Efficacy of T cell assays for the diagnosis of primary defects in cytotoxic lymphocyte exocytosis.

Primary hemophagocytic lymphohistiocytosis (HLH) is a life-threatening disorder associated with autosomal recessive variants in genes required for perforin-mediated lymphocyte cytotoxicity. A rapid diagnosis is crucial for successful treatment. Although defective cytotoxic T lymphocyte (CTL) function causes pathogenesis, quantification of natural killer (NK) cell exocytosis triggered by K562 target cells currently represents a standard diagnostic procedure for primary HLH. We have prospectively evaluated different lymphocyte exocytosis assays in 213 patients referred for evaluation for suspected HLH and related hyperinflammatory syndromes. A total of 138 patients received a molecular diagnosis consistent with primary HLH. Compared to routine K562 cell-based assays, assessment of Fc receptor-triggered NK-cell and T cell receptor-triggered CTL exocytosis displayed higher sensitivity and improved specificity for the diagnosis of primary HLH, with these assays combined providing a sensitivity of 100% and specificity of 98.3%. By comparison, NK-cell exocytosis following K562 target cell stimulation displayed a higher inter-individual variability, in part explained by differences in NK-cell differentiation or large functional reductions following shipment. We thus recommend combined analysis of T cell receptor-triggered CTL and Fc receptor-triggered NK-cell exocytosis for the diagnosis of patients with suspected familial HLH or atypical manifestations of congenital defects in lymphocyte exocytosis.

Nutritional Status of Pediatric Patients With Acute Lymphoblastic Leukemia Under Chemotherapy: A Pilot Longitudinal Study.

BACKGROUND: The study investigates the nutritional status in children with acute lymphoblastic leukemia (ALL) during chemotherapy treatment because nourishment is substantial, as much as chemotherapy in children with malignant diseases. MATERIAL AND METHOD: We enrolled 17 children with ALL (between 1 to 16 year-old, mean age 6.03 ± 4.04 y) from 5 different centers in Istanbul between September 2013 and May 2014. Anthropometric data, prealbumin, B12, and folate levels were assessed, at diagnosis, after the induction phase of chemotherapy, and before maintenance phases of chemotherapy in a longitudinal and prospective study. RESULTS: Patients remarkably lost weight at the end of the induction phase ( P =0.064) and regained this loss before maintenance chemotherapy ( P =0.001). At the end of induction chemotherapy serum prealbumin level ( P =0.002), weight for height ratios ( P =0.016), weight for age ratios ( P =0.019) significantly decreased. From the end of the induction phase to the beginning of maintenance chemotherapy, weight ( P =0.001) and weight for age ( P =0.017) significantly, and weight for height were remarkably elevated ( P =0.076). At the end of the induction phase, serum prealbumin levels were significantly lower ( P =0.048) and below laboratory reference values ( P =0.009) in children younger than 60 months compared with those older. Serum folate levels increased from the end of the induction phase to the beginning of the maintenance phase ( P =0.025). Serum vitamin B12 levels did not alter significantly. CONCLUSION: There is malnutrition risk at the end of the induction phase of the ALL-BFM chemotherapy regimen; therefore, clinicians should follow up on nutrition closely, especially in under 5-year-old patients. However, before the beginning of the maintenance phase, children start to gain weight, and obesity risk occurs. Thus , further studies are needed to evaluate nutritional status during childhood ALL chemotherapy.

ILC3 deficiency and generalized ILC abnormalities in DOCK8-deficient patients.

