Prospective Aspergillus galactomannan antigen testing in pediatric hematopoietic stem cell transplant recipients

Fungal diagnostic testing and therapy: navigating the neutropenic period in children with high-risk leukemia

Children, adolescents, and young adults receiving intensive chemotherapy for acute myeloid leukemia or high-risk or relapsed acute lymphoblastic leukemia sustain prolonged periods of neutropenia that predispose them to invasive fungal disease (IFD). For many decades the standard of care for these patients was to initiate empirical antifungal therapy after a period of prolonged fever and neutropenia. Recent publications have yielded important evidence on the utility of different diagnostic and therapeutic approaches aimed at reducing the impact of IFD among these patients during these vulnerable periods. This case-based review highlights and interprets the published data to provide context for the IFD diagnostic and therapeutic recommendations proposed in multiple published guidelines. Personalized approaches are offered at points where evidence is lacking. Time points where specific knowledge gaps exist are identified along the clinical trajectory of the prolonged neutropenic period to illustrate areas for future investigation.

The role of galactomannan test results in the diagnosis of pediatric invasive aspergillosis

BACKGROUND

Invasive aspergillosis (IA) is an important cause of morbidity and mortality in immunosuppressed children. Early detection of the infection can improve prognosis in this patient population.

OBJECTIVES

To investigate the utility of Aspergillus galactomannan antigen assay (GM-EIA) as a diagnostic tool for IA in at-risk paediatric patients.

PATIENTS/METHODS

For the study, 659 GM-EIA results from 59 patients diagnosed with IA and 3368 GM-EIA results from 351 subjects without evidence for IA (controls) were reviewed retrospectively. Three cut-off values (i.e. ≥0.5, ≥1, ≥1.5) were specified to determine GM-EIA positivity.

RESULTS

The median age was 6.3 years for boys and 14.5 years for girls. There was a significant difference between the girls and boys in terms of age (p < 0.01). For proven/probable/possible IA patients, sensitivity of 67.8% and specificity of 59.8% were detected when the ≥0.5 cut-off value was used for GM-EIA-positivity. The specificity increased to 80% at the cut-off of ≥1 and to 88% at the cut-off of ≥1.5. False positivity rates were 9.14, 3, and 1.45% at the ≥0.5, ≥1 and ≥1.5 cut-offs respectively. In the proven/probable IA group, sensitivity and negative predictive values were 86.9 and 97.2% at the ≥0.5 cut-off, 85.7 and 97.9%, at the ≥1 cut-off and 84.2 and 98.1% at ≥1.5 cut-off respectively. The positive likelihood ratio was 7.57 and the odds ratio was 42.67 at ≥1.5 cut-off.

CONCLUSION

The GM-EIA may be used for both screening and diagnostic purposes in paediatric patients using a cut-off value of ≥1.5 for GM-EIA positivity.

Metagenomic Next-Generation Sequencing versus Traditional Pathogen Detection in the Diagnosis of Peripheral Pulmonary Infectious Lesions

Purpose

The aim of this study was to evaluate the value of metagenomic next-generation sequencing (mNGS) in peripheral pulmonary infection management by comparing the diagnostic yield of mNGS and traditional pathogen detection methods on interventional specimens obtained by bronchoscopy.

Patients and Methods

This study enrolled patients suspected with pulmonary infection who were admitted to Tianjin Medical University General Hospital from June 2018 to August 2019. Specimens were obtained from bronchoscopy for mNGS analysis and traditional pathogen detection (including bronchoalveolar lavage fluid microbial culture, smear microscopy, and lung biopsy histopathology), and the diagnostic yields were compared between mNGS and traditional methods to evaluate the diagnostic value of mNGS in peripheral pulmonary infection diagnosis.

Results

In this study, by comparing mNGS with traditional pathogen detection, the results indicated that, first, mNGS identified at least one microbial species in almost 89% of the patients with pulmonary infection; second, mNGS detected microbes related to human diseases in 94.49% of samples from pulmonary infection patients who had received negative results from traditional pathogen detection; third, the accuracy and sensitivity of mNGS are higher than those of traditional pathogen detection; and, finally, mNGS could simultaneously detect and identify a large variety of pathogens.

Conclusion

Metagenomic NGS analysis provided fast and precise pathogen detection and identification, contributing to prompt and accurate treatment of peripheral pulmonary infection.

Diagnosis of invasive fungal disease in children: a narrative review

Introduction: Invasive fungal diseases (IFD) represent important causes of morbidity and mortality in pediatrics. Early diagnosis and treatment of IFD is associated with better outcome and this entails the need to use fast and highly sensitive and specific methods that can support clinicians in the management of IFD.Areas covered: A narrative review was performed on conventional diagnostic methods such as culture, microscopy and histopathology are still gold standard but are burdened by a lack of sensitivity and specificity; on the other hand, imaging and noninvasive antigen-based such as beta-D-glucan, galactomannan and molecular biomarkers are the most convenient nonculture methods for diagnosis and monitoring effects of therapy. Aim of the present review is to summarize what is available in these fields at end of the second decade of the third millennium and look for future perspectives.Expert opinion: Promising and useful diagnostic methods have been applied in infectious disease diagnosis in clinical practice or in designing platforms. Unfortunately, most of them are not standardized or validated in pediatric population. However, clinicians should be aware of all innovative diagnostic tools to use in combination with conventional diagnostic methods for a better management of pathology and patient.

