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.

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 β-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 β-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.

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.

Difficult diagnosis of invasive fungal infection predominantly involving the lower gastrointestinal tract in acute lymphoblastic leukaemia

Invasive fungal infections are most commonly seen in immunocompromised patients and usually affect the respiratory system. Gastrointestinal system involvement of mucormycosis and invasive aspergillosis is rarely reported in childhood. Here we describe a 5 year old boy with acute lymphoblastic leukaemia who developed invasive fungal infection particularly affecting the lower gastrointestinal system to emphasise the difficulties in diagnosis and management of invasive fungal infections in immunocompromised patients.

Frequency of red cell allo- and autoimmunization in patients with transfusion-dependent beta thalassemia and affecting factors

In this study, we aimed to determine the frequency of red cell allo- and autoimmunization and analyze the factors responsible for the development of antibodies in patients with transfusion-dependent thalassemia. This crosssectional study was conducted on 139 patients with thalassemia major and intermedia who received leukodepleted RBC transfusions on a regular basis. Patients with a positive antibody screen were further tested for antibody identification by a gel method. Red cell alloantibodies were found in 9 (6.4%) patients, and autoantibodies were found in 17 (12.2%) patients. The most common alloantibodies detected were those against Rh and Kell antigen systems. The alloantibody development rate was higher in thalassemia intermedia patients, in Rh(-) patients, in patients with an initial transfusion age >2 years and in patients with a transfusion interval >3 weeks (p<0.05). The autoantibody development rate was found to be higher in adult and splenectomized patients (p<0.05). Data from this study demonstrate that the RBC antibody development rate is high in our region. RBC antigen phenotyping and crossmatching with Kell and Rh subgroups may reduce alloimmunization in chronically transfused beta-thalassemia patients.

Central nervous system involvement of epstein barr virus associated lymphoproliferative disorder in a child with acute lymphoblastic leukemia: successful treatment with rituximab and interferon-alpha

Central nervous system (CNS) involvement of Epstein-Barr virus (EBV)-associated lymphoproliferative disease is a rare and serious complication in children with leukemia. Although rituximab therapy seems to be promising in these cases, persistent hypogammaglobulinemia may appear after treatment due to complete depletion of normal B lymphocytes in the peripheral blood. Here we report isolated CNS involvement of EBV-associated lymphoproliferative disorder in a 4-year-old boy with acute leukemia. The patient was treated with rituximab and interferon alpha; however, persistent hypogammaglobulinemia developed as a complication. Given the rarity of the complication in children receiving these agents, our experience with such a case may be helpful to others.

Conflict of interest:None declared.

Nutritional B12 Deficiency in Infants of Vitamin B12-Deficient Mothers

Aim: Nutritional vitamin B12 deficiency in infants may occur because the maternal diet contains inadequate animal products. Clinical presentations of the infants who had nutritional vitamin B12 deficiency were analyzed in this study. Subjects and Methods: Patients with nutritional vitamin B12 deficiency were enrolled in the study between 2003 and 2010. The diagnosis was based on a nutritional history of mothers and infants, clinical findings, hematological evaluation, and low level of serum vitamin B12. Results: Thirty children aged 1 - 21 months constituted the study group. Poverty was the main cause of inadequate consumption of animal products of the mothers. All infants had predominantly breastfed. The most common symptoms were developmental delay, paleness, apathy, lethargy, anorexia, and failure to thrive. Hematological findings were megaloblastic anemia (83.3 %), thrombocytopenia (30 %), and severe anemia (13.3 %). All of the mothers had low serum B12 levels; eight of them had megaloblastic anemia. Conclusion: The unusual clinical manifestations of vitamin B12 deficiency may also be seen apart from neurological and hematological findings. Nutritional vitamin B12 deficiency due to maternal deficiency might be a serious health problem in infants. Therefore, screening and supplementation of pregnant and lactating women to prevent infantile vitamin B12 deficiency should be considered.

