Invasive fungal disease in pediatric acute leukemia patients with fever and neutropenia during induction chemotherapy: a multivariate analysis of risk factors

A comprehensive assessment of the prolonged febrile neutropenia evaluation in pediatric oncology patients

BACKGROUND

Pediatric oncology patients with prolonged (≥96 hours) febrile neutropenia (absolute neutrophil count < 500/μL) often undergo an evaluation for invasive fungal disease (IFD) and other infections. Current literature suggests that beta-D-glucan (BDG), galactomannan, bronchoalveolar lavage (BAL), and computed tomography (CT) scans (sinus, chest, and abdomen/pelvis) may help determine a diagnosis in this population.

METHODS

In a retrospective cohort study of all cancer/stem cell transplant patients (diagnosed 2005-2019) from one pediatric hospital, all episodes with prolonged febrile neutropenia or IFD evaluations (defined as sending a fungal biomarker or performing a CT scan to assess for infection) were identified.

RESULTS

In total, 503 episodes met inclusion criteria and 64% underwent IFD evaluations. In total, 36.4% of episodes documented an infection after initiation of prolonged febrile evaluation, most commonly Clostridioides difficile colitis (6.4%) followed by a true bacterial bloodstream infection (BSI) (5.2%), proven/probable IFD (4.8%), and positive respiratory pathogen panel (3.6%). There was no difference in sinus CTs showing sinusitis (74% vs 63%, p = 0.46), whereas 32% of abdomen/pelvis CTs led to a non-IFD diagnosis, and 25% of chest CTs showed possible pneumonia. On chest CT, the positive predictive value (PPV) for IFD was 19% for nodules and 14% for tree and bud lesions. BDG had a PPV of 25% for IFD and GM 50%. BAL diagnosed IFD once and pneumocystis jirovecii pneumonia twice.

CONCLUSIONS

Chest CTs and abdomen/pelvis CTs provide clinically relevant information during the prolonged febrile neutropenia evaluation, whereas BDG, galactomannan, BAL, and sinus CTs have less certain utility.

Predictors of Candidemia during Febrile Episode in Lymphoreticular Malignancy Affecting Paediatric Population

Limited studies on candidemia in malignancy in the paediatric population from developing countries show a high incidence, high morbidity and a unique epidemiology as compared to developed nations. Our prospective observational study aimed to explore the prevalence of invasive candidiasis, especially candidemia, in febrile paediatric patients with lymphoreticular malignancy. A sample size of 49 children, with 100 recorded febrile episodes was studied. The relevance of candida colonization and mannan antigen detection as indicators of impending candidemia was evaluated. Genotypic identification of the yeast isolates was followed by sequence analysis using the NCBI-BLAST program, and the generation of the phylogenetic tree using MEGA 6.0 software. We observed a 5% prevalence of candidemia among febrile paediatric patients with lymphoreticular malignancy, predominantly caused by non-albicans candida. Colonization at multiple anatomical sites decreased from day 1 to day 8 of febrile episodes. Significant candida colonization (colonization index ≥0.5) was seen in a larger proportion of candidemia patients on day 1 and day 4 (p < 0.001) displaying a definite association between the two. The receiver operator characteristic (ROC) curve analysis for mannan antigen level revealed a cut-off of ≥104.667 pg/mL, suitable for predicting candidemia with a sensitivity of 100%, specificity of 92% and area under ROC value of 0.958 (95% CI: 0.915-1; p < 0.001). A phylogenetic tree with three population groups, clade 1, 2 and 3, consisting of Candida auris (1), Candida tropicalis (2) and Candida parapsilosis (2), respectively, was generated. The diagnosis of candidemia based on mannan antigen detection gives early results and has high negative predictive values. It can be combined with other biomarkers to increase sensitivity, specificity and positive predictive value.

Aspergillus appendicitis complicating chemotherapy of leukemia: A case report and review of the literature

Introduction

The diagnosis of primary Aspergillus appendicitis can be missed or delayed because of its rarity. We report our experience of a case of Aspergillus appendicitis complicating chemotherapy of leukemia.

Presentation of case

A 48-year-old man who was diagnosed with acute myeloid leukemia developed high fever and epigastric pain two weeks after administration of his fourth consolidation chemotherapy. Right lower quadrant tenderness and rebound tenderness were noticed on physical examination, and the abdomen and pelvis computed tomography suggested acute perforated appendicitis with localized peritonitis. Emergency laparoscopy showed an inflamed appendix, which was resected. Pathology reports revealed invasive aspergillosis in the appendix. The patient recovered after high-dose antifungal therapy, although he required prolonged hospitalization.

Discussion

Acute appendicitis is very rarely caused by fungi infection with an overall incidence of up to 1.15 %. Differential diagnosis of fungal appendicitis without pathology report is challenging due to low incidence.

Conclusion

Isolated Aspergillus appendicitis is a rare disease that can progress without appropriate antifungal therapy even after surgical resection of the appendix. Surgeons should pay attention to pathology reports after appendectomy to avoid missing unusual cases, especially in immunocompromised patients.

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Fungal infections principally occur in the immunocompromised.

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Misdiagnosis and incorrect treatment are frequent in this rare disease entity.

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Early diagnosis and prompt surgery with antifungal treatment is best

When Is It Appropriate to Take Off the Mask? Signaling Pathways That Regulate ß(1,3)-Glucan Exposure in Candida albicans

Candida spp. are an important source of systemic and mucosal infections in immune compromised populations. However, drug resistance or toxicity has put limits on the efficacy of current antifungals. The C. albicans cell wall is considered a good therapeutic target due to its roles in viability and fungal pathogenicity. One potential method for improving antifungal strategies could be to enhance the detection of fungal cell wall antigens by host immune cells. ß(1,3)-glucan, which is an important component of fungal cell walls, is a highly immunogenic epitope. Consequently, multiple host pattern recognition receptors, such as dectin-1, complement receptor 3 (CR3), and the ephrin type A receptor A (EphA2) are capable of recognizing exposed (unmasked) ß(1,3)-glucan moieties on the cell surface to initiate an anti-fungal immune response. However, ß(1,3)-glucan is normally covered (masked) by a layer of glycosylated proteins on the outer surface of the cell wall, hiding it from immune detection. In order to better understand possible mechanisms of unmasking ß(1,3)-glucan, we must develop a deeper comprehension of the pathways driving this phenotype. In this review, we describe the medical importance of ß(1,3)-glucan exposure in anti-fungal immunity, and highlight environmental stimuli and stressors encountered within the host that are capable of inducing changes in the levels of surface exposed ß(1,3)-glucan. Furthermore, particular focus is placed on how signal transduction cascades regulate changes in ß(1,3)-glucan exposure, as understanding the role that these pathways have in mediating this phenotype will be critical for future therapeutic development.

Clinical Characteristics and Predictive Factors of Invasive Fungal Disease in Pediatric Oncology Patients with Febrile Neutropenia in a Country with Limited Resources

Background

The most common complication among pediatric oncology patients is febrile neutropenia (FN). Invasive fungal disease (IFD) is suspected when fever persists >4–7 days after empirical antibiotics. Its clinical characteristics and predictive factors associated with IFD among pediatric oncology patients with FN were thus explored.

Methods

Pediatric oncology patients with FN between January 1, 2012 and December 31, 2016 were enrolled in this study. Clinical characteristics, including laboratory investigations, treatment modalities, and final outcomes of IFD were retrospectively reviewed and analyzed.

Results

In all, 73 patients with 180 episodes of confirmed diagnosis of FN were studied. Median age at diagnosis was 6.2 years, with equal sex distribution. The most common diagnosis was acute lymphoblastic leukemia (n=91, 51%), followed by acute myeloid leukemia (n=47, 26%), Burkitt’s lymphoma (n=7, 4%) and neuroblastoma (n=7, 4%). Median absolute neutrophil count at FN diagnosis was 0 (0–806) cells/mm³. IFD was diagnosed for 25 (14%) episodes. Mortality rates for FN and IFD were 4% and 20%, respectively. Respiratory compromise, oxygen requirement, hypotension, prolonged hospitalization, duration of fever and neutropenia, bacteremia, bacteriuria, funguria, abnormal liver-function results, and prolonged broad-spectrum antibiotic administration were factors associated with IFD (P<0.05). Prolonged duration between initiation of fever and antifungal administration for nearly 10 days was an independent factor in prediction of IFD occurrence (P=0.014).