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

SCOPE

Presenting symptoms, distributions and patterns of diseases and vulnerability to invasive aspergillosis (IA) are similar between children and adults. However, differences exist in the epidemiology and underlying conditions, the usefulness of newer diagnostic tools, the pharmacology of antifungal agents and in the evidence from interventional phase 3 clinical trials. Therefore, the European Society for Clinical Microbiology and Infectious Diseases (ESCMID) and the European Confederation of Medical Mycology (ECMM) have developed a paediatric-specific guideline for the diagnosis and management of IA in neonates and children.

METHODS

Review and discussion of the scientific literature and grading of the available quality of evidence was performed by the paediatric subgroup of the ESCMID-ECMM-European Respiratory Society (ERS) Aspergillus disease guideline working group, which was assigned the mandate for the development of neonatal- and paediatric-specific recommendations.

QUESTIONS

Questions addressed by the guideline included the epidemiology of IA in neonates and children; which paediatric patients may benefit from antifungal prophylaxis; how to diagnose IA in neonates and children; which antifungal agents are available for use in neonates and children; which antifungal agents are suitable for prophylaxis and treatment of IA in neonates and children; what is the role of therapeutic drug monitoring of azole antifungals; and which management strategies are suitable to be used in paediatric patients. This guideline provides recommendations for the diagnosis, prevention and treatment of IA in the paediatric population, including neonates. The aim of this guideline is to facilitate optimal management of neonates and children at risk for or diagnosed with IA.

Invasive Aspergillosis in Children: Update on Current Guidelines

Invasive aspergillosis (IA) is an important cause of infectious morbidity and mortality in immunocompromised paediatric patients. Despite improvements in diagnosis, prevention, and treatment, IA is still associated with high mortality rates. To address this issue, several international societies and organisations have proposed guidelines for the management of IA in the paediatric population. In this article, we review current recommendations of the Infectious Diseases Society of America, the European Conference on Infection in Leukaemia and the European Society of Clinical Microbiology and Infectious Diseases for the management and prevention of IA in children.

Diagnosis and management of Aspergillus diseases: executive summary of the 2017 ESCMID-ECMM-ERS guideline

The European Society for Clinical Microbiology and Infectious Diseases, the European Confederation of Medical Mycology and the European Respiratory Society Joint Clinical Guidelines focus on diagnosis and management of aspergillosis. Of the numerous recommendations, a few are summarized here. Chest computed tomography as well as bronchoscopy with bronchoalveolar lavage (BAL) in patients with suspicion of pulmonary invasive aspergillosis (IA) are strongly recommended. For diagnosis, direct microscopy, preferably using optical brighteners, histopathology and culture are strongly recommended. Serum and BAL galactomannan measures are recommended as markers for the diagnosis of IA. PCR should be considered in conjunction with other diagnostic tests. Pathogen identification to species complex level is strongly recommended for all clinically relevant Aspergillus isolates; antifungal susceptibility testing should be performed in patients with invasive disease in regions with resistance found in contemporary surveillance programmes. Isavuconazole and voriconazole are the preferred agents for first-line treatment of pulmonary IA, whereas liposomal amphotericin B is moderately supported. Combinations of antifungals as primary treatment options are not recommended. Therapeutic drug monitoring is strongly recommended for patients receiving posaconazole suspension or any form of voriconazole for IA treatment, and in refractory disease, where a personalized approach considering reversal of predisposing factors, switching drug class and surgical intervention is also strongly recommended. Primary prophylaxis with posaconazole is strongly recommended in patients with acute myelogenous leukaemia or myelodysplastic syndrome receiving induction chemotherapy. Secondary prophylaxis is strongly recommended in high-risk patients. We strongly recommend treatment duration based on clinical improvement, degree of immunosuppression and response on imaging.

Serum galactomannan for diagnosing invasive aspergillosis in pediatric patients: A meta-analysis

BACKGROUND

The serum galactomannan (GM) assay is used to diagnose invasive aspergillosis (IA). We conducted a systematic review and analysis to estimate the overall accuracy of the serum GM test for diagnosing pediatric IA.

METHOD

A systematic literature review was conducted of all relevant studies published in PubMed and EMbase databases up to March 10, 2017. We selected and assessed articles that reported diagnostic data related to serum GM for diagnosis of pediatric IA. Pooled diagnostic odds ratios (DORs) and summary receiver operating characteristics (SROCs) were constructed with a cutoff value of 0.5. Additionally, pooled sensitivity (SEN), specificity (SPE), and positive and negative likelihood ratios (PLR and NLR, respectively) were estimated for summarizing overall test performance.