Mutation of the proton-coupled folate transporter gene (PCFT-SLC46A1) in Turkish siblings with hereditary folate malabsorption

Hereditary folate malabsorption (HFM) is a rare autosomal recessive disorder characterized by systemic and central nervous system folate deficiency. Turkish siblings are reported with the clinical syndrome of HFM, homozygous for deletion of 2 bases (c.204_205 delCC) within the first exon of the proton-coupled folate transporter (PCFT) gene, causing a frameshift. Low blood and cerebrospinal fluid folate levels were detected at ages 3.5 and 1 month. Treatment with parenteral 5-formyltetrahydrofolate resulted in normal development now at ages 3 and 1 year. Extending current knowledge on the phenotypic manifestations of HFM and the PCFT mutation spectrum will provide opportunities to define possible genotype-phenotype correlations and clarify the basis for the phenotypic variability that is characteristic of this disorder.

Reticular dysgenesis in a preterm infant: a case report

Reticular dysgenesis (RD) is a rare congenital immunodeficiency classified within the severe combined immunodeficiencies (SCIDs) and characterized by impairment of both lymphoid and myeloid cell development. Neutropenia unresponsive to recombinant human granulocyte colony-stimulating factor (rGCSF) is the hallmark of RD and the clinical course is rapidly fatal due to overwhelming infections. The authors report a female newborn at 32 weeks of gestation presenting with severe leukopenia at birth. The bone marrow showed a maturation arrest in the myeloid and lymphoid lineage. She had no response to granulocyte colony stimulating factor (rGCSF) treatment and died with sepsis at age of 2 months.

Hyperleukocytosis in childhood acute lymphoblastic leukemia: complications and treatment outcome

Hyperleukocytosis, defined as a peripheral leukocyte count ≥ 100x109/L, is seen in 5-20% of newly diagnosed cases of childhood leukemia and is a poor prognostic factor. In this study, we aimed to examine the presenting clinical and laboratory features, complications, and treatment outcome of 47 children with acute lymphoblastic leukemia (ALL) and hyperleukocytosis who were diagnosed and treated in four medical centers of İzmir between January 1990 and January 2001. The median age was 5.0 years (range: 0.1-16.3 years). Median white blood cell count was 495x109/L (range: 107x109/L- 794x109/L). Forty-two of 47 patients (90%) had hepatosplenomegaly, 5 (11%) had respiratory distress, 3 (6%) had neurologic symptoms, 3 (6%) had diffuse cervical lymphadenopathy, and 3 (6%) had acute renal failure at admission. Ten of 47 patients (21%) had central nervous system involvement, and 17 (36%) had mediastinal mass. Ten patients (21%) had coagulopathy and 15 patients (32%) had metabolic complications (8 patients had hyperuricemia, 4 had hyperphosphatemia, 2 had hyperuricemia, hyperphosphatemia and hypercalcemia, and 1 had hypocalcemia) before the initiation of therapy. Forty of 47 patients (85%) with hyperleukocytosis were effectively managed with intravenous hydration, alkalinization, and allopurinol therapy. Early death during remission induction therapy occurred in 5 patients (11%) with respiratory distress and sepsis. Kaplan-Meier estimates of event free survival and overall survival were 37.0% and 40.5%, respectively.

Life-threatening mediastinal-retroperitoneal hemorrhage in a child with moderate hemophilia A and high inhibitor titer: successful management with recombinant activated factor VII

The authors describe an 11-year-old boy with hemophilia A and high titer inhibitor who developed a life-threatening mediastinal-retroperitoneal hemorrhage. Chest CT showed a large hematoma beginning in the retrotracheal area, filling the mediastinum, compressing the carina, and extending retroperitoneally up to the kidneys. As the surgical approach has a high mortality rate, the authors chose a more conservative approach initially and obtained excellent bleeding control with recombinant activated factor VII without the need for surgical intervention. As reported in other patients, the authors also showed a decrease in the factor III inhibitor while this patient was successfully treated with bypassing agents.

