Autologous peripheral blood stem cell mobilization and apheresis in pediatric patients with cancer: A single-center report of 64 procedures.

BACKGROUND: The published experience concerning autologous peripheral blood stem cell collection in children is very limited. METHODS: The data of pediatric patients who underwent autologous stem cell mobilization and apheresis between January 2011 and April 2020 were analyzed retrospectively. RESULTS: We studied retrospectively 64 mobilization and apheresis procedures in 48 pediatric patients (34 males, 14 females), mean age of 7.31 ± 5.38 (range, 1.5-19.7) years, the underlying disease was mostly neuroblastoma (NBL). The body weight of 21 patients (43.75%) was 15 kg or less. The targeted autologous peripheral stem cell apheresis (APSCA) was successfully achieved in 98% of patients. Neuroblastoma patients were younger than the rest of the patients and underwent apheresis after receiving fewer chemotherapy cycles than others and all of them mobilized within the first session successfully. Plerixafor was added to mobilization in nine heavily pretreated patients (18.7%), median two doses (range, 1-4 doses). 11 patients (22.9%) underwent radiotherapy (RT) before mobilization with doses of median 24 Gy (range, 10.8-54.0 Gy). Patients with RT were older at the time of apheresis and had received more chemotherapy courses than patients without RT. As a result, patients with a history of RT had significantly lower peripheral CD34+ cells and CD34+ yields than those without RT. In 17 patients (35.4%), 22 different complications were noted. The most common complications were catheter-related infections (n:10, 20.8%), followed by catheter-related thrombosis in eight patients (16.7%). CONCLUSIONS: Patients who had far less therapy before apheresis were more likely to mobilize successfully. Our study provides a detailed practice approach including complications during APSCA aiming to increase the success rates of apheresis in transplantation centers.

COVID-19 disease in children and adolescents following allogeneic hematopoietic stem cell transplantation: A report from the Turkish pediatric bone marrow transplantation study group.

BACKGROUND: Data on the risk factors and outcomes for pediatric patients with SARS-CoV-2 infection (COVID-19) following hematopoietic stem cell transplantation (HSCT) are limited. OBJECTIVES: The study aimed to analyze the clinical signs, risk factors, and outcomes for ICU admission and mortality in a large pediatric cohort who underwent allogeneic HSCT prior to COVID-19 infection. METHOD: In this nationwide study, we retrospectively reviewed the data of 184 pediatric HSCT recipients who had COVID-19 between March 2020 and August 2022. RESULTS: The median time from HSCT to COVID-19 infection was 209.0 days (IQR, 111.7-340.8; range, 0-3845 days). The most common clinical manifestation was fever (58.7%). While most patients (78.8%) had asymptomatic/mild disease, the disease severity was moderate in 9.2% and severe and critical in 4.4% and 7.6%, respectively. The overall mortality was 10.9% (n: 20). Deaths were attributable to COVID-19 in nine (4.9%) patients. Multivariate analysis revealed that lower respiratory tract disease (LRTD) (OR, 23.20, p: .001) and lymphopenia at diagnosis (OR, 5.21, p: .006) were risk factors for ICU admission and that HSCT from a mismatched donor (OR, 54.04, p: .028), multisystem inflammatory syndrome in children (MIS-C) (OR, 31.07, p: .003), and LRTD (OR, 10.11, p: .035) were associated with a higher risk for COVID-19-related mortality. CONCLUSION: While COVID-19 is mostly asymptomatic or mild in pediatric transplant recipients, it can cause ICU admission in those with LRTD or lymphopenia at diagnosis and may be more fatal in those who are transplanted from a mismatched donor and those who develop MIS-C or LRTD.

Serum interleukin-33 and soluble suppression of tumorigenicity 2 in pediatric leukemia with febrile neutropenia.

