospitalizations in patients living in the Amazon, where it has never been described.

METHODS

All KTRs residing in French Guiana between 2007 and 2018 were included retrospectively. Infection-related hospitalizations were collected in the main medical centers of the territory.

RESULTS

Eighty-two patients were included, and 42 were infected during the study period (51%). Eighty-seven infections were identified. The main sites of infection were urinary, in 29% of cases (25/87), and pulmonary, in 22% of cases (19/87). When documented (48/87), bacterial infections were predominant (35/48), followed by viral (8/48), fungal (4/48), and parasitic infections (1/48). Endemic so-called tropical infections accounted for 6% of infections (5/87). Histoplasma capsulatum was the most commonly isolated fungus (2/4).

CONCLUSIONS

This study suggests that the spectrum of infections in KTRs in French Guiana differs little from that of temperate countries. Nevertheless, some tropical infections are described. More studies on fungal infections in KTRs should be undertaken to clarify the weight of histoplasmosis in these patients.

Aspergillus fumigatus and aspergillosis: From basics to clinics

The airborne fungus Aspergillus fumigatus poses a serious health threat to humans by causing numerous invasive infections and a notable mortality in humans, especially in immunocompromised patients. Mould-active azoles are the frontline therapeutics employed to treat aspergillosis. The global emergence of azole-resistant A. fumigatus isolates in clinic and environment, however, notoriously limits the therapeutic options of mould-active antifungals and potentially can be attributed to a mortality rate reaching up to 100 %. Although specific mutations in CYP 51A are the main cause of azole resistance, there is a new wave of azole-resistant isolates with wild-type CYP 51A genotype challenging the efficacy of the current diagnostic tools. Therefore, applications of whole-genome sequencing are increasingly gaining popularity to overcome such challenges. Prominent echinocandin tolerance, as well as liver and kidney toxicity posed by amphotericin B, necessitate a continuous quest for novel antifungal drugs to combat emerging azole-resistant A. fumigatus isolates. Animal models and the tools used for genetic engineering require further refinement to facilitate a better understanding about the resistance mechanisms, virulence, and immune reactions orchestrated against A. fumigatus. This review paper comprehensively discusses the current clinical challenges caused by A. fumigatus and provides insights on how to address them.

Invasive aspergillosis in critically ill patients: Review of definitions and diagnostic approaches

Invasive aspergillosis (IA) is an increasingly recognised phenomenon in critically ill patients in the intensive care unit, including in patients with severe influenza and severe coronavirus disease 2019 (COVID-19) infection. To date, there are no consensus criteria on how to define IA in the ICU population, although several criteria are used, including the AspICU criteria and new consensus criteria to categorise COVID-19-associated pulmonary aspergillosis (CAPA). In this review, we describe the epidemiology of IA in critically ill patients, most common definitions used to define IA in this population, and most common clinical specimens obtained for establishing a mycological diagnosis of IA in the critically ill. We also review the most common diagnostic tests used to diagnose IA in this population, and lastly discuss the most common clinical presentation and imaging findings of IA in the critically ill and discuss areas of further needed investigation.

A Comparative Analysis of Mucormycosis in Immunosuppressed Hosts Including Patients with Uncontrolled Diabetes in the Southwest United States

BACKGROUND

Mucormycosis (zygomycosis) is an invasive fungal infection that carries a high risk of morbidity and mortality. Uncontrolled diabetes mellitus and other immunocompromising conditions are risk factors for mucormycosis development. We here describe the differences in characteristics and outcomes of mucormycosis among solid organ transplant, hematological malignancy, and diabetes mellitus groups at our institution.

METHODS

We conducted a retrospective chart review over the period of 2009-2020, with identifying patients using the International Classification of Diseases, Ninth and Tenth Revisions. Clinical, laboratory, and outcome data were collected.

RESULTS

There were 28 patients identified: 7 solid organ transplant, 3 hematological malignancy, and 18 diabetes mellitus patients were included in the study. Three solid organ transplant patients experienced an episode of rejection, and another 3 had cytomegalovirus infection prior to presenting with mucormycosis. Four of seven solid organ transplant patients had a history of diabetes mellitus, but the median hemoglobin A1C was lower than in the diabetes mellitus group (6.3 vs 11.5; P = .006). The mortality rate difference between solid organ transplant and diabetes mellitus was not statistically significant: 2/7 (28.57%) vs 5/18 (27.78%); P = .66. Patients with bilateral disease (pulmonary or sinus) had significantly higher mortality (80% vs 13%, P = .008). There was no difference in mortality outcomes among the different types of antifungal therapies administered.

CONCLUSION

A multispecialty approach is imperative in mucormycosis therapy. While the underlying risk factors were different, the outcomes were comparable for the solid organ transplant and diabetes mellitus groups. Future larger and longitudinal studies are recommended.

Central nervous system infections after solid organ transplantation

PURPOSE OF REVIEW

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

RECENT FINDINGS

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

SUMMARY

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

Next generation sequencing for diagnosis of central nervous system aspergillosis in liver transplant recipients

Background

Fungal encephalitis is uncommon and sometimes fatal in liver transplant (LT) recipients. Early diagnosis of central nervous system (CNS) fungal infections, especially aspergillosis, is difficult based on routine tests of cerebrospinal fluid (CSF) alone. Next-generation sequencing (NGS) as a new tool may help in this respect.