RESULTS

Seventeen studies were included in this systematic review. The total number of patients (age range 0-21 years old) was 1768, with 178 that had proven or probable IA. The pooled serum GM assay results, with a cutoff value of 0.5 for proven or probable IA, were DOR: 41.16 (95% confidence interval (CI) 21.48-78.86), SEN: 0.85 (95% CI 0.72-0.93), SPE: 0.88 (95% CI 0.80-0.93), PLR: 6.92 (95% CI 4.40-10.88), and NLR: 0.17 (95% CI 0.09-0.32). The SROC was 0.93.

CONCLUSION

Serum GM can be used to assist in diagnosis of proven or probable pediatric IA. However, serum GM test results should be interpreted in combination with clinical findings in pediatric IA cases, as the test results are not always sensitive or specific enough for pediatric IA.

Role of Molecular Biomarkers in the Diagnosis of Invasive Fungal Diseases in Children

Invasive fungal diseases are important clinical problems that are often complicated by severe illness and therefore the inability to use invasive measures to definitively diagnose the disease. Tests for a range of fungal biomarkers that do not require an invasive sample-collection procedure have been incorporated into adult clinical practice, but pediatric data and pediatric-specific recommendations for some of these diagnostic tools are lacking. In this review, we summarize the published literature and contemporary strategies for using the biomarkers galactomannan, (1→3)-β-d-glucan, Candida mannan antigen and anti-mannan antibody, and fungal polymerase chain reaction for diagnosing invasive fungal disease in children. Data on biomarker use in neonates and children with cancer, history of hematopoietic stem cell transplant, or primary immunodeficiency are included. Fungal biomarker tests performed on blood, other body fluids, or tissue specimens represent promising adjuncts to the diagnostic armamentarium in populations with a high prevalence of invasive fungal disease, but substantial gaps exist in the correct use and interpretation of these diagnostic tools in pediatric patients.

Progress in the Diagnosis of Invasive Fungal Disease in Children

PURPOSE OF REVIEW

This review summarizes the fungal diagnostic measures currently available for use in paediatric patients at high risk for developing invasive fungal disease (IFD) and those suspected of having an IFD. The clinical utility of each test is described based on reported performances of individual tests in specific paediatric populations.

RECENT FINDINGS

Available studies in the paediatric population are scarce and are characterized by a huge heterogeneity in underlying diseases (e.g. different risk for IFD), different study objectives and management strategies (screening versus diagnostic) used.

SUMMARY

A final valuation of paediatric studies on fungal diagnostic tools is limited. While the galactomannan and fungal PCR assays are useful to exclude the presence of IFD, it is unclear if mannan, mannan antibodies and β-D-glucan are of benefit due to a lack of studies or validation of the cut-off, respectively. Well-designed multicentre paediatric studies are urgently needed to improve the outcome of IFD.

Galactomannan, β-D-Glucan, and Polymerase Chain Reaction-Based Assays for the Diagnosis of Invasive Fungal Disease in Pediatric Cancer and Hematopoietic Stem Cell Transplantation: A Systematic Review and Meta-Analysis

We systematically reviewed and analyzed the available data for galactomannan (GM), β-D-glucan (BG), and polymerase chain reaction (PCR)-based assays to detect invasive fungal disease (IFD) in patients with pediatric cancer or undergoing hematopoietic stem cell transplantation when used as screening tools during immunosuppression or as diagnostic tests in patients presenting with symptoms such as fever during neutropenia (FN). Of 1532 studies screened, 25 studies reported on GM (n = 19), BG (n = 3), and PCR (n = 11). All fungal biomarkers demonstrated highly variable sensitivity, specificity, and positive predictive values, and these were generally poor in both clinical settings. GM negative predictive values were high, ranging from 85% to 100% for screening and 70% to 100% in the diagnostic setting, but failure to identify non-Aspergillus molds limits its usefulness. Future work could focus on the usefulness of combinations of fungal biomarkers in pediatric cancer and HSCT.

Diagnosis of invasive fungal diseases in pediatric patients

INTRODUCTION

The optimal management of invasive fungal infections (IFIs) in children requires prompt and precise diagnosis that enables timely implementation of appropriate antifungal therapy and decreased use of unnecessary toxic antifungals. Areas covered: Traditional approaches such as culture, microscopy and histopathology remain the gold standard but are often not sufficiently sensitive and specific. These limitations have led to the development of alternative non-invasive diagnostic methods that in most cases detect fungal components, such as antigens or nucleic acids. To date, galactomannan and 1,3 β-D-glucan assays are the most efficient non-culture methods for diagnosis and monitoring of antifungal therapy. New technologies from nano-sciences are applied, like T2Candida assay. However, these are not standardized or validated in children. Herein, we focus on IFI diagnosis emphasizing current perspectives, interpretation difficulties, and need for further evaluation in pediatrics. Expert commentary: The new diagnostic tools may enhance diagnostic capacity in combination with traditional methods.

