ESCMID-ECMM guideline: diagnosis and management of invasive aspergillosis in neonates and children

Inappropriate treatment of pulmonary aspergillosis caused by Aspergillus flavus in susceptible pediatric patients: a case series

BACKGROUND

Pulmonary aspergillosis is a prevalent opportunistic fungal infection that can lead to mortality in pediatric patients with underlying immunosuppression. Appropriate and timely treatment of pulmonary aspergillosis can play a crucial role in reducing mortality among children admitted with suspected infections.

CASE PRESENTATION

The present study reports three cases of inappropriate treatment of pulmonary aspergillosis caused by Aspergillus flavus in two Iranian pediatric patients under investigation and one Afghan patient. Unfortunately, two of them died. The cases involved patients aged 9, 1.5, and 3 years. They had been diagnosed with pulmonary disorders, presenting nonspecific clinical signs and radiographic images suggestive of pneumonia. The identification of A. flavus was confirmed through DNA sequencing of the calmodulin (CaM) region.

CONCLUSION

A. flavus was the most prevalent cause of pulmonary aspergillosis in pediatric patients. Early diagnosis and accurate antifungal treatment of pulmonary aspergillosis could be crucial in reducing the mortality rate and also have significant potential for preventing other complications among children. Moreover, antifungal prophylaxis seems to be essential for enhancing survival in these patients.

Is there still a place for serum galactomannan in the diagnosis of invasive aspergillosis in children at high risk and under antifungal prophylaxis?

BACKGROUND

The performance of serum galactomannan (GM) for the diagnosis of invasive aspergillosis (IA) has been studied mainly in adults. Paediatric data are scarce and based on small and heterogeneous cohorts.

OBJECTIVE

To evaluate the performance of serum GM for the diagnosis of IA in a paediatric oncologic population at high risk of IA and to clarify the impact of antifungal prophylaxis on this test.

METHODS

We performed a retrospective study from January 2014 to December 2020 in the paediatric oncologic haematologic department of the University Hospital of Bordeaux. The diagnosis of IA was made using the recommendations of the EORTC and the MSGERC.

RESULTS

Among the 329 periods at high risk of IA in 222 patients, the prevalence of IA was 1.8% (3 proven and 3 probable IA). In the total population, the sensitivity, and the positive predictive value (PPV) were respectively 50% and 17.6%. Under antifungal prophylaxis, the sensitivity and PPV dropped, respectively, to 33.3% and 14.3%. In this group, the post-test probability of IA was 2% for a negative serum GM and only 14%.

CONCLUSION

In this large cohort of children at high risk of IA, the incidence of IA is low and the diagnostic performance of GM is poor, especially in the case of mould-active prophylaxis. Screening should be targeted rather than systematic and should be reserved for patients at highest risk for IA without mould-active prophylaxis. Combination with other tests such as Aspergillus PCR would increase the accuracy of GM in screening setting.

Clinical application of voriconazole in pediatric patients: a systematic review

The purpose of this study was to review the literature on the clinical use of voriconazole (VRC) in pediatric patients. MEDLINE, Embase, PubMed, Web of Science, and Cochrane Library were searched from January 1, 2000, to August 15, 2023 for relevant clinical studies on VRC use in pediatric patients. Data were collected based on inclusion and exclusion criteria, and a systematic review was performed on recent research related to the use of VRC in pediatric patients. This systematic review included a total of 35 observational studies among which there were 16 studies investigating factors influencing VRC plasma trough concentrations (Ctrough) in pediatric patients, 14 studies exploring VRC maintenance doses required to achieve target range of Ctrough, and 11 studies focusing on population pharmacokinetic (PPK) research of VRC in pediatric patients. Our study found that the Ctrough of VRC were influenced by both genetic and non-genetic factors. The optimal dosing of VRC was correlated with age in pediatric patients, and younger children usually required higher VRC doses to achieve target Ctrough compared to older children. Establishing a PPK model for VRC can assist in achieving more precise individualized dosing in children.

Humans vs. Fungi: An Overview of Fungal Pathogens against Humans

Human fungal diseases are infections caused by any fungus that invades human tissues, causing superficial, subcutaneous, or systemic diseases. Fungal infections that enter various human tissues and organs pose a significant threat to millions of individuals with weakened immune systems globally. Over recent decades, the reported cases of invasive fungal infections have increased substantially and research progress in this field has also been rapidly boosted. This review provides a comprehensive list of human fungal pathogens extracted from over 850 recent case reports, and a summary of the relevant disease conditions and their origins. Details of 281 human fungal pathogens belonging to 12 classes and 104 genera in the divisions ascomycota, basidiomycota, entomophthoromycota, and mucoromycota are listed. Among these, Aspergillus stands out as the genus with the greatest potential of infecting humans, comprising 16 species known to infect humans. Additionally, three other genera, Curvularia, Exophiala, and Trichophyton, are recognized as significant genera, each comprising 10 or more known human pathogenic species. A phylogenetic analysis based on partial sequences of the 28S nrRNA gene (LSU) of human fungal pathogens was performed to show their phylogenetic relationships and clarify their taxonomies. In addition, this review summarizes the recent advancements in fungal disease diagnosis and therapeutics.

ANTIFON-CLIC®, a new clinical decision support system for the treatment of invasive aspergillosis: is it clinically relevant?

BACKGROUND

Invasive aspergillosis (IA) is increasing especially in new groups of patients. Despite advances in management, morbidity and mortality related to IA remain high. Thus, Clinical Decision Support System (CDSS) dedicated to IA are needed to promote the optimal antifungal for each group of patients.

PATIENTS AND METHODS

This was a retrospective multicenter cohort study involving intensive care units and medical units. Adult patients who received caspofungin, isavuconazole, itraconazole, liposomal amphotericin B, posaconazole, or voriconazole, for the treatment of IA were eligible for enrollment. The primary objective was the concordance between the clinician's prescription and the prescription recommended by the CDSS. The secondary objective was the concordance according to different hospitals, departments, and indications.

RESULTS

Eighty-eight patients (n=88) from three medical hospitals were included. The overall concordance was 97% (85/88) including 100% (41/41) for center A, 92% (23/25) for center B, and 95% (21/22) for center C. There was no significant difference in concordance among the hospitals (P=0.973), the departments (P=1.000), and the indications (P=0.799). The concordance was 70% (7/10) for isavuconazole due to its use as an empirical treatment and 100% (78/78) for the other antifungals.

DISCUSSION

The concordance rate was high whatever the hospital, the department, and the indication. The only discrepancy was attributed to the use of isavuconazole as an empirical treatment which is a therapeutic option not included in the CDSS.

CONCLUSIONS

This new CDSS dedicated to IA is meeting the clinical practice. Its implementation in routine will help to support antifungal stewardship.

Amphotericin B in the Era of New Antifungals: Where Will It Stand?

Amphotericin B (AmB) has long stood as a cornerstone in the treatment of invasive fungal infections (IFIs), especially among immunocompromised patients. However, the landscape of antifungal therapy is evolving. New antifungal agents, boasting novel mechanisms of action and better safety profiles, are entering the scene, presenting alternatives to AmB's traditional dominance. This shift, prompted by an increase in the incidence of IFIs, the growing demographic of immunocompromised individuals, and changing patterns of fungal resistance, underscores the continuous need for effective treatments. Despite these challenges, AmB's broad efficacy and low resistance rates maintain its essential status in antifungal therapy. Innovations in AmB formulations, such as lipid complexes and liposomal delivery systems, have significantly mitigated its notorious nephrotoxicity and infusion-related reactions, thereby enhancing its clinical utility. Moreover, AmB's efficacy in treating severe and rare fungal infections and its pivotal role as prophylaxis in high-risk settings highlight its value and ongoing relevance. This review examines AmB's standing amidst the ever-changing antifungal landscape, focusing on its enduring significance in current clinical practice and exploring its potential future therapeutic adaptations.