The purpose of this study was to evaluate the association between interleukin-33 (IL-33) and its receptor Soluble Suppression of Tumorigenicity-2 (sST2) levels and bacterial infections during febrile neutropenia (FN) in pediatric patients with acute lymphoblastic leukemia (ALL). In this prospective, case-control study, participants were divided into 3 groups: ALL patients with FN (Group A), ALL patients without neutropenia and fever (Group B), and healthy children without infection and chronic disease (Group C). There were 30 cases in each group. Blood samples for IL-33 and sST2 have been drawn from patients in Group A before the initiation of treatment and on days 1 and 5 of treatment, and from patients in Groups B and C at initiation. At admission, mean IL-33 level (39.02 ± 26.40 ng/L) in Group B and mean sST2 level (185.3 ± 371.49 ng/ml) in Group A were significantly higher than the other groups (p = 0.038, p < 0.001, respectively). No difference was observed in the mean IL-33 and sST2 levels in the 5-day follow-up of patients in Group A (p = 0.82, p = 0.86, respectively). IL-33 and sST2 levels were not associated with fever duration, neutropenia duration or length of hospitalization. While C-reactive protein (CRP) was significantly higher in patients with positive blood culture (p = 0.021), IL-33 (p = 0.49) and sST2 (p = 0.21) levels were not associated with culture positivity.  Conclusion: IL-33 and sST2 levels were not found valuable as diagnostic and prognostic markers to predict bacterial sepsis in patients with FN. What is Known: • Neutropenic patients are at high risk of serious bacterial and viral infections, but the admission symptom is often only fever. • Febrile neutropenia has a high mortality rate if not treated effectively. What is New: • Febrile neutropenia is not only caused by bacterial infections. Therefore, new biomarkers should be identified to prevent overuse of antibiotics. • Specific biomarkers are needed to diagnose bacterial sepsis in the early phase of febrile neutropenia.

Monitoring of adenoviremia in pediatric patients undergoing hematopoietic stem cell transplantation: Is it alone sufficient to predict adenoviral disease?

BACKGROUND: We aimed to evaluate our pediatric HSCT recipients routinely monitored for adenoviremia and to determine the adequacy of this monitoring in predicting adenoviral disease (AD). METHODS: A retrospective cohort of patients who underwent allogeneic HSCT between January 2021 and August 2022, and routinely monitored for adenoviremia by real-time PCR was included in our survey. Demographic and clinical data of the patients were recorded. Incidence rates, risk factors, and mortality rates related to adenoviremia, and AD were analyzed. RESULTS: Among 104 HSCTs performed in 94 patients adenovirus (AdV) was revealed in 27 (26%) episodes and adenoviremia in 18 (17.3%) HSCT episodes. AD without adenoviremia developed in nine episodes (8.6%). Disseminated disease was significantly more frequently detected in episodes with adenoviremia (p = .008). GVHD was independent risk factor for AdV detection (OR: 8.6, 95% CI: 2.03-33.7, p = .001). Viremia developed within a shorter time interval after HSCT in isolated episodes of adenoviremia compared to those with concomitant AD (p = .006). Initial and peak viral loads were significantly higher in adenoviremia with AD (p < .001). Mortality was higher in the AdV-detected episodes (p < .001) than in the AdV-undetected episodes. AdV-related mortality was found to be 22.2%. Adenoviremia increased the risk of mortality (OR: 1.2, 95% CI: 0.22-1.33, p = .01). CONCLUSIONS: Adenoviremia monitoring is an important process in the detection of AD. Since some patients may develop AD without accompanying by adenoviremia, monitoring for AdV in blood samples should be supported with other monitoring methods in order to evaluate the probable involvement of different organs or systems.

Acute kidney injury and risk factors in pediatric patients undergoing hematopoietic stem cell transplantation.

