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.

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.

Successful Treatment of Central Nervous System Involvement in Posttransplant EBV-related Lymphoproliferative Disease With Intrathecal Rituximab Therapy.

The posttransplant lymphoproliferative disease is a severe cause of morbidity and mortality following allogeneic hematopoietic stem cell transplantation. Central Nervous System involvement in EBV-related PTLD is rare, and there is no standard treatment recommendation. We present our patient and discuss other previously reported cases of EBV-associated PTLD with CNS involvement.

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.

Hepatitis-Associated Aplastic Anemia: Etiology, Clinical Characteristics and Outcome.

Hepatitis-associated aplastic anemia (HAA) is a form of acquired aplastic anemia (AA) in which bone marrow failure develops after an acute attack of hepatitis. Bone marrow failure leading to AA is generally severe in cases of HAA and fatal if left untreated. This retrospective multicenter study investigated clinical and laboratory characteristics, possible causes, treatment, and outcome of HAA in children. Twenty patients from 8 centers were included in the study. Aspartate aminotransferase and alanine aminotransferase were <3 to 5×upper limit of normal (ULN) in 2 patients, <5 to 10×ULN in 2 patients, and >10×ULN in 16 patients. Acute liver failure developed in 5 (29%) patients. Pancytopenia was simultaneously present in 6 of 20 (30%) patients. Eleven of the 20 patients (55%) were alive, in remission and transfusion free. Those who were alive either had undergone hematopoietic stem cell transplantation and/or immunosuppressive treatment, except 1 patient who had received no treatment. Patients with the diagnosis of acute hepatitis should be evaluated and followed up carefully for presence of cytopenia, so that definitive treatment of AA can be initiated in a timely and appropriate manner when needed.

Central Nervous System Fungal Infections in Children With Leukemia and Undergoing Hematopoietic Stem Cell Transplantation: A Retrospective Multicenter Study.

BACKGROUND: Central nervous system fungal infections (CNSFI) are seen in patients with hematologic malignancies and have high morbidity and mortality. Because of their rarity, there is limited data on CNSFI in children with no established treatment protocols or guidelines. MATERIALS AND METHODS: In this multicenter retrospective study, 51 pediatric patients with leukemia, 6 of whom had undergone bone marrow transplantation, with proven or probable CNSFI were evaluated. Fungal infections were defined as proven or probable based on European Organisation for Research and Treatment of Cancer criteria. Proven CNSFI was diagnosed by appropriate central nervous system (CNS) imaging or tissue sample findings in combination with positive microbiological results of cerebrospinal fluid. A positive culture, microscopic evidence of hyphae, a positive result of the galactomannan assays are defined as positive microbiological evidence. Probable CNSFI was defined as appropriate CNS imaging findings together with proven or probable invasive fungal infections at another focus without CNS when there is no other explanatory condition. Data was collected by using the questionnaire form (Supplemental Digital Content 1, http://links.lww.com/JPHO/A541 ). RESULTS: Seventeen patients had proven, 34 patients had probable CNSFI. Headaches and seizures were the most common clinical findings. The median time between the onset of fever and diagnosis was 5 days. The most common fungal agent identified was Aspergillus . Sixteen patients received single-agent, 35 received combination antifungal therapy. Surgery was performed in 23 patients. Twenty-two patients (43%) died, 29 of the CNSFI episodes recovered with a 20% neurological sequelae. CONCLUSION: CNSFIs should be considered in the differential diagnosis in patients with leukemia and refractory/recurrent fever, headache, neurologicalocular symptoms, and a radiologic-serological evaluation should be performed immediately. Early diagnosis and prompt management, both medical and surgical, are essential for improving clinical outcomes.

Posterior Reversible Encephalopathy Syndrome in Childhood Hematological/Oncological Diseases: Multicenter Results.

The aim of the study was to analyze the characteristics of posterior reversible encephalopathy syndrome (PRES) cases treated at 10 different institutions in our country. Fifty-eight patients diagnosed with PRES were included in this study. The data of PRES cases from 10 departments of pediatric hematology/oncology were analyzed. The mean age of the patients at the time of diagnosis of PRES was 8.95±3.66 years. Most patients (80.4%) had a primary diagnosis of acute leukemia. Patients received chemotherapy (71.4%) and/or used steroids within 14 days before the diagnosis of PRES (85.7%). Hypertension was found in 83.9% of the patients. Twenty-six patients had infections and 22 of them had febrile neutropenia. The most common electrolyte disorders were hypocalcemia, hypomagnesemia, and hypopotassemia. Six patients had tumor lysis syndrome and 4 had inappropriate antidiuretic hormone syndrome. Magnetic resonance imaging was used for diagnosis in all patients. The most commonly involved regions by magnetic resonance imaging were occipital (58%), parietal (51%), and frontal lobes (45%), respectively. Twenty-five patients required intensive care and 7 patients were intubated. In conclusion, PRES may develop during the follow-up and treatment of hematological diseases. In addition to steroid and intense combined chemotherapies, immunosuppressive agents and hypertension are also factors that may be responsible for PRES.

[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.

Cytokine Profile, Apoptosis, Glucocorticoid Receptor, and P-glycoprotein Expression Before and After Megadose Methylprednisolone Treatment in Children With Acute Immune Thrombocytopenia.

