Molecular characteristics of hereditary red blood cell membrane disorders in Thailand: a multi-center registry.

Red blood cell (RBC) membrane disorders represent a significant category of hereditary hemolytic anemia; however, information from Southeast Asia is limited. We established a national registry aiming to characterize RBC membrane disorders and their molecular features in Thailand. A total of 100 patients (99 kindreds) diagnosed with RBC membrane disorders between 2011 and 2020 from seven university hospitals were enrolled. The most prevalent disorders observed were hereditary elliptocytosis (HE; n=33), hereditary pyropoikilocytosis (HPP; n=28), hereditary spherocytosis (HS; n=19), Southeast Asian ovalocytosis (SAO; n=10 of 9 kindreds), and two cases of homozygous SAO. The remaining cases were grouped as unclassified membrane disorder. Seventy-six patients (76%) were molecularly confirmed by PCR, direct DNA sequencing, or hi-throughput sequencing. The primary causative gene for HE and HPP was SPTB, accounting for 28 out of 29 studied alleles for HE and 56 of 56 studied alleles for HPP. In the case of HS, dominant sporadic mutations in the ANK1 gene (n=4) and SPTB gene (n=3) were identified as the underlying cause. Notably, the four most common variants causing HE and HPP were SPTB Providence (c.6055 T>C), SPTB Buffalo (c.6074 T>G), SPTB Chiang Mai (c.6224 A>G), and SPTB c.6171__82delins TGCCCAGCT. These recurrent SPTB mutations accounted for 79 out of 84 mutated SPTB alleles (94%). In summary, HE and hereditary HPP associated with recurrent SPTB mutations are the predominant types of RBC membrane disorders observed in Thailand. These findings have significant implications for the clinical management and future research of RBC membrane disorders in the region.

Survival outcomes of myeloid leukemia associated with Down syndrome and de novo acute myeloid leukemia in children: Experience from a single tertiary center in Thailand.

Few studies have reported the survival outcomes of myeloid leukemia associated with Down syndrome (DS) in resource-limited countries. This study aimed to compare characteristics and survival outcomes of children with acute myeloid leukemia (AML) between those with and without DS in Thailand. The medical records of AML patients aged 0-15 years treated in a major tertiary center in Southern Thailand between October 1978 and December 2019 were reviewed retrospectively. The overall (OS) and event-free survivals (EFS) rates were calculated using the Kaplan-Meier method. A total of 362 AML patients were included, of which 41 (11.3%) had DS. The mean age at diagnosis of the DS patients was 2.5 ± 1.9 years and most of them (90.2%) were under the age of five. The DS patients had lower initial white blood cell counts and peripheral blasts compared to the non-DS patients. The AML-M7 subtype was more common in the DS than in the non-DS patients (80.5% vs. 9.1%, p < 0.01, respectively). The 5-year OS and EFS rates of the DS patients were lower compared to the non-DS patients (12.9% vs. 20.5%, p = 0.05 and 13.7% vs. 18.4%, p = 0.03, respectively). DS patients had a significantly higher rate of early and treatment-related deaths compared to non-DS patients (30.3% vs. 13.5%, p < 0.01 and 39.4% vs. 19.5%, p = 0.02, respectively). Over the study period, there were a decrease in early death rate and an increase in survival rates of DS patients, which suggests that chemotherapy regimens and supportive care have improved over time.

Prevalence and risk factors of disseminated intravascular coagulation in childhood acute lymphoblastic leukemia.