BACKGROUND: Acute kidney injury (AKI) is a common complication of hematopoietic stem cell transplantation (HSCT) with increased mortality and morbidity. Understanding the risk factors for AKI is essential. This study aimed to identify AKI incidence, risk factors, and prognosis in pediatric patients post-HSCT. METHODS: We conducted a retrospective case-control study of 278 patients who were divided into two groups: those with AKI and those without AKI (non-AKI). The groups were compared based on the characteristics and clinical symptoms of patients, as well as post-HSCT complications and the use of nephrotoxic drugs. Logistic regression analysis was employed to identify the risk factors for AKI. RESULTS: A total of 16.9% of patients had AKI, with 8.5% requiring kidney replacement therapy. Older age (OR 1.129, 95% CI 1.061-1.200, p < 0.001), sinusoidal obstruction syndrome (OR 2.562, 95% CI 1.216-5.398, p = 0.011), hemorrhagic cystitis (OR 2.703, 95% CI 1.178-6.199, p = 0.016), and nephrotoxic drugs, including calcineurin inhibitors, amikacin, and vancomycin (OR 17.250, 95% CI 2.329-127.742, p < 0.001), were identified as significant independent risk factors for AKI following HSCT. Mortality rate and mortality due to AKI were higher in stage 3 patients than those in stage 1 and 2 AKI (p = 0.019, p = 0.007, respectively). Chronic kidney disease developed in 1 patient (0.4%), who was in stage 1 AKI (2.1%). CONCLUSIONS: AKI poses a serious threat to children post-HSCT, leading to alarming rates of mortality and morbidity. To enhance outcomes and mitigate these risks, it is vital to identify AKI risk factors, adopt early preventive strategies, and closely monitor this patient group.

Effect of Iron Polymaltose Complex Prophylaxis on Frequency of Iron Deficiency and Iron Deficiency Anemia.

OBJECTIVES: To evaluate the effectiveness of national iron prophylaxis policy in 9-12 mo-old infants in Turkey. METHODS: This study was planned as a cross-sectional study, and it included healthy infants aged 9 to 12 mo who presented to the pediatric outpatient clinic for routine check-ups. Parents were interviewed to identify risk factors for iron deficiency (ID) and gather information on Fe+3 - iron polymaltose complex (IPC) prophylaxis usage. Blood samples were collected for hemogram and ferritin analysis. Multiple logistic regression analyses were conducted to determine risk factors for ID and iron deficiency anemia (IDA). RESULTS: The study included 317 infants. In the non-prophylaxis group, the frequency of IDA was 31.1%, compared to 13.4% in the regular prophylaxis group. Iron deficiency was detected in 25% of individuals receiving regular prophylaxis and 13.1% of those without prophylaxis. The risk factors for IDA were insufficient iron diets (OR 2.45, 95% CI: 1.35-4.45) and not receiving Fe+3 - IPC prophylaxis (OR 2.57, 95% CI: 1.24-5.31). The relationship between Fe+3 - IPC prophylaxis and ID did not reach statistical significance (p = 0.253). CONCLUSIONS: Fe+3 - IPC prophylaxis is associated with a lower risk of iron deficiency anemia, but not iron deficiency.

Characteristics and management of hypersensitivity reactions with rabbit anti-thymocyte globulin in pediatric patients.

Background: Anti-thymocyte globulin (ATG) has been successfully used for decades to prevent graft versus host disease before hematopoietic stem cell transplantation (HSCT) as a part of conditioning regimen. However, sometimes hypersensitivity reactions may limit its use. Objective: To evaluate hypersensitivity reactions experienced during rabbit-ATG infusion among children and present successful desensitization protocol. Methods: The medical records of pediatric patients who were given rabbit-ATG treatment at our tertiary center hospital HSCT unit between 2019 and 2022 were reviewed retrospectively. Diagnosis of the patients, age at the time of HSCT, gender, presence of hypersensitivity reaction to rabbit-ATG, and management were evaluated. Characteristics of the reaction and presence of hypersensitivity reaction to other drugs were also noted. If performed, desensitization protocols were evaluated retrospectively. Results: We evaluated 81 patients; 66.6% of them (n = 54) were boys. The mean age of the patients was 8.78 ± 5.48 years. Hypersensitivity to rabbit-ATG was seen in six patients (7.4%). Four of them (4.9%) had anaphylaxis; two (2.4%) had urticaria. Intradermal test performed to every patient before the first dose of ATG infusion was detected a positive result in 1 patient (1.2%) . None of these seven patients had allergic reactions to other drugs before. Successful ATG desensitization was performed in five patients by using a 12-16 step protocol due to patients' reaction severity. Conclusion: This study aimed to evaluate hypersensitivity reactions with rabbit-ATG in children. A successful desensitization protocol with rabbit-ATG is presented. Desensitization must be performed with an experienced team very carefully in the absence of alternative drug.

