NT5E gene and CD38 protein as potential prognostic biomarkers for childhood B-acute lymphoblastic leukemia.

The risk stratification of B-acute lymphoblastic leukemia (B-ALL) is based on clinical and biological factors. However, B-ALL has significant biological and clinical heterogeneity and 50% of B-ALL patients do not have defined prognostic markers. In this sense, the identification of new prognostic biomarkers is necessary. Considering different cohorts of childhood B-ALL patients, gene (DPP4/CD38/ENTPD1/NT5E) and protein (CD38/CD39/CD73) expressions of ectonucleotidases were analyzed in silico and ex vivo and the association with prognosis was established. In univariate analyses, expression of NT5E was significantly associated with worse progression-free survival (PFS) in bone marrow (BM) samples. In multivariate analyses, Kaplan-Meier analysis, and log-rank test, higher NT5E expression predicted unfavorable PFS in BM samples. Considering minimal residual disease (MRD), higher levels of cellularity were associated with the high NT5E expression at day 8 of induction therapy. In addition, we observed that white blood cells (WBC) of childhood B-ALL patients had more CD38 compared to the same cell population of healthy donors (HD). In fact, MRD > 0.1% patients had higher CD38 protein expression on WBC in comparison to HD. Noteworthy, we observed higher CD38 expression on WBC than blasts in MRD > 0.1% patients. We suggest that NT5E gene and CD38 protein expression, of the ectonucleotidases family, could provide interesting prognostic biomarkers for childhood B-ALL.

Impact of allogeneic stem cell transplantation in childhood and adolescence on quality of adulthood life: A case-control study.

BACKGROUND: Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is associated with late complications that can impair the quality of life (QoL) of patients for years after transplant. The purpose of the present study was to determine the difference in the QoL of adults that underwent allo-HSCT in childhood and adolescence compared with not transplanted adults. METHODS: In this prospective case-control cross-sectional study, we included patients aged ≥18 years that received an allo-HSCT during childhood or adolescence and subsequently survived at least 2 years after transplantation. The control group consisted of blood donors matched for age and sex. QoL assessment was performed using the Short Form-36 (SF-36) Health Survey, Portuguese version 2. RESULTS: Thirty-four transplanted patients and controls were included. 58.8% were male, and the median age at transplant was 13.5 years (range, 4-17 years). The median follow-up was 11.5 years (range, 2.0-23.0 years). The most common late effect was skeletally followed by endocrine complications. Patients with these late complications had the worst QOL in the following dimensions: physical functioning, role physical, bodily pain, general health, and mental health. When compared to the control group, patients had a lower score in two dimensions: physical functioning and role physical. CONCLUSIONS: Although skeletal and endocrine complications of transplant patients in childhood have an impact on physical functioning, most parameters of QoL of these patients in adulthood are similar to healthy individuals of the same age and gender. Early detection and long-term monitoring of late complications can prevent impairment of the QoL.

Influence of different asparaginase formulations in the prognosis of children with acute lymphocytic leukaemia in Brazil: a multicentre, retrospective controlled study.

Our group recently showed that the (ASNase) formulation available in Brazil from 2017 to 2018 when used at the same dose and frequency as the formulation provided previously did not reach the activity considered therapeutic. Based on these, our goal was to assess the impact of these facts on the prognosis of children with ALL at different oncology centers. A multicentre retrospective observational study followed by a prospective follow-up. Patients aged >1 and <18 years in first-line treatment followed up at 10 referral centres, between 2014 and 2018 who received the formulation Leuginase® were identified (Group B). For each patient, the centre registered 2 patients who received ASNase in the presentation of Aginasa® exclusively (Group A). Data collection was registered using (Redcap® ). A total of 419 patients were included; 282 in Group A and 137 in B. Group A had a 3-year OS and EFS of 91·8% and 84·8% respectively, while Group B had a 3-year OS of 83·8% (P = 0·003) and EFS of 76·1% (P = 0·008). There was an impact on 3-year OS and EFS of children who received a formulation. This result highlights the importance of evaluating ASNase and monitoring its activity.

Telomere length in healthy newborns is not affected by adverse intrauterine environments.