Primary Mold-Active Antifungal Prophylaxis Decreases the Need for Chest Computed Tomography Scans in Patients with Acute Lymphoblastic Leukemia

Current guidelines recommend computed tomography (cCT) scans of the chest in children with leukemia following 96 h of the onset of idiopathic neutropenia to eliminate pulmonary invasive fungal infections (IFIs). However, cCT exposes some children who are at a very high risk of developing secondary cancers to radiation. We aimed to determine the effect of antifungal prophylaxis (AFP) with voriconazole (VCZ) on the need for cCT scans in children with acute lymphoblastic leukemia (ALL) to eliminate pulmonary IFIs during chemotherapy. We retrospectively screened all patients' data from their electronic charts. Children who were diagnosed as having ALL before February 2013 and did (AFP group) or did not (NoP group) receive AFP were divided into two groups and compared regarding cCT scans and relapse-mortality rates. Ninety-six children were diagnosed before February 2013 and did not receive primary AFP and 146 children were administered VCZ following a diagnosis of ALL. There were no significant demographic differences between the groups. A total of 128 cCTs had been required in 62 children in the NoP group, compared with 64 cCTs in 52 children in the AFP group. The percentage of the patients who had required at least one chest CT scan and the mean number of cCT scans in the NoP group were significantly higher compared with the AFP group. Proven-probable IFIs and relapse-mortality rates were higher in the NoP group compared with the AFP group. Mold-active AFP revealed a significant decrease in the need for cCT scans in children with ALL.

Overview of invasive fungal infections in children in South America - the threat of resistant Candida species and the role of climate change in the new geographic distribution of endemic systemic mycosis

PURPOSE OF REVIEW

Invasive fungal infection (IFI) in children is a growing problem with crescent morbidity and mortality, well recognized in developed countries, affecting mainly immunocompromised children, including neonates and children in intensive care units. The burden of IFI in South American children is less well comprehended. In addition, the current epidemiology of endemic systemic mycoses in children may have changed over time.

RECENT FINDINGS

Candida spp. infections are very prevalent in South America hospitalized children, especially in neonates, in a rate far superior compared to developed countries. C. auris, has already been responsible for outbreaks in neonates and children in Venezuela and Colombia. Sporotrichosis is well established as an urban zoonosis in impoverish families. Paracoccidioidomycosis and histoplasmosis are affecting new areas of Brazil, probably due to climate change, deforestation, and human migration.

SUMMARY

This review aims to unveil the real dimension of these infections in South American children. Hopefully, the awareness brought by this review will help healthcare professionals to recognize IFI more easily and it will provide support for getting more resources for IFI treatment and prevention.

Clinical performance of metagenomic next-generation sequencing for diagnosis of invasive fungal disease after hematopoietic cell transplant

Background

Timely diagnosis and appropriate antifungal therapy are critical for improving the prognosis of patients with invasive fungal disease (IFD) after hematopoietic stem cell transplantation (HSCT). We evaluated the performance of metagenomic next-generation sequencing (mNGS) and conventional microbiological testing (CMT), as well as the diagnosis, therapeutic management, and outcomes of IFD after HSCT.

Methods

We retrospectively studied 189 patients who underwent HSCT and were considered at risk for IFD. In total, 46 patients with IFD were enrolled in this study. The IFD consensus was followed for classifying IFD incidents.

Results

Forty-six patients were diagnosed with proven/probable (n = 12), possible (n = 27), and undefined (n = 7) IFD. Aspergillus was the most commonly detected fungal genus. Mucormycosis was found in 15 patients; two had Aspergillus, and one had Candida infections. Compared to CMT, mNGS significantly reduced the time required to identify pathogens (P = 0.0016). mNGS had a much higher sensitivity than CMT (84.78% vs. 36.96%; P < 0.0001). A total of 76.09% of patients received antifungal prophylaxis during fungal infections. All Pneumocystis infections occurred later than 100 days after transplantation. Among patients with Pneumocystis infection, 71.43% occurred following sulfonamide withdrawal, and subsequent treatment with sulfonamide alone or in combination with other drugs was effective. Based on the empirical antifungal treatment, the dosages, modes of administration, frequency of administration, or antifungal of 55.26% of the patients were changed according to the mNGS results. The 4-year overall survival rate of patients diagnosed with IFD after transplantation was 71.55% (95% CI, 55.18%-85.82%). Hypoproteinemia and corticosteroid use are independent risk factors for IFD.

Conclusion

mNGS, which has a high sensitivity and a short detection time, aids in the diagnosis and prognosis of pathogenic fungi. As a powerful technology, mNGS can influence treatment decisions in patients with IFD following HSCT.

Diagnostic limitations and challenges in current clinical guidelines and potential application of metagenomic sequencing to manage pulmonary invasive fungal infections in patients with haematological malignancies

BACKGROUND

Pulmonary invasive fungal infections (pIFI) disproportionately affect patients with haematological malignancies (HM). Establishing a rapid and accurate diagnosis of pIFI is challenging. Multiple guidelines recommend diagnostic testing of invasive fungal infections but lack consensus and may contribute to inconsistent diagnostic approaches.

OBJECTIVE

To identify key diagnostic challenges and review metagenomic sequencing data.

SOURCES

PubMed, professional consortium, and scientific society websites search to identify relevant, published, evidence-based clinical guidelines within the past 5 years. PubMed searchs for papers describing clinically relevant novel diagnostic technologies.

CONTENT

Current guidelines for patients with HM and suspected pIFI recommend chest computed tomography imaging and specimen testing with microscopic examination (including calcofluor white stain, histopathology, cytopathology, etc.), Aspergillus galactomannan, β-D-glucan, PCR, and culture, each with certain limitations. Emerging real-world data support the adjunctive use of metagenomic sequencing-based tests for the timely diagnosis of pIFI.

IMPLICATIONS

High-quality evidence from robust clinical trials is needed to determine whether guidelines should be updated to include novel diagnostic technologies. Trials should ask whether the combination of powerful novel diagnostics, such as pathogen-agnostic metagenomic sequencing technologies in conjunction with conventional testing can optimize the diagnostic yield for all potential pIFI pathogens that impact the health of patients with HM.

Trends in the activity of mold-active azole agents against Aspergillus fumigatus clinical isolates with and without cyp51 alterations from Europe and North America (2017-2021)

Azole resistance in Aspergillus fumigatus (AFM) is increasing and often associated with cyp51 alterations. We evaluated the activity of isavuconazole and other mold-active azoles against 731 AFM isolates causing invasive aspergillosis collected in Europe (EU; n = 449) and North America (NA; n = 282). Isolates were submitted to CLSI susceptibility testing and epidemiological cutoff value (ECV) criteria. A posaconazole ECV of 0.5 mg/L was used as no CLSI ECV was determined. Azole non-wild-type (NWT) isolates were submitted for cyp51 sequencing by whole genome sequencing. Overall, isavuconazole activity (92.7%/94.0% WT in EU/NA) was comparable to other azoles (WT rate range, 90.9%-96.4%/91.8%-98.6%, respectively), regardless of the region. A total of 79 (10.8%) azole NWT isolates were detected, and similar rates of these isolates were noted in EU (10.7%) and NA (11.0%). Although most AFM were WT to azoles, increasing azole NWT rates were observed in NA (from 6.0% in 2017 to 29.3% in 2021). Azole NWT rates varied from 4.9% (2019) to 20.6% (2018) in EU without an observed trend. cyp51 alterations occurred in 56.3%/54.8% of azole NWT from EU/NA, respectively. The cyp51A TR34/L98H alteration was observed only in EU isolates (72.0% of EU isolates), while cyp51A I242V occurred only in NA isolates (58.3%). Isavuconazole remained active (MIC, ≤1 mg/L) against 18.5/47.1% of azole NWT AFM exhibiting cyp51 alterations in EU/NA, along with voriconazole (29.6/82.4%; MIC, ≤1 mg/L) and posaconazole (48.1/88.2%; MIC, ≤0.5 mg/L). Fourteen different cyp51 alterations were detected in 44 of 79 NWT isolates. The in vitro activity of the azoles varied in AFM that displayed cyp51 alterations. IMPORTANCE A few microbiology laboratories perform antifungal susceptibility testing locally for systemically active antifungal agents. The identification of emerging azole-resistant Aspergillus fumigatus is worrisome. As such, there is a critical role for antifungal surveillance in tracking emerging resistance among both common and uncommon opportunistic fungi. Differences in the regional prevalence and antifungal resistance of these fungi render local epidemiological knowledge essential for the care of patients with a suspected invasive fungal infection.