Conclusion

Respiratory compromise, oxygen requirement, hypotension, prolonged hospitalization, duration of fever and neutropenia, bacteremia, bacteriuria, funguria, abnormal liver-function results and prolonged broad-spectrum antibiotic administration were factors associated with IFD. Duration between initiation of fever and antifungal administration of nearly 10 days were considered a risk factors of IFD among patients with FN.

IRB Reference Number

IRBRTA 825/2560.

A non-randomized trial to assess the safety, tolerability, and pharmacokinetics of posaconazole oral suspension in immunocompromised children with neutropenia

Background

Posaconazole (POS) is a potent triazole antifungal agent approved in adults for treatment and prophylaxis of invasive fungal infections (IFIs). The objectives of this study were to evaluate the pharmacokinetics (PK), safety, and tolerability of POS oral suspension in pediatric subjects with neutropenia.

Methods

This was a prospective, multicenter, sequential dose-escalation study. Enrolled subjects were divided into 3 age groups: AG1, 7 to <18 years; AG2, 2 to <7 years; and AG3, 3 months to <2 years. AG1 and AG2 were divided into 3 dosage cohorts: DC1, 12 mg/kg/day divided twice daily (BID); DC2, 18 mg/kg/day BID; and DC3, 18 mg/kg/day divided thrice daily (TID). AG3 was also divided into DC1 and DC2; however, no subjects were enrolled in DC2. Subjects received 7–28 days of POS oral suspension. PK samples were collected at predefined time points. The POS PK target was predefined as ~90% of subjects with C_avg (AUC /dosing interval) between 500 and 2500 ng/mL, with an anticipated mean steady state C_avg exposure of ~1200 ng/mL.

Results

The percentage of subjects meeting the PK target was <90% across all age groups and dosage cohorts (range: 31% to 80%). The percentage of subjects that achieved the C_avg target of 500 to 2500 ng/mL on Day 7 ranged from 31% to 80%, with the lowest proportion in subjects 2 to <7 years receiving 12 mg/kg/day BID (AG2/DC1) and the highest proportion in subjects 7 to <18 years receiving 18 mg/kg/day TID (AG1/DC3). At all three dose levels (12 mg/kg/day BID, 18 mg/kg/day BID and 18 mg/kg/day TID), subjects in AG1 (7 to <18 years old) had higher mean PK exposures at steady state than those in AG2. High variability in exposures was observed in all groups. POS oral suspension was generally well tolerated and most of the reported adverse events were related to the subjects’ underlying diseases.

Conclusion

The POS PK target of 90% of subjects with C_avg between 500 and 2500 ng/mL was not achieved in any of the age groups across the different dosage cohorts. New formulations of the molecule with a greater potential to achieve the established PK target are currently under investigation.

Trial registration

ClinicalTrials.gov identifier: NCT01716234

Prevalence and Predictors of Invasive Fungal Infections in Children with Persistent Febrile Neutropenia Treated for Acute Leukemia - A Prospective Study

OBJECTIVE

To ascertain the prevalence of invasive fungal infections (IFI), predictors of IFI, identify etiological species and outcome (mortality/discharge) in persistent febrile neutropenia in children with acute leukemia.

METHODS

It was a prospective, observational study conducted from January 2013 through June 2014 in a tertiary care centre in New Delhi. Children between 1 and 12 y of age, on chemotherapy for acute leukemia with persistent febrile neutropenia (> 96 h) were enrolled. These children were not on any antifungal prophylaxis. Diagnosis of IFI was based on European Organization for Research and Treatment of Cancer and Mycoses Study Group (EORTC/MSG) criteria. Prevalence and outcome was reported in mean ± 95% CI form and etiological species were presented in the form of the frequency distribution.

RESULTS

Three hundred nineteen episodes involving 187 children of febrile neutropenia were screened and 74 were enrolled. Prevalence of IFI was 22.97% (13.99-34.21). Positive cases were further classified into proven 3(17.6%), probable 11(64.8%) and possible 3(17.6%) according to EORTC/MSG criteria. On multivariate analysis, abnormal CXR and clinical sinusitis were important predictors of IFI. Most common fungi isolated was Aspergillus sp. followed by Candida sp. Mortality rate was 9.45% (3.89-18.52).

CONCLUSIONS

Thus, prevalence of IFI is very high in children with persistent febrile neutropenia who are not on antifungal prophylaxis. Abnormal chest x- ray and clinical sinusitis are important predictors of IFI.

Risk Factors for Invasive Fungal Disease in Pediatric Cancer and Hematopoietic Stem Cell Transplantation: A Systematic Review

BACKGROUND

Although a number of risk factors have been associated with invasive fungal disease (IFD), a systematic review of the literature to document pediatric-specific factors has not been performed.

METHODS

We used the Ovid SP platform to search Medline, Medline In-Process, and Embase for studies that identified risk factors for IFD in children with cancer or those who undergo hematopoietic stem cell transplantation (HSCT). We included studies if they consisted of children or adolescents (<25 years) who were receiving treatment for cancer or undergoing HSCT and if the study evaluated risk factors among patients with and those without IFD.

RESULTS

Among the 3566 studies screened, 22 studies were included. A number of pediatric factors commonly associated with an increased risk for IFD were confirmed, including prolonged neutropenia, high-dose steroid exposure, intensive-timing chemotherapy for acute myeloid leukemia, and acute and chronic graft-versus-host disease. Increasing age, a factor not commonly associated with IFD risk, was identified as a risk factor in multiple published cohorts.

CONCLUSIONS

With this systematic review, we have confirmed IFD risk factors that are considered routinely in daily clinical practice. Increasing age should also be considered when assessing patient risk for IFD. Future efforts should focus on defining more precise thresholds for a particular risk factor (ie, age, neutropenia duration) and on development of prediction rules inclusive of individual factors to further refine the risk prediction.

Antifungal consumption, indications and selection of antifungal drugs in paediatric tertiary hospitals in Turkey: Results from the first national point prevalence survey

OBJECTIVES

The aim of this point prevalence survey was to evaluate the consumption, indications and strategies of antifungal therapy in the paediatric population in Turkey.

METHODS

A point prevalence study was performed at 25 hospitals. In addition to general data on paediatric units of the institutes, the generic name and indication of antifungal drugs, the presence of fungal isolation and susceptibility patterns, and the presence of galactomannan test and high-resolution computed tomography (HRCT) results were reviewed.

RESULTS

A total of 3338 hospitalised patients were evaluated. The number of antifungal drugs prescribed was 314 in 301 patients (9.0%). Antifungal drugs were mostly prescribed in paediatric haematology and oncology (PHO) units (35.2%), followed by neonatal ICUs (NICUs) (19.6%), paediatric services (18.3%), paediatric ICUs (PICUs) (14.6%) and haematopoietic stem cell transplantation (HSCT) units (7.3%). Antifungals were used for prophylaxis in 147 patients (48.8%) and for treatment in 154 patients (50.0%). The antifungal treatment strategy in 154 patients was empirical in 77 (50.0%), diagnostic-driven in 29 (18.8%) and targeted in 48 (31.2%). At the point of decision-making for diagnostic-driven antifungal therapy in 29 patients, HRCT had not been performed in 1 patient (3.4%) and galactomannan test results were not available in 12 patients (41.4%). Thirteen patients (8.4%) were receiving eight different antifungal combination therapies.

CONCLUSION

The majority of antifungal drugs for treatment and prophylaxis were prescribed in PHO and HSCT units (42.5%), followed by ICUs. Thus, antifungal stewardship programmes should mainly focus on these patients within the availability of diagnostic tests of each hospital.

Voriconazole Antifungal Prophylaxis in Children With Malignancies: A Nationwide Study

BACKGROUND

Antifungal prophylaxis (AFP) is recommended in at-risk hematology-oncology patients. We evaluated the safety of AFP with voriconazole (VRC) in pediatric hematology/oncology patients.

