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.

Pulmonary Embolism in Childhood: A Multicenter Experience from Turkey

Background: Pulmonary embolism is a clinical condition caused by the obstruction of the pulmonary artery and its branches with endogenous, exogenous embolism, or local thrombus formation. It is a rare but potentially life-threatening event in the pediatric population. Pediatric pulmonary embolism has many unknown characteristics. Aims: To evaluate clinical features, genetic and acquired risk factors, diagnostic imaging, and treatment strategies with long-term results in children with pulmonary embolism. Study Design: A retrospective multicenter clinical trial. Methods: Patients aged 0-18 years who were diagnosed with pulmonary embolism with computed tomography pulmonary angiography (CTPA) findings (intraluminal filling defect in the lobar or main pulmonary artery) in 3 university hospitals between 2006 and 2021 were included in the study. A form was created for data standardization, and variables were collected retrospectively through medical record review. In addition to the features given above, we also evaluated in situ pulmonary artery thrombosis (ISPAT) and patients' Wells scores. Follow-up CTPA results were evaluated for patient response to treatment. Complete recovery means that there were no lesions, incomplete recovery if there was still embolism, and no response if there was no change. Results: Twenty-four patients (female:13, male:11) were included in the study. The mean age was 13.5 years. All patients but one had at least one or more genetic or acquired risk factors. Factor V Leiden mutation (16.6%) was the most common genetic risk factor. Six of 16 patients with Doppler ultrasonography were diagnosed with ISPAT because there was no sign of thromboembolic thrombosis. Nine (41.6%) patients had a Wells score of >4 (pulmonary embolism clinically strong), and 15 (58.4%) patients scored <4 (pulmonary embolism clinically likely weak), indicating that an alternative diagnosis was more likely than pulmonary embolism (sensitivity %37.5). The mean follow-up period was 23 (±17) months. Complete and incomplete recovery was observed in 15 (62.5%) and 7 (29.1%) patients, respectively, among the patients who underwent follow-up evaluation. No response was obtained in 2 patients (8.3%) who died. Conclusion: The Wells scoring system seems insufficient to diagnose pulmonary embolism in children and should be improved by adding new parameters. ISPAT may be more common in children with congenital heart disease and systemic disease.

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.

Impact of the HEAD-US Scoring System for Observing the Protective Effect of Prophylaxis in Hemophilia Patients: A Prospective, Multicenter, Observational Study

Objective: This study aimed to observe the preventive effect of prophylactic treatment on joint health in people with hemophilia (PwH) and to investigate the importance of integration of ultrasonographic examination into clinical and radiological evaluation of the joints. Materials and Methods: This national, multicenter, prospective, observational study included male patients aged ≥6 years with the diagnosis of moderate or severe hemophilia A or B from 8 centers across Turkey between January 2017 and March 2019. Patients were followed for 1 year with 5 visits (baseline and 3th, 6th, 9th, and 12th month visits). The Hemophilia Joint Health Score (HJHS) was used for physical examination of joints, the Pettersson scoring system was used for radiological assessment, point-of-care (POC) ultrasonography was used for bilateral examinations of joints, and the Hemophilia Early Arthropathy Detection with Ultrasound (HEAD-US) score was used for evaluation of ultrasonography results. Results: Seventy-three PwH, of whom 62 had hemophilia A and 11 had hemophilia B, were included and 24.7% had target joints at baseline. The HJHS and HEAD-US scores were significantly increased at the 12th month in all patients. These scores were also higher in the hemophilia A subgroup than the hemophilia B subgroup. However, in the childhood group, the increment of scores was not significant. The HEAD-US total score was significantly correlated with both the HJHS total score and Pettersson total score at baseline and at the 12th month. Conclusion: The HEAD-US and HJHS scoring systems are valuable tools during follow-up examinations of PwH and they complement each other. We suggest that POC ultrasonographic evaluation and the HEAD-US scoring system may be integrated into differential diagnosis of bleeding and long-term monitoring for joint health as a routine procedure.

Traumatic hyphema in a patient with severe hemophilia A: Clinical features and management.