Gaps in diagnosing suspected infection in immunocompromised children with cancer: A systematic review

While the survival of children with cancer has improved over time, infection remains a major morbidity and mortality risk. We conducted a systematic literature review to determine the unmet needs in diagnosing infection in immunocompromised children with cancer. The comprehensive search strategy followed the guidelines established by the Cochrane Handbook for Systematic Reviews of Interventions and the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) 2020 statement, and spanned multiple bibliographic databases and other public sources from January 1, 2012 to June 23, 2022. From 5188 records, 34 unique pediatric-focused studies met inclusion criteria. This review highlights the lack of published data on infectious disease testing in pediatric oncology patients, and the need for well-designed clinical impact and cost-effectiveness studies of both existing and novel diagnostic platforms. Such studies are necessary to optimize diagnostic and antimicrobial stewardship, leading to improvement in patient outcomes.

New and emerging options for management of invasive fungal diseases in paediatric patients

Invasive fungal diseases (IFDs) play an important role in the supportive care of paediatric patients with acute leukaemia and those undergoing allogeneic haematopoietic cell transplantation, and they are associated with significantly decreased overall survival rates in affected individuals. Relative to adults, children and adolescents are distinct in terms of host biology, predisposing conditions, presentation and epidemiology of fungal diseases, and in the pharmacology of antifungal agents. The paediatric development of antifungal agents has moved forward in a coordinated manner, and major advances have been made regarding concepts and recommendations for the prevention and treatment of IFDs. However, antifungal therapy is increasingly complex, and a solid knowledge of the available options is needed more than ever for successful management. This narrative review provides a summary of the paediatric development of agents that have been recently approved (anidulafungin, posaconazole) or are in advanced stages of development (isavuconazole). It also reviews the emerging evidence for the efficacy of echinocandins for prophylaxis of invasive aspergillosis, presents new data on alternative dosing regimens of echinocandins and voriconazole, and provides a brief overview of new antifungal agents in clinical development that are expected to be developed for paediatric patients.

Micafungin twice-a-week for prophylaxis of invasive Aspergillus infections in children with acute lymphoblastic leukaemia: A controlled cohort study

OBJECTIVES

Invasive Aspergillus infections during the early phase of childhood acute lymphoblastic leukemia (ALL) treatment come with morbidity and mortality. The interaction with vincristine hampers first-line azole prophylaxis. We describe the efficacy of an alternative twice-a-week micafungin regimen for Aspergillus prophylaxis.

METHODS

Newly diagnosed paediatric patients with ALL treated according to the ALL-11 protocol received micafungin twice-a-week (9 mg/kg/dose [max. 300 mg]) during the induction course (first 35 days of treatment) as part of routine care. A historical control cohort without Aspergillus prophylaxis was used. During the first consolidation course (day 36-79), standard itraconazole prophylaxis was used in both groups. The percentage of proven/probable Aspergillus infections during the induction/first consolidation course was compared between the cohorts. The cumulative incidence of proven/probable Aspergillus infections was estimated using a competing risk model. For safety evaluation, liver laboratory chemistry values were analysed.

RESULTS

A total of 169 and 643 paediatric patients with ALL were treated in the micafungin cohort (median age: 4 years [range 1-17]) and historical cohort (median age: 5 years [range 1-17]). The percentage of proven/probable Aspergillus infections was 1·2% (2/169) in the micafungin cohort versus 5·8% (37/643) in the historical cohort (p=0.013; Fisher's exact test). The differences in estimated cumulative incidence were assessed (p=0·014; Gray's test). Although significantly higher ALT/AST values were reported in the micafungin cohort, no clinically relevant side effects were observed.

CONCLUSIONS

Twice-a-week micafungin prophylaxis during the induction course significantly reduced the occurrence of proven/probable Aspergillus infections in the early phase of childhood ALL treatment.

The Austrian landscape of diagnostic capacity and access to treatment for invasive fungal infections

INTRODUCTION

Immunosuppression after chemotherapy, stem cell transplantation or solid organ transplantation are the main risk factors for invasive fungal infections in Austria. Here, we aim to describe the status of laboratory mycology and the access to antifungal treatment in Austria.

METHODS

Between October and November 2021, hospitals were contacted to participate in our online survey: www.clinicalsurveys.net/uc/IFI_management_capacity/. Centres were required to provide information on their institutional profile; self-assessment of burden of invasive fungal infections; access to microscopy, culture, serology, antigen detection and molecular testing; and availability of antifungal agents and therapeutic drug monitoring.

RESULTS

Responses were collected from university hospitals and laboratories in Graz, Innsbruck, Linz and Vienna. The four hospitals can provide tertiary care and were highly specialised, including management of patients with severe immunosuppression. All sites consider the incidence of invasive fungal infections to be moderate. Access to microscopy, culture, serology, antigen detection and molecular testing is provided regardless of laboratory. The maximum capacity to identify fungi varies from institution to institution. All currently marketed antifungal agents are available at the four sites.

CONCLUSION

Austria is currently well equipped to deal with the emerging threat of invasive fungal infections. However, hospitals may consider preparing for the potential endemicity of certain infections in the near future.

Pharmacokinetic investigations of isavuconazole in paediatric cancer patients show reduced exposure of isavuconazole after opening capsules for administration via a nasogastric tube

OBJECTIVES

To study the isavuconazole pharmacokinetics in a real-life paediatric cohort and confirm whether the isavuconazole exposures are within the adult exposure range. Furthermore, we are the first to describe unbound isavuconazole pharmacokinetics.

METHODS

In this prospective, observational study, the isavuconazole dosing regimen was as follows (IV/oral/nasogastric tube): 5.4 mg/kg isavuconazole (maximum 200 mg/dose) three times daily on Days 1 and 2, followed by 5.4 mg/kg isavuconazole (maximum 200 mg/dose) once daily. At least one pharmacokinetic curve was assessed. Non-linear mixed effects modelling was used for analysis. Monte Carlo simulations were performed with the above mentioned maintenance dose for IV administrations and a weight band dosing regimen for oral/nasogastric tube administrations: I) <18 kg (100 mg daily); II) 18-37 kg (150 mg daily); III)>37 kg (200 mg daily).

RESULTS

Seventeen paediatric patients with a median age of 9 years (range 1-17) and median weight of 26.0 kg (range 8.4-78.5) were evaluated. A two-compartment model describing linear pharmacokinetics of the unbound concentrations and saturable protein binding fitted the isavuconazole concentrations best. The absolute bioavailability of isavuconazole was 41.0% (95% CI: 32.4%-50.8%). The median (IQR) simulated exposures (AUC0-24h, SS) of the total isavuconazole concentrations after IV and oral/nasogastric tube administration were 87.7 mg·h/L (70.5-105.1) and 50.3 mg·h/L (39.0-62.4), respectively. The unbound isavuconazole fraction (unbound/total) ranged from 0.5% to 2.3%.

