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.

Effect of serum panel reactive antibodies on allogeneic hematopoietic stem cell transplantation in pediatric thalassemia patients: A single-center experience.

BACKGROUND: The aim of this study was to assess the impact of serum panel reactive antibodies (PRA) on the outcomes of allogeneic hematopoietic stem cell transplantation (HSCT) in pediatric thalassemia patients. METHODS: A total of 73 pediatric patients with thalassemia were included in this single-center study. Pre-transplant PRA levels were evaluated, and the patients were divided into two groups: PRA-negative (group 1; n = 44) and PRA-positive (group 2; n = 29). Patient characteristics, including age, gender, donor type, stem cell source, and HLA compatibility, were analyzed. Transplant outcomes, including engraftment, transfusion requirements, and transplant-related complications, were compared between the two groups. Further subgroup analysis was performed based on MFI values. RESULTS: At the time of transplantation, patients in group 1 were younger than those in group 2 (p = .008). The number of fully matched donors within the family (MSD and MFD) was significantly higher in group 1 (p = .049). Additionally, Rh blood group incompatibility was higher in group 2 (p = .03). There was no statistically significant difference in the engraftment days of neutrophils, platelets, and erythrocytes between the two groups. The frequency of poor graft function and graft failure was higher in the group 2, but there was no statistically significant difference. Post-transplant transfusion requirements for platelets and red blood cells were significantly higher in the group 2 (p < .001). Transplant-related complications such as VOD, PRES, and aGvHD were more common in the group 2, but no statistical significance was detected. CONCLUSIONS: Serum PRA in pediatric thalassemia patients may impact the outcomes of HSCT. PRA-positive patients had higher rates of blood product transfusion requirements. Although poor graft function, graft failure, and post-transplant complications were more common in the group 2, statistical significance was not observed. Identifying patients with high PRA levels can assist in optimizing transplant strategies and post-transplant care, leading to improved outcomes for the patients.

cDNA sequencing increases the molecular diagnostic yield in Chediak-Higashi syndrome.

Introduction: Chediak-Higashi syndrome (CHS) is rare autosomal recessive disorder caused by bi-allelic variants in the Lysosomal Trafficking Regulator (LYST) gene. Diagnosis is established by the detection of pathogenic variants in LYST in combination with clinical evidence of disease. Conventional molecular genetic testing of LYST by genomic DNA (gDNA) Sanger sequencing detects the majority of pathogenic variants, but some remain undetected for several individuals clinically diagnosed with CHS. In this study, cDNA Sanger sequencing was pursued as a complementary method to identify variant alleles that are undetected by gDNA Sanger sequencing and to increase molecular diagnostic yield. Methods: Six unrelated individuals with CHS were clinically evaluated and included in this study. gDNA Sanger sequencing and cDNA Sanger sequencing were performed to identify pathogenic LYST variants. Results: Ten novel LYST alleles were identified, including eight nonsense or frameshift variants and two in-frame deletions. Six of these were identified by conventional gDNA Sanger sequencing; cDNA Sanger sequencing was required to identify the remaining variant alleles. Conclusion: By utilizing cDNA sequencing as a complementary technique to identify LYST variants, a complete molecular diagnosis was obtained for all six CHS patients. In this small CHS cohort, the molecular diagnostic yield was increased, and canonical splice site variants identified from gDNA Sanger sequencing were validated by cDNA sequencing. The identification of novel LYST alleles will aid in diagnosing patients and these molecular diagnoses will also lead to genetic counseling, access to services and treatments and clinical trials in the future.

The effect of chemotherapy on symptoms and nutritional status in children with cancer.

PURPOSE: This observational study carried out to determine the incidence of poor nutritional status and symptom burden in children undergoing chemotherapy treatment. METHODS: The research data collected from 187 children between the ages of 7-18 at pediatric hematology-oncology units in Izmir. The data of the study collected with Screening Tool for Risk of impaired Nutritional Status and Growth (STRONGkids), and the Memorial Symptom Assessment Scale (MSAS). RESULTS: Patients reported a mean (SD) of 14.1 (8.1; range, 1-30) symptoms, and 43.9% were underweight. According to the STRONGkids, 62% had a high risk for malnutrition. The incidence of all symptoms increased as the Z-score of the patients worsens. There was a significant positive correlation between mean symptoms and STRONGkids malnutrition risk score, and Z-score (p < .001). CONCLUSION: Most of the patients were at high risk of malnutrition. It observed that chemotherapy treatment led to malnutrition. The patients with high risk for malnutrition according to the STRONGkids and severe malnutrition according to the Z-score experienced more symptoms.

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.