Different intrauterine exposures are associated with different metabolic profiles leading to growth and development characteristics in children and also relate to health and disease patterns in adult life. The objective of this work was to evaluate the impact of four different intrauterine environments on the telomere length of newborns. This is a longitudinal observational study using a convenience sample of 222 mothers and their term newborns (>37 weeks of gestational age) from hospitals in Porto Alegre, Rio Grande do Sul (Brazil), from September 2011 to January 2016. Sample was divided into four groups: pregnant women with Gestational Diabetes Mellitus (DM) (n=38), smoking pregnant women (TOBACCO) (n=52), mothers with small-for-gestational age (SGA) children due to idiopathic intrauterine growth restriction (n=33), and a control group (n=99). Maternal and newborn genomic DNA were obtained from epithelial mucosal cells. Telomere length was assessed by qPCR, with the calculation of the telomere and single copy gene (T/S ratio). In this sample, there was no significant difference in telomere length between groups (p>0.05). There was also no association between childbirth weight and telomere length in children (p>0.05). For term newborns different intrauterine environments seems not to influence telomere length at birth.

Epigenetics, hypersensibility and asthma: what do we know so far?

In this review, we describe recent advances in understanding the relationship between epigenetic changes, especially DNA methylation (DNAm), with hypersensitivity and respiratory disorders such as asthma in childhood. It is clearly described that epigenetic mechanisms can induce short to long-term changes in cells, tissues, and organs. Through the growing number of studies on the Origins of Health Development and Diseases, more and more data exist on how environmental and genomic aspects in early life can induce allergies and asthma. The lack of biomarkers, standardized assays, and access to more accessible tools for data collection and analysis are still a challenge for future studies. Through this review, the authors draw a panorama with the available information that can assist in the establishment of an epigenetic approach for the risk analysis of these pathologies.

Antibiotic prophylaxis in acute childhood leukemia: What is known so far?

INTRODUCTION: The treatment of acute lymphoblastic leukemia (ALL) has evolved in recent decades, reaching an overall survival rate close to 90%. Currently, approximately 4% of patients with ALL die from secondary complications of chemotherapy. Among these complications, the most frequent is febrile neutropenia (FN). The treatment of acute myeloid leukemias (AMLs) is even more aggressive, being consequently related to a considerable amount of treatment-related toxicity with a high risk of severe infection and death. METHOD: In order to reduce the infection-related risks in these groups of patients, systemic antibacterial prophylaxis has emerged as a possible approach. RESULTS: Antibiotic prophylaxis during neutropenia periods in those undergoing chemotherapy have .already been proven in adults with acute leukemias (ALs). Among the possible available therapeutic options for bacterial prophylaxis in children with cancer, fluoroquinolones emerged with the most amount of evidence. Within this class, levofloxacin became the best choice. CONCLUSION: Therefore, the use of levofloxacin seems to be indicated in very specific situations: in children who are known to be neutropenic for a long time, secondary to intensive chemotherapy; in children with AL undergoing chemotherapy to induce remission; or in children undergoing hematopoietic stem cell transplantation (HSCT). This article aims to describe recent evidence focusing on antibiotic prophylaxis in children with ALs.

Safety of levofloxacin as an antibiotic prophylaxis in the induction phase of children newly diagnosed with acute lymphoblastic leukemia: an interim analysis of a randomized, open-label trial in Brazil.

BACKGROUND: Despite high cure rates, treatment-related mortality in children with acute lymphoblastic leukemia (ALL) remains significant. About 4% of patients die during remission induction therapy and approximately two-thirds of treatment-related deaths are due to infectious complications. METHODS: From May 2021 to June 2022, children aged one through 18 years, with a recent diagnosis of ALL, admitted to three pediatric oncology centers in Brazil, were enrolled in this multicenter, open-label, randomized, phase 3 clinical trial. Eligible patients were randomly divided into two groups, based on a 1:1 allocation ratio, to receive, or not, levofloxacin as a prophylactic agent during the induction phase. All patients were treated according to the IC-BFM 2009 chemotherapy protocol. Primary endpoints were carbapenemase-producing Enterobacteriaceae (CPE) colonization, Clostridioides difficile diarrhea, and other adverse events related to the use of levofloxacin. The secondary endpoint was febrile neutropenia during induction. The median follow-up was 289 days. RESULTS: Twenty patients were included in this trial, 10 in each group (control and levofloxacin). Mild adverse reactions related to levofloxacin were observed in three patients (30%). Three patients had Clostridioides difficile diarrhea, two in the levofloxacin group and one in the control group (p > 0.99). Only one patient presented colonization by CPE. This patient belonged to the levofloxacin group (p > 0.99). Nine patients presented febrile neutropenia, five in the control group and four in the levofloxacin intervention group (p > 0.99), one patient died due to febrile neutropenia. CONCLUSION: The use of levofloxacin was shown to be safe in the induction phase in children with de novo ALL. The use of this medication did not increase the rate of colonization by CPE nor the rate of diarrhea by C. difficile. All adverse reactions were mild and remitted either spontaneously or after switching medicine administration from oral to intravenous route.