PURPOSE: To describe a case of traumatic hyphema in a patient with severe hemophilia A. CASE: We present a case of a 16-year-old boy with severe hemophilia A who presented to our ophthalmology department with total hyphema and elevated intraocular pressure 3 days after a history of blunt ocular trauma on his right eye. Due to the persistent intraocular pressure elevation and total hyphema despite medical intervention, an early anterior chamber washout was performed with the replacement of factor VIII preoperatively and postoperatively. Re-bleeding or any other complications were not experienced during surgery or postoperatively. At the first postoperative week, 20/20 visual acuity and a normal intraocular pressure without antiglaucoma medication was retained and remained stable during the 6-month follow-up. CONCLUSION: In such cases with hemophilia A, traumatic hyphema, and intraocular pressure elevation despite medical intervention, an early surgical clot removal under intense factor VIII replacement could be performed. In the early postoperative period, factor replacement should be resumed in order to avoid re-bleeding.

Homozygous c.130-131 ins A (pW44X) mutation in the HAX1 gene as the most common cause of congenital neutropenia in Turkey: Report from the Turkish Severe Congenital Neutropenia Registry.

BACKGROUND: Severe congenital neutropenia is a rare disease, and autosomal dominantly inherited ELANE mutation is the most frequently observed genetic defect in the registries from North America and Western Europe. However, in eastern countries where consanguineous marriages are common, autosomal recessive forms might be more frequent. METHOD: Two hundred and sixteen patients with severe congenital neutropenia from 28 different pediatric centers in Turkey were registered. RESULTS: The most frequently observed mutation was HAX1 mutation (n = 78, 36.1%). A heterozygous ELANE mutation was detected in 29 patients (13.4%) in our cohort. Biallelic mutations of G6PC3 (n = 9, 4.3%), CSF3R (n = 6, 2.9%), and JAGN1 (n = 2, 1%) were also observed. Granulocyte colony-stimulating factor treatment was given to 174 patients (80.6%). Two patients died with infectious complications, and five patients developed myelodysplastic syndrome/acute myeloblastic leukemia. The mean (± mean standard error) follow-up period was 129.7 ± 76.3 months, and overall survival was 96.8% (CI, 94.4-99.1%) at the age of 15 years. In Turkey, severe congenital neutropenia mostly resulted from the p W44X mutation in the HAX1 gene. CONCLUSION: In Turkey, mutation analysis should be started with HAX1, and if this is negative, ELANE and G6PC3 should be checked. Because of the very high percentage of consanguineous marriage, rare mutations should be tested in patients with a negative mutation screen.

Glanzmann Thrombasthenia in a Newborn with Heterozygous Factor V Leiden and Heterozygous MTHFR C677T Gene Mutations.

INTRODUCTION: Glanzmann thrombasthenia is a rare congenital platelet dysfunction. CASE CHARACTERISTICS: A 2-day-old male neonate delivered at 35 weeks' gestation was referred with extensive bruising and jaundice. His elder sibling had Glanzmann thrombasthenia, and his mother had thrombophilic risk factors. Flow cytometric analysis revealed absent CD41/CD61. A molecular thrombophilia panel revealed the presence of heterozygous factor V Leiden G1691A and methylenetetrahydrofolate reductase C677T gene mutations. OUTCOME: General precautions to avoid injuries and spontaneous bleeding were advised. MESSAGE: Life-threatening bleeding may not be the first finding in cases of thrombasthenia accompanied by thrombophilic risk factors.

Deferasirox in children with transfusion-dependent thalassemia or sickle cell anemia: A large cohort real-life experience from Turkey (REACH-THEM).

OBJECTIVES: To evaluate the long-term efficacy and safety of deferasirox therapy in a large observational cohort of children with transfusion-dependent thalassemia (TDT) and sickle cell anemia (SCA) in Turkey. METHODS: This was a multicenter, prospective cohort study including TDT and SCA patients aged 2-18 years with iron overload (≥100 mL/kg of pRBC or a serum ferritin [SF] level >1000 µg/L) receiving deferasirox. Patients were followed for up to 3 years according to standard practice. RESULTS: A total of 439 patients were evaluated (415 [94.5%] TDT, 143 [32.6%] between 2 and 6 years). Serum ferritin levels consistently and significantly decreased across 3 years of deferasirox therapy from a median of 1775.5 to 1250.5 µg/L (P < 0.001). Serum ferritin decreases were noted in TDT (1804.9 to 1241 µg/L), SCA (1655.5 to 1260 µg/L), and across age groups of 2-6 years (1971.5 to 1499 µg/L), 7-12 years (1688.5 to 1159.8 µg/L), and 13-18 years (1496.5 to 1107 µg/L). Serum ferritin decreases were also noted for all deferasirox dose groups but only significant in patients with doses ≥30 mg/kg/d (n = 120, -579.6 median reduction, P < 0.001). Only 9 (2%) patients had adverse events suspected to be related to deferasirox. Serum creatinine slightly increased but remained within the normal range. CONCLUSIONS: Deferasirox has long-term efficacy and safety in children with TDT and SCA, although higher doses (≥30 mg/kg/d) may be required to achieve iron balance.