Methods

Shotgun metagenomics was used to detect pathogens in CSF of patients, who were clinically suspected of CNS infection. Sequencing was performed at BGIseq-50 platform (BGI, Shenzhen).

Results

NGS technique identified Aspergillus in CSF of 5 patients, who were suspected of CNS infection, although clinical symptoms of these patients varied dramatically. The resulting sequence reads corresponding to Aspergillus species ranged from 2 to 25, with genomic coverage ranging from 0.0003% to 0.0036%. Rapid identification of Aspergillus enabled early appropriate antifungal therapy, although 4 patients eventually died of severe infection.

Conclusions

This is the first study to highlight the utility of NGS in early diagnosis of CNS aspergillosis in LT recipients. This new tool may be helpful in improving the diagnosis of CNS aspergillosis.

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.

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

INTRODUCTION

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

The Prediction and Prognosis of Fungal Infection in Lung Transplant Recipients-A Retrospective Cohort Study in South Korea

(1) Background: Lung transplant recipients (LTRs) are at substantial risk of invasive fungal disease (IFD), although no consensus has been reached on the use of antifungal agents (AFAs) after lung transplantation (LTx). This study aimed to assess the risk factors and prognosis of fungal infection after LTx in a single tertiary center in South Korea. (2) Methods: The study population included all patients who underwent LTx between January 2012 and July 2019 at a tertiary hospital. It was a retrospective cohort study. Culture, bronchoscopy, and laboratory findings were reviewed during episodes of infection. (3) Results: Fungus-positive respiratory samples were predominant in the first 90 days and the overall cumulative incidence of Candida spp. was approximately three times higher than that of Aspergillus spp. In the setting of itraconazole administration for 6 months post-LTx, C. glabrata accounted for 36.5% of all Candida-positive respiratory samples. Underlying connective tissue disease-associated interstitial lung disease, use of AFAs before LTx, a longer length of hospital stay after LTx, and old age were associated with developing a fungal infection after LTx. IFD and fungal infection treatment failure significantly increased overall mortality. Host factors, antifungal drug resistance, and misdiagnosis of non-Aspergillus molds could attribute to the breakthrough fungal infections. (4) Conclusions: Careful bronchoscopy, prompt fungus culture, and appropriate use of antifungal therapies are recommended during the first year after LTx.

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Emerging fungal pathogens in solid organ transplantation

PURPOSE OF REVIEW

This review examines recent cases and updated literature on emerging or newly resistant fungal infections in solid organ transplantation.

RECENT FINDINGS

Candida auris, a newly described candida capable of drug resistance and persistence in the environment, is a growing concern with both published cases on donor-derived transmission and a hospital outbreak involving liver transplant recipients. Infections with non-albicans candida species are also increasing in incidence in SOT recipients, leading to increasing antifungal resistance and higher mortality. Aspergillus usti has emerged in immunocompromised patients on antifungal prophylaxis. Cryptococcus species continue to be responsible for a number of infections in SOT recipients. Dimorphic fungi, endemic to geographic areas and responsible for sporadic infections in SOT recipients are noted to have an expanding geographic area. Emergomyces are newly classified groups of five species of dimorphic fungi noted to disseminated disease in immunocompromised patients including SOT recipients.

SUMMARY

Emerging fungal species and the development of resistance in well entrenched fungal pathogens impacts SOT recipients and those caring for them. Knowledge of these trends aids in the successful identification and optimal treatment of these challenging conditions.

Antimicrobial stewardship in the ICU in COVID times: the known unknowns

Since the start of the COVID-19 pandemic, there has been concern about the concomitant rise of antimicrobial resistance. While bacterial co-infections seem rare in COVID-19 patients admitted to hospital wards and intensive care units (ICUs), an increase in empirical antibiotic use has been described. In the ICU setting, where antibiotics are already abundantly—and often inappropriately—prescribed, the need for an ICU-specific antimicrobial stewardship programme is widely advocated. Apart from essentially warning against the use of antibacterial drugs for the treatment of a viral infection, other aspects of ICU antimicrobial stewardship need to be considered in view of the clinical course and characteristics of COVID-19. First, the distinction between infectious and non-infectious (inflammatory) causes of respiratory deterioration during an ICU stay is difficult, and the much-debated relevance of fungal and viral co-infections adds to the complexity of empirical antimicrobial prescribing. Biomarkers such as procalcitonin for the decision to start antibacterial therapy for ICU nosocomial infections seem to be more promising in COVID-19 than non-COVID-19 patients. In COVID-19 patients, cytomegalovirus reactivation is an important factor to consider when assessing patients infected with SARS-CoV-2 as it may have a role in modulating the patient immune response. The diagnosis of COVID-19-associated invasive aspergillosis is challenging because of the lack of sensitivity and specificity of the available tests. Furthermore, altered pharmacokinetic/pharmacodynamic properties need to be taken into account when prescribing antimicrobial therapy. Future research should now further explore the ‘known unknowns’, ideally with robust prospective study designs.