Diagnostic Values and Limitations of (1,3)-β-D-Glucans and Galactomannan Assays for Invasive Fungal Infection in Patients Admitted to Pediatric Intensive Care Unit

The relationship among (1,3)-β-D-glucans (BG), galactomannan (GM), and the risk of developing invasive fungal infections (IFI) has been observed in adult ICU and in children with hematological malignancies. Only scant data evaluated the value of BG/GM assays for diagnosis of IFI in patients with nonhematological diseases in pediatric intensive care unit (PICU). In this study, we assessed the diagnostic value of these markers for IFI in PICU. The records of 230 patients were retrospectively evaluated. Out of 117 patients (7 proven, 23 probable, and 87 cases without evidence of IFI) performed GM and BG assays. The results showed many factors were associated with false-positive test results. Patients who aged over 3 years had higher levels of GM and BG than younger infants. The levels of BG were higher in subjects with dairy, human blood products, antibiotics, and corticosteroids therapy than in cases without these treatments. Unlike BG assay, GM assay was less susceptible to above-mentioned factors expect blood products. The levels of BG and GM in IFI cases were dramatically higher than in controls. The diagnostic performance of these assays showed that GM assay had better results when compared with BG assay. On the whole, negative predictive value in both GM and BG assays was dramatically higher than other diagnostic parameters. In conclusion, BG assay was highly susceptible to many factors, and GM assay could be useful for diagnosis of IFI for its high sensitivity, but the over benefit of this assay limited in its inadequate specificity. The comparative advantage of BG and BG assays lied in excluding IFI in non-hematological PICU patients.

Practice Guidelines for the Diagnosis and Management of Aspergillosis: 2016 Update by the Infectious Diseases Society of America

It is important to realize that guidelines cannot always account for individual variation among patients. They are not intended to supplant physician judgment with respect to particular patients or special clinical situations. IDSA considers adherence to these guidelines to be voluntary, with the ultimate determination regarding their application to be made by the physician in the light of each patient's individual circumstances.

Pediatric Invasive Aspergillosis

Invasive aspergillosis (IA) is a disease of increasing importance in pediatrics due to growth of the immunocompromised populations at risk and improvements in long-term survival for many of these groups. While general principles of diagnosis and therapy apply similarly across the age spectrum, there are unique considerations for clinicians who care for children and adolescents with IA. This review will highlight important differences in the epidemiology, clinical manifestations, diagnosis, and therapy of pediatric IA.

Imaging fungal infections in children

Fungal infections in children rarely occur, but continue to have a high morbidity and mortality despite the development of newer antifungal agents. It is essential for these infections to be diagnosed at the earliest possible stage so appropriate treatment can be initiated promptly. The addition of high-resolution computer tomography (HR CT) has helped in early diagnosis making; however, it lacks both sensitivity and specificity. Metabolic changes precede anatomical changes and hybrid imaging with positron emission tomography (PET) integrated with imaging modalities with high anatomical resolution such as CT or magnetic resonance imaging (MRI) is likely to detect these infections at an earlier stage with higher diagnostic accuracy rates. Several authors presented papers highlighting the advantages of PET/CT in imaging fungal infections. These papers, however, usually involve a limited number of patients and mostly adults. Fungal infections behave different in children than in adults, since there are differences in epidemiology, imaging findings, and response to treatment with antifungal drugs. This paper reviews the literature and explores the use of hybrid imaging for diagnosis and therapy decision making in children with fungal infections.

Galactomannan detection for invasive aspergillosis in immunocompromised patients

BACKGROUND

Invasive aspergillosis is the most common life-threatening opportunistic invasive mycosis in immunocompromised patients. A test for invasive aspergillosis should neither be too invasive nor too great a burden for the already weakened patient. The serum galactomannan enzyme-linked immunosorbent assay (ELISA) seems to have the potential to meet both requirements.

OBJECTIVES

To obtain summary estimates of the diagnostic accuracy of galactomannan detection in serum for the diagnosis of invasive aspergillosis.

SEARCH METHODS

We searched MEDLINE, EMBASE and Web of Science with both MeSH terms and text words for both aspergillosis and the sandwich ELISA. We checked the reference lists of included studies and review articles for additional studies. We conducted the searches in February 2014.

SELECTION CRITERIA

We included cross-sectional studies, case-control designs and consecutive series of patients assessing the diagnostic accuracy of galactomannan detection for the diagnosis of invasive aspergillosis in patients with neutropenia or patients whose neutrophils are functionally compromised. The reference standard was composed of the criteria given by the European Organization for Research and Treatment of Cancer (EORTC) and the Mycoses Study Group (MSG).

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed quality and extracted data. We carried out meta-analysis using the bivariate method. We investigated sources of heterogeneity by adding potential sources of heterogeneity to the model as covariates.

MAIN RESULTS

We included 54 studies in the review (50 in the meta-analyses), containing 5660 patients, of whom 586 had proven or probable invasive aspergillosis. When using an optical density index (ODI) of 0.5 as a cut-off value, the sensitivity of the test was 82% (73% to 90%) and the specificity was 81% (72% to 90%). At a cut-off value of 1.0 ODI, the sensitivity was 72% (65% to 80%) and the specificity was 88% (84% to 92%). At a cut-off value of 1.5 ODI, the sensitivity was 61% (47% to 75%) and the specificity was 93% (89% to 97%). None of the potential sources of heterogeneity had a statistically significant effect on either sensitivity or specificity.