OBJECTIVE: Immune thrombocytopenia (ITP) is an autoimmune disease, and it has become evident that T lymphocytes play an important role in the pathogenesis of ITP. We investigated the role of T helper (Th) intracellular IL-2, IL-4, IL-6, IFN-γ, and T lymphocyte apoptosis in the pathogenesis of acute ITP and the effect of glucocorticoid treatment on cytokine profile. We investigated also P-glycoprotein (P-gp) and glucocorticoid receptor (GCR) expression as a possible mechanism for glucocorticoid resistance. MATERIAL AND METHODS: The study includes 20 children with acute ITP having a platelet count <20,000/mm and 20 healthy children as a control group. Patients with acute ITP were treated with megadose methylprednisolone (MDMP) (MDMP in the dose of 30 mg/kg/d between day 1 and 3 and 20 mg/kg/d between day 4 and 7). Th intracellular IL2, IL-4, IL-6, and IFN-γ percentages, T-cell P-gp expression, T-cell and monocyte GCR expression, and T-cell apoptosis were evaluated before and after treatment in acute ITP patients and in the control group. RESULTS: Acute ITP patients had significantly higher Th IL-2, IL-4, IL-6, and IFN-γ percentages compared with the control group (P<0.05). Th IL-2 and IFN-γ percentages were significantly lowered with MDMP treatment (P<0.05). IFN-γ/IL-4 ratio was also lowered with the MDMP treatment (P<0.05). T-lymphocyte P-gp expression and T lymphocyte and monocyte GCR expression were all similar between acute ITP pretreatment and control groups (P>0.05). T-lymphocyte P-gp expression was higher in the posttreatment group than in the pretreatment group (P<0.05). Both T lymphocyte and monocyte GCR expression percentages were not different in the pretreatment and posttreatment groups (P>0.05). Early apoptosis in T lymphocytes was significantly lower in the pretreatment acute ITP group than in the control group (P<0.05). Necrotic apoptosis in T lymphocytes was significantly increased with MDMP treatment (P<0.05). CONCLUSIONS: Th1 and Th2 cytokine profile is observed in acute ITP pathogenesis, and MDMP treatment causes Th1 to Th2 cytokine profile shift and induction of T-lymphocyte apoptosis. There is a need to have a greater number of resistant cases in order to better evaluate the P-gp and GCR expression in glucocorticoid resistance in acute ITP.

Hepatosplenic Fungal Infections in Children With Leukemia-Risk Factors and Outcome: A Multicentric Study.

BACKGROUND: Invasive fungal infections, including hepatosplenic fungal infections (HSFI), cause significant morbidity and mortality in children with leukemia. There are not enough data to support for the best approach to diagnosis of HSFI in children, nor for the best treatment. PROCEDURE: In this multicentric study, we assessed the demographic data, clinical and radiologic features, treatment, and outcome of 40 children with leukemia and HSFI from 12 centers. RESULTS: All cases were radiologically diagnosed with abdominal ultrasound, which was performed at a median of 7 days, of the febrile neutropenic episode. Mucor was identified by histopathology in 1, and Candida was identified in blood cultures in 8 patients. Twenty-two had fungal infection in additional sites, mostly lungs. Nine patients died. Four received a single agent, and 36 a combination of antifungals. CONCLUSIONS: Early diagnosis of HSFI is challenging because signs and symptoms are usually nonspecific. In neutropenic children, persistent fever, back pain extending to the shoulder, widespread muscle pain, and increased serum galactomannan levels should alert clinicians. Abdominal imaging, particularly an abdominal ultrasound, which is easy to perform and available even in most resource-limited countries, should be recommended in children with prolonged neutropenic fever, even in the absence of localizing signs and symptoms.

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.

Aceruloplasminemia in a Turkish adolescent with a novel mutation of ceruloplasmin gene: the first diagnosed case from Turkey.

Aceruloplasminemia is a rare autosomal recessive disease that affects the iron metabolism of the body. When there is a lack of ceruloplasmin ferroxidase activity, iron accumulates, especially in the brain, pancreas, liver, and retina. The first symptom is generally a persistent hypochromic microcytic anemia with a mild high-serum ferritin level. The affected patients are usually recognized at later ages, when the neurological symptoms appear. The neurological outcome has an adverse effect on the prognosis, which may result in fatality. Therefore, early diagnosis and intervention may prevent a devastating neurological damage. Here, we report a case of aceruloplasminemia in a teenage girl with hypochromic microcytic anemia.

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.

Incidence and Management of Thromboembolism in Patients with Acute Leukemia.

Thromboembolic events (TE) in childhood are relatively rare but, serious complications of acute leukemia. The aim was to define the incidence and risk factors of thrombosis in children with leukemias. The electronic files of pediatric denovo/relapsed acute leukemia patients aged below 18 years, treated between 2011 and 2021 were retrospectively evaluated for thrombotic attacks. Thirty out of 469 patients developed 35 thrombotic events. The median age at the time of the TE was 11.8 (2-17.6) years, and the median time from diagnosis to TE was 9 (0-58) months. The frequency of TE was found at 7.4% (n = 35/469). When catheter related (n = 13) events, superficial venous events (n = 10), and arterial central nervous system thrombosis (n = 1) were excluded, the frequency of TE was decreased to 2.3% (n = 11/469). Children older than 10 years old (13.8%; n = 21/152) had significantly higher thromboembolic events than the others (4.4%; n = 14/317) (p = 0.03). The majority of attacks were symptomatic 66% (n = 23/35). The most common complaints were local pain, swelling, and redness 52% (n = 12/23). The majority of attacks in patients with relapsed (75%; 6/8) and newly diagnosed acute lymphoblastic leukemia (40%; 10/25%) developed during the induction phase. Thrombosis recurred in 13.3% (n = 4/30) of cases more than once. Thrombotic attacks were successfully treated with low molecular weight heparin 60% (n = 21/35), and recombinant tissue plasminogen activator 17% (n = 6/35). None of the children were lost due to thrombosis. Thrombosis is an important complication during acute leukemia treatment. Successful results are obtained with early diagnosis and treatment attempts by creating awareness.

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