MATERIALS AND METHODS

A retrospective study of VRC AFP in children with malignancies hospitalized in all 7 Greek pediatric hematology/oncology centers during 2008 to 2012 was conducted. Patients' demographics, outcome, and adverse event (AE) data were recorded.

RESULTS

Four hundred twenty-nine VRC AFP courses in 249 patients (median age 6 y, 55% boys) were studied. The most common underlying diseases were acute lymphoblastic leukemia (51%), non Hodgkin lymphoma (8.6%), and acute myeloid leukemia (7.7%). The median number of VRC courses per patient was 1.7, whereas the median VRC dose was 7 mg/kg (range, 5 to 7 mg/kg) every 12 hours. During the last 2 weeks before AFP, 51% of the patients had received corticosteroids, 43% suffered from severe neutropenia, and 17.3% from mucositis. The median duration of VRC AFP was 17 days (range, 1 to 31 d). A single breakthrough fungemia due to Candida glabrata was recorded. Only 1 patient died due to the underlying disease. The most common AEs reported in 70/429 (16.3%) courses with ≥1 AE were elevated liver enzymes (50%), hypokalemia (24.3%), and ophthalmological disorders (14.3%). The median time of AE onset was 5 days (range, 1 to 21 d). Among 70 AEs reported, 38.5%, 48.4%, and 12.8% were of grade I, II, and III, respectively.

CONCLUSIONS

VRC prophylaxis in pediatric hematology/oncology patients appears to be well tolerated.

Guideline for the Management of Fever and Neutropenia in Children With Cancer and Hematopoietic Stem-Cell Transplantation Recipients: 2017 Update

Purpose To update a clinical practice guideline (CPG) for the empirical management of fever and neutropenia (FN) in children with cancer and hematopoietic stem-cell transplantation recipients. Methods The International Pediatric Fever and Neutropenia Guideline Panel is a multidisciplinary and multinational group of experts in pediatric oncology and infectious diseases that includes a patient advocate. For questions of risk stratification and evaluation, we updated systematic reviews of observational studies. For questions of therapy, we conducted a systematic review of randomized trials of any intervention applied for the empirical management of pediatric FN. The Grading of Recommendation Assessment, Development and Evaluation approach was used to make strong or weak recommendations and to classify levels of evidence as high, moderate, low, or very low. Results Recommendations related to initial presentation, ongoing management, and empirical antifungal therapy of pediatric FN were reviewed; the most substantial changes were related to empirical antifungal therapy. Key differences from our 2012 FN CPG included the listing of a fourth-generation cephalosporin for empirical therapy in high-risk FN, refinement of risk stratification to define patients with high-risk invasive fungal disease (IFD), changes in recommended biomarkers and radiologic investigations for the evaluation of IFD in prolonged FN, and a weak recommendation to withhold empirical antifungal therapy in IFD low-risk patients with prolonged FN. Conclusion Changes to the updated FN CPG recommendations will likely influence the care of pediatric patients with cancer and those undergoing hematopoietic stem-cell transplantation. Future work should focus on closing research gaps and on identifying ways to facilitate implementation and adaptation.

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.

Interferon-gamma Immunotherapy in a Patient With Refractory Disseminated Candidiasis

Despite advances in supportive care and novel antifungal agents, mortality caused by invasive Candida infection is high. A 3-year-old boy with disseminated Candida dubliniensis infection during induction chemotherapy for acute lymphoblastic leukemia deteriorated despite resolution of neutropenia and appropriate antifungal treatment. Monocyte human leukocyte antigen-DR expression was extremely low, suggesting immunoparalysis. Adjuvant immunotherapy with interferon-gamma restored the immune response, which was accompanied by clinical and radiographic recovery.

Adoptive T-cell therapy for fungal infections in haematology patients

The prolonged immune deficiency resulting from haematopoietic stem cell transplant and chemotherapy predisposes to a high risk of invasive fungal infections. Despite the recent advances in molecular diagnostic testing, early initiation of pre-emptive antifungal therapy and the use of combination pharmacotherapy, mortality from invasive mould infections remain high among recipients of allogeneic stem cell transplant. The increasing incidences of previously rare and drug-resistant strains of fungi present a further clinical challenge. Therefore, there is a need for novel strategies to combat fungal infections in the immunocompromised. Adoptive therapy using in vitro-expanded fungus-specific CD4 cells of the Th-1 type has shown clinical efficacy in murine studies and in a small human clinical study. Several techniques for the isolation and expansion of fungus-specific T cells have been successfully applied. Here we discuss the incidence and changing patterns of invasive fungal diseases, clinical evidence supporting the role of T cells in fungal immunity, methods to expand fungus-specific T cells in the laboratory and considerations surrounding the use of T cells for fungal immunotherapy.

Prevention of Fungal Infections in Hematology Patients

Endogenous infections such as candidiasis can be minimized by oral fluconazole prophylaxis, although oral or intravenous amphotericin, or itraconazole, are suitable for certain patients. Exogenous fungal infections most commonly are transmitted by the airborne route, but the benefits of high-efficiency particulate air-filtered room air probably are diminishing as broad-spectrum prophylaxis againstAspergillusspecies and other fungi improves. However, high-risk environmental sources such as construction work always must be avoided near neutropenic patients. Reactivation of quiescent pulmonaryAspergillusinfection can be prevented by surgical resection during remission, or by systemic amphotericin prophylaxis during subsequent neutropenic episodes.

Fungal infections in cancer patients

Invasive fungal infections (IFI) have become a leading cause of morbidity and mortality in cancer patients. Infections with these organisms are often difficult to diagnose and treat. Appropriate and timely diagnosis requires a high index of suspicion and invasive procedures, including biopsy, to confirm the diagnosis. Treatment may be difficult, secondary to variable susceptibility and difficulty with exact and specific characterization of the fungal pathogen. The pathogens that are seen range from yeasts to invasive molds. Fortunately newer, noninvasive diagnostic techniques are available to aid in the diagnosis and treatments have become better tolerated and more efficacious.

Antifungal prophylaxis associated with decreased induction mortality rates and resources utilized in children with new-onset acute myeloid leukemia

BACKGROUND

Invasive fungal infections cause significant morbidity and mortality for children with acute myeloid leukemia (AML). Data on the comparative effectiveness of antifungal prophylaxis in this population are limited.

METHODS

A pediatric AML cohort was assembled from the Pediatric Health Information System database using ICD-9 codes and pharmacy data. Antifungal prophylaxis status was determined by pharmaceutical data review within 21 days of starting induction chemotherapy. Patients were followed until end of induction, death, or loss to follow-up. Cox regression analyses compared induction mortality and resources utilized between patients receiving and not receiving antifungal prophylaxis. A propensity score accounted for variation in demographic factors, location of care, and severity of illness at presentation.

RESULTS

Eight hundred seventy-one AML patients were identified; the induction case fatality rate was 3.7%. In the adjusted Cox regression model, patients receiving antifungal prophylaxis (57%) had a decreased hazard for induction mortality (hazard ratio [HR], 0.42; 95% confidence interval [CI], .19-.90). Children receiving prophylaxis were less frequently exposed to broad-spectrum gram-positive (incidence rate ratio [IRR], 0.87; 95% CI, .79-.97) and antipseudomonal β-lactam agents (HR, 0.91; 95% CI, .85-.96), had fewer blood cultures (IRR, 0.78; 95% CI, .71-.86), and had fewer chest CT scans (IRR, 0.73; 95% CI, .60-.88).

CONCLUSIONS

Antifungal prophylaxis in pediatric AML patients was associated with reduced induction mortality rates and supportive care resources. Further investigation is necessary to determine whether antifungal prophylaxis should include antimold activity.

Oral voriconazole versus intravenous low dose amphotericin B for primary antifungal prophylaxis in pediatric acute leukemia induction: a prospective, randomized, clinical study

PURPOSE

Invasive fungal infections (IFI) are a major cause of infection-related mortality during induction chemotherapy of acute leukemia (AL) patients. Data on antifungal prophylaxis (AFP) in children are limited by retrospective design, small sample size, and variability of chemotherapy phases having different risk of IFI. There are no data comparing voriconazole versus amphotericin B (AmB) as AFP in either adult/pediatric AL. The objectives of this study were to compare efficacy and toxicity of AmB and voriconazole as AFP in pediatric AL patients.