AUTHORS' CONCLUSIONS

If we used the test at a cut-off value of 0.5 ODI in a population of 100 patients with a disease prevalence of 9% (overall median prevalence), two patients who have invasive aspergillosis would be missed (sensitivity 82%, 18% false negatives), and 17 patients would be treated unnecessarily or referred unnecessarily for further testing (specificity 81%, 19% false negatives). If we used the test at a cut-off value of 1.5 in the same population, that would mean that four invasive aspergillosis patients would be missed (sensitivity 61%, 39% false negatives), and six patients would be treated or referred for further testing unnecessarily (specificity 93%, 7% false negatives). These numbers should, however, be interpreted with caution because the results were very heterogeneous.

Management of Invasive Fungal Infections in Pediatric Acute Leukemia and the Appropriate Time for Restarting Chemotherapy

OBJECTIVE

Rapid and effective treatment of invasive fungal infection (IFI) in patients with leukemia is important for survival. In this study, we aimed to describe variations regarding clinical features, treatment modalities, time of restarting chemotherapy, and outcome in children with IFI and acute leukemia (AL).

MATERIALS AND METHODS

The charts of all pediatric AL patients in our clinic between the years of 2001 and 2013 were retrospectively reviewed. All patients received prophylactic fluconazole during the chemotherapy period.

RESULTS

IFI was identified in 25 (14%) of 174 AL patients. Most of them were in the consolidation phase of chemotherapy and the patients had severe neutropenia. The median time between leukemia diagnosis and definition of IFI was 122 days. Twenty-four patients had pulmonary IFI. The most frequent finding on computed tomography was typical parenchymal nodules. The episodes were defined as proven in 4 (16%) patients, probable in 7 (28%) patients, and possible in 14 (56%) patients. The median time for discontinuation of chemotherapy was 27 days. IFI was treated successfully in all patients with voriconazole, amphotericin B, caspofungin, or posaconazole alone or in combination. Chemotherapy was restarted in 50% of the patients safely within 4 weeks and none of those patients experienced reactivation of IFI. All of them were given secondary prophylaxis. The median time for antifungal treatment and for secondary prophylaxis was 26 and 90 days, respectively. None of the patients died due to IFI.

CONCLUSION

Our data show that rapid and effective antifungal therapy with rational treatment modalities may decrease the incidence of death and that restarting chemotherapy within several weeks may be safe in children with AL and IFI.

Serum galactomannan screening for diagnosis of invasive pulmonary aspergillosis in children after stem cell transplantation or with high-risk leukemia

Both transplanted and leukemia patients are at high risk (HR) for invasive pulmonary aspergillosis (IPA). Methods for rapid diagnosis are crucial. Our objective was to investigate the impact of serial serum galactomannan assay (GMA) screening on IPA diagnosis in children. Between January 2010 and December 2011, all children following stem cell transplantation (SCT) or with HR leukemia were prospectively included. Serum samples for GMA were taken once-twice weekly. Results >.5 were considered positive. Patients suspected of having IPA were stratified as possible, probable, and definite. Forty-six children (median age, 8 years) were included, 38 after SCT (32 allogeneic), 8 with HR leukemia. A total of 510 samples were taken; screening period was 1-6 months for 34 patients. GMA was negative in 28 patients, all but one without suspicion of IPA. Eighteen patients had positive GMA: while four (22%) were upgraded to probable IPA, fourteen (78%) were considered as false positives (FP), some associated with piperacillin-tazobactam treatment. GMA sensitivity and specificity were 0.8 and 0.66, respectively; positive- and negative-predictive values (PPV, NPV) were 0.22 and 0.96, respectively. GMA may have a role in evaluating HR children for IPA. Both NPV and FP rates are high. The cost benefit of early detection versus over-diagnosis should be further studied.

Fourth European Conference on Infections in Leukaemia (ECIL-4): guidelines for diagnosis, prevention, and treatment of invasive fungal diseases in paediatric patients with cancer or allogeneic haemopoietic stem-cell transplantation

Invasive opportunistic fungal diseases (IFDs) are important causes of morbidity and mortality in paediatric patients with cancer and those who have had an allogeneic haemopoietic stem-cell transplantation (HSCT). Apart from differences in underlying disorders and comorbidities relative to those of adults, IFDs in infants, children, and adolescents are unique with respect to their epidemiology, the usefulness of diagnostic methods, the pharmacology and dosing of antifungal agents, and the absence of interventional phase 3 clinical trials for guidance of evidence-based decisions. To better define the state of knowledge on IFDs in paediatric patients with cancer and allogeneic HSCT and to improve IFD diagnosis, prevention, and management, the Fourth European Conference on Infections in Leukaemia (ECIL-4) in 2011 convened a group that reviewed the scientific literature on IFDs and graded the available quality of evidence according to the Infectious Diseases Society of America grading system. The final considerations and recommendations of the group are summarised in this manuscript.