Central nervous system thrombosis in pediatric acute lymphoblastic leukemia in Turkey: A multicenter study.

BACKGROUND: In patients with acute lymphoblastic leukemia (ALL), the risk of thromboembolism increases due to hemostatic changes secondary to the primary disease and due to treatment-related factors. In this multicenter study, we aimed to research the frequency of central nervous system (CNS) thrombosis occurring during treatment, hereditary and acquired risk factors, clinical and laboratory features of patients with thrombosis, treatment approaches, and thrombosis-related mortality and morbidity rates in pediatric ALL patients. PROCEDURE: Pediatric patients who developed CNS thrombosis during ALL treatment from 2010 to 2021 were analyzed retrospectively in 25 different Pediatric Hematology Oncology centers in Türkiye. The demographic characteristics of the patients, symptoms associated with thrombosis, the stage of the leukemia treatment during thrombosis, the anticoagulant therapy applied for thrombosis, and the final status of the patients recorded through electronic medical records were determined. RESULTS: Data from 70 patients with CNS thrombosis during treatment, out of 3968 pediatric patients with ALL, were reviewed. The incidence of CNS thrombosis was 1.8% (venous: 1.5 %; arterial: 0.03%). Among patients with CNS thrombosis, 47 had the event in the first 2 months. Low molecular weight heparin (LMWH) was the most commonly used treatment with a median of 6 months (min-max: 3-28 months). No treatment-related complications occurred. Chronic thrombosis findings occurred in four patients (6%). In five (7%) patients who developed cerebral vein thrombosis, neurological sequelae (epilepsy and neurological deficit) remained. One patient died related to thrombosis, and the mortality rate was 1.4%. CONCLUSION: Cerebral venous thrombosis and, less frequently, cerebral arterial thrombosis may develop in patients with ALL. The incidence of CNS thrombosis is higher during induction therapy than during other courses of treatment. Therefore, patients receiving induction therapy should be monitored carefully for clinical findings suggestive of CNS thrombosis.

A case series of intracardiac thrombi and vascular involvement in pediatric Behçet's disease.

To evaluate the general characteristics of pediatric Behçet's disease (BD) patients with thrombus and to present the clinical features, treatment responses and prognosis of patients with intracardiac thrombus. The clinical characteristics and outcomes of 15 patients with thrombus among 85 pediatric BD patients followed in the Department of Pediatric Rheumatology were evaluated retrospectively. Of the 15 BD patients with thrombus, 12 (80%) were male, 3 (20%) were female. The mean age at diagnosis was 12.9 ± 1.1 years. Thrombus was present at the time of diagnosis in 12 patients (80%), while thrombus developed in three patients within the first three months after diagnosis. The most common site of thrombus was the central nervous system (n = 9, 60%), followed by deep vein thrombus (n = 6, 40%) and pulmonary artery thrombus (n = 4, 26.6%). Three male patients (20%) developed intracardiac thrombus. The overall intracardiac thrombus rate in the 85 patients was 3.5%. Two of the three patients had thrombus in the right, and one had thrombus in the left heart cavity. In addition to steroids, 2 of the 3 patients received cyclophosphamide, while the patient with thrombus localized in the left heart cavity was given infliximab. In the follow-up, the two patients with thrombus in the right heart cavity were switched to infliximab because of resistance to cyclophosphamide. Complete resolution was observed in 2 of the 3 patients on infliximab; a significant reduction in the thrombus of the other patient was achieved. Intracardiac thrombus is a rare presentation of cardiac involvement in BD. It is usually observed in males and in the right heart. Although steroids and immunosuppressive agents such as cyclophosphamide are recommended as first-line treatment, favorable outcomes can be achieved with anti-TNFs in resistant cases.