PATIENTS AND METHODS

As a pilot study, total 100 children (≤15 y) with denovo acute myeloid leukemia and acute lymphoblastic leukemia were randomized to either oral voriconazole or low dose intravenous AmB as AFP during induction chemotherapy.

RESULTS

Failure of prophylaxis occurred in 14/50 patients in voriconazole arm (1 proven mucormycosis, 1 possible IFI, 11 empirical antifungal therapy, and 1 withdrawal owing to hepatotoxicity) and 17/50 patients in AmB arm (3 possible IFI, 13 empirical antifungal therapy, and 1 withdrawal owing to difficult venous access) (P=0.66). Of the 29 patients who had failure of prophylaxis unrelated to drug toxicity, computed tomography of the chest showed infiltrates in 10 patients with 3/12 in voriconazole arm and 7/16 in AmB arm (P=0.43). Drug-related serious adverse events were 6% versus 30% in voriconazole and AmB arms, respectively (P<0.01). Further, total number of toxicities per patient in AmB arm were significantly higher as compared with voriconazole arm (P<0.0001).

CONCLUSION

This is the first randomized study comparing voriconazole with AmB in pediatric AL patients as AFP during induction chemotherapy; our results showed that oral voriconazole seems to be comparable with AmB with less toxicity and more convenience. (ClinicalTrials.gov identifier: NCT00624143).

Two-way analysis for detecting factors affecting ventilator-associated pneumonia

The "clinically required ventilation period" for assessing ventilator-associated pneumonia (VAP) has not been studied because this period could not be clinically predicted. We addressed this problem using both rate analysis and failure-time analysis. A total of 325 patients who had received mechanical ventilatory support in the intensive care unit of a university hospital were reviewed. The total ventilation period and the ventilation period before VAP were compared using logistic regression and the Cox proportional hazard model for univariate and multivariate analyses. The Frechet distribution model was also used. Fifty patients were excluded for having pneumonia before intubation or for being admitted to a department in which no VAP occurred; 12 patients had VAP. Discrepancies in both methods caused by time-dependent bias were observed in patients emergently admitted (odds ratio, 1.435; hazard ratio, 0.3928). This reduced hazard ratio remained with the multivariate Frechet distribution model. Longer operation time significantly increased the VAP rate in the logistic model only. Low body mass index increased the rate of VAP in both models, especially in female patients (hazard ratio, 0.1707; 95% confidence interval, 0.02105-0.6728). The results of rate analysis and failure-time analysis were similar for most factors but differed somewhat for several factors, such as emergency admission. Unknown factors might be obscured by this type of difference, and this two-way method might be able to reveal artificial effects.

Invasive fungal infections in pediatric leukemia patients receiving fluconazole prophylaxis

BACKGROUND

Children with acute leukemia have increased risk for invasive fungal infections (IFI) but the role of long term antifungal prophylaxis (AFP) in morbidity and mortality of IFI is not well-known.

PROCEDURE

Medical records of 154 children with acute leukemia who received AFP with fluconazole during intensive chemotherapy were retrospectively reviewed to determine risk factors, clinical characteristics and outcome of IFI.

RESULTS

The overall incidence of IFI was 13.6%. Frequencies of proven, probable and possible infections were 7.2%, 2.6%, and 3.8%, respectively. The causative agent was Candida in 12 (57.2%) and Aspergillus in 9 (42.8%) children. There were 10 children with candidemia (47.6%), 7 with pulmonary aspergillosis (33.4%), 2 with hepatosplenic candidiasis (10.0%), one with sinopulmonary aspergillosis (4.5%) and one with sinus aspergillosis (4.5%). IFI was twice as common in acute myeloid leukemia (AML) (20.7%) than in acute lymphoblastic leukemia (ALL) (10.2%). Duration of profound neutropenia (P = 0.01) and steroid medications (P = 0.001) were significantly associated with IFI in univariate but not in multivariate analysis. Liposomal amphotericin B (L-AMB) was successful in 15 of 21 children as a single agent. Voriconazole produced complete response in four children with invasive aspergillosis and two with hepatosplenic candidiasis, who were unresponsive to L-AMB. The rate of IFI attributable death was 5%.

CONCLUSIONS

Our results indicate that AFP with fluconazole and early empirical antifungal therapy may be effective in reducing the incidence and mortality of IFI in children with acute leukemia.

Nosocomial candidaemia in children: results of a 9-year study

The aim of this study was to determine changes in the incidence of nosocomial candidaemia and to evaluate the risk factors, demographic features, treatment and clinical outcome associated with candidaemia in a Turkish tertiary care paediatric unit within a 9-year period. The data of children who were diagnosed as nosocomial candidaemia, were examined in this study. Between January 1997 and December 2005, a total of 102 nosocomial candidaemia episodes were identified in 102 patients. The rate of nosocomial candidaemia in our clinic increased from 3.2 cases per 1000 admissions in 1997-1999, to 5.5 per 1000 admissions in 2000-2002 and to 6.9 per 1000 admissions in 2003-2005 (P = 0.003). The species most frequently causing candidaemia were Candida albicans (39.2%), Candida parapsilosis (21.6%) and Candida tropicalis (15.7%). The mortality of C. albicans (37.5%), was significantly higher than the mortality of non-albicans species (17.7%) (P = 0.04). Independent risk factors associated with candidaemia-related deaths by logistic regression analysis were disseminated candidiasis (odds ratio, 5.7; P = 0.01), paediatric intensive care unit stay (odds ratio, 8.1; P = 0.001), prolonged antibiotics therapy (odds ratio, 5.2; P = 0.014), use of total parenteral nutrition (odds ratio, 4.4; P = 0.038) and mechanical ventilation (odds ratio, 4.9; P = 0.01). The rate of nosocomial candidaemia in our clinic increased >2-fold during the study period.

Primary invasive aspergillosis of the digestive tract: report of two cases and review of the literature

Background:

Disseminated aspergillosis is thought to occur as a result of vascular invasion from the lungs with subsequent bloodstream dissemination, and portals of entry other than sinuses and/or the respiratory tract remain speculative.

Methods:

We report two cases of primary aspergillosis in the digestive tract and present a detailed review of eight of the 23 previously-published cases for which detailed data are available.

Results and Conclusion:

These ten cases presented with symptoms suggestive of typhlitis, with further peritonitis requiring laparotomy and small bowel segmental resection. All cases were characterized by the absence of pulmonary disease at the time of histologically-confirmed gastrointestinal involvement with vascular invasion by branched Aspergillus hyphae. These cases suggest that the digestive tract may represent a portal of entry for Aspergillus species in immunocompromised patients.

Pathology teach and tell disseminated candidiasis in an infant with acute myeloid leukemia without prior chemotherapy

Opportunistic fungal infections are significant problems for neutropenic patients who are undergoing cytotoxic therapy for acute leukemia. Systemic and hepatosplenic candidiasis have been reported in acute leukemic patients who are on chemotherapy. Gastrointestinal tract involvement is a rare phenomenon in disseminated candidiasis, especially in acute leukemia. We report one such rare case of acute myeloid leukemia in an infant who died of disseminated candidiasis with gastrointestinal tract involvement prior to the institution of chemotherapy.

Effects of acute exercise on neutrophils in pediatric acute lymphoblastic leukemia survivors: a pilot study

PURPOSE

This nonrandomized controlled trial was designed to investigate the effects of acute exercise on neutrophil count and function in children and adolescents receiving maintenance treatment for acute lymphoblastic leukemia (ALL) compared to matched controls.

METHODS

Participants (n = 10; 4 ALL patients and 6 healthy matched controls) were males between the ages of 7 to 18 years. On visit 1, participants completed an incremental exercise test to volitional exhaustion on a treadmill to determine peak aerobic fitness (VO(2peak)). On visit 2, participants completed a 30-minute exercise session consisting of an intermittent run-walk on a treadmill at 70% to 85% of VO(2) peak with blood sampling completed at 5 time points: fasting, preexercise, postexercise, 1-hour postexercise, and 2-hour postexercise.