The impact of COVID-19 in children with Sickle Cell Disease: Results of a multicentric registry.

OBJECTIVE: To analyze the outcomes of children with sickle cell disease (SCD) and COVID-19. METHOD: A multicenter prospective study was conducted in five hematological centers from Central and Southeast Brazil, starting in April 2020. The variables recorded include clinical symptoms, diagnostic methods, therapeutic measures, and treatment sites. The clinical repercussions of the infection on the initial treatment and the overall prognosis were also evaluated. RESULTS: Twenty-five unvaccinated children, aged 4 to 17 years, with SCD and a positive SARS-CoV-2 RT-PCR result participated in this study. Patients were classified as SCD types SS (n = 20, 80%) and SC (n = 5, 20%). Clinical characteristics and evolution were similar in both groups (p>0.05), except for the fetal hemoglobin value which was higher among the SC patients (p = 0.025). The most frequent symptoms were hyperthermia (72%) and cough (40%). Three children were admitted to the intensive care unit, all of whom were overweight/obese (p = 0.078). No deaths were observed. CONCLUSIONS: Although SCD leads to specific complications, the results found in this sample suggest that COVID-19 does not seem to carry an increased mortality risk in pediatric patients with this disease.

From H1N1 to COVID-19: What we have seen in children with hemoglobinopathies.

This work aimed to better understand the impact of pandemics of respiratory viruses on children with hemoglobinopathies through a comprehensive review of the literature. MEDLINE, SCIELO, LILACS, and PUBMED were used as data sources to find articles without time period restrictions. Previous observations suggest that patients with hemoglobinopathies are a group especially susceptible to the complications of viral respiratory infections, with greater morbidity and mortality related to them. Within this context, this review found that, during the 2009 H1N1 pandemic, the risk of hospitalization in children and adults increased, especially in patients with a history of complications such as acute chest syndrome. In addition, the Coronavirus Disease 2019 (COVID-19) pandemic appears to have less repercussion among children with hemoglobinopathies compared to adults, similar to what is seen in the general population. In the H1N1 pandemic, patients with hemoglobinopathies behaved as a group more susceptible to complications, with increased morbidity and mortality. However, for COVID-19, the existing data to date on these patients do not show the same clinical impact. Thus, although these children deserve attention in case of infection due to their potential risks, they seem to have a favorable evolution.

Follow our path with asparaginase activity: one technique, but different uses in clinical practice.

Acute lymphoblastic leukemia is the most common childhood malignancy. One of the drugs used in the treatment is Asparaginase, and monitoring of its activity levels enables better outcomes. Since 2018, our laboratory has been working to establish a regular analysis of activity. This implementation allowed to qualify care by detecting silent inactivation and also establishing desensitization as a safe way to overcome the lack of Erwinia. We were able to monitor children aged 0 to 18 years who were being treated with PEG-ASNase. The activity was assessed on days 7 (90 samples) and 14 (52 samples) after ASNase infusions. 142 samples were analyzed. 95.7% reached an adequate activity level (≥ 0.1 IU/mL). Patients treated with ASNase can develop allergic reactions. With the activity monitoring, is possible to circumvent situations like these and implement desensitization protocols for patients who had clinical hypersensitivity without inactivation. Desensitization induces temporary unresponsiveness to drug antigens, allowing the patients to proceed with the prescribed chemotherapy. We have received samples from four patients being treated with different desensitization protocols. Patients tolerated the protocols well. Only one had a grade 2 reaction during the infusion and activity < 0.1 IU/mL, which resulted in the switch to Erwinia. The dose adaptation is a possible and more recent use of ASNase monitoring and we were able to confirm the feasibility of PEG-ASNase desensitization protocols.

COVID-19 in HSCT recipients: a collaborative study of the Brazilian Society of Marrow Transplantation (SBTMO).