CONCLUSIONS

This study revealed low bioavailability after nasogastric tube administration with opened capsules. Isavuconazole exposures were in the expected range following IV administration. Total and unbound isavuconazole pharmacokinetics were reported with a 5-fold range in the unbound fraction.

Voriconazole plasma concentrations and dosing in paediatric patients below 24 months of age

Voriconazole (VCZ) is an important first-line option for management of invasive fungal diseases and approved in paediatric patients ≥24 months at distinct dosing schedules that consider different developmental stages. Information on dosing and exposures in children <24 months of age is scarce. Here we report our experience in children <24 months who received VCZ due to the lack of alternative treatment options. This retrospective analysis includes 50 distinct treatment episodes in 17 immunocompromised children aged between 3 and <24 months, who received VCZ between 2004 and 2022 as prophylaxis (14 patients; 47 episodes) or as empirical treatment (3 patients; 3 episodes) by mouth (46 episodes) or intravenously (4 episodes) based on contraindications, intolerance or lack of alternative options. Trough concentrations were measured as clinically indicated, and tolerability was assessed based on hepatic function parameters and discontinuations due to adverse events (AEs). VCZ was administered for a median duration of 10 days (range: 1-138). Intravenous doses ranged from 4.9 to 7.0 mg/kg (median: 6.5) twice daily, and oral doses from 3.8 to 29 mg/kg (median: 9.5) twice daily, respectively. The median trough concentration was 0.63 mg/L (range: 0.01-16.2; 38 samples). Only 34.2% of samples were in the recommended target range of 1-6 mg/L; 57.9% had lower and 7.9% higher trough concentrations. Hepatic function parameters analysed at baseline, during treatment and at end of treatment did not show significant changes during VCZ treatment. There was no correlation between dose and exposure or hepatic function parameters. In three episodes, VCZ was discontinued due to an AE (6%; three patients). In conclusion, this retrospective analysis reveals no signal for increased toxicity in paediatric patients <24 months of age. Empirical dosing resulted in mostly subtherapeutic exposures which emphasises the need for more systematic study of the pharmacokinetics of VCZ in this age group.

Access to the World Health Organization-recommended essential diagnostics for invasive fungal infections in critical care and cancer patients in Africa: A diagnostic survey

BACKGROUND

Invasive fungal infections (IFIs) contribute to significant morbidity and mortality among patients with haemato-oncological conditions, seriously ill hospitalised patients and those in intensive care (ICU). We surveyed for the World Health Organization-recommended essential diagnostic tests for IFIs in these risk groups in Africa.

METHODS

The Global Action For Fungal Infections (GAFFI) evaluated the different levels of access to both diagnostics for IFIs for populations in Africa, with the aim of building a comparative dataset and a publicly available interactive map. Data was collected through a validated questionnaire administered to a country leader in relevant topics (i.e., HIV, laboratory coordination) and/or Ministry of Health representatives and followed up with 2 rounds of validation by video calls, and later confirmation by email of findings.

RESULTS

Initial data was collected from 48 African countries covering 99.65 % of the population. Conventional diagnostics such as blood cultures, direct microscopy and histopathology were often used for diagnosis of IFIs in more than half of the facilities. Bronchoscopy was rarely done or not done in 20 countries (population 649 million). In over 40 African countries (population >850 million), Aspergillus antigen testing was never performed in either the public or private sectors. Computed tomography (CT) imaging is routinely used in 27 (56 %) of countries in the public sector and 21 44 %) in the private sector. However, magnetic resonance imaging remains relatively uncommon in most African countries.

CONCLUSIONS

There are critical gaps in the availability of essential diagnostics for IFIs in Africa, particularly Aspergillus antigen testing and modern medical imaging modalities. Early diagnosis and commencement of targeted therapy of IFIs are critical for optimal outcomes from complex cancer therapies.

The Challenge of Diagnosing Invasive Pulmonary Aspergillosis in Children: A Review of Existing and Emerging Tools

Invasive pulmonary aspergillosis remains a major cause of morbidity and mortality for immunocompromised children, particularly for patients with acute leukaemia and those undergoing haematopoietic stem cell transplantation. Timely diagnosis, using a combination of computed tomography (CT) imaging and microbiological testing, is key to improve prognosis, yet there are inherent challenges in this process. For CT imaging, changes in children are generally less specific than those reported in adults and recent data are limited. Respiratory sampling by either bronchoalveolar lavage or lung biopsy is recommended but is not always feasible in children, and serum biomarkers, including galactomannan, have important limitations. In this review we summarise the current paediatric data on available diagnostic tests for IPA and highlight key emerging diagnostic modalities with potential for future use.

Population pharmacokinetics of voriconazole and the role of CYP2C19 genotype on treatment optimization in pediatric patients

The aim of this study was to evaluate factors that impact on voriconazole (VRC) population pharmacokinetic (PPK) parameters and explore the optimal dosing regimen for different CYP2C19 genotypes in Chinese paediatric patients. PPK analysis was used to identify the factors contributing to the variability in VRC plasma trough concentrations. A total of 210 VRC trough concentrations from 91 paediatric patients were included in the study. The median VRC trough concentration was 1.23 mg/L (range, 0.02 to 8.58 mg/L). At the measurement of all the trough concentrations, the target range (1.0~5.5 mg/L) was achieved in 52.9% of the patients, while subtherapeutic and supratherapeutic concentrations were obtained in 40.9% and 6.2% of patients, respectively. VRC trough concentrations were adjusted for dose (Ctrough/D), with normal metabolizers (NMs) and intermediate metabolizers (IMs) having significantly lower levels than poor metabolizers (PMs) (PN-P < 0.001, PI-P = 0.039). A one-compartment model with first-order absorption and elimination was suitable to describe the VRC pharmacokinetic characteristics. The final model of VRC PPK analysis contained CYP2C19 phenotype as a significant covariate for clearance. Dose simulations suggested that a maintenance dose of 9 mg/kg orally or 8 mg/kg intravenously twice daily was appropriate for NMs to achieve the target concentration. A maintenance dose of 9 mg/kg orally or 5 mg/kg intravenously twice daily was appropriate for IMs. Meanwhile, PMs could use lower maintenance dose and an oral dose of 6 mg/kg twice daily or an intravenous dose of 5mg/kg twice daily was appropriate. To increase the probability of achieving the therapeutic range and improving efficacy, CYP2C19 phenotype can be used to predict VRC trough concentrations and guide dose adjustments in Chinese pediatric patients.

Therapeutic drug monitoring of voriconazole and CYP2C19 phenotype for dose optimization in paediatric patients

PURPOSE

The objective of this study was to evaluate factors influencing voriconazole (VRC) plasma trough concentrations and provide research data for optimizing VRC dosing in Chinese paediatric patients.

METHODS

Medical records of inpatients were reviewed retrospectively. Multivariate linear regression analysis was used to identify the factors contributing to the variability of VRC plasma trough concentrations.