BACKGROUND: Dedicator of cytokinesis 8 (DOCK8) deficiency is the main cause of the autosomal recessive hyper-IgE syndrome (HIES). We previously reported the selective loss of group 3 innate lymphoid cell (ILC) number and function in a Dock8-deficient mouse model. In this study, we sought to test whether DOCK8 is required for the function and maintenance of ILC subsets in humans. METHODS: Peripheral blood ILC1-3 subsets of 16 DOCK8-deficient patients recruited at the pretransplant stage, and seven patients with autosomal dominant (AD) HIES due to STAT3 mutations, were compared with those of healthy controls or post-transplant DOCK8-deficient patients (n = 12) by flow cytometry and real-time qPCR. Sorted total ILCs from DOCK8- or STAT3-mutant patients and healthy controls were assayed for survival, apoptosis, proliferation, and activation by IL-7, IL-23, and IL-12 by cell culture, flow cytometry, and phospho-flow assays. RESULTS: DOCK8-deficient but not STAT3-mutant patients exhibited a profound depletion of ILC3s, and to a lesser extent ILC2s, in their peripheral blood. DOCK8-deficient ILC1-3 subsets had defective proliferation, expressed lower levels of IL-7R, responded less to IL-7, IL-12, or IL-23 cytokines, and were more prone to apoptosis compared with those of healthy controls. CONCLUSION: DOCK8 regulates human ILC3 expansion and survival, and more globally ILC cytokine signaling and proliferation. DOCK8 deficiency leads to loss of ILC3 from peripheral blood. ILC3 deficiency may contribute to the susceptibility of DOCK8-deficient patients to infections.

The Role of Anti-Neutrophil Antibodies in the Etiologic Classification of Childhood Neutropenia: A Cross-Sectional Study in a Tertiary Center.

Infections, drugs, malignancies, immunodeficiency, and autoimmunity may cause neutropenia. In primary autoimmune neutropenia, anti-neutrophil antibodies (ANeuA) bind to membrane antigens of neutrophils, which give rise to peripheral destruction of neutrophils. However, it is not always easy to detect these antibodies. This study aims to investigate the etiology of neutropenia, and at the same time to evaluate the immune mechanisms by ANeuA testing using granulocyte indirect immunofluorescence test. In our study, 310 neutropenic patients who were between 3 months and 18 years of age were evaluated. ANeuA screening tests were performed in 108 neutropenic patients (group 1), and these patients were divided into 2 subgroups as persistent neutropenia (group 1P, n=12) and recovered neutropenia (group 1R, n=96). Besides, a control group in the same age range was formed, consisting of 39 non-neutropenic children (group 2). ANeuA serum levels were also checked in these groups, and no statistically significant difference could be found between groups 1 and 2, or between groups 1P and 1R, regarding ANeuA levels. As a conclusion, our study was the first comprehensive research in Turkey investigating the large-scale etiology of neutropenia. Moreover, while ANeuA screening tests did not provide sufficient insight for immune neutropenia, we argue that it is not necessary for routine use and that further research in the etiology of neutropenia is required.

Upregulation of T-Cell-Specific Transcription Factor Expression in Pediatric T-Cell Acute Lymphoblastic Leukemia (T-ALL).

OBJECTIVE: T-cell acute lymphoblastic leukemia (T-ALL) is associated with recurrent chromosomal aberrations andabnormal ectopic gene expression during T-cell development. In order to gain insight into the pathogenesis of T-ALLthis study aimed to measure the level of expression of 7 T-cell oncogenes (LMO2, LYL1, TAL1, TLX1, TLX3, BMI1, andCALM-AF10) in pediatric T-ALL patients Material and Methods: LMO2, LYL1, TLX1, TLX3, BMI1, TAL1, and CALM-AF10 expression was measured usingquantitative real-time PCR in 43 pediatric T-ALL patients. RESULTS: A high level of expression of LMO2, LYL1, TAL1, and BMI1 genes was observed in a large group of T-ALL.Several gene expression signatures indicative of leukemic arrest at specific stages of normal thymocyte development(LYL1 and LMO2) were highly expressed during the cortical and mature stages of T-cell development. Furthermore,upregulated TAL1 and BMI1 expression was observed in all phenotypic subgroups. In all, 6 of the patients had TLX1and TLX3 proto-oncogene expression, which does not occur in normal cells, and none of the patients had CALM-AF10fusion gene transcription. Expression of LYL1 alone and LMO2-LYL1 co-expression were associated with mediastinalinvolvement; however, high-level oncogene expression was not predictive of outcome in the present pediatric T-ALLpatient group, but there was a trend towards a poor prognostic impact of TAL1 and/or LMO2 and/or LYL1 protooncogeneexpression. CONCLUSION: Poor prognostic impact of TAL1 and/or LMO2 and/or LYL1 proto-oncogene expression indicate the needfor extensive study on oncogenic rearrangement and immunophenotypic markers in T-ALL, and their relationship totreatment outcome. CONFLICT OF INTEREST: None declared.