A New Perspective for Potential Organ Damage Due to Iron-Mediated Oxidation in Thalassemia Major Patients.

BACKGROUND: The aim of this study is to develop new perspectives to prevent or reduce potential organ damage due to iron-mediated oxidation in thalassemia major patients. METHODS: Seventy patients were included in this study. Blood samples were taken from the patients before and after transfusion. Total thiol, native thiol, disulfide, disulfide/native thiol percentage ratio, ischemia modified albumin (IMA), total antioxidant status (TAS), total oxidant status (TOS), and ferroxidase levels were determined. Additionally, undepleted thiol level (UTL) was determined as a new parameter associated with organ damage. RESULTS: After transfusion, the levels of native thiol, total thiol, disulfide, TAS, ferroxidase, and TOS were higher, while the IMA levels and disulfide/native thiol percent ratio were lower. Significant correlations were found between antioxidant and oxidant tests before and after transfusion. Additionally, a negative correlation was found between the TOS and UTL levels of the patients measured before the transfusion. CONCLUSION: In the present study, transfusion therapy increased both oxidation and the antioxidant levels. In addition, the term UTL has been introduced as a parameter that enables the determination of the oxidation level that may cause potential organ damage in transfusion-dependent thalassemia patients.

Hematopoietic stem cell transplantation activities and HRQOL of refugee or asylum seeker children in Turkey: A multicenter study.

BACKGROUND: Refugee or asylum seekers (RAS) children are at increased risk of physical, developmental, and behavioral health issues. The aim of this study was to evaluate clinical and psychosocial outcomes of hematopoietic stem cell transplantation (HSCT) in RAS children and compare health-related quality of life (HRQOL) to those of Turkish peers. METHODS: This retrospective study included patients who underwent HSCT aged 0-18 years and completed 100-day post-transplant. The PedsQL 4.0 Generic Core Scale was used in children over 5 years old to compare HRQOL. RESULTS: A total of 166 RAS patients (M/F: 106 /60) underwent 174 HSCTs (six patients had two, and one had three HSCT) compared to 66 Turkish patients. The mean age of the patients in the RAS group was 7.8 ± 4.9 years and similar to controls. A total of 124 patients (75%) were from Syria, and 49 (25%) were from other countries in the Middle East and Africa. The cause of migration was war in 121 (74%) RAS patients. Complications of HSCT were no different between the groups. However, the rate of neutropenic sepsis was significantly higher in the RAS group (p = 0.004). The total scores of HRQOL were not different between RAS and controls. In the RAS group, ratings of social functioning were lower in patients with consanguinity or non-malignant disease or who had match-related donors. DISCUSSION: Identifying areas of difficulty in subscales of HRQOL may help physicians to classify patients who need additional supportive care. Regular monitoring and supporting physical needs may result in better functional outcomes after HSCT.

Bone Marrow Grafts From Pediatric Donors May Contain A Considerable Number of Hematogones.

During CD34 + stem cell count to determine the number of stem cells in the allografts from pediatric donors, we noticed a considerable amount of early hematogones (eHGs) within the stem cell gate in flow cytometry. Since the number of hematogones causes a decrease in the total number of stem cells counted within the graft, we planned a retrospective study to analyze the effect of eHGs on transplant outcomes. We also wanted to show how allografts containing high amounts of early HGs affect transplant outcomes. Quantification of CD34 numbers and the number of eHGs were determined by flow cytometry. Patients were divided into 2 groups according to the number of CD 34+ cells calculated after subtracting the number of hematogones within the allograft. Those who received < 2 × 106/kg CD34+ cells and ≥ 2 × 106/kg were defined as group 1 and 2, respectively. Twenty-six patients and their 26 donors were included in the study. The median age of patients was 6.5 years and 5.4 years in Group 1 and 2, respectively. The median donor age was 9 years in Group 1 and 7 years in Group 2. The ages and genders were similar in the two groups (p > 0.05). The number of nucleated cells given to both groups was not different. The number of early hematogones given to both groups was similar (p = 0.93). The mean times to myeloid and platelet engraftments were also similar in the two groups. In this study, we provided trilineage engraftment to all patients in two groups. We could not find a considerable effect of these eHGs in myeloid and platelet engraftments. However, the number of patients included in our study is low, therefore we suggest a study including a large number of donors in order to confirm our findings.