In the COVID-19 scenario, patients undergoing hematopoietic stem cell transplantation (HSCT) infected with SARS-CoV-2 may have an increased risk of death. Through a national multicenter study, we aimed to describe the impact of COVID-19 on the survival of HSCT recipients in Brazil. Eighty-six patients with a confirmed diagnosis of SARS-CoV-2 (92% by RT-PCR) were included. There were 24 children and 62 adults receiving an autologous (n = 25) and allogeneic (n = 61) HSCT for malignant (n = 72) and non-malignant (n = 14) disorders. Twenty-six patients died, (10 on autologous (38%) and 16 patients (62%) on allogeneic group). The estimated overall survival (OS) at day 40 was 69%. Adults had decreased OS compared to children (66% vs 79%, p = 0.03). The severity of symptoms at the time of diagnosis, ECOG score, laboratory tests (C-reactive protein, urea values) were higher in patients who died (p < 0.05). In conclusion, HSCT recipients infected with SARS-CoV-2 have a high mortality rate mainly in adults and patients with critical initial COVID-19 presentation. These findings show the fragility of HSCT recipients with SARS-CoV-2 infection. Therefore, the importance of adherence to preventive measures is evident, in addition to prioritizing the vaccination of family members and the HSCT team.

Allergic reactions to asparaginase: retrospective cohort study in pediatric patients with acute lymphoid leukemia.

INTRODUCTION: To assess the frequency of allergic reactions to asparaginase (ASP) and possible risk factors for reactions in a cohort of pediatric patients. METHOD: The study was performed based on retrospective data from patients under acute lymphoid leukemia treatment in a general university hospital located in southern Brazil. Information on patients who used ASP from 2010 to 2017 was collected. Allergic reactions were identified in electronic medical records. RESULTS: Among the 98 patients included in the study, 16 (16.3 %) experienced an allergic reaction to native l-asparaginase (L-ASP). Of the 22 patients (22.4 %) that received only intravenous (IV) administration of l-ASP, 10 (62.5 %) had allergic reactions, while 48 patients (49 %) received intramuscular (IM) administration and 28 (28.6 %) received IV and IM administrations. The occurrence of allergic reactions differed between the groups (p <  0.001), and IV administration was associated with allergic reactions. Association was also observed between the severity of the reaction and the route of administration, with the IM route associated with grade 2 and IV route associated with grade 3. Occurrence of allergic reactions was higher when the commercial formulation of l-ASP, Leuginase®, was used (p =  0.0009 in the analysis per patient and p =  0.0003 in the analysis per administration). CONCLUSIONS: The IV administration and commercial Leuginase® presentation were associated with more allergic reactions in the study population, which corroborates the findings in the literature. The IV route was also associated with higher severity of reactions in the present study.

Flow cytometry as a diagnostic tool in neuroblastoma.

In recent years, there has been an expansion in the use of flow cytometry (FC) immunophenotyping in the diagnosis and monitoring of childhood solid neoplasms. Neuroblastoma (NB), in turn, is the most common extracranial solid tumor in childhood. In the present study, we sought to compare FC and anatomopathological examination (PA) / immunohistochemistry (IHC) of children diagnosed or suspected with NB. The median age was 59 months (minimum 0; maximum 325 months), of these 12 were male (57.1%, 12/21). Forty-eight samples (27 bone marrow (BM), 10 peripheral blood (PB), 8 primary tumors (PT) and 2 liver nodules (HN) and 1 rib fragment (RF)) from 21 patients were evaluated. Twenty-nine samples were from patients with clinical suspicion while 19 samples were from patients with previously confirmed diagnosis. Thirteen samples (7 BM, 5 PT and 1 HN) presented NB when analyzed in FC while 8 (3 BM and 5 PT) samples were positive for NB in the PA/IHC. They were concordant in 88.9% of the cases. No NB cells were identified in any PB. Considering the PA as the gold standard, the FC obtained a sensitivity of 100%, a specificity of 86%, a positive predictive value of 67% and a negative predictive value of 100%. This study demonstrates that FC can be used as a methodology for diagnosis and assessment of NB involvement. In addition, FC has the advantage of allowing a quick diagnosis and accurate classification of the disease, and can also assist in monitoring the treatment.

Epidemiological evaluation and survival of children with acute myeloid leukemia.

OBJECTIVE: This study aims to describe the epidemiological characteristics and survival rates of children with acute myeloid leukemia treated in hospitals in southern Brazil and compare them with international data. METHODS: A multicenter cohort study was conducted with retrospective data collection of all new patients with acute myeloid leukemia under 18 treated at five referral centers in pediatric hematology-oncology in southern Brazil between January 2005 and December 2015. RESULTS: Of the 149 patients with acute myeloid leukemia, 63.0% (n=94) were male. The median age at diagnosis was 10.5 years (range 0-18 years) and 40.3% (n=60) had a white blood cell count below 50,000/mm2. The most common Franco-American-British (FAB) subtype was M3 (n=43, 28.9%). Nine (6.0%) patients had central nervous system disease. In M3 patients, overall survival (OS) was 69.2% and 3-year event-free survival was 67.7%; in non-M3 patients, these rates were 45.3% and 36.7%, respectively. In non-M3 patients, OS was significantly different between transplanted (61.8%) and non-transplanted (38.2%) patients (p=0.031). CONCLUSIONS: These results show a higher prevalence of the Franco-American-British M3 subtype than that reported in the international literature, as well as a decreased OS compared with that of developed countries. Further multicenter Brazilian studies with a larger sample size are encouraged to better understand the characteristics of acute myeloid leukemia, and to improve the treatment and prognosis in this population.