RESULTS

A total of 250 VRC plasma trough concentrations from 131 paediatric patients were included in the analysis. The median VRC plasma trough concentration was 1.28 mg·L-1 (range, 0.02 to 9.69 mg·L-1). The target range was achieved in 51.6% of patients, while subtherapeutic and supratherapeutic concentrations were obtained in 40.4% and 8.0% of paediatric patients, respectively. The most commonly identified cytochrome P450 2C19 (CYP2C19) phenotype was intermediate metabolizers (IMs) (48.9%), followed by normal metabolizers (NMs) (40.5%) and poor metabolizers (PMs) (10.7%), but no ultrarapid metabolizers (UMs) were observed in our study. VRC plasma trough concentrations adjusted for dose (Cmin/D) were significantly lower in both NMs and IMs compared to PMs (PN-P < 0.001 and PI-P = 0.010, respectively). The dosage of VRC required to achieve the therapeutic range was related to age, with children aged < 6 years needing a significantly higher oral dose of VRC. The oral and intravenous maintenance doses needed to reach the therapeutic range were significantly lower than the recommended maintenance dose (P < 0.001, P < 0.001). Factors such as CYP2C19 polymorphisms, the combination of omeprazole, levels of albumin and alanine aminotransferase, were found to affect VRC exposure and explained some of the variability.

CONCLUSIONS

The VRC plasma trough concentration is significantly influenced by the CYP2C19 phenotype. The recommended maintenance dose for pediatric patients may not be appropriate for Chinese patients. To increase the probability of achieving the therapeutic range for VRC plasma trough concentration, the administration of VRC should consider the age of paediatric patients and the presence of CYP2C19 polymorphisms.

Therapeutic drug monitoring-guided dosing for pediatric cystic fibrosis patients: recent advances and future outlooks

INTRODUCTION

Medicine use in children with cystic fibrosis (CF) is complicated by inconsistent pharmacokinetics at variance with the general population, a lack of research into this and its effects on clinical outcomes. In the absence of established dose regimens, therapeutic drug monitoring (TDM) is a clinically relevant tool to optimize drug exposure and maximize therapeutic effect by the bedside. In clinical practice though, use of this is variable and limited by a lack of expert recommendations.

AREAS COVERED

We aimed to review the use of TDM in children with CF to summarize recent developments, current recommendations, and opportunities for future directions. We searched PubMed for relevant publications using the broad search terms "cystic fibrosis" in combination with the specific terms "therapeutic drug monitoring (TDM)" and "children." Further searches were undertaken using the name of identified drugs combined with the term "TDM."

EXPERT OPINION

Further research into the use of Bayesian forecasting and the relationship between exposure and response is required to personalize dosing, with the opportunity for the development of expert recommendations in children with CF. Use of noninvasive methods of TDM has the potential to improve accessibility to TDM in this cohort.

The Development and Validation of a Predictive Model for Voriconazole-Related Liver Injury in Hospitalized Patients in China

Voriconazole is widely used in the treatment and prevention of invasive fungal diseases. Common drug-induced liver injuries increase the economic burdens and the risks of premature drug withdrawal and disease recurrence. This study estimated the disposal cost of voriconazole-related liver injury, explored the risk factors of voriconazole-related liver injury in hospitalized patients, and established a predictive model of liver injury to assist clinicians and pharmacists in estimating the probability or risk of liver injury after voriconazole administration to allow for early identification and intervention in patients at high risk of liver injury. A retrospective study was conducted on the selected inpatients whose blood concentration of voriconazole was measured in the West China Hospital of Sichuan University from September 2016 to June 2020. The incidence and disposal cost of voriconazole-related liver injuries were calculated. The incidence of voriconazole-related liver injury was 15.82% (217/1372). The disposal cost has been converted to 2023 at a discount rate of 5%. The median (P₂₅, P₇₅) disposal cost of severe liver injury (n = 42), general liver injury (n = 175), and non-liver injury (n = 1155) was 993.59 (361.70, 1451.76) Chinese yuan, 0.00 (0.00, 410.48) yuan, and 0.00 (0.00, 0.00) yuan, respectively, with a statistically significant difference (p < 0.001). Single factor analysis and multiple factor logistic regression were used to analyze the risk factors of voriconazole-related liver injury. The voriconazole-related liver injury was related to the trough concentration (C_min, OR 1.099, 95% CI 1.058-1.140), hypoproteinemia (OR 1.723, 95% CI 1.126-2.636), and transplantation status (OR 0.555, 95% CI 0.325-0.948). The prediction model of liver injury was Logit (P)= -2.219 + 0.094 × C_min + 0.544 × H_{ydroproteinemia} - 0.589 × Transplantation, and the prediction model nomogram was established. The model validation results showed that the C-index of the derivation set and validation set was 0.706 and 0.733, respectively. The area under the curve (AUC) of the receiver operating characteristic (ROC) curve was 0.705 and 0.733, respectively, indicating that the model had good prediction ability. The prediction model will be helpful to develop clinical individualized medication of voriconazole and to identify and intervene in the cases of patients at high risk of voriconazole-related liver injury early on, in order to reduce the incidence of voriconazole-related liver injuries and the cost of treatment.

Changes in the epidemiology of invasive fungal disease in a Pediatric Hematology and Oncology Unit: the relevance of breakthrough infections

BACKGROUND

Invasive fungal disease (IFD) is a significant cause of morbimortality in children under chemotherapy or hematopoietic stem cell transplant (HSCT). The purpose of this study is to describe the changes in the IFD epidemiology that occurred in a Pediatric Hematology-Oncology Unit (PHOU) with an increasing activity over time.

METHODS

Retrospective revision of the medical records of children (from 6 months to 18 years old) diagnosed with IFD in the PHOU of a tertiary hospital in Madrid (Spain), between 2006 and 2019. IFD definitions were performed according to the EORTC revised criteria. Prevalence, epidemiological, diagnostic and therapeutic parameters were described. Comparative analyses were conducted using Chi-square, Mann-Whitney and Kruskal-Wallis tests, according to three time periods, the type of infection (yeast vs mold infections) and the outcome.

RESULTS

Twenty-eight episodes of IFD occurred in 27 out of 471 children at risk (50% males; median age of 9.8 years old, [IQR 4.9-15.1]), resulting in an overall global prevalence of 5.9%. Five episodes of candidemia and 23 bronchopulmonary mold diseases were registered. Six (21.4%), eight (28.6%) and 14 (50%) episodes met criteria for proven, probable and possible IFD, respectively. 71.4% of patients had a breakthrough infection, 28.6% required intensive care and 21.4% died during treatment. Over time, bronchopulmonary mold infections and breakthrough IFD increased (p=0.002 and p=0.012, respectively), occurring in children with more IFD host factors (p=0.028) and high-risk underlying disorders (p=0.012). A 64% increase in the number of admissions in the PHOU (p<0.001) and a 277% increase in the number of HSCT (p=0.008) were not followed by rising rates of mortality or IFD/1000 admissions (p=0.674).

CONCLUSIONS

In this study, we found that yeast infections decreased, while mold infections increased over time, being most of them breakthrough infections. These changes are probably related to the rising activity in our PHOU and an increase in the complexity of the baseline pathologies of patients. Fortunately, these facts were not followed by an increase in IFD prevalence or mortality rates.

Invasive Mold Infections in Children: Navigating Troubled Waters with a Broken Compass

Incidence of invasive mold infections in children, while rare, is increasing as the population of high-risk patients expands, including premature infants, pediatric patients undergoing treatment for hematological malignancies, or recipients of allogeneic hematologic stem cell transplants. The infectious agents, including Aspergillus spp., Mucorales, and other molds, are especially difficult to treat and have serious morbidity and high mortality. Clinicians must maintain a high index of suspicion for invasive mold infections in at-risk patients. Diagnosis of invasive mold infections is complicated by difficulties isolating pathogens on culture, but progress is being made in immunological and molecular diagnostic technologies. Treatment in children is challenging; no randomized controlled trials exist. There is a growing body of data on treatment, specifically on safer antifungal agents, including indications for treatment, spectrum of coverage, pharmacokinetics for different ages, and pharmacodynamic targets associated with therapeutic success. However, pediatricians must often extrapolate from adult data. In this review, we aim to harmonize the existing body of literature on invasive mold infections in children, covering epidemiology, clinical presentations, diagnostic methods, and principles of management.