Biomarkers for the diagnosis of invasive candidiasis in immunocompetent and immunocompromised patients

Blood culture methods show low sensitivity, so reliable non-culture diagnostic tests are needed to help clinicians with the introduction, de-escalation, and discontinuation of antifungal therapy in patients with suspected invasive candidiasis (IC). We evaluated different biomarkers for the diagnosis of IC in immunocompetent and immunocompromised patients at risk for developing invasive fungal diseases. The specificity of Candida albicans germ-tube antibodies (CAGTA) detection was high (89%-100%), but sensitivity did not exceed 61% even after raising the cut-off from 1/160 to 1/80. We developed enzyme-linked immunoassays detecting antibodies against C. albicans proteins (Als3-N, Hwp1-N, or Met6) that resulted more sensitive (66%-92%) but less specific than CAGTA assay. The combination of 1,3-beta-D-glucan (BDG) detection and CAGTA results provided the highest diagnostic usefulness in immunocompetent patients. However, in immunocompromised patients, anti-Met6 antibodies was the best biomarker, both, alone or in combination with BDG.

Invasive aspergillosis and endocarditis

INTRODUCTION

Aspergillusfumigatus can cause a systemic infection called invasive aspergillosis causing pulmonary and extra-pulmonary damage. Aspergillus endocarditis (AE) is a relatively rare disease but can be life-threatening.

CASE REPORTS

We report here on five cases of endocarditis due to invasive aspergillosis: a 58-year-old man receiving immunosuppressive medication following a kidney graft, a 58-year-old man undergoing chemotherapy for chronic lymphocytic leukaemia, a 55-year-old man receiving corticosteroids for IgA vasculitis, a 52-year-old HIV-infected woman under no specific treatment and a 17-year-old boy under immunosuppressive therapy for auto-immune chronic neutropenia.

DISCUSSION

Aspergillus accounts for 25-30% of fungal endocarditis and 0.25% to 8.5% of all cases of infectious endocarditis. Aspergillus endocarditis results from invasion of the lung arterioles by hyphae and blood dissemination. It is associated with a very high mortality rate (42-68%). Diagnosing Aspergillus endocarditis is mainly problematic because blood cultures are almost always negative, and fever may be absent. Immunosuppression, haematological malignancies, recent cardiothoracic surgery, negative blood cultures with endocarditis and/or systemic or pulmonary emboli are predictors of AE. In the setting of endocarditis, some clinical characteristics may raise early suspicions of aspergillosis rather than a non-fungal agent: no fever, vegetations affecting the mitral valve, non-valve or aortotomy sites, aortic abscess or pseudo-aneurysm. The identification of invasive aspergillosis is based on a chest CT scan, microscopy/culture or other serological and molecular tests. The treatment of Aspergillus endocarditis requires triazole antifungal drugs, and frequently additional surgical debridement.

CONCLUSION

Aspergillus endocarditis is rare but is associated with a very high mortality rate. Knowledge of its predictive factors and key clinical features can help to differentiate aspergillosis from non-fungal endocarditis and may enable improved survival rates.

Successful, Combined Long-term Treatment of Cerebral Candidiasis and Aspergillosis in a Liver Transplant Recipient: A Case Report

Invasive fungal infections, of which the most common are candidiasis and aspergillosis, are among the most important and fatal complications in solid organ transplantation. They continue to be a significant cause of morbidity and mortality in patients with involvement of the central nervous system (CNS) because of the poor CNS penetration of antifungal medications. Voriconazole yields fungicidal drug concentrations in the CNS, but its use is limited in solid organ transplant patients because of its metabolic interactions with immunosuppression. Here we report a case of invasive fungal infection in the CNS after an emergency liver transplantation due to hepatitis B virus-related acute liver failure. The patient was managed successfully with a long-term conservative medical treatment.

Variation of virulence of five Aspergillus fumigatus isolates in four different infection models

Conidia of Aspergillus fumigatus are inhaled by humans on daily basis. As a consequence, these conidia can cause infections that differ in severity ranging from allergic bronchopulmonary aspergillosis to invasive aspergillosis. In this study we compared virulence of five A. fumigatus isolates in four different infection models to address the predictive value of different model systems. Two of the A. fumigatus strains were isolated from dogs with a non-invasive sino-nasal aspergillosis (DTO271-B5 and DTO303-F3), while three strains were isolated from human patients with invasive aspergillosis (Af293, ATCC46645 and CEA10). Infection models used encompassed cultured type II A549 lung epithelial cells, Protostelium aurantium amoeba, Galleria melonella larvae and zebrafish embryos. No major differences in virulence between these five strains were observed in the lung epithelial cell model. In contrast, strain ATCC46645 was most virulent in the amoeba and zebrafish model, whereas it was much less virulent in the Galleria infection model. DTO303-F3 was most virulent in the latter model. In general, reference strain Af293 was less virulent as compared to the other strains. Genome sequence analysis showed that this latter strain differed from the other four strains in 136 SNPs in virulence-related genes. Together, our results show that virulence of individual A. fumigatus strains show significant differences between infection models. We conclude that the predictive value of different model systems varies since the relative virulence across fungal strains does not hold up across different infection model systems.

How urgent is the need for new antifungals?

Introduction: Invasive fungal infection carries a high morbidity, mortality and economic cost. In recent times, a rising incidence of fungal infection and antifungal resistance is occurring which has prompted the development of novel antifungal agents.Areas covered:In this perspective, the authors describe the current status of registered antifungals and their limitations in the treatment of invasive fungal infection. They also go on to describe the new antifungal agents that are in the clinical stage of development and how they might be best utilized in patient care in the future.Expert opinion: The antifungal drug development pipeline has responded to a growing need for new agents to effectively treat fungal disease without concomitant toxicity or issues with drug tolerance. Olorofim (F901318), ibrexafungerp (SCY-078), fosmanogepix (APX001), rezafungin (CD101), oteseconazole (VT-1161), encochleated amphotericin B (MAT2203), nikkomycin Z (NikZ) and ATI-2307 are all in the clinical stage of development and offer great promise in offering clinicians better agents to treat these difficult infections.