Computed tomography guided percutaneous lung biopsies and suspected fungal infections in pediatric cancer patients

BACKGROUND

The spectrum of potential fungal pathogens known to cause invasive pulmonary infections has grown as a result of intensified immunosuppressive therapy and the emergence of antifungal resistance.

PROCEDURE

In a retrospective single center study, we investigated computed tomography guided percutaneous lung biopsies in 16 childhood patients with suspected fungal infections. Microbiological analysis consisted of microscopic examination, culture, and a broad-range fungal polymerase chain reaction for detection of either Aspergillus or Mucorales species.

RESULTS

In 14 patients (88%), invasive fungal infection with Aspergillus species including A. terreus, Mucormycetes, and Saccharomyces cerevisiae being the main pathogens was confirmed, including patients with a double infection (19%). In two cases, the most likely diagnosis of primary bronchiolitis obliterans organizing pneumonia was established based on the results of typical histopathologic features, negative culture results, and symptoms resolved after treatment with high-dose cortisone. Diagnosis of invasive fungal pneumonia led to an immediate interruption of antineoplastic treatment in 100%, reduction of antibiotic drugs in 76%, and change of empirical to targeted antifungal therapy in 63%. The safety of lung biopsy was guaranteed by lack of any complications, such as bleeding or pneumothorax.

CONCLUSIONS

The increased detection of rare fungal infections by computed tomography guided biopsy supports the need for a rapid and precise diagnosis, as most of the fungal pathogens are at least partially resistant to available antifungal therapy and proper treatment is essential for best practice in patient management.

Nonmolecular methods for the diagnosis of respiratory fungal infections

Diagnosis of invasive fungal pneumonias by conventional culture methods is difficult to assess and often delayed. Nonmolecular fungal markers have emerged as an important adjunctive tool to support their diagnosis in combination with other clinical, radiologic, and microbiological criteria of invasive fungal diseases. Concerns about the sensitivity and specificity of some tests in different patient populations should lead to warnings about their widespread use. None can identify the emerging and particularly deadly fungal pathogens responsible for mucormycosis. The role of nonmolecular fungal markers should be better defined in combination with other microbiological and radiologic tools in preemptive antifungal strategies.

Role of management strategies in reducing mortality from invasive fungal disease in children with cancer or receiving hemopoietic stem cell transplant: a single center 30-year experience

BACKGROUND

In the last decades, several diagnostic and therapeutic strategies have been implemented for management of invasive fungal diseases (IFD) in patients with cancer or receiving allogeneic hemopoietic stem cell transplant. Few data are available on their impact on mortality in children.

METHODS

All IFD episodes diagnosed at tertiary care center during a 30-year period between 1983 and 2012 were analyzed for 90-day mortality and risk factors. Diagnoses were coded according to international (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) criteria. Four treatment eras (1983-1990, 1991-1999, 2000-2005 and 2006-2012) were defined according to availability of diagnostic technologies, new antifungal drugs and use of a diagnostic-driven approach without empiric antifungal therapy.

RESULTS

A total of 198 IFD were diagnosed in 191 patients; 71.2% were proven/probable infections; 39.9% were caused by yeasts and 31.3% by molds. Within 90 days from IFD diagnosis, 58 (30.4%) patients died for a 28.3% cumulative probability of death. A multivariable analysis showed that the highest risk of death was associated with alternative donor-hemopoietic stem cell transplant [hazard ratio (HR): 3.96] and mold etiology (HR: 1.34). The risk of death significantly decreased across the treatment eras, with almost a 3-fold reduced risk for patients diagnosed during the 2006-2012 period (HR: 0.24). Also if the variable year of diagnosis was considered as continuous, the hazard of death significantly decreased by 5% per year (HR: 0.95).

CONCLUSIONS

New management strategies resulted in a better prognosis of IFD in children with cancer or hemopoietic stem cell transplant. A diagnostic-driven approach was not associated with an increase in mortality.

Guidelines for Management of Children With Fever and Neutropenia

Children presenting with fever and neutropenia (FN) pose unique diagnostic and management challenges. The absence of pediatric-specific guidelines has led physicians to rely on local expertise, interpretation of available data without benefit of national consensus, and extrapolation of adult guidelines for direction. However, the causes, treatment, and outcomes of children with FN differ in important ways from those of adults. Although individual studies have focused on different aspects of the management of FN in children, a universal approach has not been adopted. The literature review below provides a synopsis of a recently published international guideline on management of children with FN. The guideline reviewed represents the first evidence-based, consensus-driven approach to address management of FN in children.

Diagnosis of invasive pulmonary aspergillosis in children with bronchoalveolar lavage galactomannan

BACKGROUND

Invasive pulmonary aspergillosis (IPA) is a life-threatening complication in immunocompromised patients. Early diagnosis and therapy improves outcome. Assessment of galactomannan (GM) in bronchoalveolar lavage (BAL) fluid is a proposed tool to diagnose IPA. Little is known about the diagnostic value of BAL GM in children.

MATERIALS AND METHODS

Retrospectively, 72 bronchoscopies were analyzed for GM in patients fulfilling the host factor criteria as defined by the EORTC/MSG. A cut-off index value GM of ≥0.5 was used. Clinical data, results of chest CT-scans and BAL cultures were collected.

