Prophylactic antibiotics reduce morbidity due to septicemia during intensive treatment for pediatric acute myeloid leukemia

Retrospective Observational Assessment of the Impact of Cefepime Prophylaxis in Neutropenic Pediatric Patients With Acute Myelogenous Leukemia

BACKGROUND

The potential for cefepime prophylaxis to reduce bloodstream infections (BSIs) in pediatric patients with acute myelogenous leukemia (AML) has been incompletely characterized.

METHODS

A retrospective quasi-experimental study of patients under 21 years of age admitted with AML from 2010 through 2018 at two affiliated pediatric tertiary-care hospitals before and after the adoption of routine cefepime prophylaxis for afebrile AML patients during profound neutropenia.

RESULTS

The rate of BSIs per 1000 neutropenia days was significantly lower in the prophylaxis group than the baseline group (2.6 vs 15.5, incidence rate ratio [IRR] 0.17, 95% CI 0.09-0.32). Interrupted time-series analysis showed that a sharp reduction in BSIs coincided with the implementation of prophylaxis. Bacteremia with viridans group streptococci was frequent in the baseline group but not observed after adopting prophylaxis. Despite the increased use of cefepime, the rate of cefepime-nonsusceptible BSIs per 1000 neutropenia days decreased (1.6 vs 4.1, IRR 0.40, 95% CI 0.16-0.99). The median number of febrile neutropenia episodes per patient also decreased in the prophylaxis group, as did the proportion of patients admitted to the intensive care unit (ICU) (22/51 (43.1%) vs 26/38 (68.4%); risk difference -25.3%, 95% CI -44.4 to -2.8). A trend was observed toward an increased proportion of patients with Clostridioides difficile infection in the prophylaxis group (10/51 (19.6%) vs 3/38 (7.9%); risk difference 11.7%, 95% CI -3.4 to 29.0).

CONCLUSIONS

Cefepime prophylaxis was associated with a significant reduction in BSIs, febrile neutropenia, and ICU admission among pediatric AML patients.

The Influence of the Gut Microbiome in Paediatric Cancer Origin and Treatment

Knowledge of the complexity of the gut microbiota is expanding, and its importance in physiological processes and disease development is widely studied. The aim of this review is to present the most relevant and recent research on the associations between gut microbiota and oncologic disease. Recently, a number of associations between the gut microbiome and neoplasms—regarding tumorigenesis, prognosis and therapeutic efficacy—have been reported. The effects of the gut microbiome on these processes are via the direct and indirect immunomodulating effects of bacteria. Studies have been done mainly in adult populations, where its effect on immunomodulating therapies was unambiguous. In paediatric populations, however, due to the low number of cases and the complex therapeutic approaches, there have been only a few studies. Among them, children with acute lymphoblastic leukaemia were mainly involved. Significant alterations in the abundance of certain bacteria were associated with altered therapeutic responses. Regarding solid tumours, studies with low case numbers have been reported; no significant discoveries have been described so far. In the future, studies with larger cohorts are needed in order to better understand the associations between bacteria and neoplasms and to improve prognosis in the paediatric oncologic population.

Effect of Antibacterial Prophylaxis on Febrile Neutropenic Episodes and Bacterial Bloodstream Infections in Dutch Pediatric Patients with Acute Myeloid Leukemia: A Two-Center Retrospective Study

Bloodstream infections (BSIs), especially those caused by Gram-negative rods (GNR) and viridans group streptococci (VGS), are common and potentially life-threatening complications of pediatric acute myeloid leukemia (AML) treatment. Limited literature is available on prophylactic regimens. We retrospectively evaluated the effect of different antibacterial prophylaxis regimens on the incidence of febrile neutropenic (FN) episodes and bacterial BSIs. Medical records of children (0−18 years) diagnosed with de novo AML and treated at two Dutch centers from May 1998 to March 2021 were studied. Data were analyzed per chemotherapy course and consecutive neutropenic period. A total of 82 patients had 316 evaluable courses: 92 were given with single-agent ciprofloxacin, 138 with penicillin plus ciprofloxacin, and 51 with teicoplanin plus ciprofloxacin. The remaining 35 courses with various other prophylaxis regimens were not statistically compared. During courses with teicoplanin plus ciprofloxacin, significantly fewer FN episodes (43 vs. 90% and 75%; p < 0.0001) and bacterial BSIs (4 vs. 63% and 33%; p < 0.0001) occurred than with single-agent ciprofloxacin and penicillin plus ciprofloxacin, respectively. GNR and VGS BSIs did not occur with teicoplanin plus ciprofloxacin and no bacterial BSI-related pediatric intensive care unit (PICU) admissions were required, whereas, with single-agent ciprofloxacin and penicillin plus ciprofloxacin, GNR BSIs occurred in 8 and 1% (p = 0.004), VGS BSIs in 24 and 14% (p = 0.0005), and BSI-related PICU admissions were required in 8 and 2% of the courses (p = 0.029), respectively. Teicoplanin plus ciprofloxacin as antibacterial prophylaxis is associated with a lower incidence of FN episodes and bacterial BSIs. This may be a good prophylactic regimen for pediatric AML patients during treatment.

Emergency management of fever and neutropenia in children with cancer: A review

INTRODUCTION

Care of pediatric cancer patients is increasingly being provided by physicians in community settings, including general emergency departments. Guidelines based on current evidence have standardized the care of children undergoing chemotherapy or hematopoietic stem cell transplantation (HSCT) presenting with fever and neutropenia (FN).

OBJECTIVE

This narrative review evaluates the management of pediatric patients with cancer and neutropenic fever and provides comparison with the care of the adult with neutropenic fever in the emergency department.

DISCUSSION

When children with cancer and FN first present for care, stratification of risk is based on a thorough history and physical examination, baseline laboratory and radiologic studies and the clinical condition of the patient, much like that for the adult patient. Prompt evaluation and initiation of intravenous broad-spectrum antibiotics after cultures are drawn but before other studies are resulted is critically important and may represent a practice difference for some emergency physicians when compared with standardized adult care. Unlike adults, all high-risk and most low-risk children with FN undergoing chemotherapy require admission for parenteral antibiotics and monitoring. Oral antibiotic therapy with close, structured outpatient monitoring may be considered only for certain low-risk patients at pediatric centers equipped to pursue this treatment strategy.

CONCLUSIONS

Although there are many similarities between the emergency approach to FN in children and adults with cancer, there are differences that every emergency physician should know. This review provides strategies to optimize the care of FN in children with cancer in all emergency practice settings.

Outpatient supportive care for pediatric acute myeloid leukemia: a single institution's experience

Infections are responsible for most treatment-related morbidity and mortality in pediatric acute myeloid leukemia (AML). Children's Oncology Group (COG) recommends hospitalization following chemotherapy until early absolute neutrophil count (ANC) recovery. No standard guidelines exist for antibiotic prophylaxis and discharge practices vary. Our objective was to report our institution's experience with outpatient supportive care management following early discharge. A retrospective chart review of pediatric AML patients treated at our institution from 2010 to 2019 was conducted. Data was collected on length of hospitalization, antibiotics administered, infections, and neutropenia duration. Seventeen patients underwent 60 chemotherapy cycles. All were discharged after completion of chemotherapy if clinically stable. Patients were re-admitted for fever and discharged on empiric antibiotics if afebrile with negative cultures. Prophylactic antibiotics were administered in 55 cycles. There were 12 infections in 11 patients and no deaths due to infection. Patients remained outpatient for a mean of 15.8 neutropenia days per cycle. Outpatient supportive care for children with AML may be feasible and safe. Further studies are needed to establish outpatient supportive care guidelines.