BACKGROUND: Few studies have examined disseminated intravascular coagulation (DIC) in childhood acute lymphoblastic leukemia (ALL). Our aims were to evaluate the prevalence, risk factors and outcomes of DIC at ALL presentation and during induction chemotherapy. METHODS: The medical records of ALL patients aged <15 years were retrospectively reviewed. Logistic regression analysis was used to identify risk factors. The Kaplan-Meier method was used to depict survival. RESULTS: Of the 312 patients, 48 (15.4%) and 76 (24.4%) had DIC at presentation and during induction chemotherapy, respectively. Risk factors for DIC at presentation (OR and 95% CI) were antibiotics prior to admission 2.34 (1.17-4.89), white blood cell count ≥100 × 109/L 2.39 (1.04-5.72), platelets <100 × 109/L 5.44 (1.84-23.4) and high National Cancer Institute (NCI) risk 2.68 (1.08-6.62). Risk factors for DIC during induction chemotherapy were antibiotics prior to admission 1.86 (1.07-3.27), high peripheral blasts 1.01 (1.00-1.02) and transaminitis 2.02 (1.18-3.48). Five-year overall survival of patients who had DIC was significantly lower than those who did not (45.0% vs. 74.1%, p <0.001). CONCLUSION: Antibiotics prior to admission, hyperleukocytosis, thrombocytopenia and high NCI risk were risk factors of DIC at presentation. Antibiotics prior to admission, high peripheral blasts and transaminitis were risk factors of DIC during induction chemotherapy. IMPACT: There are only two studies, both published before 2000, evaluating risk factors of DIC in pediatric ALL patients without reporting outcomes. DIC was associated with lower remission and survival rates in pediatric ALL patients. We identified the risk factors of DIC at presentation as antibiotics prior to admission, hyperleukocytosis, thrombocytopenia and high NCI risk. The risk factors of DIC during induction chemotherapy were antibiotics prior to admission, high peripheral blasts and aspartate transaminitis. Pediatric ALL patients who have the aforementioned risk factors should be closely monitored for DIC secondary to infection, and early treatment with appropriate antimicrobial agents is recommended.

Thalassemia-related complications in pediatric, adolescent, and young adult patients with transfusion-dependent thalassemia: A multicenter study in Thailand.

INTRODUCTION: Management of transfusion-dependent thalassemia (TDT) can be challenging due to numerous potential disease-related complications and comorbidities in particular age groups. The objective of this study was to report thalassemia-related complications and risk factors in pediatric, adolescent, and young adult patients with TDT. METHODS: A multicenter web-based registry was conducted in patients with TDT aged 25 years and younger from eight university hospitals covering all parts of Thailand. Factors significantly associated with each complication were analyzed by logistic regression methods. RESULTS: Of 605 patients, 267 thalassemia-related complications were reported from 231 pediatric, adolescent, and young adult patients with TDT patients (38.2%). The most common complications were infections, followed by cholelithiasis and growth failure. Splenectomy and elevated pre-transfusion hemoglobin were statistically significant risk factors for infections (adjusted odds ratio [AOR] = 2.3, 95% confidence interval [CI]: 1.2-4.5, p-value = .01 and AOR = 1.5, 95% CI: 1.2-1.7, p-value < .005, respectively). There were two statistically significant risk factors conferred endocrinopathies, including older age (AOR = 1.06, 95% CI: 1.01-1.1, p-value = .01) and being male (AOR = 2.4, 95% CI: 1.4-4.0, p-value = .002). CONCLUSION: Nearly 40% of the patients in this cohort had thalassemia-related complications. Periodic surveillance and optimal care for respective complications may minimize comorbidities in pediatric, adolescent, and young adult patients with TDT.

Transient abnormal myelopoiesis in Down syndrome: Experience of long term follow up from a single tertiary center in Thailand.

Transient abnormal myelopoiesis (TAM) is a unique disease occurring in Down syndrome (DS) infants from which most patients have spontaneous remission. This study aimed to evaluate the incidence and outcomes of TAM in a tertiary center in Thailand. We reviewed the records of 997 DS patients diagnosed between June 1993 and October 2019. From the 997 DS patients, 32 had been diagnosed with TAM. The incidence of TAM was 3.2% and an overall survival rate of 87.5%. A total of 2/28 who survived (7.1%) subsequently developed AML-DS at the ages of 2.1 and 4.5 years, respectively. The risk factors related with death included maternal multiparity, sepsis, skin bleeding, subcutaneous nodules, high WBC count, low hemoglobin, and elevated AST level.Abbreviations.