Role of transforming growth factor-beta 1 gene polymorphisms in childhood idiopathic thrombocytopenic purpura

PURPOSE

To investigate whether transforming growth factor-beta 1 (TGF-beta 1) gene polymorphisms have a role in the development, clinical progress, and treatment response in children with idiopathic thrombocytopenic purpura (ITP).

PATIENTS AND METHODS

Thirty-five children with acute ITP, 40 children with chronic ITP, and 97 healthy children were enrolled. After genomic DNA was extracted, TGF-beta 1 gene 509 (C-->T), codon 25 (Arg-->Pro), and codon 10 (Leu-->Pro) polymorphisms were studied using a coupled polymerase chain reaction-restriction enzyme digestion method.

RESULTS

The genotype and allele frequencies of TGF-beta 1 polymorphisms between acute ITP, chronic ITP, and control group did not differ significantly. No significant association was found between TGF-beta 1 polymorphisms and therapy response.

CONCLUSIONS

These results demonstrate that the frequency of TGF-beta1 gene 509 (C-->T), codon 25 (Arg-->Pro), and codon 10 (Leu-->Pro) polymorphisms and alleles do not play a role as a genetic risk factor in the development and clinical progress of ITP. Different results may be obtained with further studies involving larger patient populations and other TGF-beta 1 gene polymorphisms.

Plasma transforming growth factor beta1 levels in thrombocytopenic and nonthrombocytopenic neonates

In this study, we determined the plasma TGF-beta1 levels in healthy and thrombocytopenic and nonthrombocytopenic neonates who had perinatal risk factors and examined the association between plasma TGF-beta1 levels and platelet counts in these newborns to investigate the role of TGF-beta1 in the pathogenesis of neonatal thrombocytopenia. Three groups were defined in this prospective study: group 1, thrombocytopenic neonates (n=22) who had perinatal risk factors; group 2, nonthrombocytopenic neonates who had similar perinatal risk factors for thrombocytopenia (n=20); group 3, healthy and nonthrombocytopenic neonates without any risk factors (n=20). Plasma TGF-beta1 levels were measured with ELISA. Plasma TGF-beta1 levels of the thrombocytopenic neonates were significantly lower than those of healthy nonthrombocytopenic neonates but did not differ significantly from nonthrombocytopenic neonates who had similar perinatal risk factors for thrombocytopenia. There was a significant positive correlation between plasma TGF-beta1 levels and platelet counts. Further studies are needed to determine the cause of low plasma TGF-beta1 levels in thrombocytopenic neonates and to investigate the role of plasma TGF-beta1 levels in the pathogenesis of neonatal thrombocytopenia.

Investigation of megakaryocyte apoptosis in children with acute and chronic idiopathic thrombocytopenic purpura

OBJECTIVE

Although the platelet destruction shows a primary role in the thrombocytopenia of idiopathic thrombocytopenic purpura (ITP), it has been demonstrated that impaired platelet production may also contribute to the severity of thrombocytopenia in ITP. The present study examined megakaryocyte apoptosis in bone marrow aspirates of children with acute and chronic ITP and investigated the role of megakaryocyte apoptosis in ITP pathophysiology.

METHODS

Thirteen children diagnosed with acute ITP and eight children diagnosed with chronic ITP comprised the study group. Ten children, who were hospitalized for scoliosis operation but healthy otherwise, comprised the control group. In all children, megakaryocytes were isolated from the same amount of bone marrow aspirate samples using MACS CD61 MicroBeads (Miltenyl Biotec, Auburn, CA, USA). Megakaryocyte apoptosis was studied with transferase-mediated d-UTP-bitin nick end-labeling method.