Analysis of Chromosomal Aberrations and FLT3 gene Mutations in Childhood Acute Myelogenous Leukemia Patients.

OBJECTIVE: To identify the well-known common translocations and FLT3 mutations in childhood acute myelogenousleukemia (AML) patients in Turkey. MATERIAL AND METHODS: The study included 50 newly diagnosed patients in which t(15;17), t(8;21), and inv(16)chromosomal translocations were identified using real-time PCR and FLT3 gene mutations were identified via direct PCR amplification PCR-RE analysis. RESULTS: In all, t(15;17) chromosomal aberrations were observed in 4 patients (8.0%), t(8;21) chromosomal aberrationswere observed in 12 patients (24.0%), inv(16) chromosomal aberrations were observed in 3 patients (6.0%), and FLT3-ITD mutations were observed in 2 patients (4.0%); FLT3-D835 point mutation heterozygosity was observed in only 1patient (2.0%) patient. CONCLUSION: Despite of the known literature, a patient with FLT3-ITD and FLT3-D835 double mutation shows a bettersurvival and this might be due to the complementation effect of the t(15;17) translocation. The reportedmutation ratein this article (4%) of FLT3 gene seems to be one of the first results for Turkish population.

Effect and safety of granulocyte transfusions in pediatric patients with febrile neutropenia or defective granulocyte functions.

BACKGROUND: Despite the introduction of new broad-spectrum antibiotics and antifungal therapies over the past decade, infections remains the most frequent cause of death in patients with neutropenia. The aim of this study is to assess the effect and safety of granulocyte transfusions (GTX) for the treatment of severe life-threatening infections in pediatric patients with febrile neutropenia or defective granulocyte functions. METHODS: In this study, 35 pediatric patients with high-risk febrile neutropenia or defective granulocyte functions, who received 111 GTX, were included. GTX were used for 3 consecutive days during infections not responding to antimicrobial therapy. RESULTS: The mean granulocyte content per concentrate was 27.4×109 (min: 4.2×109 to max: 68.4×109) depending on donor's white blood cell count before harvest. GTX were well tolerated in all patients. The infection-related survival rate was 82.4% and overall survival rate was 77.1% at day 30. The overall survival rate was 65.7% and 52% at 3 and 48 months, respectively. CONCLUSIONS: GTX is safe and effective in controlling the life-threatening infections. Further randomized controlled studies with long-term follow-up are needed to assess the exact role of GTX in the outcome of patients with neutropenia and patients with defective granulocyte functions.

Clinical and epidemiological characteristics of pandemic influenza A/(H1N1) in hospitalized pediatric patients at a university hospital, Istanbul, Turkey.

BACKGROUND: The aim of this study was to describe the clinical and epidemiological characteristics of pandemic influenza in hospitalized children. METHODS: A total of 114 patients with suspected H1N1 virus infection were hospitalized, and nasal swabs were sent to National Influenza Reference Laboratory for confirmation of pandemic influenza A (H1N1) virus infection by rRT-PCR assay. RESULTS: Forty-six female and 68 male patients were included in the study. Age of the patients ranged from 40 days to 16 years. Clinical and/or radiological pneumonia were detected in 96% of all. Sixteen patients required mechanical ventilation due to hypoxemia. Previously healthy children required mechanical ventilation and oxygen therapy more than patients with chronic diseases. Elevated levels of CRP and LDH in patients with respiratory distress and patients who required mechanical ventilation were statistically significant. CONCLUSION: Our study showed that progress of pandemic influenza infection in previously healthy children is as severe as their counterparts with chronic underlying diseases.

How to manage an unresectable or recurrent sialoblastoma.