A Practical Guide to Antifungal Susceptibility Testing

We review antifungal susceptibility testing and the development of clinical breakpoints, and detail an approach to using antifungal susceptibility results when breakpoints have not been defined. This information may prove helpful when selecting therapy for invasive fungal infections in children.

An Update on the Diagnosis and Treatment of Invasive Mold Disease of the Central Nervous System in Children

Epidemiological data of CNS IMD in pediatrics are limited. Aspergillus is the most frequently identified species, followed by other rare molds. Prompt diagnosis is of importance to define the optimal therapeutic management with respect to antifungal agent, dose, and evaluation of surgical intervention. The mortality rate of CNS IMD remains high. In this mini review we summarize the current knowledge on diagnosis and treatment of CNS IMD in pediatrics.

Mold-Active Antifungal Prophylaxis in Pediatric Patients with Cancer or Undergoing Hematopoietic Cell Transplantation

Invasive fungal diseases (IFDs), in particular invasive mold infections, still pose considerable problems in the care of children and adolescents treated for cancer or undergoing hematopoietic cell transplantation. As these infections are difficult to diagnose, and the outcomes for IFDs are still unsatisfactory, antifungal prophylaxis has become an important strategy in the clinical setting. Antifungal prophylaxis is indicated in patients at high risk for IFD, which is commonly defined as a natural incidence of at least 10%. As there is a growing interest in pediatric-specific clinical trials and pediatric-specific guidelines, this review focuses on the available data of mold-active antifungal prophylaxis in children and adolescents. The data demonstrate that a major effort is needed to characterize the pediatric patient population in which the net effect of prophylactic antifungals will be beneficial as well as to find the optimal prophylactic antifungal compound and dosage.

Immune signatures, testing, and management of febrile neutropenia in pediatric cancer patients

INTRODUCTION

Infectious complications, particularly invasive bacterial and fungal infections, are still a major cause of morbidity in pediatric cancer patients and are associated with significant mortality. Over the last few years, there has been much effort in defining risk groups to tailor antimicrobial therapy, and in establishing pediatric-specific guidelines for antimicrobial strategies.

AREAS COVERED

This review provides a critical overview of defining risk groups for infection, diagnostic work-up, antimicrobial prophylaxis, empirical therapy, and treatment of established infections.

EXPERT OPINION

To date, no generalizable risk prediction model has been established for pediatric cancer patients. There is growing interest in defining the impact of the individual genetic background on infectious complications. New diagnostic tools have been developed over the last few years, but they need to be validated in pediatric cancer patients. International, pediatric-specific guidelines for antimicrobial prophylaxis, empirical therapy, and treatment of established infections have recently been published and will harmonize antimicrobial strategies in the future.

Disseminated Cunninghamella elegans Infection Diagnosed by mNGS During Induction Therapy in a Child With Intermediate-risk Acute Lymphoblastic Leukemia: A Case Report and Review of Literature

We described a 14-year-old girl with acute lymphoblastic leukemia who developed disseminated mucormycosis during induction therapy. Disseminated Cunninghamella elegans infection was confirmed by histopathology, microbiological culture, and metagenomic next-generation sequencing analysis of skin tissue, blood, and cerebrospinal fluid. Subsequently, the patient received a combination of liposomal amphotericin B, posaconazole, and caspofungin for antifungal treatment, but eventually died because of severe fungal pneumonia, respiratory failure, and septic shock. Moreover, case reports of pulmonary mucormycosis in children published since 1959 were reviewed. In summary, metagenomic next-generation sequencing is an effective diagnostic method for Cunninghamella with high speed and sensitivity.

Serum Beta-D-Glucan in the Diagnosis of Invasive Fungal Disease in Neonates, Children and Adolescents: A Critical Analysis of Current Data

β-D-glucan (BDG) is a cell wall component of many pathogenic fungi. The detection of BDG as an assay is clinically broadly used as a diagnostic tool. However, the current data on BDG in paediatrics are limited, prompting specific considerations about when BDG can be used in neonates and children. We aimed to analyse the available data for the use of serum BDG in neonates and immunocompromised children and adolescents; as well as to understand the extent and characteristics of the use of BDG in children in Europe.

Pediatric Invasive Aspergillosis: A Retrospective Review of 59 Cases

Invasive aspergillosis (IA) is a major cause of morbidity and mortality. This study aimed to present our 10-year IA experience at a single center. Fifty-nine pediatric patients with IA were included in this study. The male-to-female ratio was 42/17. The median age was 8.75 years. Hematologic malignancy was present in the majority of the patients (40/59, 68%). The mean neutropenia duration was 18.5 days. Cytosine arabinoside was the most common immunosuppressive therapy directed at T cells during IA diagnosis. IA cases were categorized as proven (27%), probable (51%), or possible (22%) according to the 2008 European Organization for Research and Treatment of Cancer/Invasive Fungal Infections Cooperative Group and the National Institute of Allergy and Infectious Diseases Mycoses Study Group (EORTC/MSG) criteria. The lungs (78%) were the most common site of IA, and nodules were the most frequent radiological findings (75.5%). In 38 patients (64.4%) receiving antifungal prophylaxis, prophylactic agents included fluconazole (30.5%), liposomal amphotericin B (23.7%), posaconazole (8.5%), and voriconazole (1.7%). Initial treatment was most commonly administered as monotherapy (69.5%). The median antifungal treatment duration was 67 days. Eleven deaths (18.6%) were due to aspergillosis. With the increased use of corticosteroids, biological agents, and intensive immunosuppressive chemotherapy, IA will most likely continue to occur frequently in pediatric patients.

Liposomal amphotericin B-the present

Most invasive fungal infections are opportunistic in nature but the epidemiology is constantly changing, with new risk groups being identified. Neutropenia is a classical risk factor for fungal infections, while critically ill patients in the ICU are now increasingly at risk of yeast and mould infections. Factors to be considered when choosing antifungal treatment include the emergence of rarer fungal pathogens, the risk of resistance to azoles and echinocandins and the possibility of drug-drug interactions. Liposomal amphotericin B has retained its place in the therapeutic armamentarium based on its clinical profile: a broad spectrum of antifungal activity with a low risk of resistance, predictable pharmacokinetics with a rapid accumulation at the infection site (including biofilms), a low potential for drug-drug interactions and a low risk of acute and chronic treatment-limiting toxicities versus other formulations of amphotericin B. It is a suitable choice for the first-line empirical or pre-emptive treatment of suspected fungal infections in neutropenic haematology patients and is an excellent alternative for patients with documented fungal disease who can no longer tolerate or continue their first-line azole or echinocandin therapy, both in the haematology setting and in the ICU. Moreover, it is the first-line drug of choice for the treatment of invasive mucormycosis. Finally, liposomal amphotericin B is one of the few antifungal agents approved for use in children of all ages over 1 month and is included in paediatric-specific guidelines for the management of fungal disease.

Liposomal amphotericin B-the past

The discovery of amphotericin B, a polyene antifungal compound, in the 1950s, and the formulation of this compound in a liposomal drug delivery system, has resulted in decades of use in systemic fungal infections. The use of liposomal amphotericin B formulation is referenced in many international guidelines for the treatment of fungal infections such as Aspergillus and cryptococcal disease and Candida infections, as well as other less common infections such as visceral leishmaniasis. With the development of liposomal amphotericin B, an improved therapeutic index could be achieved that allowed the attainment of higher drug concentrations in both the plasma and tissue while simultaneously lowering the toxicity compared with amphotericin B deoxycholate. In over 30 years of experience with this drug, a vast amount of information has been collected on preclinical and clinical efficacy against a wide variety of pathogens, as well as evidence on its toxicity. This article explores the history and nature of the liposomal formulation, the key clinical studies that developed the pharmacokinetic, safety and efficacy profile of the liposomal formulation, and the available microbiological data.

