Pyruvate kinase deficiency in 29 Turkish patients with two novel intronic variants.

Pyruvate kinase (PK) is a key enzyme of anaerobic glycolysis. The genetic heterogeneity of PK deficiency (PKD) is high, and over 400 unique variants have been identified. Twenty-nine patients who had been diagnosed as PKD genetically in seven distinct paediatric haematology departments were evaluated. Fifteen of 23 patients (65.2%) had low PK levels. The PK:hexokinase ratio had 100% sensitivity for PKD diagnosis, superior to PK enzyme assay. Two novel intronic variants (c.695-1G>A and c.694+43C>T) have been described. PKD should be suspected in patients with chronic non-spherocytic haemolytic anaemia, even if enzyme levels are falsely normal. Total PKLR gene sequencing is necessary for the characterization of patients with PKD and for genetic counselling.

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.

Prognosis of Second Primary Malignancies in Pediatric Acute Lymphoblastic Leukemia Survivors: A Multicenter Study by the Turkish Pediatric Hematology Society.

The improved survival rates of childhood cancers raise the long-term risk of second primary malignancy (SPM) in childhood and adolescent cancer survivors. The intensity of the treatment protocol used, the use of some groups of chemotherapeutics, and radiotherapy were found to be risk factors for the development of second primary malignancies (SPMs). Forty-one patients who developed acute myelocytic leukemia or any solid organ cancer within 25 years of follow-up, after completion of pediatric acute lymphoblastic leukemia (ALL) treatment, were included in the study. The mean duration of initial ALL diagnosis to SPM was 9.3 ± 6.1 years. The 3 most common SPMs were acute myelocytic leukemia, glial tumors, and thyroid cancer. Thirteen (81%) of 16 patients exposed to cranial irradiation had cancer related to the radiation field. In total 13/41 (32%) patients died, and the 5-year overall survival rate was 70 ± 8%. Patients older than 5 years old at ALL diagnosis had significantly worse overall survival than cases younger than 5 years old. In conclusion, children and adolescents who survive ALL have an increased risk of developing SPM compared with healthy populations, and physicians following these patients should screen for SPMs at regular intervals.

Prevalence of anemia at diagnosis of pediatric chronic myeloid leukemia and prognostic impact on the disease course.

The clinical presentation of chronic myeloid leukemia (CML) at diagnosis differs in children compared to adults. At younger age, anemia appears to be frequent at diagnosis, but its prevalence and its impact on prognosis are not well known. In the International Registry of Childhood CML, we selected children and adolescents in chronic phase at diagnosis of CML and treated upfront with imatinib. We examined their hemoglobin level at diagnosis according to the WHO grades to assess the prevalence of anemia and its impact on response to tyrosine kinase inhibitors (TKIs). Data on 430 patients were included. Anemia at diagnosis was observed in 350 patients (81%), with a mean hemoglobin level of 96.4 g/l (SD 23.6). Among them, 182 patients (52%) presented with moderate anemia and 110 (31%) with severe anemia while 58 (17%) had mild anemia. Compared with mild and no anemia, moderate and severe forms were significantly associated with younger age at diagnosis, asthenia, splenomegaly, and increased leukocyte and basophil counts. Delays in achieving major and deep molecular responses were significantly increased for patients with moderate and severe anemia, and also failure of imatinib treatment was more frequent in these two sub-cohorts. However, hemoglobin level was not significantly associated with survival. Anemia at diagnosis of pediatric CML was frequent and may be considered as a prognostic factor.

The Evaluation of Central Venous Catheter-related Complications in Pediatric Acute Leukemia Patients: Single Center Experience.

