Search

Introduction: Beta-thalassemia is a group of inherited hemolytic anemias and one of the most common genetic disorders in Thailand. The clinical spectrum of beta-thalassemia disease ranges from mild to severe clinical symptoms including mild beta-thalassemia intermedia (TI) and severe beta-thalassemia major (TM). Objective: This study aimed to determine the correlation between beta-globin gene (HBB) mutations and their phenotypic manifestations by evaluating patients' clinical characteristics, transfusion requirements, growth and hematologic parameters, and hemoglobin typing among pediatric patients treated at Phramongkutklao Hospital. Materials and methods: Seventy beta-thalassemia patients, including 63 with betathalassemia/hemoglobin E (HbE) and 7 with either homozygous or compound heterozygous beta-thalassemia, were enrolled in this study. Their clinical presentation, growth parameters and laboratory findings were reviewed and analyzed. The mean follow-up time was 10.52±5.62 years. Mutation analysis in each individual was performed using multiplex amplification refractory mutation system (M-ARMS), direct DNA sequencing of beta-globin gene and gap PCR for 3.4 kb deletion detection. Results: All 7 homozygous and compound heterozygous beta-thalassemia patients were classified in TM. Among 63 patients with beta-thalassemia/HbE, 58 were classified in TM and 4 were classified in TI. Mean age at diagnosis was 0.8±0.49 years for homozygous or compound heterozygous beta-thalassemia and 3.43±3.5 years for beta-thalassemia/HbE. The most common HBB mutation was HBB:c.126_129delCTTT [codon 41/42 (-TCTT)] found in 34 alleles (48.6%). The height for age was also lower in homozygous beta-thalassemia patients (<3rd percentile) compared to compound heterozygous beta-thalassemia patients (25-50th percentile). Conclusion: This study revealed a genotype-phenotype correlation of the most prevalent betathalassemia in Thai children using diagnostic capacity in genotypic analysis of HBB mutation. Our findings can provide a better prediction of clinical manifestation and severity by early identification of the type of the HBB mutations. [ABSTRACT FROM AUTHOR]

Background: Alpha-thalassemia is a common genetic disorder in Thailand and is caused by either deletion or non-deletional mutation of one or both α-globin genes. Inactivation of three α-globin genes causes Hb H disease and interaction of Hb H disease with heterozygous Hb E results in AEBart’s disease. Objective: The present study aimed to characterize the genotype of α-globin gene in 81 pediatric patients with Hb H and AEBart’s diseases in Phramongkutklao Hospital, a tertiary care center for thalassemic patients in central Thailand. Material and Method: Eighty one unrelated pediatric patients including 60 patients with Hb H disease and 21 patients with AEBart’s disease were enrolled in our study. Mutation analysis was performed by multiplex gap-PCR, multiplex-ARMS and direct DNA sequencing of both HBA1 and HBA2 genes, respectively. Results: A total of 81 pediatric patients with Hb H and AEBart’s diseases who mainly lived in central Thailand were included in the present study. Eight different α-thalassemia mutations interacting to produce seven genotypes of α-globin gene in both Hb H and AEBart’s diseases were identified. The number of patients in the non-deletional form was higher than in the deletional form for both Hb H (51.6% VS 48.4%) and AEBart’s diseases (52.4% VS 47.6%). The SEA deletion (--SEA) was the most common (98.8%) α-thalassemia 1 mutation. While 3.7-kb deletion (-α3.7) was the most common (90%) α-thalassemia 2 deletion, Hb CS was the most common (90%) non-deletional a-thalassemia 2. Uncommon non-deletional α-thalassemia 2 mutation identified in our study were Hb QS, Hb PS and initiation codon mutation, respectively. Conclusion: All of the α-thalassemia mutation in our pediatric patients with Hb H and AEBart’s diseases have been characterized by the combination of molecular techniques including multiplex gap-PCR, multiplex-ARMS and DNA sequencing of HBA1 and HBA2 genes. [ABSTRACT FROM AUTHOR]