Coexistence of Kasabach-Merritt Syndrome and placental chorioangioma in a premature infant.

Kasabach-Merritt syndrome is a rare life-threatening clinical presentation in neonatal period. it is characterized by giant hemangioma and serious thrombocytopenia. The diagnostic criteria include: 1) hemangiomas on skin, 2) thrombocytopenia or coagulopathy, 3) hemangioma on internal organs diagnosed by ultrasonography, computed tomography or magnetic resonance imaging, and 4) excluding reasons, such as idiopathic thrombocytopenic purpura or hypersplenism.Placental chorioangiomas are the most widespread non-trophoblastic benign tumor-like lesions of placenta. The clinical signs are associated with tumor size. Chorioangiomas larger than 4-5 cm may lead to various maternal and fetal complications.Here, a female premature infant was diagnosed with placental chorioangioma and liver hemangioma during antenatal period. She developed heart failure secondary to non-immune hydrops fetalis in the neonatal period. The atypical giant hemangioma and coagulopathy suggested the diagnosis of Kasabach-Merritt syndrome. The macroscopic and histopathological examination of the placenta confirmed the diagnosis of chorioangioma. The patient died due to purpura fulminans despite the treatment with prednisolone and propranolol that was started on the second day of life. We are presenting this rare case where placental chorioangioma leading to non-immune hydrops fetalis co-existed with Kasabach-Merritt syndrome.

Juvenile Myelomonocytic Leukemia in Turkey: A Retrospective Analysis of Sixty-five Patients.

OBJECTIVE: This study aimed to define the status of juvenile myelomonocytic leukemia (JMML) patients in Turkey in terms of time of diagnosis, clinical characteristics, mutational studies, clinical course, and treatment strategies. MATERIALS AND METHODS: Data including clinical and laboratory characteristics and treatment strategies of JMML patients were collected retrospectively from pediatric hematology-oncology centers in Turkey. RESULTS: Sixty-five children with JMML diagnosed between 2002 and 2016 in 18 institutions throughout Turkey were enrolled in the study. The median age at diagnosis was 17 months (min-max: 2-117 months). Splenomegaly was present in 92% of patients at the time of diagnosis. The median white blood cell, monocyte, and platelet counts were 32.9x109/L, 5.4x109/L, and 58.3x109/L, respectively. Monosomy 7 was present in 18% of patients. JMML mutational analysis was performed in 32 of 65 patients (49%) and PTPN11 was the most common mutation. Hematopoietic stem cell transplantation (HSCT) could only be performed in 28 patients (44%), the majority being after the year 2012. The most frequent reason for not performing HSCT was the inability to find a suitable donor. The median time from diagnosis to HSCT was 9 months (min-max: 2-63 months). The 5-year cumulative survival rate was 33% and median estimated survival time was 30±17.4 months (95% CI: 0-64.1) for all patients. Survival time was significantly better in the HSCT group (log-rank p=0.019). Older age at diagnosis (>2 years), platelet count of less than 40x109/L, and PTPN11 mutation were the factors significantly associated with shorter survival time. CONCLUSION: Although there has recently been improvement in terms of definitive diagnosis and HSCT in JMML patients, the overall results are not satisfactory and it is necessary to put more effort into this issue in Turkey.

A National Registry of Thalassemia in Turkey: Demographic and Disease Characteristics of Patients, Achievements, and Challenges in Prevention.