RESULTS

Isolated megakaryocyte counts did not differ significantly between acute ITP, chronic ITP and control groups. The percentage of apoptotic megakaryocytes did not differ significantly between acute ITP group and control group and between chronic ITP group and control group. The percentage of apoptotic megakaryocytes in patients with chronic ITP was significantly lower than the patients with acute ITP. There was no correlation between the percentage of apoptotic megakaryocytes and platelet counts of the cases.

CONCLUSIONS

Increased megakaryocytic apoptosis does not play a role in the pathogenesis of dysmegakaryopoiesis and impaired platelet production in children with ITP. Decreased megakaryocyte apoptosis in cases with chronic ITP may be due to suppression of megakaryocyte maturation, as the terminal phase of the megakaryocyte lifespan is characterized by the onset of apoptosis.

Neutrophil apoptosis in patients with beta-thalassemia major

Increased susceptibility to infection is reported in patients with beta-thalassemia major due to toxic effect of iron on neutrophil functions and reticuloendothelial system dysfunction. This study investigated the association between the neutrophil apoptosis and frequency of infection episodes, desferrioxamine treatment, and serum ferritin levels in patients with beta-thalassemia major. A total of 35 children diagnosed with beta-thalassemia major were enrolled. Group 1 consisted patients who were receiving desferrioxamine (DFO) and group 2 consisted of patients who did not start to receive DFO. A total of 15 healthy children were enrolled to serve as a control group. Frequency of infection episodes within a year was noted from hospital records. In all patients, the same method based on flow cytometry (annexin V labeled with FITC) was used to assess neutrophil apoptosis. Neutrophil count and percentage of apoptotic neutrophils did not differ significantly between the groups. When frequency of infection episodes among groups was evaluated, frequency of infection episodes of the patients who were receiving DFO was significantly higher than in the other groups. When correlation between neutrophil apoptosis and frequency of infection episodes, serum ferritin levels, and neutrophil count of the patients was analyzed according to groups, no significant correlation was found. The results indicate that high serum ferritin level and DFO use in patients with beta-thalassemia major do not enhance neutrophil apotosis in vivo and enhanced neutrophil apoptosis cannot be a possible cause for increased susceptibility to infections in these patients.

A pediatric case of lymphomatoid granulomatosis with onset after completion of chemotherapy for acute myeloid leukemia

In this case report, we present a pediatric case of lymphomatoid granulomatosis (LG) with onset just after the completion of chemotherapy for childhood acute myeloid leukemia (AML). After the completion of maintenance therapy, the patient was admitted to our clinic with a complaint of cough. Radiologic examinations revealed nodular lesions in lungs, liver, and kidney. His bone marrow was in remission. The histopathologic examination of the open lung biopsy was consistent with LG. He received only one cycle of cyclophosphamide and high-dose methyl prednisolone treatment and continued to receive interferon (IFN) alpha-2b therapy for 18 months. This treatment regimen resulted in an excellent response. In conclusion, LG may occur after the treatment of pediatric AML as a rare complication and IFN alpha-2b may be an effective treatment choice in these patients.

Autoimmune lymphoproliferative syndrome: report of two cases and review of the literature

Autoimmune lymphoproliferative syndrome (ALPS) is a rare disease occurring in childhood. Recently, it has been shown that heritable mutations in Fas or Fas ligand genes, which regulate lymphocyte survival by triggering apoptosis of lymphocytes, are the most frequent cause of ALPS. Patients with ALPS frequently have lymphadenopathy, splenomegaly and hepatomegaly, especially at young ages. A positive result of the Direct Coomb's test, autoimmune hemolytic anemia, and idiopathic thrombocytopenic purpura are the most common features of autoimmunity in patients with ALPS. Elevated numbers and percentages (>1%) of double-negative (CD4-CD8-) T cells, and characteristic pathologic findings in lymph nodes or spleen are other important diagnostic features. In this report, we present the clinical, immunologic, and pathologic features of two children who were diagnosed with ALPS. The early recognition of ALPS in children with enlarged lymph nodes, hepatosplenomegaly, and autoimmune hematologic features has important diagnostic and prognostic value in avoiding expensive and time-consuming studies and unnecessary treatments. The ratio of CD4-CD8- T cells, immunoglobulin levels and the histopathologic features of lymph nodes should be rapidly determined in these patients in order to establish an early diagnosis and treatment.