Killer cell Ig-like receptors (KIRs) on NK cells have been linked to a wide spectrum of health conditions such as chronic infections, autoimmune diseases, pregnancy complications, cancers, and transplant failures. A small subset of effector memory T cells also expresses KIRs. In this study, we use modern analytic tools including genome-wide and multiplex molecular, phenotypic, and functional assays to characterize the KIR+ T cells in human blood. We find that KIR+ T cells primarily reside in the CD56+ T population that is distinctively DNAM-1high with a genome-wide quiescent transcriptome, short telomere, and limited TCR excision circles. During CMV reactivation in bone marrow transplant recipients, KIR+CD56+ T cells rapidly expanded in real-time but not KIR+CD56- T cells or KIR+ NK cells. In CMV+ asymptomatic donors, as much as 50% of CD56+ T cells are KIR+, and most are distinguishably KIR2DL2/3+NKG2C+CD57+. Functionally, the KIR+CD56+ T cell subset lyses cancer cells and CMVpp65-pulsed target cells in a dual KIR-dependent and TCR-dependent manner. Analysis of metabolic transcriptome confirms the immunological memory status of KIR+CD56+ T cells in contrast to KIR-CD56+ T cells that are more active in energy metabolism and effector differentiation. KIR-CD56+ T cells have >25-fold higher level of expression of RORC than the KIR+ counterpart and are a previously unknown producer of IL-13 rather than IL-17 in multiplex cytokine arrays. Our data provide fundamental insights into KIR+ T cells biologically and clinically. [ABSTRACT FROM AUTHOR]

Despite the use of intensive contemporary multimodal therapy, the overall survival of patients with high-risk neuroblastoma is still less than 50%. Therefore, immunotherapy without cross-resistance and overlapping toxicity has been proposed. In this study, we report the development of a novel strategy to specifically activate and expand human CD56+ (NCAM1) natural killer (NK) immune cells from normal donors and patients with neuroblastoma. Enriched CD56+ cells from peripheral blood were mixed with CD56- fraction at 1:1 ratio and cultured in the presence of OKT3, interleukin (IL)-2, and -15 for five days and then without OKT3 for 16 more days. The final products contained more than 90% CD56+ cells and could kill neuroblastoma cells effectively that were originally highly resistant to nonprocessed NK cells. Mechanistically, cytolysis of neuroblastoma was mediated through natural cytotoxicity receptor (NCR), DNAX accessory molecule-1 (DNAM-1; CD226), perforin, and granzyme B. Successful clinical scale-up in a good manufacturing practices (GMP)-compliant bioreactor yielded effector cells that in a neuroblastoma xenograft model slowed tumor growth and extended survival without GVHD. Investigation of CD56+ cells from patients with neuroblastoma revealed a similar postactivation phenotype and lytic activity. Our findings establish a novel and clinically expedient strategy to generate allogeneic or autologous CD56+ cells that are highly cytotoxic against neuroblastoma with minimal risk of GVHD. [ABSTRACT FROM AUTHOR]

Background aims. Peripheral blood stem cells (PBSC) are increasingly used as an alternative to bone marrow in autologous transplantations. In adult patients, the peripheral blood CD34 ++ cell count is a good predictor of CD34 ++ cell yield in apheresis. However, the determinants of stem cell yield in the pediatric population have not been well established. Methods. We retrospectively studied 396 apheresis procedures in 301 pediatric patients. Receiver operating characteristic (ROC) curves based on pre-apheresis peripheral blood CD34 ++ cell counts were generated to facilitate prediction of the optimal timing of PBSC collection. The associations between CD34 ++ cell yield and age and mobilization regimen were analyzed. Results. Significant differences in CD34 ++ cell yield among different age groups were observed. Furthermore, higher CD34 ++ cell yields were obtained in patients receiving chemotherapy as part of the mobilization regimen than those without chemotherapy. A correlation was noted between the CD34 ++ cell yield and blood surrogate markers, including white blood cell count, absolute neutrophil count and pre-apheresis peripheral blood CD34 ++ cell count. Cut-off values of > 35 CD34 ++ cells/μL in patients < 15 years old and > 45 CD34 ++ cells/μL in patients ≥ 15 years old were strong predictors of an adequate PBSC collection in one apheresis session. For clinical use, ROC curves and tables were generated to assist advance planning for PBSC collection. Conclusions. The pre-apheresis peripheral blood CD34 ++ cell count is most useful in predicting PBSC yield. Our new cut-off values have better operating characteristics for children than the conventional value of 20 CD34 ++ cells/μL used for adults. [ABSTRACT FROM AUTHOR]