Central venous catheters (CVCs) are important for maintenance of childhood leukemia treatment but CVCs may develop complications. The aim of this study was to retrospectively evaluate the CVC-related complication rate, complication types, and outcome in children with acute leukemia. Complications developing in 310 CVCs (ports n=250, Hickman catheters n=60) inserted in 262 patients were evaluated. A total of 225,296 catheter days were screened. Median (range) CVC in-dwelling time was 661.5 (1 to 2636) days. In total, 157 complications developed of which 91 (58%) were infectious complications, 35 (22.3%) were vascular, 19 (12.1%) were surgical, and 12 (7.6%) were mechanical. Hickman catheters had a higher complication rate and were more prone to mechanical complications ( P <0.01) but there was no difference for other complications. A lower absolute neutrophil count at insertion was observed in children with infectious complications ( P <0.01). Seventy-eight of 136 catheters (57.3%) had to be removed prematurely. The overall complication rate was 0.65 per 1000 catheter days. In multivariate analysis, relapse leukemia, Hickman catheter and low absolute neutrophil count increased complication risk by 4.00, 1.97, and 1.92 times, respectively. Five (1.9%) deaths occurred because of catheter complications. Safe use of CVCs can be improved by early detection of complications and an experienced catheter care team.

Assessment of Minimal Residual Disease in Childhood Acute Lymphoblastic Leukemia: A Multicenter Study From Turkey.

Assestment of minimal residual disease (MRD) in childhood acute lymphoblastic leukemia (ALL) is of utmost importance both for risk classification and tailoring of the therapy. The data of pediatric ALL patients that received treatment with Berlin-Frankfurt-Münster (BFM) protocols were retrospectively collected from 5 university hospitals in Turkey. Of the 1388 patients enrolled in the study 390 were treated according to MRD-based protocols. MRD assestment was with real time quantitative polymerase chain reaction (qPCR) in 283 patients and with multiparametric flow cytometry (MFC)-MRD in 107 patients. MRD monitoring had upstaged a total of 8 patients (2%) from intermediate risk group to high-risk group. Univariate analysis revealed age 10 years or above, prednisone poor response, PCR-MRD ≥10-3 on day 33 and on day 78 as poor prognostic factors affecting event-free survival (EFS). Detection of >10% blasts on day 15 with MFC (MFC-high-risk group) was not shown to affect EFS and/or overall survival (log-rank P=0.339). Multiple logistic regression analysis revealed PCR-MRD ≥10-3 on day 78 as the only poor prognostic factor affecting EFS (odds ratio: 8.03; 95% confidence interval: 2.5-25; P=0.000). It is very important to establish the infrastructure and ensure necessary standardization for both MRD methods for optimal management of children with ALL.

Identification and in silico characterization of a novel PKLR genotype in a Turkish newborn.

Pyruvate kinase deficiency (PKD) is the most common glycolytic defect leading to chronic nonspherocytic hemolytic anemia (CNSHA). Clinical manifestations of PKD reflect the symptoms and complications of the chronic hemolysis, including anemia, jaundice, bilirubin gallstones due to hyperbilirubinemia, splenomegaly and iron overload. In this study, we report the finding of a 5-months-old Turkish male newborn with moderate CNSHA and PKD. Mutation screening of Pyruvate Kinase Liver/Red (PKLR) gene revealed that the patient carried the known pathogenic variant (PV) c.1456C > T (p.Arg486Trp) and an unreported variant c.1067T > G (p.Met356Arg). Computational variant analysis (CVA) highlighted the deleterious structural effects on the mutant PK enzyme, suggesting its pathogenic role. In this patient, the molecular evaluation of PKD, that allowed the identification of the novel PKLR genotype, coupled with CVA led to the definitive and correct diagnosis of CNSHA.

[Evaluation of Micafungin Use in Children]. / Çocuklarda Mikafungin Kullaniminin Degerlendirilmesi.