Treatment outcome of adolescents with acute lymphoblastic leukemia

Despite intensified chemotherapy, adolescents with acute lymphoblastic leukemia (ALL) still have lower rates of survival than younger children. The purpose of our study was to compare the treatment outcome and presenting clinical and laboratory features of adolescent and younger children with newly diagnosed ALL who were treated at our pediatric hematology department. Between April 1991 and February 2000, 42 children up to 18 years of age who were newly diagnosed with ALL and treated adequately with modified ALL Berlin-Frankfurt-Münster (BFM) 90 or 95 protocols were included in this study. The patients were examined in two groups according to their ages: the first group consisted of children who were <14 years old and the second group consisted of adolescents who were >14 years old. The median age of 42 patients was 6.5 years (range: 1-16.5 years); 26% of the patients were adolescents. The results of this study demonstrated that after a median observation time of 6 years the overall survival (OS) and event-free survival (EFS) of patients who were <14 and >14 years of age were 75% vs 49% and 70% vs 40%, respectively. When adolescent and younger patients were compared to each other according to gender, WBC count at administration, French-American-British (FAB) classification, immunophenotypes, risk groups, early deaths, and relapse rates, there were no statistically significant differences. Comparative data from other studies and data from this study indicate that adolescents with ALL still have shorter OS and EFS than younger children and a steady improvement in treatment outcome for adolescents with ALL over time suggests that more intensive therapy favorably influences prognosis.

Polycythemia vera in a 12-year-old girl: a case report

A case of a 12-year-old girl presenting with headache and splenomegaly and fulfilling the diagnostic criteria of polycythemia vera is reported. Her peripheral blood values were as follows: hemoglobin 18 g/dL, red blood cells 7,000,000/mm3, while blood cells 22,000/mm, and platelets 1,248,000/mm3. Phlebotomy was performed initially but was ineffective. Afterward 100 mg/kg per day aspirin and 30/mg/kg per day hydroxyurea were given. The patient has been asypmtomatic for 1 year and her recent hemoglobin level is 15.5 g/dL, platelet count 922,000/mm3, and white blood cell 12,800/mm3. Polycythemia vera is an extremely uncommon disease in childhood and for this reason its treatment is not well established.

Oral cyclic megadose methylprednisolone therapy for chronic immune thrombocytopenic purpura in childhood

The objectives of this study were to investigate the effectiveness of oral megadose methylprednisolone (OMMP) therapy in children with chronic immune thrombocytopenic purpura (ITP). Twenty-two patients were given oral methylprednisolone daily for 7 d (30 mg/kg for 3 d and then 20 mg/kg for 4 d). OMMP therapy was repeated once per month if the platelet count was less than 20,000/mm3 at the 30th day of therapy, for up to six courses. The number of platelets of all patients increased gradually during the OMMP therapy, with a peak number at the 7th day, then decreased until the 14th day, and remained relatively stable until 12 months. During the study no patient had a platelet count less than 20,000/mm3 at the 3rd day and 50,000/mm3 at the 7th day. Although the number of platelets was gradually decreased between the 7th and 14th days, it remained above 100,000/mm3 for at least 12 months in the nine patients, and above 20,000/mm3 in the four patients. None of these 13 patients required hospitalization or therapy during the follow-up period. All of the patients tolerated the medication well. None of them reported side-effects that were severe enough to discontinue therapy. We conclude that OMMP therapy is a safe, easy and effective therapy in children with refractory chronic ITP, and it may provide long-term remission in about two thirds of the patients.