Objectives: This study aimed to enhance the learning experience among medical students by empowering them to co-create learning tools and classroom activities., Methods: A cross-sectional study was conducted with 10 participants from Year 2 of the new curriculum volunteering to participate in this study. Five were selected based on their diversities and empowered to design learning tools and class activities. Student satisfaction was presented as mean scores. A comparison of self-confidence scores in subjects learned before and after the class was analyzed using the paired t-test. Comparisons of multiple-choice question (MCQ) scores before and after the class between Years 2 (n = 96) and Year 3 of the previous curriculum attending inclass teaching (n = 98) were analyzed using the independent sample t-test., Results: A high level of satisfaction (M=87.5, SD=15.7%) and significant improvements in student self-confidence in subjects learned between before (M=46.4, SD=20.8%) and after (M=82.7, SD=16.9%) the class were noted (t (223) = -23.73, p<.001). Additionally, Year 2 students achieved significantly higher MCQ scores after the class (M=85.6, SD=19.0%) compared with the scores from Year 3 (M=77.3, SD=23.6%) (t (190) = 3.32, p<.001)., Conclusions: Empowering medical students to co-create learning tools and class activities could positively enhance their learning experience. The result of this study addressed the importance of student empowerment with well-designed student-centered learning strategies based on their learning environment. Additional qualitative research is required to better understanding the "why" and "how" behind the findings of this study.

Background: Hemophagocytic lymphohistiocytosis (HLH) is a rare, life-threatening condition caused by genetic mutation or various triggers disturbing the immune system., Methods: A multicenter retrospective study of pediatric patients with HLH receiving a diagnosis between January 2005 and December 2019 from three pediatric oncology centers was conducted to explore the clinical characteristics and determine prognostic factors associated with outcomes among Thai children., Results: In all, 78 patients with HLH with a median age at diagnosis of 3.17 (range, .08-17.83) years were enrolled. The male to female ratio was 1.2:1. The most common type of HLH was infection-associated hemophagocytic syndrome (IAHS) (n = 59, 75%) of which Epstein-Barr virus was the most common pathogen. Thrombocytopenia, hyperbilirubinemia, and treatment response at weeks 2 and 8 after initiating treatment were associated with mortality. Platelet count <50,000 cells/mm 3 was the only independent prognostic factor to define survival outcome (p-value .035). Two-year overall survival rate was 71.3% (95% confidence interval, 59.2%-80.3%). Survival rates between IAHS, malignant associated HLH, macrophage activation syndrome, and unspecific HLH did not significantly differ (p-value .571)., Conclusion: IAHS was the most common cause among pediatric HLH in Thailand. The outcomes of Thai children with HLH were comparable to those of developed countries. Platelet count <50,000 cells/mm 3 was the only independent prognostic factor to define survival outcome., (© 2022 John Wiley & Sons Australia, Ltd.)