OBJECTIVE: The Turkish Society of Pediatric Hematology set up a National Hemoglobinopathy Registry to demonstrate the demographic and disease characteristics of patients and assess the efficacy of a hemoglobinopathy control program (HCP) over 10 years in Turkey. MATERIALS AND METHODS: A total of 2046 patients from 27 thalassemia centers were registered, of which 1988 were eligible for analysis. This cohort mainly comprised patients with ß-thalassemia major (n=1658, 83.4%) and intermedia (n=215, 10.8%). RESULTS: The majority of patients were from the coastal areas of Turkey. The high number of patients in Southeastern Anatolia was due to that area having the highest rates of consanguineous marriage and fertility. The most common 11 mutations represented 90% of all ß-thalassemia alleles and 47% of those were IVS1-110(G->A) mutations. The probability of undergoing splenectomy within the first 10 years of life was 20%, a rate unchanged since the 1980s. Iron chelators were administered as monotherapy regimens in 95% of patients and deferasirox was prescribed in 81.3% of those cases. Deferasirox administration was the highest (93.6%) in patients aged <10 years. Of the thalassemia major patients, 5.8% had match-related hemopoietic stem cell transplantation with a success rate of 77%. Cardiac disease was detected as a major cause of death and did not show a decreasing trend in 5-year cohorts since 1999. CONCLUSION: While the HCP has been implemented since 2003, the affected births have shown a consistent decrease only after 2009, being at lowest 34 cases per year. This program failure resulted from a lack of premarital screening in the majority of cases. Additional problems were unawareness of the risk and misinformation of the at-risk couples. In addition, prenatal diagnosis was either not offered to or was not accepted by the at-risk families. This study indicated that a continuous effort is needed for optimizing the management of thalassemia and the development of strategies is essential for further achievements in the HCP in Turkey.

Differences in Granule Morphology yet Equally Impaired Exocytosis among Cytotoxic T Cells and NK Cells from Chediak-Higashi Syndrome Patients.

Chediak-Higashi syndrome (CHS) is caused by autosomal recessive mutations in LYST, resulting in enlarged lysosomal compartments in multiple cell types. CHS patients display oculocutaneous albinism and may develop life-threatening hemophagocytic lymphohistiocytosis (HLH). While NK cell-mediated cytotoxicity has been reported to be uniformly defective, variable defects in T cell-mediated cytotoxicity has been observed. The latter has been linked to the degree of HLH susceptibility. Since the discrepancies in NK cell- and T cell-mediated cellular cytotoxicity might result from differences in regulation of cytotoxic granule release, we here evaluated perforin-containing secretory lysosome size and number in freshly isolated lymphocytes from CHS patients and furthermore compared their exocytic capacities. Whereas NK cells from CHS patients generally contained a single, gigantic perforin-containing granule, cytotoxic T cells predominantly contained several smaller granules. Nonetheless, in a cohort of 21 CHS patients, cytotoxic T cell and NK cell granule exocytosis were similarly impaired upon activating receptor stimulation. Mechanistically, polarization of cytotoxic granules was defective in cytotoxic lymphocytes from CHS patients, with EEA1, a marker of early endosomes, mislocalizing to lysosomal structures. The results leads to the conclusion that lysosome enlargement corresponds to loss of distinct organelle identity in the endocytic pathway, which on a subcellular level more adversely affects NK cells than T cells. Hence, vesicular size or numbers do not per se dictate the impairment of lysosomal exocytosis in the two cell types studied.

Isotypic analysis of antibodies against activated Factor VII in patients with Factor VII deficiency using the x-MAP technology.

While the immune response to hemophilic factors in hemophilia has been widely studied, little is known about the development of anti-Factor VII (FVII) antibodies in FVII deficiency. We developed a robust technique based on the x-MAP technology to detect the presence of antibodies against FVII and characterize their isotype and validated this method using blood samples from 100 patients with FVII deficiency (median FVII clotting activity [FVII:C]: 6%) and 95 healthy controls. Anti-FVII antibodies were detected in patients but also in some controls, although the concentration of total immunoglobulin G (IgGt) and IgG1 and IgG4 subclasses was significantly different between groups. The IgG1 subclass concentrations remained significantly different also when only untreated patients were compared with controls. This difference could partially be related to the F7 genotype, particularly in patients harboring the p.Arg139Gln mutation. This x-MAP-based method might be useful for assessing the immunogenicity of novel FVII compounds and of activated FVII (FVIIa) concentrates. Further prospective studies are needed to better understand the clinical relevance of these antibodies in the management of patients with FVII deficiency.

Novel plasminogen gene mutations in Turkish patients with type I plasminogen deficiency.