A homozygous duplication of the FGG exon 8-intron 8 junction causes congenital afibrinogenemia. Lessons learned from the study of a large consanguineous Turkish family.

Congenital afibrinogenemia is the most severe congenital fibrinogen disorder, characterized by undetectable fibrinogen in circulation. Causative mutations can be divided into two main classes: null mutations with no protein production at all and missense mutations producing abnormal protein chains that are retained inside the cell. The vast majority of cases are due to single base pair mutations or small insertions or deletions in the coding regions or intron-exon junctions of FGB, FGA and FGG. Only a few large rearrangements have been described, all deletions involving FGA. Here we report the characterization of a 403 bp duplication of the FGG exon 8-intron 8 junction accounting for congenital afibrinogenemia in a large consanguineous family from Turkey. This mutation, which had escaped detection by Sanger sequencing of short polymerase chain reaction (PCR) amplicons of coding sequences and splice sites, was identified by studying multiple alignments of reads obtained from whole exome sequencing of a heterozygous individual followed by PCR amplification and sequencing of a larger portion of FGG. Because the mutation duplicates the donor splice site of intron 8, we predicted that the impact of the mutation would be on FGG transcript splicing. Analysis of mRNA produced by cells transiently transfected with normal or mutant minigene constructs showed that the duplication causes production of several aberrant FGG transcripts generating premature truncating codons.

A novel ITGB2 variant with long survival in patients with leukocyte adhesion defect type-I.

Leukocyte adhesion deficiency is an autosomal recessive primary immunodeficiency that has been divided into three types: LAD1 (beta-2 integrin (CD18) family deficiency/defect), LAD2 (absence of fucosylated carbonhydrate ligands for selectins) and LAD3 (defective activation of all beta integrins). However, recently LAD4 has been described in cystic fibrosis patients, with a defect in integrin activation reported in monocytes. LAD-I is the most common type and prevalence of 1 in 1,000,000 live births. Clinical features of LAD patients are recurrent bacterial and fungal infections, omphalitis with delayed umbilical stump separation, significant leukocytosis especially neutrophilia during infection periods, impaired pus formation, and delayed traumatic or surgical wound healing. Flow cytometry is considered a useful tool for rapid diagnosis of the disease. The study of CD18 and CD11 (a, b, c) expression patterns in peripheral blood leukocytes helps to distinguish different phenotypes of LAD-I. In general, patients with ≥ 2% CD18 expression tend to have a less severe infection and often survive until adulthood, whereas < 2% CD18 expression often results in death in infancy. In this case report, three siblings, 10, 15, and 17 years old, diagnosed with leukocyte adhesion defect type 1 in adolescence age group, are presented.

Ophthalmologic findings and complications before and after hematopoietic stem cell transplantation: single-center study.

PURPOSE: Different and various system complications and late effects may occur after hematopoietic stem cell transplantation (HSCT). It was aimed to obtain information about the frequency of ophthalmologic complications and their relationship with treatment. METHODS: This retrospective study includes 104 children who underwent HSCT between February 2019 and June 2020 at the Pediatric Bone Marrow Transplant Unit. Patients' ages, genders, diagnosis, transplant types, chemotherapy regimens, transplantation details, conditioning regimens, supportive cares, graft versus host disease (GvHD) prophylaxis, infection episodes, and ophthalmologic findings were evaluated. RESULTS: Of the 104 patients included in the study, 38 (36.5%) were female and 66 (63.5%) were male. Average age ± SD was 8.7 ± 4.91. Considering the diagnoses, the majority of the patients were acute lymphoblastic leukemia (46 patients-44%). Myeloablative regimen was used in 93 (89%) of the patients, and reduced intensity conditioning (RIC) was used in 11 patients (10%). While total body irradiation was applied in 16 (15%) patients, one patient was received cranial radiotherapy. Cyclosporine was used in 96 (92%) patients. CMV reactivation was detected in 54 (51%) of the patients. CMV retinitis was not seen. Ocular pathology was detected in 20 (19%) patients before HSCT and in 12 (11%) patients after HSCT. The most common pathology was dry eye. CONCLUSION: Routine ophthalmologic examinations are important in terms of early diagnosis. In addition, GvHD and CMV prophylaxis is important because of reducing the risk of ocular complications after HSCT.

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.

Ifosfamide induced encephalopathy in a child with osteosarcoma.