Effectiveness and antimicrobial susceptibility profiles during primary antimicrobial prophylaxis for pediatric acute myeloid leukemia

Limited data are available on antimicrobials exposure and microbiology evolution in pediatric acute myeloid leukemia (AML) patients underwent antimicrobials prophylaxis. To assess the effectiveness of antimicrobials prophylaxis, antibiotic susceptibilities of bacteria, and exposure of antimicrobials during intensive chemotherapy for AML patients, 90 consecutive de novo AML patients aged 0–18 years between January 1, 1997 and March 31, 2018 were enrolled. Vancomycin, ciprofloxacin and voriconazole prophylaxis was administered from January 1, 2010. During the preprophylaxis period, January 1997 to December 2009, 62 patients experienced a total of 87 episodes of bloodstream infection (BSI) and 17 episodes of invasive fungal infection (IFI) among 502 courses of chemotherapy. In contrast, 16 episodes of BSI occurred and no IFIs were reported to occur in 28 patients who received 247 courses of chemotherapy in the prophylaxis period. Patients who received antimicrobial prophylaxis had a significant reduction of BSI, IFI, and febrile neutropenia in comparison with patients without prophylaxis. Exposure to amikacin, carbapenem, amphotericin B was reduced in the prophylaxis period. Imipenem susceptibility of Enterobacter cloacae as well as vancomycin susceptibility of Enterococcus species were reduced in the prophylaxis period. At the time of the last follow up, patients with prophylaxis had a better subsequent 5-year overall survival rate than those without prophylaxis. Prophylactic antimicrobials administration in children with AML who undergo chemotherapy can significantly reduce the rates of life-threatening infection, exposure to antimicrobials, and might result in a better outcome.

How I treat pediatric acute myeloid leukemia

Treatment outcomes for pediatric patients with acute myeloid leukemia (AML) have continued to lag behind outcomes reported for children with acute lymphoblastic leukemia (ALL), in part because of the heterogeneity of the disease, a paucity of targeted therapies, and the relatively slow development of immunotherapy compared to ALL. In addition, we have reached the limits of treatment intensity and, even with outstanding supportive care, it is highly unlikely that further intensification of conventional chemotherapy alone will impact relapse rates. However, comprehensive genomic analyses and a more thorough characterization of the leukemic stem cell have provided insights that should lead to tailored and more effective therapies in the near future. In addition, new therapies are finally emerging, including the BCL-2 inhibitor venetoclax, CD33 and CD123-directed chimeric antigen receptor T cell therapy, CD123-directed antibody therapy, and menin inhibitors. Here we present four cases to illustrate some of the controversies regarding the optimal treatment of children with newly diagnosed or relapsed AML.

Treatment outcomes of pediatric acute myeloid leukemia: a retrospective analysis from 1996 to 2019 in Taiwan

Improvement in outcomes of children with acute myeloid leukemia (AML) is attributed to several refinements in clinical management. We evaluated treatment outcomes of Taiwanese pediatric AML patients in the past 20 years. Overall, 860 de novo AML patients aged 0-18 years and registered in the Childhood Cancer Foundation of R.O.C during January 1996-December 2019 were included. Survival analysis was performed to identify factors that improved treatment outcomes. Regardless of treatment modalities used, patients during 2008-2019 had better 5-year event-free survival (EFS) and overall survival (OS) rates than patients during 1996-2007. For patients received the TPOG-AML-97A treatment, only 5-year OS rates were significantly different between patients diagnosed before and after 2008. Patients with RUNX1-RUNX1T1 had similar relapse-free survival rates, but 5-year OS rates were better during 2008-2019. However, the survival of patients who received hematopoietic stem-cell transplantations (HSCT) did not differ significantly before and after 2008. For patients without relapse, the 5-year OS improved during 2008-2019. Non-relapse mortality decreased annually, and cumulative relapse rates were similar. In conclusion, 5-year EFS and OS rates improved during 2008-2019, though intensities of chemotherapy treatments were similar before and after 2008. Non-relapse mortality decreased gradually. Further treatment strategies including more intensive chemotherapy, novel agents' use, identification of high-risk patients using genotyping and minimal residual disease, early intervention of HSCT, and antibiotic prophylaxis can be considered for future clinical protocol designs in Taiwan.

Levofloxacin for Antibacterial Prophylaxis in Pediatric Patients With Acute Myeloid Leukemia or Undergoing Hematopoietic Stem Cell Transplantation

OBJECTIVE

This study aimed to evaluate the use of levofloxacin for the prevention of bacterial infections in pediatric patients with acute myeloid leukemia or those undergoing hematopoietic stem cell transplantation.

METHODS

This study was a single-center, retrospective review designed to assess the frequency of bacteremia with levofloxacin prophylaxis compared with historical controls that used other, clinician-directed antibacterial prophylaxis. The primary outcome of the study was microbiologically documented bacteremia. Secondary outcomes included febrile neutropenia, clinically documented infection, duration of neutropenia, treatment antibiotic exposure days, Clostridioides difficile infection, and infection-related mortality.

RESULTS

Of the 60 patients included, 24 patients with 32 hospital admissions received levofloxacin and 36 patients with 48 hospital admissions received clinician-directed prophylaxis. There was no difference found in the frequency of bacteremia between levofloxacin and clinician-directed prophylaxis (15.6% vs 10.4%, p = 0.49). There was no difference in the incidence of febrile neutropenia, clinically documented infection, treatment antibiotic exposure days, or 30-day infection-related mortality between the 2 groups. The levofloxacin group had a longer mean duration of neutropenia compared with clinician-directed prophylaxis (26.8 days vs 16.4 days, p = 0.01).

CONCLUSIONS

There was no difference in bacteremia between levofloxacin prophylaxis and clinician-directed prophylaxis in pediatric patients with acute myeloid leukemia or those undergoing hematopoietic stem cell transplantation. Levofloxacin prophylaxis is an appropriate alternative for the prevention of serious bacterial infections in this patient population, although further studies are needed to confirm these results.

Levofloxacin prophylaxis in hospitalized children with leukemia: A cost-utility analysis

BACKGROUND

Infections are common and are a major cause of morbidity and mortality during treatment of childhood leukemia. We evaluated the cost effectiveness of levofloxacin antibiotic prophylaxis, compared to no prophylaxis, in children receiving chemotherapy for acute myeloid leukemia (AML) or relapsed acute lymphoblastic leukemia (ALL).

PROCEDURES

A cost-utility analysis was conducted from the perspective of the single-payer health care system using a lifetime horizon. A comprehensive literature review identified available evidence for effectiveness, safety, costs of antibiotic prophylaxis in children with leukemia, and health utilities associated with the relevant health states. The effects of levofloxacin prophylaxis on health outcomes, quality-adjusted life-years (QALY), and direct health costs were derived from a combined decision tree and state-transition model. One-way deterministic and probabilistic sensitivity analyses were performed to test the sensitivity of results to parameter uncertainty.

RESULTS

The literature review revealed one randomized controlled trial on levofloxacin prophylaxis in childhood AML and relapsed ALL, by Alexander et al, that showed a significant reduction in rates of fever and neutropenia (71.2% vs 82.1%) and bacteremia (21.9% vs 43.4%) with levofloxacin compared to no prophylaxis. In our cost-utility analysis, levofloxacin prophylaxis was dominant over no prophylaxis, resulting in cost savings of $542.44 and increased survival of 0.13 QALY. In probabilistic sensitivity analysis, levofloxacin prophylaxis was dominant in 98.8% of iterations.

CONCLUSIONS

The present analysis suggests that levofloxacin prophylaxis, compared to no prophylaxis, is cost saving in children receiving intensive chemotherapy for AML or relapsed ALL.

Cost-effectiveness of levofloxacin prophylaxis against bacterial infection in pediatric patients with acute myeloid leukemia

BACKGROUND

Infections are the leading cause of therapy-related mortality in pediatric patients with acute myeloid leukemia (AML). Although effectiveness of levofloxacin antibacterial prophylaxis in oncology patients is recognized, its cost-effectiveness is unknown. This study evaluated epidemiologic data regarding levofloxacin use and the cost-effectiveness of this strategy as the cost per bacteremia episode, intensive care unit (ICU) admission, and death avoided in children with AML.

PROCEDURE

A retrospective cohort study using the Pediatric Health Information System (PHIS) database compared demographic and clinical characteristics and receipt of levofloxacin prophylaxis in children with AML admitted for chemotherapy from January 1, 2014, through December 31, 2018. We then developed a decision analysis model in this population that compared costs associated with bacteremia, ICU admission, or death secondary to bacteremia to levofloxacin prophylaxis cost from a healthcare perspective. Time horizon is one chemotherapy cycle. Probabilistic and one-way sensitivity analyses evaluated model uncertainty.