Recurrent massive hemoptysis from distal pulmonary pseudoaneurysms complicating invasive aspergillosis in a teenager

Invasive pulmonary aspergillosis in children rarely complicates life-threatening massive hemoptysis. Here, we report the case of a 15-year-old girl with acute lymphoblastic leukemia who was hospitalized for fever and medullary aplasia 1 month after beginning chemotherapy for invasive pulmonary aspergillosis. Despite voriconazole and caspofungine treatment, excavation of some lesions caused a unilateral small pneumothorax and bilateral pleural effusion, justifying intensive care management. The massive hemoptysis that occurred on day 23 was complicated with heart failure, and the patient was promptly resuscitated. Fibroscopy and computed tomography angiography (CTA) did not reveal the origin or cause of the bleeding. A second massive bleeding event occurred on day 32, and heart failure resolved after 10min of low flow. A new CTA showed 2 pseudoaneurysms of the subsegmental pulmonary arteries that were treated with embolization. Sedation was gradually decreased owing to improvement in respiratory status, but the patient did not regain consciousness because of deep brain sequelae. A limitation of care was decided upon, and the patient died in the following weeks. Massive hemoptysis is a rare life-threatening complication of invasive pulmonary aspergillosis, especially in children. Pulmonary artery pseudoaneurysms are unusual and should be detected as soon as possible to guide therapy. Intensive care management should be followed by embolization if the patient is stable; otherwise, surgery is indicated, ideally after identifying the source of bleeding by CTA or bronchoscopy. Early CTA follow-up can be proposed if the source of bleeding is still unknown as pseudoaneurysms can appear or grow rapidly.

Microdialysis of Drug and Drug Metabolite: a Comprehensive In Vitro Analysis for Voriconazole and Voriconazole N-oxide

Purpose

Voriconazole is a therapeutically challenging antifungal drug associated with high interindividual pharmacokinetic variability. As a prerequisite to performing clinical trials using the minimally-invasive sampling technique microdialysis, a comprehensive in vitro microdialysis characterization of voriconazole (VRC) and its potentially toxic N-oxide metabolite (NO) was performed.

Methods

The feasibility of simultaneous microdialysis of VRC and NO was explored in vitro by investigating the relative recovery (RR) of both compounds in the absence and presence of the other. The dependency of RR on compound combination, concentration, microdialysis catheter and study day was evaluated and quantified by linear mixed-effects modeling.

Results

Median RR of VRC and NO during individual microdialysis were high (87.6% and 91.1%). During simultaneous microdialysis of VRC and NO, median RR did not change (87.9% and 91.1%). The linear mixed-effects model confirmed the absence of significant differences between RR of VRC and NO during individual and simultaneous microdialysis as well as between the two compounds (p > 0.05). No concentration dependency of RR was found (p = 0.284). The study day was the main source of variability (46.3%) while the microdialysis catheter only had a minor effect (4.33%). VRC retrodialysis proved feasible as catheter calibration for both compounds.

Conclusion

These in vitro microdialysis results encourage the application of microdialysis in clinical trials to assess target-site concentrations of VRC and NO. This can support the generation of a coherent understanding of VRC pharmacokinetics and its sources of variability. Ultimately, a better understanding of human VRC pharmacokinetics might contribute to the development of personalized dosing strategies.

Novel Insights into Fungal Infections Prophylaxis and Treatment in Pediatric Patients with Cancer

Invasive fungal diseases (IFDs) are a relevant cause of morbidity and mortality in children with cancer. Their correct prevention and management impact patients’ outcomes. The aim of this review is to highlight the rationale and novel insights into antifungal prophylaxis and treatment in pediatric patients with oncological and hematological diseases. The literature analysis showed that IFDs represent a minority of cases in comparison to bacterial and viral infections, but their impact might be far more serious, especially when prolonged antifungal therapy or invasive surgical treatments are required to eradicate colonization. A personalized approach is recommended since pediatric patients with cancer often present with different complications and require tailored therapy. Moreover, while the Aspergillus infection rate does not seem to increase, in the near future, new therapeutic recommendations should be required in light of new epidemiological data on Candidemia due to resistant species. Finally, further studies on CAR-T treatment and other immunotherapies are needed in patients with unique needs and the risk of complications. Definitive guidelines on IFD treatment considering the evolving epidemiology of antifungal resistance, new therapeutic approaches in pediatric cancer, novel antifungal drugs and the importance of an appropriate antifungal stewardship are urgently needed.

Antibiotic-induced depletion of Clostridium species increases the risk of secondary fungal infections in preterm infants

Preterm infants or those with low birth weight are highly susceptible to invasive fungal disease (IFD) and other microbial or viral infection due to immaturity of their immune system. Antibiotics are routinely administered in these vulnerable infants in treatment of sepsis and other infectious diseases, which might cause perturbation of gut microbiome and hence development of IFD. In this study, we compared clinical characteristics of fungal infection after antibiotic treatment in preterm infants. As determined by 16S rRNA sequencing, compared with non-IFD patients with or without antibiotics treatment, Clostridium species in the intestinal tracts of patients with IFD were almost completely eliminated, and Enterococcus were increased. We established a rat model of IFD by intraperitoneal inoculation of C. albicans in rats pretreated with meropenem and vancomycin. After pretreatment with antibiotics, the intestinal microbiomes of rats infected with C. albicans were disordered, as characterized by an increase of proinflammatory conditional pathogens and a sharp decrease of Clostridium species and Bacteroides. Immunofluorescence analysis showed that C. albicans-infected rats pretreated with antibiotics were deficient in IgA and IL10, while the number of Pro-inflammatory CD11c⁺ macrophages was increased. In conclusion, excessive use of antibiotics promoted the imbalance of intestinal microbiome, especially sharp decreases of short-chain fatty acids (SCFA)-producing Clostridium species, which exacerbated the symptoms of IFD, potentially through decreased mucosal immunomodulatory molecules. Our results suggest that inappropriate use of broad-spectrum antibiotics may promote the colonization of invasive fungi. The results of this study provide new insights into the prevention of IFD in preterm infants.

Challenges in the Treatment of Invasive Aspergillosis in Immunocompromised Children

Invasive aspergillosis (IA) is associated with significant morbidity and mortality. Voriconazole remains the drug of choice for the treatment of IA in children; however, the complex kinetics of voriconazole in children make dosing challenging and therapeutic drug monitoring (TDM) essential for treatment success. The overarching goal of this review is to discuss the role of voriconazole, posaconazole, isavuconazole, liposomal amphotericin B, echinocandins, and combination antifungal therapy for the treatment of IA in children. We also provide a detailed discussion of antifungal TDM in children.

Isavuconazole for COVID-19-Associated Invasive Mold Infections

Isavuconazole is a broad-spectrum antifungal drug recently approved as a first-line treatment for invasive aspergillosis and as a first or alternative treatment for mucormycosis. The purpose of this review was to report and discuss the use of isavuconazole for the treatment of COVID-19-associated aspergillosis (CAPA), and COVID-19-associated mucormycosis (CAM). Among all studies which reported treatment of CAPA, approximately 10% of patients were reportedly treated with isavuconazole. Considering 14 identified studies that reported the use of isavuconazole for CAPA, isavuconazole was used in 40% of patients (95 of 235 treated patients), being first-line monotherapy in over half of them. We identified six studies that reported isavuconazole use in CAM, either alone or in combination therapy. Overall, isavuconazole was used as therapy in 13% of treated CAM patients, frequently as combination or sequential therapy. The use of isavuconazole in CAPA and CAM is complicated by the challenge of achieving adequate exposure in COVID-19 patients who are frequently obese and hospitalized in the ICU with concomitant renal replacement therapy (RRT) or extracorporeal membrane oxygenation (ECMO). The presence of data on high efficacy in the treatment of aspergillosis, lower potential for drug–drug interactions (DDIs) and for subtherapeutic levels, and no risk of QT prolongation compared to other mold-active azoles, better safety profile than voriconazole, and the possibility of using an intravenous formulation in the case of renal failure are the advantages of using isavuconazole in this setting.