RESULTS

A significant increase in absolute neutrophil count from preexercise to postexercise was observed in both groups (P = 0.011). Neutrophil oxidative capacity was significantly depressed in the ALL group at the basal level (P = 0.029), however, it increased in both groups after exercise and stimulation.

CONCLUSIONS

This preliminary study suggests that 30 minutes of moderate intensity exercise in ALL patients receiving maintenance therapy provides a similar neutrophil response to that of healthy age and sex-matched controls.

New strategies of antifungal therapy in hematopoietic stem cell transplant recipients and patients with hematological malignancies

Invasive fungal infections (IFIs) are associated with considerable morbidity and mortality among high-risk individuals. Outcomes for IFI historically have been suboptimal and associated with a high mortality rate, hence global prophylaxis strategies have been applied to at-risk populations. Among certain populations, fluconazole prophylaxis has reduced systemic and superficial infections caused by Candida species. Newer azoles are currently being evaluated as prophylaxis and have the potential to provide protection against mould pathogens that are more troublesome to treat once they occur. Global prophylaxis strategies have the shortcoming of subjecting patients to therapy that ultimately will not need it. Targeted prophylaxis has the advantage of treating only patients at highest risk using some parameter of greater host susceptibility. Prophylaxis strategies are most suitable in patients at the highest risk for IFI. For patient groups whose risk is somewhat lower or when suspicion of IFI occurs in patients receiving prophylaxis, empirical antifungal therapy is often employed following a predefined period of fever. Again this approach subjects many non-infected patients to unnecessary and toxic therapy. A more refined approach such as presumptive or pre-emptive therapy whereby treatment is only initiated upon positive identification of a surrogate marker of infection in combination with clinical and radiological signs will subject fewer patients to toxic and expensive treatments.

Pharmacokinetics, safety, and tolerability of caspofungin in children and adolescents

Caspofungin is a parenteral antifungal that inhibits beta-1,3-D-glucan synthesis. Although licensed for adult use, the appropriate caspofungin dosing regimen in pediatric patients is not yet known. We therefore investigated the pharmacokinetics and safety of caspofungin in pediatric patients. Thirty-nine children (ages 2 to 11 years) and adolescents (ages 12 to 17 years) with neutropenia were administered caspofungin using either a weight-based regimen (1 mg/kg of body weight/day) or a body surface area regimen (50 mg/m2/day or 70 mg/m2/day). Plasma samples for caspofungin profiles were collected on days 1 and 4. These results were compared to those from adults treated with either 50 or 70 mg/day for mucosal candidiasis. In children receiving 1 mg/kg/day (maximum, 50 mg/day), the area under the concentration-time curve over 24 h (AUC(0-24)) was significantly smaller (46% after multiple doses) than that observed in adults receiving 50 mg/day (P < 0.001). In children and adolescents receiving 50 mg/m2/day (maximum, 70 mg/day), the AUC(0-24) following multiple doses was similar to that for the exposure in adults receiving 50 mg/day. The AUC(0-24) and concentration trough (at 24 h) in pediatric patients receiving the 50-mg/m2 daily regimen were consistent across the range of ages. Caspofungin was generally well tolerated in this study. None of the patients developed a serious drug-related adverse event or were discontinued for toxicity. These results demonstrate that caspofungin at 1 mg/kg/day in pediatric patients is suboptimal. Caspofungin administration at 50 mg/m2/day provides a comparable exposure to that of adult patients treated with 50 mg/day.

Delaying the empiric treatment of candida bloodstream infection until positive blood culture results are obtained: a potential risk factor for hospital mortality

Fungal bloodstream infections are associated with significant patient mortality and health care costs. Nevertheless, the relationship between a delay of the initial empiric antifungal treatment until blood culture results are known and the clinical outcome is not well established. A retrospective cohort analysis with automated patient medical records and the pharmacy database at Barnes-Jewish Hospital was conducted. One hundred fifty-seven patients with a Candida bloodstream infection were identified over a 4-year period (January 2001 through December 2004). Fifty (31.8%) patients died during hospitalization. One hundred thirty-four patients had empiric antifungal treatment begun after the results of fungal cultures were known. From the time that the first blood sample for culture that was positive was drawn, 9 (5.7%) patients received antifungal treatment within 12 h, 10 (6.4%) patients received antifungal treatment between 12 and 24 h, 86 (54.8%) patients received antifungal treatment between 24 and 48 h, and 52 (33.1%) patients received antifungal treatment after 48 h. Multiple logistic regression analysis identified Acute Physiology and Chronic Health Evaluation II scores (one-point increments) (adjusted odds ratio [AOR], 1.24; 95% confidence interval [CI], 1.18 to 1.31; P < 0.001), prior antibiotic treatment (AOR, 4.05; 95% CI, 2.14 to 7.65; P = 0.028), and administration of antifungal treatment 12 h after having the first positive blood sample for culture (AOR, 2.09; 95% CI, 1.53 to 2.84; P = 0.018) as independent determinants of hospital mortality. Administration of empiric antifungal treatment 12 h after a positive blood sample for culture is drawn is common among patients with Candida bloodstream infections and is associated with greater hospital mortality. Delayed treatment of Candida bloodstream infections could be minimized by the development of more rapid diagnostic techniques for the identification of Candida bloodstream infections. Alternatively, increased use of empiric antifungal treatment in selected patients at high risk for fungal bloodstream infection could also reduce delays in treatment.

Safety, tolerability, and pharmacokinetics of Micafungin (FK463) in febrile neutropenic pediatric patients

Micafungin (FK463) is a new parenteral echinocandin. A multicenter, phase I, open-label, sequential-group dose escalation study was conducted to assess the safety, tolerability, and pharmacokinetics of micafungin in neutropenic pediatric patients. A total of 77 patients stratified by age (2 to 12 and 13 to 17 years) received micafungin. Therapy was initiated at 0.5 mg/kg per day and escalated to higher dose levels of 1.0, 1.5, 2.0, 3.0, and 4.0 mg/kg per day. Micafungin was administered within 24 h of initiating broad-spectrum antibacterial antibiotics for the new onset of fever and neutropenia. The most common overall adverse events in the study population were diarrhea (19.5%), epistaxis (18.2%), abdominal pain (16.9%), and headache (16.9%). Nine patients (12%) experienced adverse events considered by the investigator to be possibly related to the study drug. The most common related events were diarrhea, vomiting, and headache, all occurring in two patients each. There was no evidence of a dose-limiting toxicity as defined within the prespecified criteria of this clinical protocol. There was one death during the study due to septic shock. The pharmacokinetic profiles for micafungin over the 0.5- to 4.0-mg/kg dose range demonstrated dose linearity. Clearance, volume of distribution, and half-life remained relatively constant over the dose range and did not change with repeated administration. The overall plasma pharmacokinetic profile was similar to that observed in adults. However, there was an inverse relation between age and clearance. For patients 2 to 8 years old, clearance was approximately 1.35 times that of patients >/=9 years of age. In summary, micafungin over a dosage range between 0.5 and 4.0 mg/kg/day in 77 febrile neutropenic pediatric patients displayed linear pharmacokinetics and increased clearance as a function of decreasing age.

Acremonium pyomyositis in a pediatric patient with acute leukemia

Invasive Acremonium infection in humans is rare. We report a patient with leukemia who developed pyomyositis due to Acremonium species. Painful cutaneous nodules and severe myalgia were the first clinical manifestations during the neutropenic stage after chemotherapy. Magnetic resonance image (MRI) revealed multiple nodular lesions scattered along the intramuscular regions of the lower legs. Culture of an aspiration grew Acremonium species. Surgical drainage was performed. Although all antifungal agents tested showed no in vitro inhibitory activity, we successfully treated this patient with amphotericin B, granulocyte colony-stimulating factor (G-CSF), and surgical drainage.