RESULTS

Prophylaxis cost $8491 per bacteremia episode prevented compared with an average added hospital cost of $119 478. Prophylaxis cost $81 609 per ICU admission avoided, compared with an average added hospital cost of $94 181. Prophylaxis cost $220 457 per death avoided. In sensitivity analysis, at a willingness-to-pay threshold of $100 000 per bacteremia episode avoided, prophylaxis remained cost-effective in 94.6% of simulations. Prophylaxis use was more common in recent years in patients with relapsed disease and with chemotherapy regimens considered more intensive.

CONCLUSION

Prophylaxis is cost-effective in preventing bacterial infections in patients with AML. Findings support increased use in patients considered at high risk of bacterial infection secondary to myelosuppression.

Prophylactic piperacillin administration in pediatric patients with solid tumors following different intensities of chemotherapy

BACKGROUND

Prophylactic antibiotics decrease mortality and morbidity in patients with hematological malignancies following intensive chemotherapy. However, the efficacy of prophylactic antibiotics for pediatric patients with solid tumors remains unclear.

METHODS

We retrospectively assessed 103 neutropenic periods from 26 patients with neuroblastoma or brain tumors following three different intensity chemotherapy regimens (05A3, A, and B). While piperacillin was intravenously administered as prophylaxis (PIPC prophylaxis group), the historical control group received no prophylaxis. As patients exhibited a variable degree of myelosuppression based on the intensity of the chemotherapy regimen, we separately evaluated the frequency and severity of febrile neutropenia (FN) in each regimen.

RESULTS

Following intensive chemotherapy, we observed a significantly lower frequency of FN in the PIPC prophylaxis group compared with the historical control group in both regimen 05A3 (20% vs 65%; P = 0.01) and regimen A (56% vs 93%; P = 0.02). We also observed a shorter duration of fever, lower maximum fever, and lower C-reactive protein levels in the PIPC prophylaxis group compared with the historical control group after regimens 05A3 and A. Conversely, the frequency and severity of FN were not different between the two groups after moderate-intensity chemotherapy (regimen B). However, a longitudinal routine surveillance study of Pseudomonas aeruginosa also indicated a reduction in the susceptibility to PIPC throughout the study period.

CONCLUSIONS

Although PIPC prophylaxis might provide an advantage for severe neutropenia in pediatric patients with solid tumors, there is concern regarding bacterial resistance to antibiotics. Therefore, further careful examination is necessary for adaptation.

Pharmacological prophylaxis of infection in pediatric acute myeloid leukemia patients

Introduction: Pediatric patients treated for acute myeloid leukemia (AML) are at high risk of developing severe infectious complications. The choice of an optimum supportive treatment should be based on local epidemiology, as well as intensity and toxicity of the anti-leukemic therapy applied.Areas covered: This review presents an overview of recently published studies focusing on the prevention of infection in pediatric AML patients. PubMed has been systematically searched for clinical trials, reviews, and meta-analyses published in the last 10 years. The focus of this article will be limited to primary prophylaxis only, while secondary prophylaxis is beyond the scope of the current review.Expert opinion: Although anti-bacterial agents may decrease the bacterial infection burden, there is no consensus regarding prophylactic use. To that end, there is a need for further randomized controlled trials to establish the precise role of anti-bacterial prophylaxis in pediatric AML patients. The prophylactic use of anti-fungal agents is strongly recommended for all AML patients. Since the contribution of hematopoietic growth factors to improved survival has not been demonstrated, they should not be routinely applied. Decisions regarding an appropriate prophylactic strategy should be taken in collaboration with the infectious disease experts and pharmacology team.

Effect of radiotherapy on the gut microbiome in pediatric cancer patients: a pilot study

The incidence of pediatric cancer is lower than that of adult cancer worldwide. However, the former has detrimental side effects on the health of individuals, even after the cancer is cured, due to the impact of treatment on development. Recently, correlations have been made between the gut microbiome and cancer in several studies but only on adult participants. There is always a complication of dealing with pediatric cancer treatment protocols because they usually include a combination of chemotherapy, radiotherapy, and intensive prophylactic antibiotics. In the current study, a pilot study was conducted to analyze ten fecal samples from three pediatric cancer patients, suffering from rhabdomyosarcoma near their pelvic region, and two healthy individuals. A correlation between microbial composition and response to treatment was reported, in which the responders had generally a lower microbial diversity compared to non-responders. In addition, nucleotide changes and deletions in the tested 16S rRNA sequences post radiotherapy were detected. Despite the small sample size used in the experiments due to the uncommon rhabdomyosarcoma in children, the results can help in understanding the influence of radiotherapy on the gut microbiome in pediatric cancer patients. More work with larger sample size and different cancer types need to be conducted to understand the influence of radiotherapy on gut microbiome to mitigate the deleterious impact of radiation on treated children.

Immune reconstitution following hematopoietic stem cell transplantation using different stem cell sources

Introduction: Adequate immune reconstitution post-HSCT is crucial for the success of transplantation, and can be affected by both patient- and transplant-related factors. Areas covered: A systematic literature search in PubMed, Scopus, and abstracts of international congresses is performed to investigate immune recovery posttransplant. In this review, we discuss the pattern of immune recovery in the post-transplant period focusing on the impact of stem cell source (bone marrow, peripheral blood stem cells, and cord blood) on immune recovery and HSCT outcome. We examine the impact of serotherapy on immune reconstitution and the need to tailor dosing of serotherapy agents when using different stem cell sources. We discuss new techniques being used particularly with cord blood and haploidentical grafts to improve immune recovery in each scenario. Expert opinion: Cord blood T cells provide a unique CD4+ biased immune reconstitution. Initial studies using targeted serotherapy with cord grafts showed improved immune recovery with limited alloreactivity. Two competing haploidentical approaches have developed in recent years including TCRαβ/CD19 depleted grafts and post-cyclophosphamide haplo-HSCT. Both approaches have comparable survival rates with limited alloreactivity. However, delayed immune reconstitution is still an ongoing problem and could be improved by modified donor lymphocyte infusions from the same haploidentical donor.

Survival and risk factors for mortality in pediatric patients with acute myeloid leukemia in a single reference center in low-middle-income country

Despite advances in therapy and care for children with acute myeloid leukemia (AML), survival rates for children in low- and middle-income countries (LMICs) remain poor. We studied risk factors for mortality and survival in children with AML in a LMIC to develop strategies to improve survival for AML children in these countries. This retrospective cohort (2000-2014) analyzed newly diagnosed AML patients (age < 19 years) at a reference center in Brazil. Demographic and clinical variables were reviewed by AML subtype: acute promyelocytic leukemia (APL), AML with Down syndrome (AML-DS), and other AML subtypes. Cumulative hazard risk for early death (ED) until 6 weeks of treatment and risk factors for mortality were determined by the multivariate Cox hazard models. Survival was assessed for each AML subtypes. A total of 220 patients were diagnosed: APL 50 (22.7%), AML-DS 16 (7.3%), and other AML subtypes 154 (70.0%). The cumulative hazard function values for ED for all patients with AML were 12.5% (95% CI 8.5-18.4%); for each AML patients subtypes: APL, 21.7% (95% CI 11.7-40.5%); AML-DS, 6.2% (95% CI 0.9-44.4%); and other AML subtypes, 10.2% (95% CI 6.2-17.0%). White blood cell count (cutoff 10 × 10⁹/L for APL and 100 × 10⁹/L for other AML subtypes) and Afro-descendance were significant risk factors for mortality in APL and other AML subtypes, respectively. Overall survival for patients with APL, AML-DS, and other AML subtypes was 66.8%, 62.5%, and 38.0%, respectively. APL patients had the highest incidence of ED and those with other subtypes had increased relapse risk. We also observed high rates of death in complete remission mainly due to infection. Better risk classification and identification of risk factors for infection may improve the survival of these patients.

New graft manipulation strategies improve the outcome of mismatched stem cell transplantation in children with primary immunodeficiencies

BACKGROUND

Mismatched stem cell transplantation is associated with a high risk of graft loss, graft-versus-host disease (GvHD), and transplant-related mortality. Alternative graft manipulation strategies have been used over the last 11 years to reduce these risks.

OBJECTIVE

We investigated the outcome of using different graft manipulation strategies among children with primary immunodeficiencies.