Diagnosis of Pneumonia Due to Invasive Molds

Pneumonia is the most common presentation of invasive mold infections (IMIs), and is pathogenetically characterized as angioinvasion by hyphae, resulting in tissue infarction and necrosis. Aspergillus species are the typical etiologic cause of mold pneumonia, with A. fumigatus in most cases, followed by the Mucorales species. Typical populations at risk include hematologic cancer patients on chemotherapy, bone marrow and solid organ transplant patients, and patients on immunosuppressive medications. Invasive lung disease due to molds is challenging to definitively diagnose based on clinical features and imaging findings alone, as these methods are nonspecific. Etiologic laboratory testing is limited to insensitive culture techniques, non-specific and not readily available PCR, and tissue biopsies, which are often difficult to obtain and impact on the clinical fragility of patients. Microbiologic/mycologic analysis has limited sensitivity and may not be sufficiently timely to be actionable. Due to the inadequacy of current diagnostics, clinicians should consider a combination of diagnostic modalities to prevent morbidity in patients with mold pneumonia. Diagnosis of IMIs requires improvement, and the availability of noninvasive methods such as fungal biomarkers, microbial cell-free DNA sequencing, and metabolomics-breath testing could represent a new era of timely diagnosis and early treatment of mold pneumonia.

Antifungal activity of dendritic cell lysosomal proteins against Cryptococcus neoformans

Cryptococcal meningitis is a life-threatening disease among immune compromised individuals that is caused by the opportunistic fungal pathogen Cryptococcus neoformans. Previous studies have shown that the fungus is phagocytosed by dendritic cells (DCs) and trafficked to the lysosome where it is killed by both oxidative and non-oxidative mechanisms. While certain molecules from the lysosome are known to kill or inhibit the growth of C. neoformans, the lysosome is an organelle containing many different proteins and enzymes that are designed to degrade phagocytosed material. We hypothesized that multiple lysosomal components, including cysteine proteases and antimicrobial peptides, could inhibit the growth of C. neoformans. Our study identified the contents of the DC lysosome and examined the anti-cryptococcal properties of different proteins found within the lysosome. Results showed several DC lysosomal proteins affected the growth of C. neoformans in vitro. The proteins that killed or inhibited the fungus did so in a dose-dependent manner. Furthermore, the concentration of protein needed for cryptococcal inhibition was found to be non-cytotoxic to mammalian cells. These data show that many DC lysosomal proteins have antifungal activity and have potential as immune-based therapeutics.

Fungal Infections in Liver Transplant Recipients

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

Update on Pulmonary Cryptococcosis

Pulmonary cryptococcosis is a common but underdiagnosed opportunistic fungal infection in both immunocompromised and immunocompetent patients. The causal agents include at least eight evolutionary distinct haploid lineages as well as their hybrids of the human pathogenic Cryptococcus complex. In this update, we review recent advances in epidemiology, mode of transmission, risk factors, diagnostic methods, and therapy of pulmonary cryptococcosis. Our review suggests significant challenges and opportunities for research, from bedside to benchside and back to bedside.

Comparative activity of posaconazole and systemic azole agents against clinical isolates of filamentous fungi from a global surveillance programme

Objectives

The activity of mould-active azoles was evaluated against 397 filamentous fungi causing invasive mould infections (IMI) worldwide. In addition, a tentative posaconazole epidemiological cut-off value (ECV) against Aspergillus fumigatus was investigated.

Methods

Isolates were susceptibility tested by the CLSI reference broth microdilution methods. Species identification was confirmed by MALDI-TOF and/or sequencing analysis.

Results

Aspergillus spp. (81.9%) remained the most common organism causing IMI worldwide; approximately two-thirds of Aspergillus spp. recovered were A. fumigatus. In general, more than 90% of 220 A. fumigatus isolates were wild type (WT) to all mould-active azoles, except itraconazole (84.5% WT). The voriconazole non-susceptible (NS) A. fumigatus rate was 7.7% overall and was higher in Europe (12.9%) than in the other regions (0%–5.8%). Posaconazole (MIC₅₀/MIC₉₀, 0.25/0.5 mg/L) showed similar or slightly higher activity than voriconazole (MIC₅₀/MIC₉₀, 0.5/0.5 mg/L) and isavuconazole (MIC₅₀/MIC₉₀, 0.5/1 mg/L) against A. fumigatus. The mould-active azoles displayed similar activity against non-fumigatus Aspergillus (WT rates >93%), but differences were observed among the main species/sections. Posaconazole, voriconazole, and isavuconazole inhibited at their respective ECVs 100%, 97.0%, and 100% of A. section Nigri; 100%, 100%, and 93.8% of A. section Terrei; and 97.3%, 100%, and 100% of A. section Flavi isolates. Posaconazole displayed potency greater than or equal to the other azoles against the Mucorales group and Scedosporium spp.

Conclusions

Posaconazole and other mould-active azoles showed good activity against Aspergillus spp. causing IMI, but clinicians should be aware of regional rates of voriconazole-NS A. fumigatus.