'Trying to catch up with life': The expectations and views of adolescent survivors of childhood acute lymphoblastic leukaemia about long-term follow-up care: A qualitative research.

OBJECTIVE: The aim of this study was to explore adolescent survivors' views and expectations about long-term follow-up care. METHODS: Semi-structured, in-depth interviews were conducted with 16 adolescent survivors of childhood acute lymphoblastic leukaemia. Survivors who had completed treatment at least 2 years ago were involved in the study. Interviews were audio-recorded and transcribed verbatim. An inductive thematic approach was used to analyse the data. RESULTS: Four main themes and sub-themes were identified from the analysis as follows: information needs with three sub-themes 'long-term follow-up, healthy life and social life', support needs with three sub-themes 'psychosocial (peer relations etc.), school related and social-emotional (fear of relapse, body image, self-esteem, etc.)', perceived benefits with two sub-themes 'social-emotional and related to long-term follow-up' and perceived barriers 'medical-hospital related and social life'. CONCLUSIONS: Adolescent survivors mainly need support in terms of psychosocial aspects: self-esteem-body image, school, peer relations and social activities during follow-up. Identified barriers related to follow-up were school absence and not able to participate social activities. Adolescents specify health promotion approaches as benefits aspects of follow-up. The findings of this study will guide nurses in the long-term follow-up care of adolescent survivors of acute lymphoblastic leukaemia and provide an opportunity to plan individualised follow-up care.

Evaluation of coagulation parameters and impact of transfusion on coagulation in patients with beta thalassemia major.

There have been several studies that have shown that patients with beta thalassemia major are at a higher risk of thrombosis due to the procoagulant activity of thalassemic erythrocytes, decreased liver synthetic function, increased platelet activity and vascular endothelial activation attributed to chronic oxidative stress, although there are no established tests to predict thrombotic risk in TM patients. In this study, we evaluated whether or not the platelet function analyser (PFA-200) and thrombin generation test (TGT) would be useful tools to identify hypercoagulability and risk of thrombosis in thalassemia major patients. The study included 50 patients with thalassemia major and 104 healthy control group. Pretransfusion and posttransfusion PFA-200 and TGT results were compared with control group. We found that median C/ADP and C/EPI values in the thalassemia major group were greater in both the pre and posttransfusion samples than the C/ADP and C/EPI results from the control group. The TGT results showed there was no difference between control group and the results from the thalassemia major group. The TGT and PFA-200 testing did not identify hypercoagulability nor identify clear testing parameters to predict a thalassemia major patient's risk of thrombosis. There may be other mechanisms/causes yet unidentified that could better explain thalassemia major patient's increased risk from thromboembolic events.

Clinical Profile and Outcomes of Primary Immunodeficiency and Malignancy in Childhood at a Tertiary Oncology Center in Developing Country.