METHODS

Between 2006 and 2017, 147 patients with primary immunodeficiencies received 155 mismatched grafts: 30 T-cell receptor (TCR) αβ/CD19-depleted grafts, 43 cord blood (CB) grafts (72% with no serotherapy), 17 CD34⁺ selection with T-cell add-back grafts, and 65 unmanipulated grafts.

RESULTS

The estimated 8-year survival of the entire cohort was 79%, transplant-related mortality was 21.7%, and the graft failure rate was 6.7%. Posttransplantation viral reactivation, grade II to IV acute graft-versus-host disease (aGvHD), and chronic graft-versus-host disease (cGvHD) complicated 49.6%, 35%, and 15% of transplantations, respectively. Use of TCRαβ/CD19 depletion was associated with a significantly lower incidence of grade II to IV aGvHD (11.5%) and cGvHD (0%), although with a greater incidence of viral reactivation (70%) in comparison with other grafts. T-cell immune reconstitution was robust among CB transplants, although with a high incidence (56.7%) of grade II to IV aGvHD. Stable full donor engraftment was significantly greater at 80% among TCRαβ⁺/CD19⁺-depleted and CB transplants versus 40% to 60% among the other groups.

CONCLUSIONS

Rapidly accessible CB and haploidentical grafts are suitable alternatives for patients with no HLA-matched donor. Cord transplantation without serotherapy and TCRαβ⁺/CD19⁺-depleted grafts produced comparable survival rates of around 80%, although with a high rate of aGvHD with the former and a high risk of viral reactivation with the latter that need to be addressed.

Antibiotic prophylaxis in neutropenic children with acute leukemia: Do the presently available data really support this practice?

Antibiotics are frequently administered for prophylaxis of fever in neutropenic children with cancer. This strategy is mainly derived from adults' data, and various pediatric studies evidenced the effectiveness of antibiotics (eg, fluoroquinolones) in the prevention of febrile neutropenia. However, only two pediatric randomized, double-blind, placebo-controlled trials have been performed, with a total of 262 leukemic children enrolled, and no other one was ever powered for analyzing effectiveness over other infectious complications. In an era of increasing antibiotic resistance, the widespread use of antibiotic prophylaxis in neutropenic leukemic children needs to be strongly supported.

Effect of Levofloxacin Prophylaxis on Bacteremia in Children With Acute Leukemia or Undergoing Hematopoietic Stem Cell Transplantation: A Randomized Clinical Trial

Importance

Bacteremia causes considerable morbidity among children with acute leukemia and those undergoing hematopoietic stem cell transplantation (HSCT). There are limited data on the effect of antibiotic prophylaxis in children.

Objective

To determine the efficacy and risks of levofloxacin prophylaxis in children receiving intensive chemotherapy for acute leukemia or undergoing HSCT.

Design, Setting, and Participants

In this multicenter, open-label, randomized trial, patients (6 months-21 years) receiving intensive chemotherapy were enrolled (September 2011-April 2016) in 2 separate groups-acute leukemia, consisting of acute myeloid leukemia or relapsed acute lymphoblastic leukemia, and HSCT recipients-at 76 centers in the United States and Canada, with follow-up completed September 2017.

Interventions

Patients with acute leukemia were randomized to receive levofloxacin prophylaxis for 2 consecutive cycles of chemotherapy (n = 100) or no prophylaxis (n = 100). Those undergoing HSCT were randomized to receive levofloxacin prophylaxis during 1 HSCT procedure (n = 210) or no prophylaxis (n = 214).

Main Outcomes and Measures

The primary outcome was the occurrence of bacteremia during 2 chemotherapy cycles (acute leukemia) or 1 transplant procedure (HSCT). Secondary outcomes included fever and neutropenia, severe infection, invasive fungal disease, Clostridium difficile-associated diarrhea, and musculoskeletal toxic effects.

Results

A total of 624 patients, 200 with acute leukemia (median [interquartile range {IQR}] age, 11 years [6-15 years]; 46% female) and 424 undergoing HSCT (median [IQR] age, 7 years [3-14]; 38% female), were enrolled. Among 195 patients with acute leukemia, the likelihood of bacteremia was significantly lower in the levofloxacin prophylaxis group than in the control group (21.9% vs 43.4%; risk difference, 21.6%; 95% CI, 8.8%-34.4%, P = .001), whereas among 418 patients undergoing HSCT, the risk of bacteremia was not significantly lower in the levofloxacin prophylaxis group (11.0% vs 17.3%; risk difference, 6.3%; 95% CI, 0.3%-13.0%; P = .06). Fever and neutropenia were less common in the levofloxacin group (71.2% vs 82.1%; risk difference, 10.8%; 95% CI, 4.2%-17.5%; P = .002). There were no significant differences in severe infection (3.6% vs 5.9%; risk difference, 2.3%; 95% CI, -1.1% to 5.6%; P = .20), invasive fungal disease (2.9% vs 2.0%; risk difference, -1.0%; 95% CI, -3.4% to 1.5%, P = .41), C difficile-associated diarrhea (2.3% vs 5.2%; risk difference, 2.9%; 95% CI, -0.1% to 5.9%; P = .07), or musculoskeletal toxic effects at 2 months (11.4% vs 16.3%; risk difference, 4.8%; 95% CI, -1.6% to 11.2%; P = .15) or at 12 months (10.1% vs 14.4%; risk difference, 4.3%; 95% CI, -3.4% to 12.0%; P = .28) between the levofloxacin and control groups.

Conclusions and Relevance

Among children with acute leukemia receiving intensive chemotherapy, receipt of levofloxacin prophylaxis compared with no prophylaxis resulted in a significant reduction in bacteremia. However, there was no significant reduction in bacteremia for levofloxacin prophylaxis among children undergoing HSCT.

Antibacterial prophylaxis in pediatric patients with leukemia

BACKGROUND

Bacterial infections in pediatric patients with leukemia are associated with increased risks for morbidity and mortality. Few Recommendations have been made on the use of antibacterial prophylaxis in pediatrics with acute lymphoblastic leukemia (ALL) or acute myeloid leukemia (AML).

OBJECTIVES

To determine the role of antibacterial prophylaxis in pediatric patients with leukemia and the most appropriate regimen that can be safely and effectively used.

METHODS

Literature search was conducted independently by 3 reviewers to find studies on the safety and effectiveness of antibacterial prophylactic regimens.

RESULTS

The search strategy resulted in 13 studies; most of them were observational studies. The available evidence recommends use of antibiotics with Gram-positive bacterial coverage in AML patients. In ALL patients, prophylaxis was used during the intensive phases of chemotherapy with ciprofloxacin being recommended most commonly.

CONCLUSION

Antibacterial prophylaxis mainly with coverage against Gram-positive bacteria is recommended in pediatric patients with AML. For ALL patients, prophylaxis may be considered for patients who are undergoing intensive chemotherapy phases and are at high risk for infections with ciprofloxacin being the most commonly used agent. In general more studies are needed to determine the role of antibacterial prophylaxis in pediatric patients with leukemia.

Adverse Effects of Intravenous Vancomycin-Based Prophylaxis during Therapy for Pediatric Acute Myeloid Leukemia

Children and adolescents with acute myeloid leukemia (AML) are at risk of life-threatening bacterial infections, especially with viridans group streptococci. Primary antibacterial prophylaxis with vancomycin-based regimens reduces this risk but might increase the risks of renal or liver toxicity or Clostridium difficile infection (CDI). A retrospective review of data for patients treated for newly diagnosed AML at St. Jude Children's Research Hospital between 2002 and 2008 was conducted. Nephrotoxicity was classified according to pediatric risk, injury, failure, loss, and end-stage renal disease (pRIFLE) criteria and hepatotoxicity according to Common Terminology Criteria for Adverse Events (CTCAE) criteria. The risks of nephrotoxicity, hepatotoxicity, and CDI were compared between patients receiving vancomycin-based prophylaxis, no intravenous prophylaxis, or other prophylaxis. Generalized linear mixed models were used to address potential confounding. A total of 392 chemotherapy courses (108 with no intravenous prophylaxis, 218 with vancomycin-based prophylaxis, and 66 with other prophylaxis) for 111 patients were included. Development of pRIFLE risk, injury, and failure occurred in 190, 44, and 2 courses, respectively. Increases of at least one, two, and three grades for hepatotoxicity occurred in 189, 52, and 19 courses, respectively. After adjustment for confounders, vancomycin-based prophylaxis was not associated with nephrotoxicity or hepatotoxicity and reduced the risk of CDI, compared to no intravenous prophylaxis (0.9% versus 6.5%; P = 0.007) or other prophylactic regimens (0.9% versus 3.0%; P = 0.23). Despite concerns about vancomycin toxicity, vancomycin-based prophylaxis in pediatric patients with AML did not increase the risk of nephrotoxicity or hepatotoxicity and reduced the risk of CDI. Caution is advised to avoid contributing to antibiotic resistance.