Comparing posaconazole and itraconazole for antifungal prophylaxis in critically ill lung transplant recipients: Efficacy and plasma concentrations

BACKGROUND

Posaconazole and itraconazole are commonly used for systemic antifungal prophylaxis after lung transplantation. The aim of this study on critically ill lung transplant recipients was to assess the rate of adequate plasma concentrations and the frequency of fungal-induced transitions from antifungal prophylaxis to therapy after the administration of either posaconazole or itraconazole for systemic prophylaxis.

METHODS

Critically ill lung transplant recipients with postoperative posaconazole or itraconazole prophylaxis and therapeutic drug monitoring from February 2016 to November 2019 were retrospectively included in the study. Positive fungal cultures or Aspergillus antigen tests resulting in a transition from antifungal prophylaxis to therapy were analyzed from the first day of prophylaxis until 7 days after the last sample for each patient. Adequate plasma concentrations were defined as ≥500 µg/L for itraconazole and ≥700 µg/L for posaconazole.

RESULTS

Two hundred seventy-five samples from 73 patients were included in the analysis. Overall, 60% of the posaconazole and 55% of the itraconazole concentrations were subtherapeutic. Administration of posaconazole suspension resulted significantly (P < .01) more often in subtherapeutic concentrations than tablets (68% vs 10%). Patients treated with posaconazole showed less positive fungal records resulting in a transition from prophylaxis to therapy than patients treated with itraconazole (10% vs 33%, P-value: .029). The detection of a fungal pathogen was not associated with the measured plasma concentrations or the achievement of the target concentrations.

CONCLUSION

Our findings suggest that posaconazole should be used instead of itraconazole for systemic prophylaxis in critically ill lung transplant recipients.

Establishing essential metrics for antifungal stewardship in hospitals: the results of an international Delphi survey

BACKGROUND

Guidance on assessment of the quantity and appropriateness of antifungal prescribing is required to assist hospitals to interpret data effectively and structure quality improvement programmes.

OBJECTIVES

To achieve expert consensus on a core set of antifungal stewardship (AFS) metrics and to determine their feasibility for implementation.

METHODS

A literature review was undertaken to develop a list of candidate metrics. International experts were invited to participate in sequential web-based surveys to evaluate the importance and feasibility of metrics in the area of AFS using Delphi methodology. Three surveys were completed. Consensus was predefined as ≥80% agreement on the importance of each metric.

RESULTS

Eighty-two experts consented to participate from 17 different countries. Response rate for each survey was >80%. The panel included adult and paediatric physicians, microbiologists and pharmacists with diverse content expertise. Consensus was achieved for 38 metrics considered important to routinely include in AFS programmes, and related to antifungal consumption (n = 5), quality of antifungal prescribing and management of invasive fungal infection (IFI) (n = 24), and clinical outcomes (n = 9). Twenty-one consensus metrics were considered to have moderate to high feasibility for routine collection.

CONCLUSIONS

The identified core AFS metrics will provide a framework to comprehensively assess the quantity and quality of antifungal prescribing within hospitals to develop quality improvement programmes aimed at improving IFI prevention, management and patient-centred outcomes. A standardized approach will support collaboration and benchmarking to monitor the efficacy of current prophylaxis and treatment guidelines, and will provide important feedback to guideline developers.

Changing demographics and risk factors for cryptococcosis: A 12-year review at a tertiary care centre

BACKGROUND

Cryptococcosis is classically associated with the immunocompromised patients but there is a rising appreciation for its impact on the immunocompetent hosts. We sought to analyse the trends, diagnosis, treatment of different hosts and the effect of immunodeficiency and chronic liver disease on relapse and in-house mortality.

METHODS

This is a retrospective study of 12 years of patients with cryptococcosis, divided into three different groups: HIV-infected, transplant and non-HIV non-transplant (NHNT). Data were analysed with Chi-square, unpaired parametric t test, simple and multivariate logistic regression analysis.

RESULTS

Of 114 identified patients, 23 (20.2%) had HIV infection, 11 (9.6%) had transplant, 80 (70.2%) were NHNT patients. Overall, mortality was 28.1% (32/114) and relapse occurred in 10.5% (12/114) of patients. The mortality trend was higher (OR = 2.346, p = .287) in the transplant group (45.5%, 5/11) than in HIV (26.1%, 6/23) and NHNT groups (26.3%, 21/80). HIV was associated with relapse; 30.4% (7/23) for HIV-positive patients and 5.5% (5/91) for HIV-negative patients (OR = 7.525, p = .002). Chronic liver disease had a large and statistically significant association with mortality on multivariate analysis (OR = 3.583, p = .013) which was more pronounced than the HIV or transplant groups. It was independently associated with mortality by chi-square analysis (OR 3.137, p = .012).

CONCLUSION

Chronic liver disease represented 30.7% (35/114) of all studied patients. It was a risk factor for in-hospital mortality. HIV infection and transplant were not statistically significant for mortality. Relapse was highest in the HIV-infected patients at 30.4% (7/23). These data highlight the effect of type and degree of immunocompromise on cryptococcosis.