Influence of minimal residual disease by multiparametric flow cytometry at day 15 of induction in risk stratification of children with B-cell acute lymphoblastic leukemia treated at a referral hospital in southern Brazil.

BACKGROUND: The minimal residual disease (MRD) is the most important prognostic factor for acute lymphoblastic leukemia (ALL) in children. This study aimed to investigate the influence of detecting the MRD by the multiparametric flow cytometry (MFC) at day 15 (D15) of the induction on the analysis of the risk group classifications of the different childhood ALL treatment protocols used in a referral hospital in southern Brazil. METHOD: We retrospectively reviewed the medical records of patients with B-cell ALL, aged 1 to 18 years, treated at a hospital from January 2013 to April 2017. MAIN RESULTS: Seventy-five patients were analyzed. Regarding the MRD by the MFC at D15, the analyses showed statistical significance when the MRD was grouped into three categories, < 0.1%, 0.1-10%, and > 10%, with the following distribution: 30.7%, 52.0%, and 17.3%, respectively. There was a significant association between D15 MRD-MFC < 0.1% and the likelihood of dying or relapsing and between D15 MRD-MFC > 10% and the likelihood of dying or relapsing. The cumulative hazard ratio for the relapse of patients with D15 MRD-MFC < 0.1%, 0.1-10%, and > 10% was 19.2%, 59.8%, and 80.1%, respectively. CONCLUSION: Our analysis suggests D15 MRD-MFC < 0.1% as a cut-off point for patients with more favorable outcomes and that the MRD at D15 in risk classifications is particularly useful for the stratification of patients with a more favorable prognosis.

Implementation of the asparaginase activity assessment technique for clinical use: experience of a Brazilian Center.

Acute lymphoid leukemia is a childhood cancer that in high-income countries has event-free survival rates of 80% and global survival rates of 90%. In Brazil these rates are under 70%. This difference may be due to the implementation of supportive care, including the assessment of asparaginase (ASNase) activity. ASNase may cause hypersensitivity reactions and silent drug inactivation. For this reason, ASNase activity monitoring is an essential tool to ensure an effective treatment. Our aim was to implement an ASNase activity measurement technique at a hospital setting. samples from children who were given Escherichia coli-derived ASNase were collected. The results of the analyses conducted in our laboratory Hospital de Clínicas de Porto Alegre were compared to those of two institutions: Centro Infantil Boldrini and University of Munster. 262 samples were assessed. The results of the first analyses were compared with those obtained at Centro Infantil Boldrini and showed an ICC of 0.954. Thirty samples were sent to the University of Munster and presented an ICC was 0.960. Our results, when compared to those of national and international centers, showed an excellent agreement. The study was able to implement an ASNase activity test to monitor the treatment.

Asparaginase: an old drug with new questions.

The long-term outcome of acute lymphoblastic leukemia has improved dramatically due to the development of more effective treatment strategies. L-asparaginase (ASNase) is one of the main drugs used and causes death of leukemic cells by systematically depleting the non-essential amino acid asparagine. Three main types of ASNase have been used so far: native ASNase derived from Escherichia coli, an enzyme isolated from Erwinia chrysanthemi and a pegylated form of the native E. coli ASNase, the ASNase PEG. Hypersensitivity reactions are the main complication related to this drug. Although clinical allergies may be important, a major concern is that antibodies produced in response to ASNase may cause rapid inactivation of ASNase, leading to a worse prognosis. This reaction is commonly referred to as "silent hypersensitivity" or "silent inactivation". We are able to analyze hypersensitivity and inactivation processes by the measurement of the ASNase activity. The ability to individualize the ASNase therapy in patients, adjusting the dose or switching patients with silent inactivation to an alternate ASNase preparation may help improve outcomes in those patients. This review article aims to describe the pathophysiology of the inactivation process, how to diagnose it and finally how to manage it.