Decreased relapsed rate and treatment-related mortality contribute to improved outcomes for pediatric acute myeloid leukemia in successive clinical trials

BACKGROUND

Outcomes for children with acute myeloid leukemia (AML) have improved over the past 20 years even though the medications used for induction therapy have not changed.

METHODS

This study analyzed data from patients with AML who were enrolled in successive protocols (AML97 and AML02) to determine the contributors to the improved outcomes of the latter clinical trial.

RESULTS

There were significant improvements in 5-year overall survival (48.9% vs 71.2%; P < .0001) and event-free survival (43.5% vs 61.8%; P = .002) from AML97 to AML02. The 5-year cumulative incidence of early death (ED)/treatment-related mortality (TRM) was reduced for patients treated in AML02 (18.5% vs 7.9%; P = .007). Although the overall incidence of refractory disease (6.5% vs 5.6%; P = .736) and relapse (29.3% vs 21.0%; P = .12) did not differ between the 2 studies, patients with low-risk AML who were treated in AML02 had a reduced incidence of relapse (27.3% vs 8.8%; P = .036).

CONCLUSIONS

The improved outcomes of the AML02 trial resulted from improved disease control for low-risk patients and overall decreased ED/TRM. These results emphasize the importance of supportive-care measures throughout chemotherapy courses and hematopoietic cell transplantation and the value of treatment intensity for patients with low-risk AML while underscoring the need for novel therapy, rather than increased therapy intensity, for children with high-risk AML. Cancer 2017;123:3791-3798. © 2017 American Cancer Society.

A Prospective, Holistic, Multicenter Approach to Tracking and Understanding Bloodstream Infections in Pediatric Hematology-Oncology Patients

OBJECTIVE To assess the burden of bloodstream infections (BSIs) among pediatric hematology-oncology (PHO) inpatients, to propose a comprehensive, all-BSI tracking approach, and to discuss how such an approach helps better inform within-center and across-center differences in CLABSI rate DESIGN Prospective cohort study SETTING US multicenter, quality-improvement, BSI prevention network PARTICIPANTS PHO centers across the United States who agreed to follow a standardized central-line-maintenance care bundle and track all BSI events and central-line days every month. METHODS Infections were categorized as CLABSI (stratified by mucosal barrier injury-related, laboratory-confirmed BSI [MBI-LCBI] versus non-MBI-LCBI) and secondary BSI, using National Healthcare Safety Network (NHSN) definitions. Single positive blood cultures (SPBCs) with NHSN defined common commensals were also tracked. RESULTS Between 2013 and 2015, 34 PHO centers reported 1,110 BSIs. Among them, 708 (63.8%) were CLABSIs, 170 (15.3%) were secondary BSIs, and 232 (20.9%) were SPBCs. Most SPBCs (75%) occurred in patients with profound neutropenia; 22% of SPBCs were viridans group streptococci. Among the CLABSIs, 51% were MBI-LCBI. Excluding SPBCs, CLABSI rates were higher (88% vs 77%) and secondary BSI rates were lower (12% vs 23%) after the NHSN updated the definition of secondary BSI (P<.001). Preliminary analyses showed across-center differences in CLABSI versus secondary BSI and between SPBC and CLABSI versus non-CLABSI rates. CONCLUSIONS Tracking all BSIs, not just CLABSIs in PHO patients, is a patient-centered, clinically relevant approach that could help better assess across-center and within-center differences in infection rates, including CLABSI. This approach enables informed decision making by healthcare providers, payors, and the public. Infect Control Hosp Epidemiol 2017;38:690-696.

Bacterial Infections in Children With Acute Myeloid Leukemia Receiving Ciprofloxacin Prophylaxis

BACKGROUND

The aim of the study was to describe the incidence and type of bacterial infections associated with the use of ciprofloxacin prophylaxis as single agent in pediatric patients with acute myeloid leukemia (AML).

PROCEDURE

This was a retrospective review of all patients with AML, who were treated according to the AML02 protocol between 2011 and 2015. The medical records were reviewed for any positive cultures from the initiation of the protocol until death or protocol discontinuation. Patient demographics, type of infections, type of isolated bacteria, and intensive care unit admissions were recorded.

RESULTS

A total of 50 patients were evaluated, who were of a mean age of 8 years±5.1 (SD). We identified 77 episodes of bacterial infections in 42 (84%) patients. Among those bacterial infections, 73 episodes were with bacteremia and included 45 (62%) gram-positive bacterial infections, 24 (33%) gram-negative bacterial infections, and 4 (6%) mixed gram-negative and gram-positive bacterial infections. Coagulase-negative Staphylococcus and Viridans streptococci were the most commonly isolated bacteria in 33% and 30% of the episodes, respectively. Seventeen (45%) patients with bacteremia required intensive care unit admission.

CONCLUSIONS

A high rate of bacterial infection was detected in patients who received the AML02 protocol, mainly gram-positive bacterial infections. The prophylactic regimen should be reconsidered for its efficacy, and other antibacterial prophylaxis may be used.

High Infection-Related Mortality in Pediatric Acute Myeloid Leukemia without Preventive Antibiotics and Antifungals: Retrospective Cohort Study of a Single Center from a Middle-Income Country

OBJECTIVE

This study aimed to evaluate infection-related mortality in patients with acute myeloid leukemia (AML) treated without preventive antibiotics and antifungals in a middle-income country.

MATERIALS AND METHODS

Infection-related mortality was evaluated retrospectively in 49 pediatric patients.

RESULTS

A total of 173 chemotherapy courses were administered as first-line chemotherapy. Four patients died during induction: one patient due to intracranial bleeding, two patients due to typhlitis, and one patient due to invasive fungal infection with pulmonary vascular invasion and massive bleeding. Another two patients died with resistant disease. During consolidation there were four infection-related deaths and one death due to cardiotoxicity. In first-line chemotherapy mortality was 22% (11/49); infection-related mortality was 14% (7/49). Event-free survival and overall survival at 6 years were 42.9% and 61.2% (95% CI: 44-76 and 66-99 months), respectively.

CONCLUSION

Due to considerable infection-related deaths, antibacterial and mold-active antifungal prophylaxis may be tried during neutropenic periods in pediatric AML.

Current Management of Childhood Acute Myeloid Leukemia

The outcome for children with acute myeloid leukemia (AML) has improved significantly over the past 30 years, with complete remission and overall survival rates exceeding 90 and 60%, respectively, in recent clinical trials. However, these improvements have not been achieved by the introduction of new agents. Instead, intensification of standard chemotherapy, more precise risk classification, improvements in supportive care, and the use of minimal residual disease to monitor response to therapy have all contributed to this success. Nevertheless, novel therapies are needed, as the cure rates for many subtypes of childhood AML remain unacceptably low. Here, we briefly review advances in our understanding of the biology and genetics of AML, the results of recent clinical trials, and current recommendations for the treatment of children with AML.

Febrile neutropenia and refeeding syndrome

We describe the management of a 4-year-old child with acute lymphoblastic leukaemia (ALL) who presented with febrile neutropenia, Cryptosporidium and subsequently developed refeeding syndrome. Febrile neutropenia is common and can be life-threatening and we highlight the identification of well low-risk neutropenic children with resolved febrile illnesses suitable for early discharge. We also discuss the potential management strategies for Cryptosporidium Refeeding syndrome is not common, but should be considered as a cause of acute inpatient deterioration and is a significant risk, with potential morbidity, in children who have undergone a period of catabolism. This article reviews the current literature and provides useful guidance on these issues.