Reinforcing the Immunocompromised Host Defense against Fungi: Progress beyond the Current State of the Art

Despite the availability of a variety of antifungal drugs, opportunistic fungal infections still remain life-threatening for immunocompromised patients, such as those undergoing allogeneic hematopoietic cell transplantation or solid organ transplantation. Suboptimal efficacy, toxicity, development of resistant variants and recurrent episodes are limitations associated with current antifungal drug therapy. Adjunctive immunotherapies reinforcing the host defense against fungi and aiding in clearance of opportunistic pathogens are continuously gaining ground in this battle. Here, we review alternative approaches for the management of fungal infections going beyond the state of the art and placing an emphasis on fungus-specific T cell immunotherapy. Harnessing the power of T cells in the form of adoptive immunotherapy represents the strenuous protagonist of the current immunotherapeutic approaches towards combating invasive fungal infections. The progress that has been made over the last years in this field and remaining challenges as well, will be discussed.

Morphological and genetic identification of fungal genus/species in formalin-fixed, paraffin-embedded specimens obtained from patients with histologically proven fungal infection

BACKGROUND

Although fungi are found relatively easily by microscopic examination of pathological samples, identification of fungal genus and species in pathological samples is not easy because the morphological features of fungi are similar among genera and species.

OBJECTIVES

A multiple real-time PCR was developed for identification of fungal genus/species, and morphological characterizations of fungi were analysed in pathological samples.

PATIENTS/METHODS

Seventy-five formalin-fixed paraffin-embedded (FFPE) samples morphologically proven to contain any fungus were examined. A multiple real-time PCR system was developed to identify 25 fungal genus/species in pathological samples. Morphology of fungus in the specimens was re-reviewed retrospectively based on the results of real-time PCR.

RESULTS

Real-time PCR identified fungal genus/species in 56 of 75 (74.6%) specimens with histologically proven fungal infection. In 53 specimens of filamentous fungi, Aspergillus spp. (22 specimens), Cladosporium (8), Scedosporium apiospermum (4), Malassezia sympodialis (1) and Candida albicans (1) were identified. Pseudohyphae of Candida were confused with filamentous fungus in a case. Morphological observation suggested differences in the presence of septated or non-septated hyphae, the filament size, and the branch angle among genus/species of filamentous fungi; however, genus/species was not able to be determined by their morphological features. In 22 specimens of yeasts, real-time PCR allowed for the identification of Candida albicans (12 specimens), Candida glabrata (2), Cladosporium (2), Scedosporium apiospermum (2), Pichia kudriavzevii (1) and Aspergillus sydowii (1).

CONCLUSIONS

These data suggest that it is difficult to identify fungal genus/species by morphological features alone. Real-time PCR is useful to identify fungal genus/species in pathological samples.

Reactivation of latent infections in solid organ transplant recipients from sub-Saharan Africa: What should be remembered?

International migration from Sub-Saharan African countries to the European Union and the United States has significantly increased over the past decades. Although the vast majority of these immigrants are young and healthy people, a minority can be affected by chronic conditions eventually leading to solid organ transplantation (SOT). Importantly, these candidates can bear geographically restricted fungal and parasitic latent infections that can reactivate after the procedure. An appropriate evaluation before transplantation followed by treatment, whenever necessary, is essential to minimize such risk, as covered in the present review. In short, infection due to helminths (Schistosoma spp. and Strongyloides stercoralis) and intestinal protozoa (Entamoeba histolytica, Giardia lamblia or Cyclospora cayetanensis) can be diagnosed by multiple direct stool examination, serological assays and stool antigen testing. Leishmaniasis can be assessed by means of serology, followed by nucleic acid amplification testing (NAAT) if the former test is positive. Submicroscopic malaria should be ruled out by NAAT. Screening for Histoplasma spp. or Cryptococcus spp. is not routinely indicated. Consultation with an Infectious Diseases specialist is recommended in order to adjust preemptive treatment among Sub-Saharan African SOT candidates and recipients.

Donor-derived renal allograft mucormycosis in a combined liver and kidney transplantation: Case report and review of the literature

Mucormycosis infrequently may present with isolated renal involvement. Among solid organ transplant recipients, renal allograft mucormycosis has been most often associated with medical tourism or transplantation outside of the western world. We report a case of an HIV/HCV co-infected woman who underwent simultaneous liver and kidney transplantation with a Public Health Service increased risk donor organ. 16 days after transplant, she developed massive hematuria and was found to have renal allograft Rhizopus spp. involvement, we surmise to have been from donor-derived infection. Therapy included nephrectomy, debridement, liposomal amphotericin B, and posaconazole with survival. We reviewed PubMed indexed, English-language cases of isolated renal mucormycosis in general, in HIV/AIDS, and from donor-derived renal allograft infections.

Infectious Gastroenteritis in Transplant Patients

Infectious gastroenteritis is common after transplantation and can lead to increased morbidity and mortality. A wide range of organisms can lead to gastroenteritis in this patient population. Clostridioides difficile, cytomegalovirus, and norovirus are the most common pathogens. Newer diagnostic methods, especially multiplex polymerase chain reaction, have increased the diagnostic yield of infectious etiologies. In this review, we describe the epidemiology and risk factors for common infectious pathogens leading to gastroenteritis.