Micafungin is recommended especially in patients with liver and kidney failure and in the presence of other side effects due to antifungals apart from its known priority indications such as invasive candidiasis. The aim of this study was to evaluate the children who have received micafungin treatment. In the study, 125 children who were hospitalized in the pediatric wards and intensive care units of our hospital and had used micafungin between November 2016 and January 2019 were analyzed retrospectively. Clinical data, micafungin indication, blood values on the first and fourth days of the treatment, side effects of the drug and efficacy were evaluated. Sixty percent (75/125) of the patients were male and the mean age of all the patients were 58 ± 67 (0-215, 30) months. Approximately half of the cases (48%) had malignancy and 13% of them were premature. Sixty-two percent (n= 37) of the malignencies were hematological (27 acute lymphocytic leukemia, nine acute myeloid leukemia, one myelodysplastic syndrome) and 38% (n= 23) were oncological (six neuroblastoma, four Hodgkin lymphoma, two Non-Hodgkin's lymphoma, five sarcomas, one hepatoblastoma, five others) malignencies. The major cause of hospitalization was sepsis (53%). The patients had several risk factors like immunosuppressive therapy (n= 68, 54%), neutropenia (n= 61, 49%), central venous catheter (n= 102, 82%), nasogastric tube (n= 63, 50%), endotracheal intubation tube (n= 49, 39%), urinary catheter (n= 14, 11%) and total parenteral nutrition (n= 81, 65%). Thirteen percent (n= 16) of the cases were post-operative patients. Candida species were cultivated in 97 clinical specimens (blood, endotracheal aspirate, sputum, urine, etc.) among 23 (18%) of the patients. Thirteen (10%) of the patients had candidemia and 62% of them were non-albicans strains. In all candidemias, strains were echinocandin susceptible, and blood cultures were negative within four days. When all the patients (n= 125) were evaluated, a significant decrease in C-reactive protein, an increase in sodium, and a decrease in alanine aminotransferase were observed on the fourth day of micafungin treatment (p<0.05). A total of 39 (31%) patients underwent various antifungal treatments for median seven (1-60) days prior to micafungin treatment. Fourteen (36%) of these 39 patients, had elevated liver function tests (LFT), 10 (26%) of them had hypokalemia, and five (13%) of them had elevated renal function tests. Ten (26%) patients had antifungal-induced hypokalemia previously; and potassium levels were normalized after micafungin treatment (p= 0.0001). The patients for which micafungin treatment was chosen due to elevated liver function tests (n= 47, 38%), whether the antifungalinduced or not; alanine aminotransferase and aspartate aminotransferase levels were decreased after micafungin treatment (p= 0.0001 and p= 0.0001, respectively). Nineteen (15%) of the patients have died within the first 30 days of micafungin treatment and one of them had candidemia. No micafungin treatment related significant side effects were observed in any of the patients. Our study showed that micafungin could be a safe and effective option in pediatric cases including newborns with high liver and kidney function tests.

Generic formulations of imatinib for treatment of Philadelphia chromosome-positive leukemia in pediatric patients.

Since the patent for imatinib has expired, the role of generic imatinib (GI) in the management of Philadelphia chromosome-positive (Ph+) leukemia in pediatric patients has had ongoing discussion. Some studies in adults demonstrated that equivalent doses of GI and branded imatinib (BI) result in comparable plasma concentrations and clinical efficacy. However, other studies found that GI users are more likely to stop imatinib, with intolerance and decreased persistence as the main causes. Economic factors also heavily influence GI selection. This article aims to review the present knowledge to support further discussion on the role of GI in the management of pediatric Ph+ leukemia.

Additional cytogenetic abnormalities and variant t(9;22) at the diagnosis of childhood chronic myeloid leukemia: The experience of the International Registry for Chronic Myeloid Leukemia in Children and Adolescents.

BACKGROUND: In the adult population with newly diagnosed chronic myeloid leukemia (CML), variant translocations are usually not considered to be impairing the prognosis, whereas some additional cytogenetic abnormalities (ACAs) are associated with a negative impact on survival. Because of the rarity of CML in the pediatric population, such abnormalities have not been investigated in a large group of children with CML. METHODS: The prognostic relevance of variant t(9;22) and ACAs at diagnosis was assessed in 301 children with CML in the chronic phase who were enrolled in the International Registry for Chronic Myeloid Leukemia in Children and Adolescents. RESULTS: Overall, 19 children (6.3%) presented with additional cytogenetic findings at diagnosis: 5 children (1.7%) had a variant t(9;22) translocation, 13 children (4.3%) had ACAs, and 1 had both. At 3 years, for children with a classic translocation, children with ACAs, and children with a variant t(9;22) translocation who were treated with imatinib as frontline therapy, the probability of progression-free survival (PFS) was 95% (95% confidence interval [CI], 91%-97%), 100%, and 75% (95% CI, 13%-96%), respectively, and the probability of overall survival (OS) was 98% (95% CI, 95%-100%), 100% (95% CI, 43%-98%), and 75% (95% CI, 13%-96%), respectively. No statistical difference was observed between the patients with classic cytogenetic findings and those with additional chromosomal abnormalities in terms of PFS and OS. CONCLUSIONS: In contrast to adults with CML, additional chromosomal abnormalities observed at diagnosis do not seem to have a significant prognostic impact. Cancer 2017;123:3609-16. © 2017 American Cancer Society.