Treatment-related adverse events associated with a modified UK ALLR3 induction chemotherapy backbone for childhood relapsed/refractory acute lymphoblastic leukemia

BACKGROUND

The UK ALLR3 (R3) regimen has been adopted to treat pediatric relapsed acute lymphoblastic leukemia (ALL) by many centers in the United States and has become a preferred therapeutic backbone for testing novel agents in clinical trials. A detailed toxicity profile of this platform has not previously been reported. The toxicity and response rates for its use beyond first relapse are unknown.

PROCEDURES

We performed a multi-institutional, retrospective study including children with relapsed ALL treated with the R3 reinduction chemotherapy backbone block 1 across five pediatric centers. Data were extracted from medical records and analyzed.

RESULTS

Fifty-nine patients were included in the study, including 16 patients with ≥2nd relapse. Ninety-seven percent of patients experienced at least one Grade ≥3 nonhematologic adverse event (AE). Grade 3 or higher infection was reported in 90% of patients. Other nonhematologic Grade ≥3 AEs included electrolyte abnormalities, elevation in hepatic enzymes, and pain. Eighty-five percent of patients achieved a complete remission (CR). There were no significant differences in the incidence of AEs, CR rate, and rate of minimal residual disease negativity between patients with 1st or ≥2nd relapse.

CONCLUSION

Our study confirmed that R3 block 1 is a highly active reinduction regimen in childhood relapsed ALL. However, it was associated with a high incidence of severe toxicities, particularly infection. The toxicity profiled in our report should be used to inform optimal supportive care and future clinical trial design with the R3 backbone, particularly when new agents are combined with this regimen.

Antibiotic prophylaxis with teicoplanin on alternate days reduces rate of viridans sepsis and febrile neutropenia in pediatric patients with acute myeloid leukemia

Intensive chemotherapy directed against acute myeloid leukemia of childhood is followed by profound neutropenia and high risk for bacterial and fungal infections, including viridans group streptococci as a common cause for gram-positive septicemia. Few retrospective studies have shown the efficacy of various antibiotic prophylactic regimens in children. We retrospectively studied 50 pediatric patients treated on the AML-BFM 2004 protocol between 2005 and 2015 at St. Anna Children's Hospital and assessed the effect of antibiotic prophylaxis on the frequency of febrile neutropenia and bacterial sepsis. Fifty pediatric patients underwent 199 evaluable chemotherapy cycles. Viridans sepsis occurred after none of 98 cycles with prophylactic administration of teicoplanin/vancomycin in comparison to 12 cases of viridans sepsis among 79 cycles without systemic antibacterial prophylaxis (0 vs. 15 %, p < 0.0001). In addition, there were significantly fewer episodes of febrile neutropenia in the teicoplanin/vancomycin group (44 % vs. no prophylaxis 82 %, p < 0.0001). Severity of infection seemed to be worse when no antibiotic prophylaxis had been administered with a higher rate of intensive care unit treatment (0/98, 0 %, vs. 4/79, 5 %, p = 0.038). So far, no increase of vancomycin-resistant enterococcus isolates in surveillance cultures was noticed. Antibiotic prophylaxis with teicoplanin (or vancomycin) appears safe and feasible and resulted in eradication of viridans sepsis and decreased incidence of febrile neutropenia in pediatric AML patients. The possibility to administer teicoplanin on alternate days on an outpatient basis or at home could contribute to patient's quality of life and decrease health care costs.

Surveillance of bloodstream infections in pediatric cancer centers - what have we learned and how do we move on?

Pediatric patients receiving conventional chemotherapy for malignant disease face an increased risk of bloodstream infection (BSI). Since BSI may represent an acute life-threatening event in patients with profound immunosuppression, and show further negative impact on quality of life and anticancer treatment, the prevention of BSI is of paramount importance to improve and guarantee patients' safety during intensive treatment. The great majority of all pediatric cancer patients (about 85%) have a long-term central venous access catheter in use (type Broviac or Port; CVAD). Referring to the current surveillance definitions a significant proportion of all BSI in pediatric patients with febrile neutropenia is categorized as CVAD-associated BSI. This state of the art review summarizes the epidemiology and the distinct pathogen profile of BSI in pediatric cancer patients from the perspective of infection surveillance. Problems in executing the current surveillance definition in this patient population are discussed and a new concept for the surveillance of BSI in pediatric cancer patients is outlined.

Infectious complications in children with acute myeloid leukemia: decreased mortality in multicenter trial AML-BFM 2004

Infections are an important cause for morbidity and mortality in pediatric acute myeloid leukemia (AML). We therefore characterized infectious complications in children treated according to the trial AML-BFM 2004. Patients with Down syndrome were excluded from the analysis. Data were gathered from the medical records in the hospital where the patients were treated. A total of 405 patients (203 girls; median age 8.4 years) experienced 1326 infections. Fever without identifiable source occurred in 56.1% of the patients and clinically and microbiologically documented infections in 17.5% and 32.4% of the patients, respectively. In all, 240 Gram-positive (112 viridans group streptococci) and 90 Gram-negative isolates were recovered from the bloodstream. Invasive fungal infection was diagnosed in 3% of the patients. Three children each died of Gram-negative bacteremia and invasive aspergillosis, respectively. As compared with the results of AML-BFM 93 with lower dose intensity, infection-related morbidity was slightly higher in AML-BFM 2004 (3.3. versus 2.8 infections per patient), whereas infection-related mortality significantly decreased (1.5% versus 5.4% P=0.003). Specific anti-infective recommendations included in the treatment protocol, regular training courses for pediatric hematologists and increasing experience may be the reason for reduced infection-related mortality in children with AML. Further studies are needed to decrease infection-related morbidity.

Prophylactic levofloxacin in pediatric neutropenic patients during autologous hematopoietic stem cell transplantation

BACKGROUND

Using fluoroquinolone prophylaxis in pediatric neutropenic patients is a controversial issue due to the concern about emergence of resistant strains in addition to the lack of pediatric studies. This study was performed to assess the effectiveness of levofloxacin prophylaxis in pediatric patients during autologous stem cell transplantation.

METHODS

This was an observational study of pediatric patients who underwent autologous stem cell transplantation, comparing patients who received levofloxacin prophylaxis to historical controls.

RESULTS

A total of 96 patients were included (46 patients in the control group and 50 patients received levofloxacin). The median duration till onset of first fever was 11 d in the control group as compared to 15 d in patients who received levofloxacin (p ≤ 0.001). The incidence of infectious complications was higher in patients without levofloxacin (4/46) than those with levofloxacin (1/50). The median duration of empirical antibiotic use was 10 d in the levofloxacin group compared with 14 d in the control group (p < 0.001).

CONCLUSION

Levofloxacin prophylaxis delayed first spike of fever, decreased the incidence of septic complications, and shortened the duration of empiric antibiotic use, but its impact on emergence of resistant organisms should be closely monitored.

Acute lymphoblastic leukemia in low and middle-income countries: disease characteristics and treatment results

PURPOSE OF REVIEW

Acute lymphoblastic leukemia is the most common pediatric cancer. The cure rate of this disease is over 80% in developed countries utilizing protocols with very tolerable toxicity. Several factors contributed to this success, including the implementation of large collaborative clinical trials and the better understanding of disease biology allowing for risk-stratified treatment. We will review the current state of the treatment of acute lymphoblastic leukemia in low-income and medium-income countries.

RECENT FINDINGS

The picture differs from country to country, but recent advances have been made in many countries and the cure rates have improved significantly. Tackling problems such as access to care, abandonment of treatment and toxicity of protocols and the development of centers of excellence are critical for continued improvement. Twinning with programs in developed countries and the creation of regional collaborative groups will allow the implementation of risk-directed therapy and better supportive care.

SUMMARY

The experience in low-income countries shows that a structured approach to the treatment of acute lymphoblastic leukemia results in improved survival.

Preventive antibiotics in pediatric patients with acute myeloid leukemia (AML)

BACKGROUND

Treatment of acute myeloid leukemia (AML) comes with a significant risk of life-threatening infection during periods of prolonged severe neutropenia. We studied the impact of preventive intravenous (IV) antibiotic administration at onset of absolute neutropenia on the incidence and outcome of life-threatening infections during treatment of childhood AML.