Risk factors for invasive aspergillosis in neutropenic patients with hematologic malignancies

Risk factors for invasive aspergillosis (IA) are incompletely identified and may undergo changes due to differences in medical practice. A cohort of 189 consecutive, adult patients with neutropenia hospitalized in the hemato-oncology ward of the University hospital Berne between 1995 and 1999 were included in a retrospective study to assess risk factors for IA. In total, 45 IA cases (nine proven, three probable, 33 possible), 11 patients with refractory fever and 133 controls were analyzed. IA cases had more often acute leukemia or myelodysplastic syndrome (MDS) (88 vs 38%, P < 0.001) and a longer duration of neutropenia (mean 20.6 vs 9.9 days, P < 0.001). They also had fewer neutropenic episodes during the preceding 6 months (mean 0.42 vs 1.03, P < 0.001), that is, confirmed (82%) and probable (73%) IA occurred most often during the induction cycle. A short time interval ( < or = 14 days) between neutropenic episodes increased the risk of IA four-fold (P = 0.06). Bacteremia, however, was not related to the number of preceding neutropenic episodes. Therefore, neutropenic patients with leukemia or MDS have the highest risk of IA. The risk is highest during the first induction cycle of treatment and increases with short-time intervals between treatment cycles.

Risk factors for disseminated candidiasis in children with candidemia

OBJECTIVE

To determine the risk factors for disseminated infection in hospitalized children with candidemia.

METHODS

We performed a nested case-control study within a cohort of hospitalized children with candidemia. The cohort was defined by all patients with positive blood cultures for Candida species in a large, urban, academic, tertiary care children's hospital from 1998 to 2001. Cases were patients with clinical, microbiologic or radiographic evidence of disseminated candidiasis. Controls were patients with no evidence of disseminated candidiasis.

RESULTS

Among 168 total children with candidemia, the median age was 3.5 years (interquartile range, 0.6-14.3). There were 189 episodes of candidemia. Candida species included:Candida albicans (41%), Candida parapsilosis (24%), Candida glabrata (13%) and Candida tropicalis (9%). The most common underlying diagnoses were oncologic (24%), gastrointestinal (15%) and cardiac (10%) diseases. Eighty-nine patients (53%) were admitted to an intensive care unit, 46 (27%) to a general pediatric or surgical ward and 33 (20%) to the oncology ward. Of the 168 patients with candidemia, 153 were included in the analysis of risk factors for disseminated candidiasis. Of 153 (17%) patients, 26 had evidence of organ dissemination. Organ involvement was most commonly identified in the lung (58%), followed by the liver (23%), kidney (16%), brain (12%), spleen (8%), eye (8%) and heart (8%). Eight of the 26 patients had evidence of dissemination to more than 1 organ. Independent risk factors for disseminated candidiasis were persistently positive blood cultures for Candida (>3 days) with a central venous catheter in place (odds ratio, 3.0; 95% confidence interval, 1.2, 7.8; P = 0.02) and immunosuppression (odds ratio, 2.9; 95% confidence interval, 1.2, 7.0; P = 0.02).

CONCLUSIONS

Prolonged duration of candidemia with a central venous catheter in place and immunosuppression were independent risk factors for disseminated candidiasis in children with candidemia. Furthermore review of the epidemiology of candidemia at our institution revealed a heterogeneous population of children at risk for candidemia and a predominance of non-albicans species as the cause of these infections. Future studies are needed to determine the extent of evaluation needed for detecting dissemination among children with candidemia and to explore interventions for its prevention.

Clinical factors associated with fluconazole resistance and short-term survival in patients with Candida bloodstream infection

In a 1-year national surveillance program of Candida bloodstream infections in Japan, clinical factors predicting fluconazole resistance and survival of the patients were analyzed. Blood isolates and complete clinical histories were obtained from 326 patients. Fluconazole-resistant isolates were found in 15 (4.6%) of the cases. Univariate analysis of the demographic and clinical factors associated with fluconazole resistance revealed that age, hematologic malignancy, neutropenia, and immunosuppression were of statistical significance. A multiple logistic regression model showed that only hematologic malignancy as the underlying disease (odds ratio, 6.6; 95% confidence interval, 1.6-26.9; P=0.009) was independently associated with resistance. In 242 cases in which data regarding management and prognosis were available, the 30-day survival rate was 68.4%. In the univariate analysis of factors predicting survival, a significant association was found for Candida species, age of the patient, neutropenia, recent abdominal surgery, removal of the central venous catheter, and use of appropriate antifungal therapy. In the multivariate analysis, removal of the central venous catheter (odds ratio, 6.0; 95% confidence interval, 2.2-16.1; P<0.001) and the use of appropriate therapy (odds ratio, 2.1; 95% confidence interval, 1.1-4.1; P=0.03) were independent factors significantly associated with survival after the diagnosis of Candida bloodstream infection.

Candida infections in children treated with conventional chemotherapy for solid tumors (transplant recipients excluded): The Institut Gustave Roussy Pediatrics Department experience

INTRODUCTION

Advances in medical therapy have greatly improved the survival of children suffering from cancer. Although progress has been made in the eradication of malignant disease there is growing concern for the development of fungal infections in patients treated with chemotherapy.

MATERIALS AND METHODS

We reviewed all episodes of pediatric candidemia that occurred between January 1988 and December 2000. We analyzed the general characteristics of this population, risk factors, microbiology features, treatment, complications, and outcome.

RESULTS

Seventeen cases of candidemia were observed during the 12 years of the study at an estimated incidence of 0.4%. Neutropenia occurred at the onset of infection in 13/17 (76.5%) children. A central venous device was present in all cases. Seventy-seven percent of the infections were caused by Candida albicans and in 85% of patients, yeasts had colonized the gastrointestinal tract. In 9/17 patients visceral dissemination was documented. Overall, in 77% of the episodes the outcome was favorable.

CONCLUSIONS

Candidemia is a rare but severe complication in pediatric oncology. Even if the prognosis is better in children than in adults, Candida septicemia remains of great concern since a high percentage of these infections result in visceral dissemination and mortality is still elevated.

Epidemiology of Candida species infections in critically ill non-immunosuppressed patients

A substantial proportion of patients become colonised with Candida spp during hospital stay, but only few subsequently develop severe infection. Clinical signs of severe infection manifest early but lack specificity until late in the course of the disease, thus representing a particular challenge for diagnosis. Mostly nosocomial, invasive candidiasis occurs in only 1-8% of patients admitted to hospitals, but in around 10% of patients housed in intensive care units where it can represent up to 15% of all nosocomial infections. We review the epidemiology of invasive candidiasis in non-immunocompromised, critically ill patients with special emphasis on disease trends over time, pathophysiology, diagnostic approach, risk factors, and impact. Recent epidemiological data suggesting that the emergence of non-albicans candida strains with reduced susceptibility to azoles, previously linked to the use of new antifungals for empiric and prophylactic therapy in immunocompromised patients, may not have occurred in the critically ill. Management of invasive candidiasis in these patients will be addressed in the December issue of The Lancet Infectious Diseases.

Candida bloodstream infection in neonates

Neonatal candidemia is poorly understood and is a leading cause of nosocomial infectious mortality in the nursery. Prevention of candidemia has been difficult, although a combined approach of antifungal prophylaxis and targeted empirical therapy may eventually reduce morbidity and mortality. Multicenter prospective testing of an integrated approach to early diagnosis of neonatal candidemia using newer molecular techniques is also needed. Candidemia in the infant is cause for prompt removal (or replacement) of central vascular catheters and institution of antifungal therapy. End-organ evaluation is also probably warranted to guide treatment and facilitate prognostication. Given the continuing progress in clinical research infrastructure and development of new diagnostic tests and antifungal agents, substantial improvement in the prevention, diagnosis, and management of neonatal candidemia is plausible over the next decade.

Prolonged survival after invasive aspergillosis: a single-institution review of 11 cases

PURPOSE

To perform a retrospective review of the authors' experience with invasive aspergillosis (IA) in a pediatric population treated with conventional chemotherapy. Case series of IA in the pediatric oncology population are limited but generally report poor overall survival.

METHODS

Medical records were reviewed of all patients receiving conventional chemotherapy for malignant disease who developed IA at Children's Hospital and Regional Medical Center, Seattle, Washington, between January 1, 1995, and January 1, 2002.