Introduction: Beta-thalassemia is a group of inherited hemolytic anemias and one of the most common genetic disorders in Thailand. The clinical spectrum of beta-thalassemia disease ranges from mild to severe clinical symptoms including mild beta-thalassemia intermedia (TI) and severe beta-thalassemia major (TM)., Objective: This study aimed to determine the correlation between beta-globin gene ( HBB ) mutations and their phenotypic manifestations by evaluating patients' clinical characteristics, transfusion requirements, growth and hematologic parameters, and hemoglobin typing among pediatric patients treated at Phramongkutklao Hospital., Materials and Methods: Seventy beta-thalassemia patients, including 63 with beta-thalassemia/hemoglobin E (HbE) and 7 with either homozygous or compound heterozygous beta-thalassemia, were enrolled in this study. Their clinical presentation, growth parameters and laboratory findings were reviewed and analyzed. The mean follow-up time was 10.52±5.62 years. Mutation analysis in each individual was performed using multiplex amplification refractory mutation system (M-ARMS), direct DNA sequencing of beta-globin gene and gap PCR for 3.4 kb deletion detection., Results: All 7 homozygous and compound heterozygous beta-thalassemia patients were classified in TM. Among 63 patients with beta-thalassemia/HbE, 58 were classified in TM and 4 were classified in TI. Mean age at diagnosis was 0.8±0.49 years for homozygous or compound heterozygous beta-thalassemia and 3.43±3.5 years for beta-thalassemia/HbE. The most common HBB mutation was HBB:c.126&#95;129delCTTT [codon 41/42 (-TCTT)] found in 34 alleles (48.6%). The height for age was also lower in homozygous beta-thalassemia patients (<3rd percentile) compared to compound heterozygous beta-thalassemia patients (25-50th percentile)., Conclusion: This study revealed a genotype-phenotype correlation of the most prevalent beta-thalassemia in Thai children using diagnostic capacity in genotypic analysis of HBB mutation. Our findings can provide a better prediction of clinical manifestation and severity by early identification of the type of the HBB mutations., Competing Interests: Disclosure The authors report no conflicts of interest in this work.

More than 80% of acute lymphoblastic leukemia (ALL) in pediatric population is curable by using combinations of chemotherapy. However, 20% of the cases still suffer from disease relapse. The most common site of relapse is bone marrow. Relapse of childhood ALL involving the eyeball is rare. However, it occurs in 2.2% of relapsing children. The authors described a 10-year-old Thai boy with underlying ALL on therapy, presented with a one-month history of progressive visual loss of his right eye. The clinical and imaging studies strongly suggested the diagnosis of isolated ocular relapse. In this report, the authors presented the findings from successfully specific treatment consisting of systemic chemotherapy and radiation therapy on the affected eye. From other studies, the outcome was more favorable in cases of ocular relapse off therapy. In our study, one case of isolated ocular relapse ALL was reported.

Background: Children often require relief of pain and anxiety when undergoing painful procedures., Objective: To determine the differences by comparing fentanyl and ketamine used in cancer-diagnosed children undergoing painful procedures., Material and Method: A randomized, double-blinded, crossover trial was conducted with 55 children undergoing painful procedures (intrathecal chemotherapy and/or bone marrow aspiration/biopsy). Patients were randomly assigned in a double-blinded fashion to receive either intravenous fentanyl or ketamine at 1 mcg/kg/dose and 1 mg/kg/dose, respectively. The result in effectiveness of the drug was measured using three parameters, 1) satisfaction score ranging from 0 to 10, 2) perception of procedural pain using FLACC scale, Wong-Baker FACES Pain Rating Scale and Visual Analog Scale, and 3) the frequency of vomiting nausea score., Results: The satisfaction amongpatients receiving fentanyl was significantly greater than ketamine (p = 0.007). In addition, both painful and nausea/vomiting were significantly decreased in the patients receiving fentanyl (p = 0.002 and p < 0.001, respectively). No serious complications were observed, Conclusion: This study demonstrated that intravenous fentanyl generated a superior clinical effect in satisfaction, decreased pain and nausea/vomiting, and showed no significant side-effects over ketamine. Fentanyl may also be recommended as a reasonable option before undergoing oncology procedures in children with cancer.