RESULTS

Sensitivity, specificity, PPV, and NPV of BAL GM for a diagnosis of proven and probable IPA (n = 41) were 82.4%, 87.5%, 82.4%, and 87.5% respectively. A significant relation was found for BAL GM and abnormal chest CT (P = 0.01). No significant relationship was observed between BAL Aspergillus sp. culture and chest CT (n = 47). BAL GM and serum GM correlated significantly. In 9 out of 12 patients classified as possible IPA, antifungal therapy was continued or started, despite a negative BAL GM.

CONCLUSIONS

BAL GM test had good diagnostic value in children suspected of IPA. However, the decision to continue or start antifungal therapy was mainly determined by the clinical suspicion of IPA based on chest CT-outcome, serum GM index values and failure of antibiotic therapy.

Aspergillus galactomannan antigen assay and invasive aspergillosis in pediatric cancer patients and hematopoietic stem cell transplant recipients

BACKGROUND

Invasive aspergillosis (IA) is a major cause of morbidity and mortality in immunocompromised children. We investigated the usefulness of an Aspergillus galactomannan (GM) antigen assay as a diagnostic tool for IA in pediatric cancer patients and hematopoietic cell transplantation (HCT) recipients.

PROCEDURE

The GM antigen assay results were analyzed in 749 blood samples from 99 patients. A GM index (GMI) greater than or equal to 0.5 on at least two separate occasions was considered positive. A review of the clinical data was performed for subjects with proven or probable IA.

RESULTS

Twenty-one of 23 patients with proven or probable IA had positive GM antigen test results (91.3% sensitivity, 95% CI 71.9-98.9; 81.7% specificity, 95% CI 69.6-90.5; P < 0.0001). The false-positive rate was 18.3%. Being younger than 3 years of age, having a solid tumor, and receiving HCT within 4 weeks of the test were statistically significant factors for causing false-positive results (P < 0.05). Among the 23 patients with IA (six proven, 17 probable), 16 (69.6%) had hematological malignancies, five (22.7%) had solid tumors, and two (8.7%) had primary immunodeficiency. Nineteen patients (82.6%) received HCT. The most common clinical site of IA was the lungs (91.3%), and consolidation was the most frequent finding in chest CT scans (36.8%). The mortality at 12 weeks was 43.5%.

CONCLUSIONS

Having a positive GM assay at least twice is useful in diagnosing IA in pediatric patients with cancer and HCT recipients.

The Role of Biomarkers for Diagnosis of and Therapeutic Decisions Related to Invasive Aspergillosis in Children

Invasive aspergillosis (IA) is a feared opportunistic infection for many immuncompromised children resulting in significant morbidity and mortality. Timely diagnosis based on traditional testing modalities and clinical evaluation has proven to be challenging. Assays designed to measure IA biomarkers such as galactomannan (GM) and beta-D-glucan (BG) represent a potential significant improvement in the ability to diagnose pediatric IA. However, as with any new diagnostic tool, clinicians need to be aware of the operating characteristics of these assays in order to apply them in the appropriate settings. Published adult and pediatric data regarding GM and BG testing are reviewed and guidance regarding the appropriate utility of these assays in children is offered.

Guideline for the management of fever and neutropenia in children with cancer and/or undergoing hematopoietic stem-cell transplantation

PURPOSE

To develop an evidence-based guideline for the empiric management of pediatric fever and neutropenia (FN).

METHODS

The International Pediatric Fever and Neutropenia Guideline Panel is a multidisciplinary and multinational group composed of experts in pediatric oncology and infectious disease as well as a patient advocate. The Panel was convened for the purpose of creating this guideline. We followed previously validated procedures for creating evidence-based guidelines. Working groups focused on initial presentation, ongoing management, and empiric antifungal therapy. Each working group developed key clinical questions, conducted systematic reviews of the published literature, and compiled evidence summaries. The Grades of Recommendation Assessment, Development, and Evaluation approach was used to generate summaries, and evidence was classified as high, moderate, low, or very low based on methodologic considerations.

RESULTS

Recommendations were made related to initial presentation (risk stratification, initial evaluation, and treatment), ongoing management (modification and cessation of empiric antibiotics), and empiric antifungal treatment (risk stratification, evaluation, and treatment) of pediatric FN. For each recommendation, the strength of the recommendation and level of evidence are presented.

CONCLUSION

This guideline represents an evidence-based approach to FN specific to children with cancer. Although some recommendations are similar to adult-based guidelines, there are key distinctions in multiple areas. Implementation will require adaptation to the local context.

Antifungal prophylaxis in pediatric hematology/oncology: new choices & new data

A severe complication of the treatment of pediatric cancers is the development of an invasive fungal infection (IFI). The data to support antifungal prophylaxis in pediatric oncology patients derive primarily from adult patients, and thus the optimal agent to utilize is not clear. Fluconazole has been a standard option, but agents with antimold activity are now available, each with limitations. Pediatric dosing for voriconazole and posaconazole is uncertain and multiple drug interactions exist. The echinocandins are well-tolerated, but only available in intravenous form. Ultimately, studies demonstrating biologic risk factors for the development of IFI may lead to personalized prophylactic strategies.