Mucormycosis after Coronavirus disease 2019 infection in a heart transplant recipient - Case report and review of literature

Mucormycosis is an invasive fungal infection (IFI) due to several species of saprophytic fungi, occurring in patients with underlying co-morbidities (including organ transplantation). During the ongoing Coronavirus disease 2019 (COVID-19) pandemic, there have been increasing reports of bacterial and fungal co-infections occurring in COVID-19 patients, including COVID-19 associated pulmonary aspergillosis (CAPA). We describe a case of mucormycosis occurring after COVID-19, in an individual who received a recent heart transplant for severe heart failure. Two months after heart transplant, our patient developed upper respiratory and systemic symptoms and was diagnosed with COVID-19. He was managed with convalescent plasma therapy and supportive care. Approximately three months after COVID-19 diagnosis, he developed cutaneous mucormycosis at an old intravascular device site. He underwent extensive surgical interventions, combined with broad-spectrum antifungal therapy. Despite the aggressive therapeutic measures, he died after a prolonged hospital stay. In this case report, we also review the prior well-reported cases of mucormycosis occurring in COVID-19 patients and discuss potential mechanisms by which COVID-19 may predispose to IFIs. Similar to CAPA, mucormycosis with COVID-19 may need to be evaluated as an emerging disease association. Clinicians should be vigilant to evaluate for invasive fungal infections such as mucormycosis in patients with COVID-19 infection.

Mucormycosis

Mucormycosis is a rare but aggressive fungal disease that mainly affects patients with poorly controlled diabetes mellitus and those who are severely immunocompromised, including patients with hematological malignancies and solid organ transplant recipients. Early recognition of infection is critical for treatment success, followed by prompt initiation of antifungal therapy with lipid formulation amphotericin B. Posaconazole and isavuconazole should be used for stepdown and salvage therapy. Surgical debridement is key for tissue diagnosis and treatment and should be pursued urgently whenever possible. In addition to surgery and antifungal therapy, reverting the underlying risk factor for infection is important for treatment response.

Fungal pneumonia in kidney transplant recipients

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

Mucormycosis associated with COVID-19 in two kidney transplant patients

Coronavirus disease 2019 (COVID‐19) predisposes patients to bacterial and fungal superinfections due to the impairment of the immunological system. Among the associated opportunistic fungal infections, mucormycosis is one of the least frequent but with the highest mortality. We describe two cases of mucormycosis in two kidney transplant recipients, while they were hospitalized for SARS‐CoV‐2 pneumonia, with rhinosinusal and musculoskeletal involvement, respectively.

Fungal Infection in an Exenterated Orbit

A 48-year-old man presented with an Aspergillus fumigatus complex infection of an exenterated orbit. The OS had been exenterated 7 months ago, together with total parotidectomy and neck dissection followed by irradiation due to a massive squamous cell carcinoma with orbital invasion and lymphatic metastasis. The patient was under permanent immunosuppression with oral prednisone and tacrolimus due to a kidney transplantation 5 years ago. The infected skin of the exenterated orbit was cleared using forceps. MRI ruled out any bone infiltration. After systemic treatment with oral voriconazole and topical therapy with bifonazole ointment for 6 weeks, the patient recovered completely.

Invasive pulmonary aspergillosis associated with viral pneumonitis

The occurrence of invasive pulmonary aspergillosis (IPA) in critically ill patients with viral pneumonitis has increasingly been reported in recent years. Influenza-associated pulmonary aspergillosis (IAPA) and COVID-19-associated pulmonary aspergillosis (CAPA) are the two most common forms of this fungal infection. These diseases cause high mortality in patients, most of whom were previously immunocompetent. The pathogenesis of IAPA and CAPA is still not fully understood, but involves viral, fungal and host factors. In this article, we discuss several aspects regarding IAPA and CAPA, including their possible pathogenesis, the use of immunotherapy, and future challenges.

Invasive Aspergillosis Due to Aspergillus Section Usti: A Multicenter Retrospective Study

BACKGROUND

Aspergillus spp. of section Usti (A. ustus) represent a rare cause of invasive aspergillosis (IA). This multicenter study describes the epidemiology and outcome of A. ustus infections.

METHODS

Patients with A. ustus isolated from any clinical specimen were retrospectively identified in 22 hospitals from 8 countries. When available, isolates were sent for species identification (BenA/CaM sequencing) and antifungal susceptibility testing. Additional cases were identified by review of the literature. Cases were classified as proven/probable IA or no infection, according to standard international criteria.

RESULTS

Clinical report forms were obtained for 90 patients, of whom 27 had proven/probable IA. An additional 45 cases were identified from literature review for a total of 72 cases of proven/probable IA. Hematopoietic cell and solid-organ transplant recipients accounted for 47% and 33% cases, respectively. Only 8% patients were neutropenic at time of diagnosis. Ongoing antimold prophylaxis was present in 47% of cases. Pulmonary IA represented 67% of cases. Primary or secondary extrapulmonary sites of infection were observed in 46% of cases, with skin being affected in 28% of cases. Multiple antifungal drugs were used (consecutively or in combination) in 67% of cases. The 24-week mortality rate was 58%. A. calidoustus was the most frequent causal agent. Minimal inhibitory concentrations encompassing 90% isolates (MIC90) were 1, 8, >16, and 4 µg/mL for amphotericin B, voriconazole, posaconazole, and isavuconazole, respectively.

CONCLUSIONS

Aspergillus ustus IA mainly occurred in nonneutropenic transplant patients and was frequently associated with extrapulmonary sites of infection. Mortality rate was high and optimal antifungal therapy remains to be defined.