RESULTS

During the study period there were 11 cases of IA in pediatric cancer patients treated with conventional chemotherapy. All patients had pulmonary IA; two also had evidence of disseminated disease. All patients underwent diagnostic tissue biopsy. Sixty-four percent required further surgery to excise bulky disease. Medical therapy varied with disease presentation and the overall clinical picture, although prolonged treatment with amphotericin B and itraconazole was the mainstay of therapy. Resolution of clinical disease was seen in 91% of patients. Seventy-three percent received further chemotherapy. The 3-year estimated survival was 82%, with a median follow-up of 32.5 months.

CONCLUSIONS

Early diagnosis and aggressive intervention improve long-term survival from IA in immunocompromised pediatric oncology patients. Aggressive surgical resection, prolonged medical therapy after gross resolution of disease, and chemoprophylaxis during subsequent chemotherapy decrease the likelihood of recurrent IA despite subsequent cytotoxic therapy. The ability to proceed with intensive chemotherapy despite a history of IA may improve long-term survival.

Refractory Aspergillus pneumonia in patients with acute leukemia: successful therapy with combination caspofungin and liposomal amphotericin

BACKGROUND

Pulmonary aspergillosis and other invasive fungal infections (IFIs) commonly complicate the management of patients with acute leukemia. Standard amphotericin-based therapies may be ineffective for many patients and the available salvage agents (itraconazole and caspofungin) are reported to possess only moderate activity against resistant infections. Laboratory evidence suggests a synergistic interaction between amphotericin and caspofungin. The authors treated a group of patients with amphotericin-refractory IFIs with the combination of caspofungin and amphotericin (or liposomal amphotericin).

METHODS

A retrospective evaluation of patients with amphotericin-resistant IFIs was conducted. Diagnosis was based on clinical, radiographic, and when available, microbiologic data. Response to combination antifungal therapy was graded as either favorable or unfavorable. Favorable responses included improvement of both clinical and radiographic signs of fungal pneumonia. All other responses were graded as unfavorable.

RESULTS

Thirty patients were included in this analysis. Twenty-six patients had acute leukemia. Based on recently published criteria, the IFIs were classified as proven in 6 patients, probable in 4 patients, and possible in 20 patients. The median duration and dose of amphotericin monotherapy were 12 days (range, 4-65 days) and 7.8 mg/kg (range, 4.2-66.1 mg/kg), respectively. The median duration of combination therapy was 24 days (range, 3-74 days). Eighteen patients (60%) experienced a favorable antifungal response. Twenty patients with acute leukemia received combination therapy for fungal pneumonias arising during intensive chemotherapy treatments. Favorable responses were observed in 15 of these patients (75%), and antifungal response did not depend on the response of the underlying leukemia. Survival to hospital discharge was significantly better (P < 0.001) in patients having a favorable response. Mild to moderate nephrotoxicity was noted in 50% of patients, necessitating the substitution of liposomal amphotericin. Mild elevation of alkaline phosphatase levels occurred in 30% of patients. Caspofungin was temporarily withheld from one patient who developed moderate but reversible biochemical hepatotoxicity.

CONCLUSIONS

The antifungal combination of caspofungin and amphotericin can be administered safely to high-risk patients with hematologic malignancies. Although an absolute assessment of efficacy is limited by the design of this study, encouraging outcomes were noted for many patients. The authors plan to evaluate this regimen further in a randomized clinical trial.

Fluconazole to prevent yeast infections in bone marrow transplantation patients: a randomized trial of high versus reduced dose, and determination of the value of maintenance therapy

PURPOSE

To determine the optimal dose and duration of fluconazole antifungal prophylaxis therapy in bone marrow transplantation patients.

SUBJECTS AND METHODS

Two hundred and fifty-three pediatric and adult bone marrow transplantation patients were randomly assigned to receive fluconazole 400 mg daily (high dose) or 200 mg daily (low dose) while they were neutropenic. After neutrophil recovery, patients were randomly assigned to receive maintenance therapy with either fluconazole (100 mg daily) or clotrimazole troches (10 mg 4 times daily) until 100 days after transplantation. Patients were monitored until 2 weeks after completion of early prophylaxis and to 100 days after transplantation.

RESULTS

During the early prophylaxis phase, rates of yeast colonization and infections were similar in both treatment groups. By day 50, the incidence of Candida infections in the high-dose group was 4% (95% confidence interval [CI]: 1% to 7%; n = 5), compared with 1% in the low-dose fluconazole group (95% CI: 0% to 3%; n = 1; P = 0.08). During the same period, the incidence of Aspergillus infections was 4% (95% CI: 1% to 7%; n = 5) in the high-dose group and 2% (95% CI: 0% to 4%; n = 2; P = 0.33) in the low-dose group. During the maintenance prophylaxis phase, rates of yeast colonization and superficial infections were similar in the fluconazole and clotrimazole groups. Four patients developed systemic fungal infection in the maintenance phase (1 who received clotrimazole and 3 who received fluconazole).

CONCLUSION

High-dose (400 mg daily) and low-dose (200 mg daily) fluconazole have similar efficacy in reducing the incidence of yeast colonization, superficial infection, and systemic infection in neutropenic pediatric and adult patients undergoing bone marrow transplantation. Rates of yeast colonization after neutrophil recovery were similar in patients treated with fluconazole or clotrimazole.

Risk factors for candidal bloodstream infections in surgical intensive care unit patients: the NEMIS prospective multicenter study. The National Epidemiology of Mycosis Survey

To assess risk factors for development of candidal blood stream infections (CBSIs), a prospective cohort study was performed at 6 sites that involved all patients admitted to the surgical intensive care unit (SICU) for >48 h over a 2-year period. Among 4276 such patients, 42 CBSIs occurred (9.82 CBSIs per 1000 admissions). The overall incidence was 0.98 CBSIs per 1000 patient days and 1.42 per 1000 SICU days with a central venous catheter in place. In multivariate analysis, factors independently associated with increased risk of CBSI included prior surgery (relative risk [RR], 7.3), acute renal failure (RR, 4.2), receipt of parenteral nutrition (RR, 3.6), and, for patients who had undergone surgery, presence of a triple lumen catheter (RR, 5.4). Receipt of an antifungal agent was associated with decreased risk (RR, 0.3). Prospective clinical studies are needed to identify which antifungal agents are most protective and which high-risk patients will benefit from antifungal prophylaxis.

Prophylactic antifungal therapy in the intensive care unit

Antifungal prophylaxis is regularly used during treatment of patients with some cancers, as subgroups with high rates of invasive fungal infections are readily identified; for these patients, prophylaxis has been shown to be of value. High-risk liver transplant recipients also benefit from antifungal prophylaxis. Although the idea of extending this concept to the prevention of candidal infections in the larger population of critically ill patients who are seen in the intensive care unit (ICU) and who do not have neutropenia is attractive, implementation of this strategy is difficult because of the widely varying characteristics of patients in the ICU. Two studies have shown the benefit of such prophylaxis, but the benefit was shown only in selected groups of patients who had an unusually high risk for invasive candidiasis. Although the concept is sound, broad-scale implementation of antifungal prophylaxis would be premature and costly, both financially and with regard to resistance and toxicity. Investigations are needed to define and prove the utility of predictive tools for the identification of patients in the ICU who would benefit from prophylaxis.

The ins and outs of DNA fingerprinting the infectious fungi

DNA fingerprinting methods have evolved as major tools in fungal epidemiology. However, no single method has emerged as the method of choice, and some methods perform better than others at different levels of resolution. In this review, requirements for an effective DNA fingerprinting method are proposed and procedures are described for testing the efficacy of a method. In light of the proposed requirements, the most common methods now being used to DNA fingerprint the infectious fungi are described and assessed. These methods include restriction fragment length polymorphisms (RFLP), RFLP with hybridization probes, randomly amplified polymorphic DNA and other PCR-based methods, electrophoretic karyotyping, and sequencing-based methods. Procedures for computing similarity coefficients, generating phylogenetic trees, and testing the stability of clusters are then described. To facilitate the analysis of DNA fingerprinting data, computer-assisted methods are described. Finally, the problems inherent in the collection of test and control isolates are considered, and DNA fingerprinting studies of strain maintenance during persistent or recurrent infections, microevolution in infecting strains, and the origin of nosocomial infections are assessed in light of the preceding discussion of the ins and outs of DNA fingerprinting. The intent of this review is to generate an awareness of the need to verify the efficacy of each DNA fingerprinting method for the level of genetic relatedness necessary to answer the epidemiological question posed, to use quantitative methods to analyze DNA fingerprint data, to use computer-assisted DNA fingerprint analysis systems to analyze data, and to file data in a form that can be used in the future for retrospective and comparative studies.