PROCEDURES

This is a retrospective study on pediatric patients (aged 0-18 years) consecutively diagnosed with de novo AML and treated at a single institution from April 2005 through February 2013. Patients were treated on the Children's Oncology Group (COG) AAML0531 protocol or with a modified United Kingdom Medical Research Council (UK MRC) AML 10 regimen. Pertinent data were extracted from hard copy or electronic chart review.

RESULTS

A total of 76 chemotherapy phases were analyzed from 29 patients. In each phase reported, preventive antibiotics were initiated when the daily absolute neutrophil count was <500 cells/mcl, before onset of fever. Seven episodes of bacteremia were documented with predominantly coagulase-negative staphylococci and viridans group streptococci. One infection-related death occurred, attributed to progressive respiratory failure occurring months after documented candidal pneumonia.

CONCLUSIONS

Initiation of preventive antibiotics at the onset of absolute neutropenia was associated with no mortality from bacteremia. This preventive approach appears feasible and safe.

Clinical and microbiologic outcomes of quinolone prophylaxis in children with acute myeloid leukemia

BACKGROUND

Intensifying treatment for pediatric acute myeloid leukemia (AML) has improved survival, with infections now being a leading cause of morbidity. Because quinolone prophylaxis is effective in adults with AML and in transplant populations, ciprofloxacin prophylaxis (CPx) was introduced as the standard for pediatric AML. We report here the impact of CPx in this population.

METHODS

Prevalence of fever and neutropenia, frequency and pathogen spectrum of infections, antibiotic use, supportive care and mortality before and after implementation of CPx were retrospectively compared in children with AML.

RESULTS

The cohort included 35 patients with de novo and 10 with relapsed AML, who together underwent 153 chemotherapy courses. Fever and neutropenia resulting in the use of empiric antibiotics occurred in 90% of chemotherapy courses (137/153); this was associated with proven bacteremia in 26%. The use of CPx did not change the incidence of febrile or infectious episodes, number of days of fever or antibiotic treatment or mortality. CPx was associated with a significant decrease in infections caused by Gram-negative rods (13.4% vs 4.7%) but a concomitant significant increase in bacteremia caused by viridans streptococci (12% vs 28%), resulting in no significant overall difference in the incidence of bacteremia between the 2 groups (35.9% vs 31.5%).

CONCLUSIONS

CPx neither alter the incidence of overall bacteremia nor change the pattern of fever or use of supportive care. Our experience supports further investigation into the use of extended-spectrum quinolone prophylaxis during therapy for pediatric AML.

Pediatric acute myeloid leukemia: biology and therapeutic implications of genomic variants

Acute myeloid leukemia (AML) is a molecularly heterogeneous disease and age-associated molecular alterations result in younger children harboring a distinct signature from older children and adolescents. Pediatric AML has a genetic and epigenetic profile with significant differences compared to adult AML. Somatic and epigenetic alterations contribute to myeloid leukemogenesis and can evolve from diagnosis to relapse. Cytogenetic alterations, somatic mutations and response to induction therapy are important in informing risk stratification and appropriate therapy allocation. Next-generation sequencing technologies are providing novel insights into the biology of AML and have the ability to identify potential targets for therapeutic intervention.

Anti-infective prophylaxis in pediatric patients with acute myeloid leukemia

Pediatric patients undergoing treatment for acute myeloid leukemia (AML) are at high risk for infectious complications, predominantly due to Gram-negative bacteria, viridans group streptococci and fungal pathogens. In order to prevent infections in these patients, most institutions have implemented a number of non-pharmacological approaches to supportive care. In addition, antibiotic prophylaxis reduces bacterial infection, but may increase the emergence of resistance. Antifungal prophylaxis is generally recommended for children with AML. Whereas the use of hematopoietic growth factors has not resulted in improved survival, the efficacy of prophylactic granulocyte transfusions has to be determined.

Feasibility, efficacy, and adverse effects of outpatient antibacterial prophylaxis in children with acute myeloid leukemia

BACKGROUND

Intensive chemotherapy for pediatric acute myeloid leukemia incurs the risk of infectious complications, but the benefits of antibiotic prophylaxis remain unclear.

METHODS

In the current study, among 103 children treated on the AML02 protocol between October 2002 and October 2008 at St. Jude Children's Research Hospital, the authors retrospectively assessed the effect of antibiotic prophylaxis on the frequency of febrile neutropenia, clinically or microbiologically confirmed infections (including bacteremia), and antibiotic resistance, as well as on the results of nasal and rectal surveillance cultures. Initially, patients received no prophylaxis or oral cephalosporin (group A). The protocol was then amended to administer intravenous cefepime alone or intravenous vancomycin plus either oral cephalosporin, oral ciprofloxacin, or intravenous cefepime (group B).

RESULTS

There were 334 infectious episodes. Patients in group A had a significantly greater frequency of documented infections and bacteremia (both P < .0001) (including gram-positive and gram-negative bacteremia; P = .0003 and .001, respectively) compared with patients in group B, especially viridans streptococcal bacteremia (P = .001). The incidence of febrile neutropenia without documented infection was not found to be different between the 2 groups. Five cases of bacteremia with vancomycin-resistant enterococci (VRE) occurred in group B (vs none in group A), without related mortality. Two of these cases were preceded by positive VRE rectal surveillance cultures.

CONCLUSIONS

Outpatient intravenous antibiotic prophylaxis is feasible in children with acute myeloid leukemia and reduces the frequency of documented infection but not of febrile neutropenia. Despite the emergence of VRE bacteremia, the benefits favor antibiotic prophylaxis. Creative approaches to shorten the duration of prophylaxis and thereby minimize resistance should be explored.

Development of treatment and clinical results in childhood AML in Austria (1993-2013)

Background

Since the early 1990s, three consecutive pediatric acute myeloid leukemia (AML) trials have been performed in Austria (AML-Berlin-Frankfurt-Münster (BFM) 93, AML-BFM 98, and AML-BFM 2004) in close cooperation with the international BFM study center. Herein, we review the pertinent patient characteristics, therapy, and outcome data.

Patients and methods

From January 1993 to April 2013, 249 children and adolescents (193 protocol patients) diagnosed with AML were enrolled in the three BFM studies. Patients were mainly treated in one of five pediatric hematology/oncology centers distributed over Austria.

Results

Many characteristics and outcome parameters were not statistically different between the three trials. Almost similar proportions of patients were stratified into two risk groups: standard risk (SR) (approximately 37 % overall) and high-risk (HR) (61 %). MLL rearrangements were found in 23 % of patients overall as the most frequent genetic aberration subtype. Complete remission (CR) was achieved by 84-95 % of patients. The most important type of event was leukemic relapse (5-year cumulative incidence 40 ± 8 %, 21 ± 5 %, and 39 ± 6 %; p = 0.058), with a trend to a higher rate specifically in SR patients of study AML-BFM 2004 compared with AML-BFM 98. Importantly, the frequency of death from causes other than relapse sequelae declined over the years (AML-BFM 93: 5/42 12 %, AML-BFM 98: 5/57 9 %, and AML-BFM 2004: 5/94 5 %). Altogether, event-free survival at 5 years varied insignificantly (48 ± 8 %, 61 ± 7 %, and 50 ± 6 %; p = 0.406). Nevertheless, survival (pSU) apparently improved from BFM 93 to subsequent studies, both overall (57 ± 8 %, 75 ± 6 %, and 62 ± 6 %; p = 0.046) and regarding the HR group (5-year-probability of survival (pSU) 40 ± 10 %, 66 ± 8 %, and 52 ± 8 %; p = 0.039).

Conclusion

Treatment of pediatric AML in Austria renders survival rates in the range of international best practice. However, unambiguous statistical comparison of treatment periods is eventually hampered by small numbers and inequalities of recruitment. Hence, only internationally collaborative trials will allow developing treatment further to achieve higher cure rates with fewer events.

Prophylactic first-line antibiotics reduce infectious fever and shorten hospital stay during chemotherapy-induced agranulocytosis in childhood acute myeloid leukemia

BACKGROUND/AIMS

There exists few pediatric data on the safety and efficacy of prophylactic antibiotics during chemotherapy-induced agranulocytosis.