Only 2-5% of all salivary gland tumors occur in children. Sialoblastoma is an extremely rare salivary gland tumor diagnosed at birth or shortly thereafter with significant variability in histological range and clinical course, so that it may be difficult to predict the most appropriate therapy. In cases where surgical removal is not curative or technically feasible, chemotherapy may be attempted. We report herein a patient with progression of a huge partially resected sialoblastoma who was successfully treated with chemotherapy. Systemic chemotherapy with vincristine, actinomycin D, and cyclophosphamide (VAC) seems to be an effective adjuvant or neoadjuvant treatment option for unresectable or recurrent sialoblastoma.

Li-Fraumeni syndrome in a Turkish family.

Li-Fraumeni syndrome (LFS) is one of the familial cancers characterized by different tumors and hereditary TP53 mutations. The adrenocortical carcinoma (ACC) association with acute leukemia is unusual in childhood, even in LFS. The authors here present a family with pR337P mutation in TP53 gene who had a child with acute lymphoblastic leukemia (ALL) and associated adrenocortical carcinoma as a case 1 and his cousin with brain tumor as a case 2. A hereditary TP53 mutation supported the diagnosis of LFS in this family. The patients had many difficulties in treatment strategies and succumbed to death. The availability of a reliable molecular marker to detect the R337P TP53 mutation allows the rapid identification of carriers in families that have a child with ACC. Once identified, carriers could be screened for early detection of ACC by imaging and endocrine studies and should be given psychological support to prevent anxiety for death. Whether early detection of ACC will reduce the mortality in these patients remains to be determined.

Pediatric acute lymphoblastic leukemia complicated by secondary hemophagocytic lymphohistiocytosis.

Hemophagocytic lymphohistiocytosis (HLH) may be familial or secondary to infections, malignancies, metabolic disorders. Infectious causes are mostly viral and EBV is the mostly frequently seen etiologic agent. In this case, we report a child with acute lymphoblastic leukemia (ALL), who had three episodes of secondary HLH, possibly due to two different viral etiologies, namely CMV and RSV together with her malignancy, during her induction-consolidation treatment.

Hematopoietic stem cell transplantation from a donor with Klinefelter syndrome for Wiskott-Aldrich syndrome.

WAS is a rare X-linked recessive disorder characterized by primary progressive T cell immunodeficiency, impaired antipolysaccharide antibody response, thrombocytopenia with small platelet, and eczematoid dermatitis. Untreated patients with typical WAS have poor prognosis with the major causes of death being infection, bleeding, lymphoproliferative disorders, and malignancy. Due to the increased risk of infectious and hemorrhagic episodes the best results with HSCT are achieved in patients less than five yr of age and are recommended as early as possible. Here, we report a three-yr-old boy with WAS who underwent UCB and BMT from his genotypically identical brother with Klinefelter syndrome.

Asymptomatic intracranial hemorrhage in a newborn with congenital factor VII deficiency and successful treatment with recombinant activated factor VII.

Ince Z, Bulut Ö, Tugrul-Aksakal M, Ünüvar A, Devecioglu Ö, Çoban A. Asymptomatic intracranial hemorrhage in a newborn with congenital factor VII deficiency and successful treatment with recombinant activated factor VII. Turk J Pediatr 2018; 60: 562-565. Intracranial hemorrhage is considered the most common cause of death in newborns with congenital factor VII (FVII) deficiency. Recombinant activated FVII (rFVIIa) provides specific replacement therapy, however there is limited experience with its neonatal use. We describe our experience about the treatment of intracranial hemorrhage in a newborn with congenital FVII deficiency and emphasize the importance of imaging in asymptomatic patients. She presented with ecchymoses on her skin, no other pathological clinical signs, prolonged PT, normal PTT and FVII activity of 2%. Intracranial hemorrhage was diagnosed while screening for internal bleedings. Treatment with rFVIIa resulted in stabilization and regression of the hematoma.

Pitfalls in the diagnosis of immune thrombocytopenic purpura in children: 4 case reports.