Vaccine-Induced Protection in Two Murine Models of Invasive Pulmonary Aspergillosis

Life-threatening, invasive fungal infections (IFIs) cause over 1.5 million deaths worldwide and are a major public health concern with high mortality rates even with medical treatment. Infections with the opportunistic fungal pathogen, Aspergillus fumigatus are among the most common. Despite the growing clinical need, there are no licensed vaccines for IFIs. Here we evaluated the immunogenicity and protective efficacy of an A. fumigatus recombinant protein vaccine candidate, AF.KEX1, in experimental murine models of drug-induced immunosuppression. Immunization of healthy mice with AF.KEX1 and adjuvant induced a robust immune response. Following AF.KEX1 or sham immunization, mice were immunosuppressed by treatment with either cortisone acetate or hydrocortisone and the calcineurin inhibitor, tacrolimus. To test vaccine efficacy, immunosuppressed mice were intranasally challenged with A. fumigatus conidia (Af293) and weight and body temperature were monitored for 10 days. At study termination, organism burden in the lungs was evaluated by quantitative PCR and Gomori's methanamine silver staining. In both models of immunosuppression, AF.KEX1 vaccinated mice experienced decreased rates of mortality and significantly lower lung organism burden compared to non-vaccinated controls. The lung fungal burden was inversely correlated with the peak anti-AF.KEX1 IgG titer achieved following vaccination. These studies provide the basis for further evaluation of a novel vaccine strategy to protect individuals at risk of invasive aspergillosis due to immunosuppressive treatments.

Cryptococcus neoformans meningitis in kidney transplant recipients: A diagnostic and therapeutic challenge

Cryptococcosis is the third most common invasive fungal infection in solid organ transplant recipients. We describe three cases of neuro-meningeal cryptococcosis occurring among kidney transplant (KT) patients, and discuss the diagnostic and therapeutic challenges in this context. Median time from KT to infection was 6 months [range: 3-9]. The most common clinical manifestations at diagnosis were fever (2/3), headache (2/3), and confusion (2/3); none had extra-neurological involvement. CrAg was positive in all cases at diagnosis both in serum and cerebrospinal fluid (CSF). For two patients, analysis of previous samples showed that CrAg was detected in plasma up to 4 weeks before diagnosis. All patients received induction treatment with liposomal amphotericin-B (L-AmB) and flucytosine for a median duration of 10 days [range: 7-14], followed by fluconazole maintenance therapy. Acute kidney injury secondary to L-AmB therapy was observed in only one case, but all patients had a tacrolimus overdose following initiation of maintenance therapy due to drug-drug interactions between fluconazole and tacrolimus. Among KTR, early detection of Cryptococcus meningitis using serum CrAg is possible. Close monitoring of renal function during treatment is essential due to the nephrotoxicity of L-AmB, but also drug-drug interactions between fluconazole and calcineurin inhibitors.

Diagnostic Capacity for Invasive Fungal Infections in the Greek Paediatric Haematology-Oncology Units: Report from the Infection Working Group of the Hellenic Society of Paediatric Haematology-Oncology

An audit based on a specific questionnaire was attempted, in order to investigate the mycology laboratory diagnostic capacity for invasive fungal diseases (IFDs) in Greek Paediatric Haematology-Oncology departments/units. The study provided the relevant information for the years 2019 and 2020 and included data from all units, concerning culture-based methods and direct microscopy, phenotypic and molecular identification, sensitivity testing, serology and molecular diagnosis, as well as therapeutic drug monitoring. The target was mostly to reveal the level of laboratory coverage for hospitalised paediatric patients, independently of the possibility of performing the tests in the host hospital, or otherwise to refer the specimens elsewhere. In total, the current study demonstrated that the most important facilities and services regarding the IFD diagnostics for paediatric haematology-oncology patients in Greece are available and relatively easily accessible, with a reasonable turnaround time. Acting as an initial registry for further improvements, the audit can serve as a valuable approach to the actual situation and future perspectives. A national clinical mycology network under the auspices of the relevant scientific societies will probably facilitate collaboration between all the departments (clinical and laboratory) involved in invasive fungal infections and provide an easier approach to any necessary test for any hospitalised patient.

Trends in Agricultural Triazole Fungicide Use in the United States, 1992-2016 and Possible Implications for Antifungal-Resistant Fungi in Human Disease

BACKGROUND

The fungus Aspergillus fumigatus (A. fumigatus) is the leading cause of invasive mold infections, which cause severe disease and death in immunocompromised people. Use of triazole antifungal medications in recent decades has improved patient survival; however, triazole-resistant infections have become common in parts of Europe and are emerging in the United States. Triazoles are also a class of fungicides used in plant agriculture, and certain triazole-resistant A. fumigatus strains found causing disease in humans have been linked to environmental fungicide use.

OBJECTIVES

We examined U.S. temporal and geographic trends in the use of triazole fungicides using U.S. Geological Survey agricultural pesticide use estimates.

DISCUSSION

Based on our analysis, overall tonnage of triazole fungicide use nationwide was relatively constant during 1992-2005 but increased >4-fold during 2006-2016 to 2.9 million kg in 2016. During 1992-2005, triazole fungicide use occurred mostly in orchards and grapes, wheat, and other crops, but recent increases in use have occurred primarily in wheat, corn, soybeans, and other crops, particularly in Midwest and Southeast states. We conclude that, given the chemical similarities between triazole fungicides and triazole antifungal drugs used in human medicine, increased monitoring for environmental and clinical triazole resistance in A. fumigatus would improve overall understanding of these interactions, as well as help identify strategies to mitigate development and spread of resistance. https://doi.org/10.1289/EHP7484.