Primary immune deficiencies are a group of heterogenous genetic disorders characterized by frequent infections, autoimmunity and malignancy. In this study, we aimed to evaluate clinical characteristics, outcomes of children with malignancy developed on background of primary immunodeficiency and compare survival rates of patients between malignant lymphoma with primary immunodeficiency and without immunodeficiency from tertiary oncology center in a developing country. A total 23 patients with primary immunodeficiency and malignancy were evaluated retrospectively. A total of 26 malignancies (first or second) in 23 patients were determined. The median age at the time of the first malignancy was 8 years (ranges 2-18 years) with increased male ratio (M/F:14/9). Non-Hodgkin lymphoma (n = 17; 65%) was the most common malignancy, followed by Hodgkin lymphoma (n = 5), anaplastic ependymoma (n = 1), spinal glioblastoma multiforme (n = 1), retinoblastoma (n = 1) and intracranial hemangiopericytoma (n = 1). The median follow-up time of patients was 25 months (ranges between 1 and 189 months). The 5-year overall survival rate of patients with malignant lymphoma associated with primary immunodeficiency (41%) were lower than immunocompetent patients with malignant lymphoma (80%) (p = 0.000). The 5-year overall survival of patients was diagnosed between 2021 and 2013 years (62%) was higher than previous years (22%) (p = 0.03). In conclusion, non-Hodgkin lymphomas were the most common histopathologic type in patients with malignancy associated with primary immunodeficiency in the present study. The survival of patients with malignant lymphoma associated with primary immunodeficiency has improved in recent years, yet it is still lower than immunocompetent patients with lymphoma and new targeted drugs are required for better survival rates.

Role of therapeutic drug monitoring of intravenous Busulfan for prevention of sinusoidal obstructive syndrome in children.

BACKGROUND: Therapeutic drug monitoring (TDM) of intravenous busulfan (Bu) has been recommended for safe engraftment and decreased toxicity in children undergoing hematopoietic stem cell transplantation (HSCT). This study aims to compare HSCT-related outcomes, such as acute or chronic graft-versus-host disease (GvHD), sinusoidal obstructive syndrome (SOS), event-free survival (EFS), and overall survival (OS) in children with and without TDM for busulfan. METHODS: This retrospective study conducted between February 2012 and February 2021 at our Bone Marrow Transplantation Unit included 172 patients (34% girls) with a median age of 4.70 years (IQR 2.41-10.01). Group A consisted of 46 patients whose Bu doses were adjusted according to actual body weight, and group B consisted of 126 patients whose Bu dose adjustments made according to TDM. RESULTS: Totally, 32 patients (19%) developed moderate or severe SOS. The incidence of SOS was significantly higher in the group without TDM (29% vs. 15%, p = .041). A multivariable analysis showed that the presence of acute GvHD and one alkylating drug-containing conditioning regimen compared with two or three were associated with SOS (p = .03 and p = .002, respectively). In patients with TDM, cumulative Bu dose and area under curve also were not associated with SOS. Other HSCT-related outcomes such as acute or chronic GvHD, relapse and graft rejection rates, OS and EFS rates did not differ between the groups. CONCLUSIONS: TDM and making dose adjustments with Bayesian forecasting over four days of Bu therapy optimizes exposure and reduces the risk of SOS in children undergoing HSCT.

Reliability and validity of the Turkish version of the Paediatric Cancer Coping Scale (PCCS).

BACKGROUND: To determine the validity and reliability of the Turkish version of the Paediatric Cancer Coping Scale, a scaling tool that has three subscales (cognitive coping, problem-oriented coping and defensive coping) and was developed to examine the coping strategies of children with a cancer diagnosis. DESIGN: This psychometric evaluation study focused on validity and reliability assessment of a scale between November 2018 and May 2019. METHODS: Study sample consisted of 165 children with cancer aged 7- to 18-years followed up in the outpatient clinics of a children's hospital. The retest sample consisted of 85 children. Data were collected using a Descriptive Characteristics Form and the Turkish version of the Paediatric Cancer Coping Scale. Cronbach's alpha coefficient and total item correlation were calculated for internal consistency reliability. Exploratory and confirmatory factor analyses were conducted to determine construct validity. RESULTS: The total Cronbach's alpha (α) of the Turkish version of the Paediatric Cancer Coping Scale was 0.77. According to exploratory factor analysis, the Paediatric Cancer Coping Scale has three subscales (cognitive coping, problem-oriented coping and defensive coping). Our results showed a positive and statistically significant correlation between the scale total, cognitive coping and problem-oriented coping scores (p < 0.01). CONCLUSION: The Turkish version of the Paediatric Cancer Coping Scale is a valid and reliable measurement tool that can be used to assess coping styles in paediatric cancer patients. SUMMARY STATEMENT: What is already known about this topic? There is no measurement tool in Turkey to examine coping skills of children with a cancer diagnosis. The number of children diagnosed with cancer is increasing day by day. The children who use coping methods effectively during the disease may be better adapted to treatment. What this paper adds? This study is used to define coping skills of children diagnosed with cancer. Defining the level of children's coping with cancer can enable the child to be guided to receive psychosocial support. The implications of this paper Once the coping skills/levels of children can be measured, those who need help/assistance can be helped. This study will help nurses to identify coping levels of children with a cancer diagnosis. Nurses will be able to evaluate the psychosocial status of children using an objective measurement tool and make a care plan.