Prognostic discrimination based on the EUTOS long-term survival score within the International Registry for Chronic Myeloid Leukemia in children and adolescents.

The EUTOS Long-Term Survival score was tested in 350 children with chronic myeloid leukemia in first chronic phase treated with imatinib and registered in the International Registry for Childhood Chronic Myeloid Leukemia. With a median follow up of 3 years (range, 1 month to 6 years) progression and/or death (whichever came first) occurred in 23 patients. For the entire cohort of patients the 5-year progression-free survival rate was 92% (95% CI: 87%-94%) and the 5-year survival accounting for chronic myeloid leukemia deaths was 97% (95% CI: 94%-99%). Of the 309 patients allocated to low (n=199), intermediate (n=68) and high (n=42) risk groups by the EUTOS Long-Term Survival score, events (progression and/or death) occurred in 6.0%, 8.8% and 26.2%, respectively. Estimates of the 5-year progression-free survival rates according to these three risk groups were 96% (95% CI: 92%-98%), 88% (95% CI: 76%-95%) and 67% (95% CI: 48%-81%), respectively. Differences in progression-free survival according to these risk groups were highly significant (P<0.0001, overall). The EUTOS Long-Term Survival score showed better differentiation of progression-free survival than the Sokal (<45 years), Euro and EUTOS scores in children and adolescents with chronic myeloid leukemia and should be considered in therapeutic algorithms. (Trial registered at: www.clinicaltrials.gov NCT01281735).

The long-term results of childhood acute lymphoblastic leukemia at two centers from Turkey: 15 years of experience with the ALL-BFM 95 protocol.

Dramatic progress in the treatment of childhood acute lymphoblastic leukemia (ALL) has been achieved during the last two decades in Western countries, where the 5-year event-free survival (EFS) rate has risen from 30 to 85 %. However, similarly high cure rates have not always been achieved in all centers in developing countries due to limited sources. We evaluated the treatment results of the ALL-Berlin-Frankfurt-Münster (BFM) 95 protocol as used between 1995 and 2009 in the pediatric hematology departments of two university hospitals. A retrospective analysis of 343 children newly diagnosed with ALL (M/F 200/143, median age 6.8 years) was performed. The overall survival (OS) and EFS according to age, initial leukocyte count, immunophenotype, chemotherapy responses (on days 8, 15, and 33), and risk groups were analyzed by Kaplan-Meier survival analysis. Median follow-up time was 6.4 years. Complete remission was achieved in 97 % of children. Five-year EFS and OS were found to be 78.4 and 79.9 %, respectively. Children younger than 6 years old had significantly better EFS and OS (83.7 and 85.2 %) than children aged ≥6 years (71.4 and 72.8 %). Adolescents achieved 63 % EFS and 65 % OS. Patients who had initial leukocyte counts of <20 × 10(9)/L had better EFS and OS (82.2 and 84.6 %) than children with higher initial leukocyte counts (72.6 and 72.6 %). EFS for B-cell precursor and T-cell ALL was 81.5 and 66.7 %, respectively. Children with a good response to prednisolone on day 8 (87 %) achieved significantly better EFS and OS (81.2 and 81.9 % vs. 55.3 and 60.5 %). Children whose bone marrow on day 15 was in complete remission had higher EFS and OS (83.7 and 86.6.1 % vs. 56.4 and 61.5 %). Children in the standard-risk and medium-risk groups obtained statistically significantly higher EFS (95.5 and 82.7 %) and OS (97.7 and 82.3 %) compared to the high-risk group (EFS 56.3 %, OS 63.4 %). The relapse rate was 14.8 %. The median relapse time from diagnosis was 23.2 months. Death occurred in 69 of 343 patients (20.1 %). The major causes of death were infection and relapse. None of the patients died of drug-related toxicity. The ALL-BFM 95 protocol was applied successfully in these two centers. In developing countries in which minimal residual disease cannot be monitored, this protocol can still be used with high survival rates.