Acute idiopathic thrombocytopenic purpura is the most common cause of thrombocytopenia in childhood, and diagnosis of idiopathic thrombocytopenic purpura is made clinically based on the exclusion of other causes of thrombocytopenia. Patients with diverse causes of thrombocytopenia are sometimes erroneously diagnosed as having idiopathic thrombocytopenic purpura. However, for the prevention of misdiagnoses, careful inspection of peripheral blood smear is of utmost importance. This report presents 4 cases presumed as acute idiopathic thrombocytopenic purpura that were finally identified as pseudothrombocytopenia, inherited macrothrombocytopenia (MHY9 disorders) possibly Epstein syndrome, Bernard-Soulier syndrome, and drug-induced thrombocytopenia. They draw attention to the importance of platelet morphology to exclude inherited macrothrombocytopenia and history to exclude drug-induced thrombocytopenia. Better diagnostic approaches would be possible by the awareness of these relatively rare causes of isolated thrombocytopenia.

Evaluation of Alpha-Thalassemia Mutations in Cases with Hypochromic Microcytic Anemia: The Istanbul Perspective.

OBJECTIVE: Alpha thalassemia syndromes are caused by mutations on one or more of the four α-globin genes. Mutations could be either more commonly deletional or non-deletional. As some deletions (3.7 and 4.2) cause α+-thalassemia, some cause (-20.5, MED, THAI, FIL) α0 -thalassemia. The aim of this study was to determine alpha thalassemia mutations in patients with unsolved hypochromic microcytic anemia and to evaluate types of mutations. MATERIAL AND METHODS: Two hundred six patients with hypochromic microcytic anemia were evaluated for alpha thalassemia. A venous blood sample of 2 mL was drawn from each patient for DNA isolation. The samples were investigated for α-thalassemia mutations by using the Vienna Lab α-Globlin StripAssay TM commercial kit. RESULTS: Fourteen different mutations were determined in 95 (46.1%) patients. The most common mutation was the 3.7 single gene deletion and was found in 37 patients (n=37/95, 39%). Others common mutations were the 20.5 kb double gene deletion (n=20 patients, 21%), MED double gene deletion (n=17 patients, 17.9%), α2 IVS1 (n=10 patients, 10.5%), α2 cd142 Hb Koya Dora (n=6 patients, 6.3%), α2 polyA1 (Saudi type) (n=6 patients, 6.3%), 4.2 single gene deletion (n=4 patients, 4.2%), α1 cd14 (n=2 patients, 2.1%), and -FIL mutation (n=2 patients 2.1%), respectively. Hb Adana, Hb Icaria, α2 init cd and α2 polyA2 (Turkish type) were found in 1% of the patients (n=1). Seven patients (7.4%) had α-thalassemia triplication. In our study, three mutations (Hb Icaria, α1 cd14, α2 init.cd) were determined firstly in Turkey. Seven mutations (-SEA, -THAI, Hb Constant Spring, α2 cd19, α2 cd59, α2 cd125, Hb Paksé) were not determined in this study. CONCLUSION: Alpha thalassemia should be considered in the differential diagnosis of hypochromic microcytic anemia especially in cases without iron deficiency and b-thalassemia carrier state. Genetic testing should be performed for the suspicious cases. We also recommend that a national database with all mutations in Turkey should be created to screen the alpha thalassemia cost-effectively.

Outcome in neuroblastoma.

OBJECTIVE: To determine outcome of neuroblastoma (NBL) in children under 18 mo of age who had been treated with national protocols. METHODS: The characteristics and treatment outcomes of 27 children were evaluated retrospectively. RESULTS: The event-free survival (EFS) at 60 and 108 mo were 84.7 % ± 7.7 and 72.6 % ± 7.7, respectively. The overall survival (OS) was 91.7 % ± 8 at 108 mo. The only significant risk factor for OS in children with neuroblastoma was the treatment response at the end of therapy (p = 0.001). "Wait and see" policy was applied to two infants with low risk NBL and one infant with stage 4S neuroblastoma and all 3 of these infants have been in remission at last followup. Four of the five patients with MYCN-amplified neuroblastoma were alive at a median follow-up time of 54 mo (range: 5-108 mo). CONCLUSIONS: The EFS and OS of the present group were similar to that of the previous series which included children under 18 mo of age with neuroblastoma. Well known prognostic factors did not affect EFS and OS significantly; this may be related to the retrospective design of the present study and the small number of patients reviewed. High survival rate in infants with MYCN-amplified tumors suggests the difference in the biology of infant neuroblastoma.