Invasive Mold Infections in Pediatric Cancer Patients Reflect Heterogeneity in Etiology, Presentation, and Outcome: A 10-Year, Single-Institution, Retrospective Study

BACKGROUND

There is scarcity of data regarding invasive mold infections (IMIs) in children with cancer.

METHODS

We retrospectively identified patients (18 years old or younger) with malignant disease who developed proven or probable IMIs (European Organization for Research on the Treatment of Cancer/Mycoses Study Group criteria) during a 10-year period (1998-2008). We reviewed their risk factors and clinical characteristics and assessed their crude mortality rates and treatment outcomes 12 weeks after IMI diagnosis.

RESULTS

Forty-eight patients (30 males) were identified, 30 (63%) of whom had a proven IMI. The most prevalent mold were Aspergillus species (40%), followed by Mucorales (20%) and Fusarium species (11%). Acute leukemia was the most common underlying malignancy (39 patients, [81%]). Twenty-three (59%) of them had refractory leukemia. Neutropenia was present at the day of IMI diagnosis in 67% of the patients. Sixty-two percent of the patients received prior corticosteroids. The dominant site of infection was the lungs (79%), followed by skin (29%) and sinuses (10%). Seventy-one percent of patients had radiological findings suggestive of fungal pneumonia (either nodules or masses). The mainstay of antifungal therapy was a lipid formulation of amphotericin B. Antifungal therapy resulted in 54% response rate (33% complete) at 12 weeks. The crude 12-week mortality rate was 31%. Logistic regression analysis demonstrated that monocytopenia (P = .013), malnutrition (P = .012), and intensive care admission in the month prior to IMI diagnosis (P = .027) were risk factors for death within 12 weeks.

CONCLUSIONS

Although Aspergillus spp. was the most common mold in our pediatric cancer population, the epidemiology of the IMIs was diverse. Adults and children share similar risk factors for and epidemiology of IMIs.

Galactomannan Antigen Testing for Diagnosis of Invasive Aspergillosis in Pediatric Hematology Patients

OBJECTIVE

Invasive aspergillosis (IA) can cause significant morbidity and mortality in immunocompromised children. The galactomannan (GM) enzyme immunoassay (EIA) has been shown in adult studies to be a useful adjunct in diagnosing IA. Data on this assay in children are limited by small sample sizes and conflicting results; false-positive assays were a concern in historical studies. We sought to evaluate the GM EIA in a large cohort of children who received intensive chemotherapy and/or hematopoietic stem cell transplant. A focus was placed on evaluating the assay specificity, and the potential of measuring GM antigen in urine.

METHODS

A multicenter prospective observational study in children with anticipated prolonged neutropenia was performed. Serum specimens were collected twice weekly, and urine was collected once weekly during neutropenic periods. Operating characteristics were calculated using the GM EIA optical density index cutoffs of 0.5 and 1.0 for both serum and urine specimens.

RESULTS

At least one serum or urine specimen was tested from 198 patients. Ten patients had one or more repeatedly positive serum specimens, while 37 patients had one or more repeatedly positive urine specimens. The specificity of serum and urine testing was 95% and 80%, respectively. Although the urine test resulted in a higher false positivity rate, it successfully identified the only case of probable IA.

CONCLUSIONS

Data suggest that the serum GM EIA does not provide frequent false-positive results as previously reported. Screening for galactomannan, or a related antigen in urine, needs to be further evaluated as it may be amenable to development of surveillance strategies.

A novel extraction method combining plasma with a whole-blood fraction shows excellent sensitivity and reproducibility for patients at high risk for invasive aspergillosis

Diagnosis of invasive aspergillosis (IA) is still a major problem in routine clinical practice. Early diagnosis is essential for a good patient prognosis. PCR is a highly sensitive method for the detection of nucleic acids and could play an important role in improving the diagnosis of fungal infections. Therefore, a novel DNA extraction method, ultraclean production (UCP), was developed allowing purification of both cellular and cell-free circulating fungal DNA. In this prospective study we evaluated the commercially available UCP extraction system and compared it to an in-house system. Sixty-three patients at high risk for IA were screened twice weekly, and DNA extracted by both methods was cross-analyzed, in triplicate, by two different real-time PCR assays. The negative predictive values were high for all methods (94.3 to 100%), qualifying them as screening methods, but the sensitivity and diagnostic odds ratios were higher using the UCP extraction method. Sensitivity ranged from 33.3 to 66.7% using the in-house extracts to 100% using the UCP extraction method. Most of the unclassified patients showed no positive PCR results; however, single-positive PCR replicates were observed in some cases. These can bear clinical relevance but should be interpreted with additional clinical and laboratory data. The PCR assays from the UCP extracts showed greater reproducibility than the in-house method for probable IA patients. The standardized UCP extraction method yielded superior results, with regard to sensitivity and reproducibility, than the in-house method. This was independent of the PCR assay used to detect fungal DNA in the sample extracts.