Evaluation of early-onset cardiotoxic effects of anthracyclines used during the treatment of childhood acute lymphoblastic leukemia by speckle-tracking echocardiography.

OBJECTIVE: Anthracyclines are widely used in the treatment of acute lymphoblastic leukemia (ALL). However, cardiotoxicity is the most critical side effect that requires dose limitation. It is thought to occur at first exposure, but the clinical presentation may occur years later. In this study, we aimed to determine the time of initial damage and cardiotoxicity that develops in children with ALL. METHODS: In this prospective study, 13 patients with newly diagnosed intermediate-risk precursor B cell ALL treated with the ALL-IC BFM 2009 protocol were included. Conventional echocardiography, tissue Doppler imaging (TDI), and speckle-tracking echocardiography (STE) were performed in all the patients before chemotherapy, after completing the induction phase, and at the end of the reinduction phase. RESULTS: The mean age of the patients was 7.8±4.6 (3.1-16.3) years. Myocardial velocity during systole (Sm) determined by TDI at the interventricular septum significantly decreased during the induction phase. Despite a decrease in STE parameters, a statistically significant reduction was determined in the global longitudinal strain rate at both left and right ventricles at the end of the induction. Nevertheless, a statistically significant increase was observed among the conventional echocardiographic findings in the left ventricular end-diastolic diameter at the end of the reinduction. CONCLUSION: During the treatment of ALL, subclinical anthracycline-associated cardiotoxicity develops in the early stages of treatment. The findings detected by TDI and STE could be missed by conventional echocardiography. We recommend evaluating patients with these newly developed techniques to detect subclinical cardiotoxicity at an early stage and starting appropriate therapy on time.

Intestinal mycobiota composition and changes in children with thalassemia who underwent allogeneic hematopoietic stem cell transplantation.

BACKGROUND: Allogeneic hematopoietic stem cell transplantation (HSCT) alters the diversity of the intestinal bacterial microbiota. This study aimed to evaluate human mycobiota composition pre-HSCT and post-HSCT in children with thalassemia. METHOD: Ten children with thalassemia undergoing allogeneic HSCT were enrolled. The stool samples were collected before the transplantation regimen, before the transplant day, and +15, +30 days, and three months after transplantation. Stool samples were also collected from the donor and the patient's caregivers. Gut mycobiota composition was evaluated with metagenomic analysis. RESULTS: Pretransplant mycobiota of children with thalassemia (the predominant genus was Saccharomyces, 64.1%) has been shown to approximate the diverse mycobiota compositions of healthy adult donors but becomes altered (lower diversity) following transplant procedures. Three months after HSCT, phyla Ascomycota and Basidiomycota were 83.4% and 15.6%, respectively. The predominant species were Saccaharomyces_uc and Saccharomyces cerevisiae (phylum Ascomycota); we also observed Malassezia restricta and Malassezia globosa (phylum Basidiomycota) (∼13%). On day 90 after HSCT, we observed 65.3% M. restricta and 18.4% M. globosa predominance at the species level in a four-year-old boy with acute graft-versus-host disease (GVHD) (skin and gut involvement) 19 days after transplantation included. CONCLUSION: The mycobiota composition of children with thalassemia altered after HSCT. We observed Malassezia predominance in a child with GVHD. Further studies in children with GVHD will identify this situation.