Childhood Immune Thrombocytopenia: Long-term Follow-up Data Evaluated by the Criteria of the International Working Group on Immune Thrombocytopenic Purpura.

OBJECTIVE: Immune thrombocytopenia (ITP) is a common bleeding disorder in childhood, characterized by isolated thrombocytopenia. The International Working Group (IWG) on ITP recently published a consensus report about the standardization of terminology, definitions, and outcome criteria in ITP to overcome the difficulties in these areas. MATERIALS AND METHODS: The records of patients were retrospectively collected from January 2000 to December 2009 to evaluate the data of children with ITP by using the new definitions of the IWG. RESULTS: The data of 201 children were included in the study. The median follow-up period was 22 months (range: 12-131 months). The median age and platelet count at presentation were 69 months (range: 7-208 months) and 19x10(9)/L (range: 1x10(9)/L to 93x10(9)/L), respectively. We found 2 risk factors for chronic course of ITP: female sex (OR=2.55, CI=1.31-4.95) and age being more than 10 years (OR=3.0, CI=1.5-5.98). Life-threatening bleeding occurred in 5% (n=9) of the patients. Splenectomy was required in 7 (3%) cases. When we excluded 2 splenectomized cases, complete remission at 1 year was achieved in 70% (n=139/199). The disease was resolved in 9 more children between 12 and 90 months. CONCLUSION: Female sex and age above 10 years old significantly influenced chronicity. Therefore, long-term follow-up is necessary in these children.

Catheter-associated bloodstream infections in pediatric hematology-oncology patients.

Catheter-associated bloodstream infections (CABSIs) are common complications encountered with cancer treatment. The aims of this study were to analyze the factors associated with recurrent infection and catheter removal in pediatric hematology-oncology patients. All cases of CABSIs in patients attending the Department of Pediatric Hematology-Oncology between January 2008 and December 2010 were reviewed. A total of 44 episodes of CABSIs, including multiple episodes involving the same catheter, were identified in 31 children with cancer. The overall CABSIs rate was 7.4 infections per 1000 central venous catheter (CVC) days. The most frequent organism isolated was coagulase-negative Staphylococcus (CONS). The CVC was removed in nine (20.4%) episodes. We found that hypotension, persistent bacteremia, Candida infection, exit-side infection, neutropenia, and prolonged duration of neutropenia were the factors for catheter removal. There were 23 (52.2%) episodes of recurrence or reinfection. Mortality rate was found to be 9.6% in children with CABSIs. In this study, we found that CABSIs rate was 7.4 infections per 1000 catheter-days. CABSIs rates in our hematology-oncology patients are comparable to prior reports. Because CONS is the most common isolated microorganism in CABSIs, vancomycin can be considered part of the initial empirical regimen.

Cerebellar granulocytic sarcoma: a case report.

Granulocytic sarcoma is a rare tumor composed of immature granulocytic cells that is usually associated with acute myelogenous leukemia. Intraparenchymal cranial localization without skull, meningeal, or bone marrow invasion is extremely rare. The mechanisms of intraparenchymal cranial localization of GS remains unknown, as only 10 cases with cerebellar granulocytic sarcoma have been previously reported. Herein, we report a four year old boy with cerebellar localization of granulocytic sarcoma.