The plasminogen (Plg) protein is the inactive proenzyme form of plasmin that dissolves fibrin thrombi by a process called fibrinolysis. It has been shown that homozygous or compound-heterozygous deficiency of this protein is a major cause of a rare inflammatory disease affecting mainly mucous membranes found in different body sites. In this study, five individual Turkish patients and nine Turkish families with type 1 Plg deficiency were investigated for PLG gene mutations. All of the coding regions of the PLG gene mutations were screened for mutations using denaturing high-pressure liquid chromatography (DHPLC). Samples showing a different DHPLC profile were subjected to DNA sequencing analysis. Here, we described five novel mutations namely, Cys49Ter, +1 IVS6 G>A, Gly218Val, Tyr283Cys, and Gly703Asp. Previously identified five nonsynonymous (Lys38Glu, Glu180Lys, Gly420Asp, Asp453Asn, Pro763Ser), five synonymous (330 C>T, 582 C>T, 771 T>C, 1083 A>G, 2286 T>G), and a 3' untranslated region (3' UTR) mutation (c.*45 A>G) were also reported in this present study. In this study, we have identified a total of eight mutations, five of which are novel. The mutations/polymorphisms identified in eight of the patients do not explain the disease phenotype. These cases probably carry other pathological mutations (homozygous or compound heterozygous) that cannot be detected by DHPLC.

Ophthalmic manifestations in recently diagnosed childhood leukemia.

PURPOSE: To determine the prevalence and the pattern of ocular involvement in children with leukemia at the time of diagnosis. METHODS: The data of patients with leukemia who underwent complete ophthalmic examination at the time of diagnosis between January 2005 and December 2014 were retrospectively reviewed. Demographic data, type of leukemia, ocular findings, blood parameters, and duration of follow-up were analyzed. RESULTS: A total of 185 patients (111 male and 74 female) were included in the study, with a median age of 6.0 years (range 0.5-18.0 years) and a median follow-up time of 36.0 months (range 0.5-108.0 months). Ocular signs were present in 24.3% of the patients at the time of diagnosis and 37.8% of them were symptomatic. The prevalence of ocular involvement was 20.4% in patients with acute lymphocytic leukemia (ALL) and 36.4% in patients with acute myelocytic leukemia (AML) (p = 0.051). Fatality rate was significantly higher in subjects with AML compared with ALL (p = 0.019), but was not significantly different between patients with and without ocular involvement (p = 0.166). There were no significant differences in hemoglobin levels, white blood cell counts, or platelet counts between patients with ALL and AML. Platelet counts were significantly lower in patients with ocular signs compared with subjects without ocular involvement (p = 0.012), while hemoglobin levels and white blood cell counts did not differ significantly. CONCLUSIONS: Various ocular signs may be present at the time of diagnosis in childhood leukemia, even in patients without any symptoms. Routine ophthalmic examination should be performed in recently diagnosed children with leukemia.

Effects of Prednisolone, L-Asparaginase, Gemfibrozil, and Combinations of These Elements on Mice Lipid Profile, Liver, and Pancreas.

The aim of this study is to determine the effects of L-asparaginase (L-ASP), corticosteroids (CSs), and antilipidemics, separately and in combination, on the lipid profiles and the liver and pancreas histology in mice. This study included 8 groups of 7 mice each. Before any drug administration, serum samples were taken from all of the mice. Then, normal saline was applied to the control group, and a medication or combination of medications was applied to the other groups. Levels of triglycerides, cholesterol (COL), and high-density lipoprotein (HDL) and low-density lipoprotein (LDL) were determined, and the livers and pancreases were evaluated histologically at the end of the study. Triglycerides increased significantly in the CS-only and the L-ASP-only groups, COL increased significantly in the CS-only group, and HDL increased significantly in the CS-only and the antilipidemic-only groups. LDL was significantly lower in the CS-only and the L-ASP-only groups. CSs and L-ASP were significantly effective in liver necrosis, L-ASP was significantly effective in liver balloon degeneration, and CS were significantly effective in pancreas vacuolization. Triglyceride measurement is recommended before/during CS and/or L-ASP treatment. Starting with an antilipidemic agent can be considered to avoid possible complications in patients with significantly high rates. Indicators of a possible liver or pancreas injury should also be considered.