Background: Leukemia is the most common malignancy in children. Multiple prognostic factors have been used in order to assist the clinician to decide appropriate risk-adjusted treatment for each patient; the current clinical outcomes of those patients have been significantly improved over the past decades., Objective: The purpose of this study was to examine survival outcome in children who were diagnosed with acute leukemia and treated in the Department of Pediatrics, Phramongkutklao Hospital during January 1, 2000 and July 31, 2013., Material and Method: The authors retrospectively reviewed the patients who were diagnosed with acute leukemia and treated at Phramongkutklao Hospital. Their clinical data were collected and analyzed based on clinicalfeatures inchluding age, initial WBC count at diagnosis, sex, immnunophenotype and cytogenetic abnormalities., Results: Total 152 patients with acute leukemia, 123 patients were diagnosed with acute lymnphoblastic leukemia (ALL) and 29 patients were diagnosed with acute myeloid leukemia (AML). The 5-year survival rates of ALL and AML patients were 72.63% and 30.30%, respectively. In addition, we found a correlation between the ALL patients' clinical outcomes and several prognostic factors including initial white blood cell count, CNS status at diagnosis and ploidy. However, there was no correlation between those factors and clinical outcomes in AML patients., Conclusion: Our treatment outcomes on patients with acute leukemia were similar to the reports from other countries. The several prognostic factors especially initial WBC at diagnosis can assist the clinician to select appropriate treatment option for each patient.

Background: The pain and its complication during sedation with ketamine remain a significant problem for children with hematologic malignancy., Objective: The purpose of the present study was to evaluate further the parental satisfaction for procedural sedation and analgesia during pediatric hematology/oncology procedures perfonned by pediatrician in the Department of Pediatrics, Phramongkutklao Hospital., Material and Method: The authors prospectively evaluated our experience using intravenous ketamine 1 mg/kg for oncology patients undergoing procedures at Department ofPediatrics, Phramongkutklao Hospital. The procedure was assessed by way ofaphysician-completed form and by evaluation of questionnaires given to parents to estimate levels of pain by using a 0 to 10 mm visual analog scale (VAS) at 2 hours after procedures and results in any adverse events with respect to age, gende, procedures performed, ketamine dosage and recovery time., Results: Total of46 children aged 6 months to 15 years with 46procedures were observed at pediatric unit post-procedure. The indicationsfor procedural sedation and analgesia included lumbar puncture and intrathecal chemotherapy (50%), bone marrow aspiration or biopsy (21.7%), and both plrocedures (28.3%). The median VAS scale during oncology procedures was 3, which were expressed by all the parents/guardians of the children treated. Adverse effects were observed in all children including nausea (30.4%), hypersalivation (26.1%), vomiting (21.7%), hallucinlation (4.2%). No child required admission to hospital and there were no serious complications., Conclusion: hntravenous ketamine 1 mg/kg is effective for invasive procedures in children with malignancy. The use of intravenous ketamine may produce psychedelic effects in children. These adverse effects may alter the child's comfort and parental satisfaction especially in the young children.

Background: Shwachman-Diamond syndrome is an inherited multisystem disorder characterized by bone marrow and pancreatic dysfunction as well as metaphyseal dysostosis. Ninety percent of the patients have mutations in the Shwachman-Bodian-Diamond syndrome gene (SBDS). The relationship between SBDS and cell survival is unknown. In this study we investigated whether deficiency of the SBDS protein can cause increased apoptosis and, if so, what pathways are involved in this process., Design and Methods: To determine whether accelerated apoptosis of Shwachman-Diamond syndrome cells is caused by a deficiency in SBDS we generated two SBDS-knockdown cell clones. We then evaluated, Fas expression and levels of the intracellular proteins, BAX, BCL-2 and BCL-X(L) and determined the effects of apoptosis inhibitors. Using oligonucteotide-microarrays we also analyzed apoptosis-related gene expression in Shwachman-Diamond syndrome marrow cells., Results: We found that knocking down SBDS by short interfering hairpin RNA in HeLa cells resulted in a prominent increase in cell death. The mechanism for the accelerated apoptosis was related to marked hypersensitivity to Fas stimulation, and increased Fas expression. In contrast, there was no increase in the expression ratio of the pro-apoptotic factor, BAX, to the pro-survival factors, BCL2 and BCL-X(L) in the SBDS-knockdown cells and in the patients' marrow cells. Furthermore, inhibition of Fas and caspase 8, but not caspase 9, significantly improved the defective cell growth phenotype., Conclusions: Our work provides new data about the pro-survival properties of SBDS, whose inhibition results in accelerated apoptosis through the Fas pathway.