Invasive Fungal Infections in Children with Leukemia: Clinical Features and Prognosis

Objective: The incidence of invasive fungal infections (IFIs) has increased due to intensive chemotherapy in childhood leukemia. The aim of this study was to evaluate the incidence, risk factors, causative pathogens, and impact on survival of IFIs among pediatric leukemia patients. Materials and Methods: The hospital records of 307 children with acute lymphoblastic leukemia (ALL, n=238), acute myeloid leukemia (AML, n=51), and relapsed leukemia (n=18) between January 2010 and December 2015 were retrospectively evaluated. Results: A total of 1213 febrile neutropenia episodes were recorded and 127 (10.4%) of them were related to an IFI. Of 307 children, 121 (39.4%) developed IFIs. The mean age was significantly older in the IFI group compared to children without IFIs (p<0.001). IFIs were defined as possible, probable, and proven in 73.2%, 11.9%, and 14.9% of the attacks, respectively. Invasive aspergillosis (81.9%) was the most frequent infection, followed by invasive candidiasis (13.4%) and rare fungal diseases (4.8%). The majority of IFI attacks in both ALL and AML occurred during the induction phase. In total, the death rate was 24% and the IFI-related mortality rate was 18%. The mortality rate among children with IFIs was found to be significantly higher than that of children without IFIs (p<0.001). Overall and event-free survival rates at 5 years were also found to be significantly lower in the IFI group (p<0.001). Relapse (odds ratio: 8.49) was the most effective risk factor for mortality, followed by developing an IFI episode (odds ratio: 3.2) and AML (odds ratio: 2.33) according to multivariate regression analysis. Conclusion: Our data showed that IFIs were more common in older children. Although proven and probable IFI episodes were more frequently diagnosed in cases of relapse and AML, children with ALL and AML had similar frequencies of experiencing at least one episode Conclusion: Our data showed that IFIs were more common in older children. Although proven and probable IFI episodes were more frequently diagnosed in cases of relapse and AML, children with ALL and AML had similar frequencies of experiencing at least one episode

Hyperuricemia and tumor lysis syndrome in children with non-Hodgkin's lymphoma and acute lymphoblastic leukemia.

OBJECTIVE: This study aimed to examine the incidence, clinical characteristics, and outcome of hyperuricemia and tumor lysis syndrome (TLS) in children with non-Hodgkin's lymphoma (NHL) and acute lymphoblastic leukemia (ALL). METHODS: This retrospective study included data from 327 patients (113 NHL and 214 ALL). RESULTS: Hyperuricemia occurred in 26.5% and 12.6% of the patients with NHL and ALL, respectively. The corresponding figures for TLS were 15.9% and 0.47% (p=0.001). All hyperuricemic NHL patients had advanced disease and renal involvement was present in 53%. All hyperuricemic ALL patients had a leukocyte count >50,000 mm3 at the time of diagnosis. Among the hyperuricemic NHL and ALL patients, 96.6% and 66.6% had LDH ≥500 UI/L, respectively. Treatment consisted of hydration and allopurinol; none of the patients received urate oxidase. Among the patients that developed TLS, 26.3% had laboratory TLS, 42.1% had grade I or II TLS, and 31.6% had grade III or IV TLS. Uric acid levels returned to normal after a mean period of 3.5±2.5 and 3.05±0.8 d in NHL and ALL groups, respectively. In all, 7% of the patients with hyperuricemia required hemodialysis. None of the patients died. CONCLUSION: In this series the factors associated with a high-risk for TLS were renal involvement in NHL and high leucocyte count in ALL. Management with allopurinol and hydration was effective in this group of patients with high tumor burden.

Long-term outcome in children with nutritional vitamin B12 deficiency.