Infectious diseases, autoimmunity and midline defect in a patient with a novel bi-allelic mutation in IL12RB1 gene.

Clinical disease caused by weakly pathogenic mycobacterial species, which is known as Mendelian susceptibility to mycobacterial disease (MSMD), is a rare entity. IFN-γ and IL-17 production are defective due to insufficient response to IL-2 and IL-23 in IL-12Rß1 deficiency; so this also causes tendency to intracellular microorganisms and candidal diseases. Here, we present a patient who suffers IL-12Rß1 deficiency caused by a novel bi-allelic mutation with recurrent salmonellosis, mycobacterial, fungal infections and remained asymptomatic during 13 months of follow-up after hIFN-γ treatment. In addition she had hemolytic anemia and midline defects like cleft lip and palate which have not been reported in a patient with MSMD in the literature prior to this case report. In conclusion, diagnosis of MSMD should be kept in mind in patients with recurrent salmonellosis, mycobacterial and fungal infections especially in countries with a high consanguinity rate.

Essential thrombocythemia with Mpl W515 K mutation in a child presenting with Budd-Chiari syndrome.

Essential thrombocythemia (ET) is an extremely rare childhood disorder characterised by clonal expansion of megakaryocytic lineage in bone marrow, leading to a persistent increase in the number of circulating thrombocytes and thus increased risk for thrombotic and haemorrhagic events. The molecular mechanisms of ET are not fully understood. Most children with ET have the JAK2 V617F somatic mutation; however, another mutation, involving a W to L or K substitution at Mpl codon 515, was reported in a small proportion of adult ET patients that is extremely rare in children. Herein, we describe a Mpl W515K somatic mutation in a paediatric case of ET who presented with Budd-Chiari syndrome. No paediatric patient harbouring a Mpl W515K mutation has been previously reported.

Novel mutations of integrin αIIb and ß3 genes in Turkish children with Glanzmann's thrombasthenia.

Glanzmann's thrombasthenia (GT) is an inherited disorder of platelet aggregation, characterized by qualitative and quantitative defect on platelet αIIbß3 integrin (GpIIb/IIIa), resulting in lifelong bleeding tendency due to defective platelet plug formation. The αIIb gene (ITGA2B) and ß3 gene (ITGB3) are closely located at chromosome 17q21.31-32. ITGA2B consist of 30 exons and encoding α chain, whereas ITGB3 has 15 exons and encoding ß chain. Until now, according to the Human Gene Mutation Database (HGMD), 138 mutations at ITGA2B gene and 101 mutations at ITGB3 gene have been identified. We aimed to determine whether there was any mutation in the ITGA2B and ITGB3 genes, and a correlation between clinical phenotype and genotype in Turkish GT patients. We examined 20 patients with GT followed at the Department of Pediatric Hematology, Meram Faculty of Medicine, for Clinical and Laboratory Findings and Molecular Genetic Analysis. Peripheral blood was collected from patients, and a written informed consent for genetic analysis was obtained from parents. DNA was isolated from by proteinase K and phenol/chloroform extraction. ITGA2B and ITGB3 genes were screened by polymerase chain reaction. There were 12 females and 8 males with a median age of 15.25 years. Major clinical presentations of these patients were mucocutaneous bleedings. The most common bleeding type was epistaxis (85%). Life-threatening bleedings were seen in five patients. Seven (35%) patients showed various mutations in the ITGA2B or ITGB3 genes. We detected four novel mutations in three different regions and two mutations defined previously within the ITGA2B gene. These changes are at exon 4; c.570 T > G alteration, at exon 13 c.1277 T > A, c.1291 T > G alterations, at exon 19 c.1921A > G alterations. And from the start point of exon 14, behind 107 bases, we detected a heterozygous alteration at Thymine to Guanine. According to PolyPhen Database Program and NCBI Multiple Alignment Tool Database, four transitions are conserved at evolutionary process, so we can say that these transitions are novel mutations. c. 468T > G alteration at exon 4 and c. 1378 T > A alteration at exon 13 were reported to HGMD previously. Screening the exons of the ITGB3 gene from the same patient groups, we reported a novel missense mutation at exon 5, at nucleotide 680. No correlation was found between clinical phenotype and genotype. These mutations were described for the first time in Turkish population, and all novel mutations are not defined previously. Furthermore, collaborative studies are needed for the population point of view.