METHODS

We prospectively studied the incidence of infection-related fever in 38 children, aged 2-16 years, with acute myeloid leukemia (AML) over 121 chemotherapy treatment cycles. A prophylactic group (n = 18) was given either vancomycin/cefepime (400 mg/m(2), q12 h/50 mg/kg, q12 h) or piperacillin/tazobactam (110 mg/kg, q12 h). Control patients (n = 20) received no preventive antibiotics.

RESULTS

The prophylactic group (59 treatment cycles) experienced fever less frequently than the control group (0.4 vs. 0.9 events; p < 0.001), had a longer interval between agranulocytosis and fever (6.4 vs. 3.8 days; p = 0.007), had a shorter duration of hospitalization (21.5 vs. 28.5 days; p < 0.001), and had a lower rate of lung infection (38.8 vs. 80.0%; p < 0.001). One patient taking vancomycin experienced a skin rash and 3 patients taking piperacillin/tazobactam had diarrhea; these side effects subsided after antibiotics were discontinued.

CONCLUSIONS

In children with AML, prophylactic antibiotics during the period of chemotherapy-induced agranulocytosis can effectively reduce the incidence of infectious fever and can shorten the average length of hospital stay, improving treatment success and quality of life.

Predictors and outcomes of viridans group streptococcal infections in pediatric acute myeloid leukemia: from the Canadian infections in AML research group

BACKGROUND

Viridans group streptococci (VGS) cause significant morbidity in children treated for acute myeloid leukemia (AML). Our goals were to determine the occurrence and impact of these infections in children treated for AML and to understand the factors that increase the risk of VGS infections and viridans streptococcal shock syndrome (VSSS) in this population.

METHODS

We conducted a retrospective, population-based cohort study that included children ≤18 years of age with de novo AML treated at 15 Canadian centers. We evaluated factors related to VGS infection and VSSS.

RESULTS

Among 341 children with AML, VGS occurred in 78 (22.9%) children over the entire course of therapy and 16 had recurrent episodes. VGS infection occurred in 97 of 1277 courses of chemotherapy (7.6%). VSSS occurred in 19.6% of these episodes and included 11 patients who required intensive care services with 2 VGS infections resulting in death. In multiple regression analysis, factors independently related to VGS included treatment on a Medical Research Council-based protocol (odds ratio (OR) 2.87, 95% confidence interval (CI) 1.53-5.39; P = 0.001), cytarabine dose per gram/m² (OR 1.04, 95% CI 1.01-1.07; P = 0.002) and prolonged neutropenia (OR 1.58, 95% CI: 0.97-2.56; P = 0.06). None of the evaluated factors were predictive of VSSS.

CONCLUSIONS

VGS infections occur in 7.6% of chemotherapy courses and remain an important cause of morbidity and even mortality in children being treated for AML. Interventions to reduce VGS need to be identified.

Antibiotic prophylaxis in children with cancer or who have undergone hematopoietic cell transplantation

Bacterial infections are common in children with cancer and can lead to life-threatening complications. Infections in these patients mainly occur during neutropenic periods, and may be caused by Gram-positive or Gram-negative bacteria. The patients at highest risk of serious infections include those with acute lymphoblastic leukemia (ALL) or acute myeloid leukemia (AML), and those undergoing myeloablative hematopoietic cell transplantation (HCT). This is a review with the main aim of making a critical appraisal of the literature, and summarising what is currently known and can be recommended. The most significant studies support the use of floroquinolones (mainly ciprofloxacin) as the most rational approach to treat pediatric patients with probably long-lasting neutropenia, although trimetoprim-sulphametoxazole and amoxicillin/clavulanate may theoretically be valid alternatives. No prophylaxis seems to be needed for children with cancer without severe neutropenia. However, a global evaluation of the studies of antibiotic prophylaxis in children with cancer indicates that there are not enough data to prepare definite guidelines for its use or avoidance in pediatric oncology, and so further studies are needed. It is not only important to define the best antibiotic regimens for the children in whom such prophylaxis is useful, but also to identify precisely those who do not need it. This would avoid the antibiotic misuse that probably occurs at the moment because many low-risk children with cancer are treated. As prophylaxis against infections requires long-term adherence to an antibiotic regimen, the attitudes and beliefs of stakeholders need to be fully considered.

High frequency of streptococcal bacteraemia during childhood AML therapy irrespective of dose of cytarabine

BACKGROUND

High-dose cytarabine has been associated with a high frequency of viridans group streptococcal (VGS) bacteraemia. VGS bacteraemia causes considerable morbidity and mortality. The Nordic Society of Paediatric Haematology and Oncology (NOPHO)-AML protocols use higher cumulated doses of cytarabine and more chemotherapy series (n = 6) than other protocols with the potential increased risk of severe VGS infections.

PROCEDURE

Medical records of all Danish children enrolled on the NOPHO-AML-2004 protocol between January 2004 and September 2011 (n = 45) were retrospectively reviewed and all febrile episodes were registered.

RESULTS

Following 236 courses of chemotherapy, 112 positive blood cultures were registered. VGS were found in 38% of all positive blood cultures. Infectious episodes with VGS resulted in more days of fever and intravenous antibiotic therapy compared with infections caused by other microorganisms. VGS were involved in 45% of all episodes categorized as sepsis (n = 51) and in 67% of life-threatening bloodstream infections (n = 9). Penicillin resistance was found in 40% of the VGS strains. No significant difference was observed in the proportion of VGS isolated following courses with low-dose cytarabine versus courses with high-dose cytarabine.

CONCLUSIONS

VGS were the most commonly isolated pathogens causing the most severe infections and the majority of life-threatening infections. A substantial proportion of the strains were resistant to penicillin. The high rate of VGS seemed independent of high-dose cytarabine but was more likely caused by the intensive chemotherapy treatment leading to severe mucositis and neutropenia.

Sequential administration of methotrexate and asparaginase in relapsed or refractory pediatric acute myeloid leukemia

BACKGROUND

The efficacy of combination chemotherapy with methotrexate (MTX) and asparaginase is not well known in relapsed and refractory acute leukemia after contemporary therapy.

PROCEDURE

A retrospective study of pediatric patients with relapsed or refractory acute myeloid leukemia (AML) who received MTX and asparaginase as a salvage therapy at St. Jude Children Research Hospital was performed. MTX was given intravenously followed by a dose of asparaginase intramuscularly or intravenously 24 hours later. The chemotherapy cycle was repeated every 7-10 days. Response, survival, and toxicities were evaluated.

RESULTS

Fifteen patients, median age 10.5 years (range, 1.1-18.5 years), were treated. Median number of previous therapeutic regimens was three (range, 1-4). Six patients responded to treatment (three had morphologic complete remission with incomplete blood count recovery, two had partial remission, and one had stable disease for 16 months), and four are still alive. Three of six responders had monoblastic leukemia, and also developed tumor lysis syndrome. The 1- and 2-year overall survival rates are 35.6% and 17.8%, respectively. The most common adverse event was transient elevation of transaminases (nine patients). Two patients developed pancreatitis. Episodes of febrile neutropenia were rare (two patients), and most courses (75 out of 93 total courses) were given in an outpatient setting.

CONCLUSIONS

Combination chemotherapy with MTX and asparaginase appears to be an effective salvage therapy and well tolerated in patients with relapsed or refractory childhood AML, even in those heavily pretreated with contemporary frontline or salvage therapy.

Relapsed childhood acute lymphoblastic leukaemia

With steadily improved cure rates for children with newly diagnosed acute lymphoblastic leukaemia (ALL), treating relapsed ALL has become increasingly challenging largely due to resistance to salvage therapy. Improved biological understanding of mechanisms of relapse and drug resistance, the identification of actionable molecular targets by studying leukaemic cell and host genetics, precise risk stratification with minimum residual disease measurement, and the development of new therapeutic drugs and approaches are needed to improve outcomes of relapsed patients. Molecularly targeted therapies and innovative immunotherapeutic approaches that include specialised monoclonal antibodies and cellular therapies hold promise of enhanced leukaemia cell killing with non-overlapping toxicities. Advances in preparative regimens, donor selection, and supportive care should improve the success of haemopoietic stem-cell transplantation for high-risk patients.