OBJECTIVE: Vitamin B12 deficiency is frequently observed in developing countries. Herein we report the long-term clinical and laboratory outcomes in 45 children presented with various symptoms of vitamin B12 deficiency. METHODS: Symptoms and physical findings, and percentiles for weight, height, and head circumference at presentation were recorded. The educational level of the patients' mothers, vitamin B12 deficiency-related diseases and family income data were collected. Complete blood count, serum vitamin B12, folate, iron, iron binding capacity and ferritin, and plasma homocysteine levels were recorded measured at presentation. The patients were treated with vitamin B12, as follows: 1 mg/d IM for 1 week, followed by 1 mg IM QWK for 2 weeks, and then monthly 1mg injections. Patients were neurologically and hematologically re-evaluated after treatment. The visual evoked potential (VEP) test was used to examine the integrity and function of the visual pathway. Brainstem evoked potential (BAEP) responses were used to analyze auditory function. Neuromotor development was assessed using Denver II Development Screening Test. RESULTS: The mean age of 20 male and 25 female patients was 5.6±5.9 years (range: 1.4 months-17 years). The most common symptoms at presentation were weakness, failure to thrive, and hematologic manifestations (pallor, petechiae, ecchymosis). Abnormal neurologic findings at presentation were observed in 20% of the patients, and were more commonly observed in those <2 years. VEP, BAEP, and Denver II Development tests were performed in 66% of the patients one year after vitamin B12 replacement was started. VEP and BAEP interval prolongation was observed in 37% and 17% of the cases, respectively. Denver II Development Test results showed developmental delay in 20% of the patients tested. CONCLUSION: All the patients achieved full hematologic recovery within 1 month of treatment onset. Neurological symptoms resolved following B12 administration; however, during long-term follow-up ranged from 17% to 37% of the tested patients had persistent VEP; BERA, and Denver II abnormalities. Neurological symptoms resolved following B12 administration; however, during long-term followup 33% of the patients had persistent VEP, BERA, and Denver II abnormalities. As such, clinicians should continue to follow-up such patients even after hematologic and clinical improvement are obtained in order to assess their neurologic status.

Thrombolysis with Systemic Recombinant Tissue Plasminogen Activator in Children: A Multicenter Retrospective Study

Objective: This study aimed to evaluate systemic thrombolysis experiences with recombinant tissue plasminogen activator (rtPA). Materials and Methods: Retrospective data were collected from 13 Turkish pediatric hematology centers. The dose and duration of rtPA treatment, concomitant anticoagulant treatment, complete clot resolution (CCR), partial clot resolution (PCR), and bleeding complications were evaluated. Low-dose (LD) rtPA treatment was defined as 0.01-0.06 mg/kg/h and high-dose (HD) rtPA as 0.1-0.5 mg/kg/h. Results: Between 2005 and 2019, 55 thrombotic episodes of 54 pediatric patients with a median age of 5 years (range: 1 day to 17.75 years) were evaluated. These patients had intracardiac thrombosis (n=16), deep vein thrombosis (DVT) (n=15), non-stroke arterial thrombosis (n=14), pulmonary thromboembolism (PE) (n=6), and stroke (n=4). The duration from thrombus detection to rtPA initiation was a median of 12 h (range: 2-504 h) and it was significantly longer in cases of DVT and PE compared to stroke, non-stroke arterial thrombosis, and intracardiac thrombosis (p=0.024). In 63.6% of the episodes, heparin was initiated before rtPA treatment. LD and HD rtPA were administered in 22 and 33 of the episodes, respectively. Concomitant anticoagulation was used in 90% and 36% of the episodes with LD and HD rtPA, respectively (p=0.0001). Median total duration of LD and HD rtPA infusions was 30 h (range: 2-120 h) and 18 h (2-120 h), respectively (p=0.044). Non-fatal major and minor bleeding rates were 12.5% and 16.7% for LD and 3.2% and 25.8% for HD rtPA, respectively. At the end of the rtPA infusions, CCR and PCR were achieved in 32.7% and 49.0% of the episodes, respectively. The most successful site for thrombolysis was intracardiac thrombosis. HD versus LD rtPA administration was not correlated with CCR/PCR or bleeding (p>0.05). Conclusion: Systemic thrombolytic therapy may save lives and organs effectively if it is used at the right indications and the right times in children with high-risk thrombosis by experienced hematologists with close monitoring of recanalization and bleeding.

Clofarabine-induced capillary leak syndrome in a child with refractory acute lymphoblastic leukemia.

Clofarabine has significant efficiency in children with relapsed or refractory leukemia. In previous pediatric trials, various adverse effects have been described. In this case, we report a child with refractory acute lymphoblastic leukemia who developed fatal capillary leak syndrome during clofarabine therapy.