BACKGROUND: Ifosfamide (IFO) is an alkylating agent used to treat broad range of malignancies. One of the life-threatening toxic effects is reversible neurotoxicity. In this report; we presented a case report of ifosfamide induced encephalopathy (IIE) in a child with osteosarcoma in order to emphize that it is important to continue ifosfamide treatment as well as the importance of this potentially fatal complication. CASE REPORT: Following the 20th week of ifosfamide treatment, the patient's follow-up with the diagnosis of osteosarcoma developed neurological findings. Laboratory analyzes before and after ifosfamide infusion were normal. No pathological findings were seen on MR imaging. Hypoglycemia, electrolyte disturbances, encephalitis, meningitis, metastasis and posterior reversible encephalopathy syndrome (PRES) were not considered. Electroencephalography was found compatible with neuronal hyperexcitability originating from the left hemisphere. With the diagnosis of ifosfamide induced encephalopathy, prophylaxis with methylene blue was received before the next infusion of ifosfamide. Neurological findings were not observed in the patient's follow-up. CONCLUSION: Patients who develop IIE can continue their treatment protocol with methylene blue prophylaxis and supportive therapy.

Mowat-Wilson syndrome: growth charts.

BACKGROUND: Mowat-Wilson syndrome (MWS; OMIM #235730) is a genetic condition caused by heterozygous mutations or deletions of the ZEB2 gene. It is characterized by moderate-severe intellectual disability, epilepsy, Hirschsprung disease and multiple organ malformations of which congenital heart defects and urogenital anomalies are the most frequent ones. To date, a clear description of the physical development of MWS patients does not exist. The aim of this study is to provide up-to-date growth charts specific for infants and children with MWS. Charts for males and females aged from 0 to 16 years were generated using a total of 2865 measurements from 99 MWS patients of different ancestries. All data were collected through extensive collaborations with the Italian MWS association (AIMW) and the MWS Foundation. The GAMLSS package for the R statistical computing software was used to model the growth charts. Height, weight, body mass index (BMI) and head circumference were compared to those from standard international growth charts for healthy children. RESULTS: In newborns, weight and length were distributed as in the general population, while head circumference was slightly smaller, with an average below the 30th centile. Up to the age of 7 years, weight and height distribution was shifted to slightly lower values than in the general population; after that, the difference increased further, with 50% of the affected children below the 5th centile of the general population. BMI distribution was similar to that of non-affected children until the age of 7 years, at which point values in MWS children increased with a less steep slope, particularly in males. Microcephaly was sometimes present at birth, but in most cases it developed gradually during infancy; many children had a small head circumference, between the 3rd and the 10th centile, rather than being truly microcephalic (at least 2 SD below the mean). Most patients were of slender build. CONCLUSIONS: These charts contribute to the understanding of the natural history of MWS and should assist pediatricians and other caregivers in providing optimal care to MWS individuals who show problems related to physical growth. This is the first study on growth in patients with MWS.

Outcomes of Eltrombopag Treatment and Development of Iron Deficiency in Children with Immune Thrombocytopenia in Turkey

Objective: Immune thrombocytopenia (ITP) is a rare autoimmune disease and hematologic disorder characterized by reduced platelet counts that can result in significant symptoms, such as bleeding, bruising, epistaxis, or petechiae. The thrombopoietin receptor agonist eltrombopag (EPAG) is a second-line agent used to treat chronic ITP purpura in adults and children. Materials and Methods: The present retrospective study evaluated the efficacy, safety, and side effects of EPAG treatment in pediatric patients with acute refractory and chronic immune thrombocytopenia, particularly focusing on iron-deficiency anemia. Results: The diagnosis was chronic ITP in 89 patients and acute refractory ITP in 16 patients. The mean age of patients was 9.5±4.5 years (minimum-maximum: 1.2-18 years) at the beginning of EPAG treatment. The overall response rate was 74.3% (n=78). The mean time for platelet count of ≥50x109/L was 11.6±8 weeks (range: 1-34 weeks). The treatment was stopped for 27 patients (25.7%) at an average of 6.8±9 months (range: 1-38 months). The reason for discontinuation was lack of response in 18 patients, nonadherence in 4 patients, and hepatotoxicity in 2 patients. Response to treatment continued for an average of 4 months after cessation of EPAG in 3 patients. Conclusion: Results of the current study imply that EPAG is an effective therapeutic option in pediatric patients with acute refractory and chronic ITP. However, patients must be closely monitored for response and side effects during treatment, and especially for iron deficiency.

Refugee children with beta-thalassemia in Turkey: Overview of demographic, socioeconomic, and medical characteristics.