Pharmacogenetic Analysis of Voriconazole Treatment in Children

Voriconazole is among the first-line antifungal drugs to treat invasive fungal infections in children and known for its pronounced inter- and intraindividual pharmacokinetic variability. Polymorphisms in genes involved in the metabolism and transport of voriconazole are thought to influence serum concentrations and eventually the therapeutic outcome. To investigate the impact of these genetic variants and other covariates on voriconazole trough concentrations, we performed a retrospective data analysis, where we used medication data from 36 children suffering from invasive fungal infections treated with voriconazole. Data were extracted from clinical information systems with the new infrastructure SwissPK^cdw, and linear mixed effects modelling was performed using R. Samples from 23 children were available for DNA extraction, from which 12 selected polymorphism were genotyped by real-time PCR. 192 (49.1%) of 391 trough serum concentrations measured were outside the recommended range. Voriconazole trough concentrations were influenced by polymorphisms within the metabolizing enzymes CYP2C19 and CYP3A4, and within the drug transporters ABCC2 and ABCG2, as well as by the co-medications ciprofloxacin, levetiracetam, and propranolol. In order to prescribe an optimal drug dosage, pre-emptive pharmacogenetic testing and careful consideration of co-medications in addition to therapeutic drug monitoring might improve voriconazole treatment outcome of children with invasive fungal infections.

Effects of CYP2C19, CYP2C9 and CYP3A4 gene polymorphisms on plasma voriconazole levels in Chinese pediatric patients

OBJECTIVES

Voriconazole is the most commonly used antifungal agent in clinical application. Previous studies suggested that voriconazole was extensively metabolized by CYP450 enzyme system, including CYP2C19, CYP2C9 and CYP3A4, which contributed to the individual variability of the pharmacokinetic process of voriconazole. This study aimed to investigate the effects of CYP2C19, CYP2C9 and CYP3A4 gene polymorphisms on plasma voriconazole concentrations in Chinese pediatric patients.

METHODS

This study prospectively evaluated pediatric patients administrating voriconazole for the treatment or prophylaxis of invasive fungal infections from October 2018 to July 2020. Seven single-nucleotide polymorphisms in CYP2C19 (CYP2C19*2, CYP2C19*3, and CYP2C19*17), CYP2C9 (CYP2C9*3, CYP2C9*13) and CYP3A4 (CYP3A4*22, rs4646437) were detected by real-time fluorescent PCR with TaqMan probes. The voriconazole trough plasma concentration was determined by UPLC-MS/MS.

RESULTS

A total of 68 pediatric patients were enrolled in this study. Our results showed that voriconazole plasma concentrations of patients with CYP2C19*2 or CYP2C19*3 allele were significantly higher than that with wild-type carriers (P < 0.0001, P = 0.004, respectively). However, CYP2C9*3 and CYP3A4 rs4646437 were not significantly associated with voriconazole plasma levels. The CYP2C19*17, CYP2C9*13 and CYP3A4*22 alleles were not observed in our study. Additionally, multiple linear regression analysis indicated that CYP2C19*2 and CYP2C19*3 alleles remained predictors of voriconazole plasma concentration (r2 = 0.428; P < 0.0001). For CYP2C19 metabolizer phenotype, trough concentration of voriconazole was significantly lower in NM group compared with IM (P < 0.0001) and PM (P = 0.004) groups.

CONCLUSION

Voriconazole plasma levels in pediatric patients are mainly affected by CYP2C19 gene polymorphisms.

Clinical and Microbiological Characteristics of Neonates with Candidemia and Impacts of Therapeutic Strategies on the Outcomes

Neonatal candidemia is associated with significant morbidities and a high mortality rate. We aimed to investigate the clinical characteristics of Candida bloodstream infections in neonates and the impact of therapeutic strategies on the outcomes. We identified all the neonates with candidemia from a medical center in Taiwan over an 18-year period (2003−2021) and analyzed them. Clinical isolates were confirmed by DNA sequencing, and antifungal susceptibility testing was performed. The prognostic factors associated with clinical treatment failure (30-day, all-cause mortality and persistent candidemia > 72 h after antifungal agents) and in-hospital mortality were analyzed using logistic regression modeling. A total of 123 neonates with 139 episodes of candidemia were included in the study. The median (IQR) gestational age and birth weight of the neonates with candidemia were 29.0 (26.0−35.0) weeks and 1104.0 (762.0−2055) g, respectively. The most common Candida spp. was Candida albicans (n = 57, 41.0%), followed by C. parapsilosis (n = 44, 31.7%), Candida guilliermondii (n = 12, 8.6%), and C. glabrata (n = 11, 7.9%). The overall susceptibility to fluconazole was 81.3%, and the resistant rates against other antifungal agents were less than 3%. The cumulative mortality rate at 7 and 30 days after the first episode of candidemia was 11.3% and 32.3%, respectively. The overall in-hospital mortality rate was 42.3%. The treatment outcomes did not change over the study period and were not affected by delayed initiation of antifungal agents. Multivariate analysis showed that delayed catheter removal (odds ratio [OR], 5.54; 95% confidence interval [CI]: 1.93−15.86, p = 0.001), septic shock (OR, 7.88; 95% CI: 2.83−21.93, p < 0.001), and multiple chronic comorbidities (OR, 8.71; 95% CI: 1.82−41.81, p = 0.007) were independently associated with the final in-hospital mortality. We concluded that the overall mortality of neonatal candidemia has remained consistently high over the past decade. Prompt early catheter removal and an aggressive treatment strategy for neonatal candidemia with septic shock would be critical to improving patient outcomes.

Molds and More: Rare Fungal Infections in Preterm Infants <24 Weeks of Gestation

BACKGROUND

Extreme immature infants are at an increased risk of fungal infection due to immaturity of the skin barrier and the immune system. Besides Candida infections, in particular, Aspergillus may cause life-threatening diseases in preterm infants. Frequently, Aspergillus primarily affects the skin and may cause extensive damage.

METHODS

We searched our hospital database for fungal infections other than Candida in preterm infants treated between 2015 and 2020 at our level III neonatal intensive care unit of the University Hospital of Cologne.

RESULTS

In total, 13 preterm infants were identified. Of these, 11 had cutaneous Aspergillosis, one infant had severe enterocolitis caused by Aspergillus and Rhizopus and one had invasive intraabdominal Trichosporon mucoides infection. All infants were born <24 weeks of gestation, were delivered due to premature labor or chorioamnionitis, and had received prenatal steroids and/or hydrocortisone. Voriconazole and liposomal Amphotericin B were first-line treatments and the length of treatment varied between 3 and 148 days. Two infants died associated with severe infection. Liver toxicity was observed in six infants treated with Voriconazole. Therapeutic drug management for Voriconazole was performed in four infants. Target levels were not achieved by the doses that are recommended.

CONCLUSIONS

Rare fungal infections, predominantly cutaneous Aspergillosis affects the most immature preterm infants and may cause severe disease. Treatment with Voriconazole has a high rate of liver toxicity and target levels are difficult to achieve in extremely immature infants.