The ins and outs of DNA fingerprinting the infectious fungi

DNA fingerprinting methods have evolved as major tools in fungal epidemiology. However, no single method has emerged as the method of choice, and some methods perform better than others at different levels of resolution. In this review, requirements for an effective DNA fingerprinting method are proposed and procedures are described for testing the efficacy of a method. In light of the proposed requirements, the most common methods now being used to DNA fingerprint the infectious fungi are described and assessed. These methods include restriction fragment length polymorphisms (RFLP), RFLP with hybridization probes, randomly amplified polymorphic DNA and other PCR-based methods, electrophoretic karyotyping, and sequencing-based methods. Procedures for computing similarity coefficients, generating phylogenetic trees, and testing the stability of clusters are then described. To facilitate the analysis of DNA fingerprinting data, computer-assisted methods are described. Finally, the problems inherent in the collection of test and control isolates are considered, and DNA fingerprinting studies of strain maintenance during persistent or recurrent infections, microevolution in infecting strains, and the origin of nosocomial infections are assessed in light of the preceding discussion of the ins and outs of DNA fingerprinting. The intent of this review is to generate an awareness of the need to verify the efficacy of each DNA fingerprinting method for the level of genetic relatedness necessary to answer the epidemiological question posed, to use quantitative methods to analyze DNA fingerprint data, to use computer-assisted DNA fingerprint analysis systems to analyze data, and to file data in a form that can be used in the future for retrospective and comparative studies.

Five-year-survey of invasive aspergillosis in a paediatric cancer centre. Epidemiology, management and long-term survival

The epidemiology, management, and long-term survival of invasive aspergillosis was assessed in a prospective, 5-year observational study in 346 unselected paediatric cancer patients receiving dose-intensive chemotherapy for newly diagnosed or recurrent malignancies. Invasive aspergillosis occurred exclusively in the context of haematological malignancies, where it accounted for an incidence of 6.8% (n = 13 of 189). The lung was the primary site in 12 cases, and dissemination was present in three of those. Prior to diagnosis, the overwhelming majority of patients had been profoundly neutropenic for at least 14 days (n = 11 of 13) and were receiving systemic antifungal agents (n = 10 of 13). Clinical signs and symptoms were nonspecific but always included fever. All 11 patients who were diagnosed and treated during lifetime for a minimum of 10 days responded to either medical or combined medical and surgical treatment, and seven were cured (64%). Nevertheless, the overall long-term survival was merely 31% after a median follow-up of 5.68 years after diagnosis. Apart from refractory or recurrent cancer, the main obstacles to successful outcome were failure to diagnose IA during lifetime and bleeding complications in patients with established diagnosis. The frequency of invasive aspergillosis of greater than 15% in paediatric patients with acute myeloblastic leukaemia and recurrent leukaemias warrants the systematic investigation of preventive strategies in these highly vulnerable subgroups.

Documented fungal infections after prophylaxis or therapy with wide spectrum antibiotics: relationship between certain fungal pathogens and particular antimicrobials?

Antibiotics are known to be one of the major risk factors for fungal infection. We investigated whether there was a relationship between particular documented fungal infections and therapeutically or prophylactically administered antimicrobials in 105 patients with fungemia or histologically proven invasive aspergillosis or fusariosis. Out of 105 patients, 82.9% received antimicrobials affecting anaerobic microbial gut flora such as: imipenem, vancomycin, ceftazidime, metronidazole, clindamycin or ampicillin-sulbactam. In addition, 44.5% of patients had received prophylaxis with ofloxacin. 31.5% of Candida albicans fungemias occurred despite empiric therapy with amphotericin B and 21.1% during prophylaxis with azoles. The incidence of C. albicans infections (fungemias) was significantly higher (58.9% vs 33.7%, p<0.04) in patients receiving antibiotics not affecting anaerobic gut flora such as ofloxacin, an aminoglycoside or azithromycin. On the other hand, patients treated with third generation cephalosporins, carbapenems, glycopeptides, and broad spectrum penicillins were more likely to develop proven invasive Aspergillus spp. infection (27.9% vs 5.3%, p<0.001) in comparison to those treated with antimicrobials which preserve anaerobic gut flora.

Amphotericin B lipid complex in pediatric patients with invasive fungal infections

BACKGROUND

Lipid formulations of amphotericin B have been recently introduced for treatment of invasive fungal infections. However, little is known about their role in pediatric populations.

METHODS

We studied the safety and antifungal efficacy of amphotericin B lipid complex (ABLC, Abelcet) in 111 treatment episodes in pediatric patients through an open label, emergency use multicenter study. Patients with invasive fungal infections were enrolled if they had mycoses refractory to conventional antifungal therapy, if they were intolerant of previous systemic antifungal agents or concomitant nephrotoxic drugs or if they had preexisting renal disease.

RESULTS

All 111 treatment episodes were evaluable for safety and 54 were evaluable for efficacy. The mean serum creatinine for the study population did not significantly change between baseline (1.23 +/- 0.11 mg/dl) and cessation of ABLC therapy (1.32 +/- 0.12 mg/dl) during 6 weeks. There were no significant differences observed between initial and end-of-therapy levels of serum potassium, magnesium, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase and hemoglobin. However, there was an increase in mean total bilirubin (3.66 +/- 0.73 to 5.31 +/- 1.09 mg/dl) at the end of therapy (P = 0.054). Among 54 cases fulfilling criteria for evaluation of antifungal efficacy, a complete or partial therapeutic response was obtained in 38 patients (70%) after ABLC therapy. Complete or partial therapeutic response was documented in 56% of cases with aspergillosis (n = 25) and in 81% (n = 27) with candidiasis. Among premature infants (n = 8) and allogeneic marrow recipients (n = 14), response rates were 88 and 57%, respectively. Response was similar in those patients enrolled because of intolerance to previous antifungal therapy or because of progressive infection.

CONCLUSIONS

These data support the use of ABLC for treatment of invasive fungal infections in pediatric patients who are intolerant of or refractory to conventional antifungal therapy.

Fungal colonization and infection in children with acute leukemia and lymphoma during induction therapy

BACKGROUND

Fungal infection represents a growing problem in children with hematologic malignancies. During chemotherapy induced neutropenia, colonization with fungi is considered a major risk factor for subsequent fungal infection. The rates and risk factors for mycotic infections in pediatric oncology patients is undetermined, particularly for centers in developing countries. The aim of this study was to evaluate the rates and risk factors of fungal colonization in children with acute leukemia and lymphoma at one of the major pediatric hematology/oncology centers in Turkey.

PROCEDURE

Fifty-two consecutive children newly diagnosed with acute leukemia and lymphoma during intensive remission induction therapy were evaluated for the occurrence of fungal colonization (defined as at least one positive surveillance culture) and infection.

RESULTS

Thirty-six of the 52 patients (69.2%) were colonized by Candida albicans which was the only fungus isolated from surveillance cultures. There were three (5.8%) proven systemic fungal infections: two cases of candidemia and one case of brain abscess with Aspergillus spp. isolated from tissue. All patients with fungal colonization were receiving prophylactic or curative antibiotics. No significant association was found between type of disease and fungal colonization, but there was a significant association with neutropenia.

CONCLUSIONS

Our findings suggest that there is a high rate of fungal colonization in children receiving remission induction therapy for acute leukemia and lymphoma. Limiting the use of antibiotics and instituting antifungal chemoprophylaxis may decrease the rate, while the early initiation of empiric antifungal therapy in patients with fever and suspected mycotic colonization may increase survival in these patients.