AIM: Since the beginning of the Syrian civil war, more than 3.5 million Syrians have been under temporary protection status in Turkey. Because beta-thalassemia (BT) is a prevalent disorder in the Mediterranean countries, we decided to estimate the prevalence of and make an overview of the demographic, socioeconomic, medical characteristics, and healthcare problems of refugee children with BT. PATIENTS: Eighteen Turkish Pediatric Hematology Oncology Centers (PHOC) with 318 refugee children from 235 families participated in the study. The mean age of the patients was 8.1 ± 4.8 years (0.5-21 years). The mean time after immigration to Turkey was 2.5 ± 1.5 years (range, 0.1-7 years). Seventy-two (22.6%) of them were born and diagnosed with BT in Turkey. On physical examination, 82 patients (26%) were underweight and 121 patients (38%) were stunted. The appearance of a thalassemic face was reported for 207 patients (65.1%). Hepatomegaly and splenomegaly were reported in 217 (68.2%) and 168 (52.8%) patients, respectively. The median ferritin level was 2508 ng/mL (range, 17-21 000 ng/mL) at the first admission, and 2841 ng/mL (range, 26-12 981 ng/mL) at the last visit after two years of follow-up in a PHOC (P > 0.05). The most frequently encountered mutation was IVSI-110 (G>A) (31%). Before immigration, only 177 patients (55.6%) reported the use of chelators; after immigration it increased to 268 (84.3%). CONCLUSION: Difficulties in communication, finding a competent translator capable in medical terminology, nonregular use of medications, and insensitivity to prenatal diagnosis were preliminary problems. The current extent of migration poses emerging socioeconomic and humanitarian challenges for refugee patients with BT.

A Case of Allergic Broncopulmonary Aspergillosis Associated With Hematopoietic Stem Cell Transplantation Due to Chronic Granulomatous Disease.

Allergic bronchopulmonary aspergillosis is an immunologic pulmonary disorder caused by hypersensitivity to Aspergillus fumigatus. This disorder is most commonly seen in patients with poorly controlled asthma and cystic fibrosis. It is rarely reported in chronic granulomatous disease patients; however, there are no cases reported with hematopoietic stem cell transplantation in the English literature. Herein, we report a patient with chronic granulomatous disease who had hematopoietic stem cell transplantation and subsequently developed allergic bronchopulmonary aspergillosis.

Phenotype and genotype of 87 patients with Mowat-Wilson syndrome and recommendations for care.

PURPOSE: Mowat-Wilson syndrome (MWS) is a rare intellectual disability/multiple congenital anomalies syndrome caused by heterozygous mutation of the ZEB2 gene. It is generally underestimated because its rarity and phenotypic variability sometimes make it difficult to recognize. Here, we aimed to better delineate the phenotype, natural history, and genotype-phenotype correlations of MWS. METHODS: In a collaborative study, we analyzed clinical data for 87 patients with molecularly confirmed diagnosis. We described the prevalence of all clinical aspects, including attainment of neurodevelopmental milestones, and compared the data with the various types of underlying ZEB2 pathogenic variations. RESULTS: All anthropometric, somatic, and behavioral features reported here outline a variable but highly consistent phenotype. By presenting the most comprehensive evaluation of MWS to date, we define its clinical evolution occurring with age and derive suggestions for patient management. Furthermore, we observe that its severity correlates with the kind of ZEB2 variation involved, ranging from ZEB2 locus deletions, associated with severe phenotypes, to rare nonmissense intragenic mutations predicted to preserve some ZEB2 protein functionality, accompanying milder clinical presentations. CONCLUSION: Knowledge of the phenotypic spectrum of MWS and its correlation with the genotype will improve its detection rate and the prediction of its features, thus improving patient care.

Neuroimaging findings in Mowat-Wilson syndrome: a study of 54 patients.

PURPOSE: Mowat-Wilson syndrome (MWS) is a genetic disease characterized by distinctive facial features, moderate to severe intellectual disability, and congenital malformations, including Hirschsprung disease, genital and eye anomalies, and congenital heart defects, caused by haploinsufficiency of the ZEB2 gene. To date, no characteristic pattern of brain dysmorphology in MWS has been defined. METHODS: Through brain magnetic resonance imaging (MRI) analysis, we delineated a neuroimaging phenotype in 54 MWS patients with a proven ZEB2 defect, compared it with the features identified in a thorough review of published cases, and evaluated genotype-phenotype correlations. RESULTS: Ninety-six percent of patients had abnormal MRI results. The most common features were anomalies of corpus callosum (79.6% of cases), hippocampal abnormalities (77.8%), enlargement of cerebral ventricles (68.5%), and white matter abnormalities (reduction of thickness 40.7%, localized signal alterations 22.2%). Other consistent findings were large basal ganglia, cortical, and cerebellar malformations. Most features were underrepresented in the literature. We also found ZEB2 variations leading to synthesis of a defective protein to be favorable for psychomotor development and some epilepsy features but also associated with corpus callosum agenesis. CONCLUSION: This study delineated the spectrum of brain anomalies in MWS and provided new insights into the role of ZEB2 in neurodevelopment.Genet Med advance online publication 10 November 2016.