Treatment outcomes in childhood acute lymphoblastic leukemia: 40-year experience from a single tertiary center in Thailand.

Studies on the long-term treatment outcomes of childhood acute lymphoblastic leukemia (ALL) in resource-limited countries are scarce. The purpose of this study was to assess the evolution of survival outcomes of pediatric ALL in a tertiary care center in Thailand over a 40-year period. We retrospectively reviewed the medical records of pediatric patients who were diagnosed with ALL and treated at our center between June 1979 and December 2019. We classified the patients into 4 study periods depending on the therapy protocol used to treat the patients (period 1: 1979-1986, period 2: 1987-2005, period 3: 2006-2013, and period 4: 2014-2019). The Kaplan-Meier method was used to determine overall and event-free survival (EFS) for each group. The log-rank test was used to identify statistical differences. Over the study period, 726 patients with ALL were identified, 428 boys (59%) and 298 girls (41%), with a median age at diagnosis of 4.7 years (range: 0.2-15 years). The study periods 1, 2, 3, and 4 had 5-year EFS rates of 27.6%, 41.6%, 55.9%, and 66.4%, and 5-year overall survival (OS) rates of 32.8%, 47.8%, 61.5%, and 69.3%, respectively. From periods 1 to 4, both the EFS and OS rates increased significantly (p <. 0001). Age, study period, and white blood cell (WBC) count were all significant prognostic indicators for survival outcomes. The OS of patients with ALL treated in our center improved significantly over time from 32.8% in period 1 to 69.3% in period 4.

Red blood cell alloimmunization and other transfusion-related complications in patients with transfusion-dependent thalassemia: A multi-center study in Thailand.

BACKGROUND: Thalassemia is a common genetic disease in Southeast Asia. Red blood cell (RBC) transfusion is an essential treatment for severe forms of thalassemia. We performed a study to demonstrate RBC alloimmunization and other transfusion-related complications in patients with transfusion-dependent thalassemia (TDT). STUDY DESIGN AND METHODS: A multi-center web-based registry of TDT was conducted in eight medical centers across Thailand. Thalassemia information, transfusion therapy, and transfusion-related complications were collected. Factors associated with each complication were demonstrated using the logistic regression analysis. RESULTS: Of 1000 patients recruited for the study, 449 were males (44.9%). The mean age was 23.9 ± 15.4 years. The majority of patients, 738 (73.8%) had hemoglobin E/beta-thalassemia. In the study, 421 transfusion-related complications were reported from 357 patients (35.7%). Alloimmunization was the most common complication which was found in 156 patients (15.6%) with 284 positive antibody tests. The most frequent antibodies against RBC were anti-E (80/284, 28.2%) followed by anti-Mia (45/284, 15.8%) and anti-c (32/284, 11.3%). Age ≥3 years at initial blood transfusion, splenomegaly, higher frequencies, and volumes of transfusion were significant factors associated with alloimmunization. None of the patients had to terminate blood transfusion due to multiple alloantibodies. Other commonly seen complications were allergic reactions (130, 13.0%), autoimmune hemolytic anemia (70, 7.0%) and febrile non-hemolytic transfusion reaction (54, 5.4%). CONCLUSIONS: Transfusion-related complications, especially alloimmunization, were common among Thai patients with TDT. Extended RBC antigen-matching for the Rh system and Mia should be implemented to prevent the development of alloantibodies in multi-transfused patients.

Predictive factors for adverse outcome of advanced-stage childhood lymphoblastic lymphoma: a single tertiary center retrospective study in Thailand.

Childhood lymphoblastic lymphoma (LL) is a highly aggressive neoplasm which has achieved favorable survival outcomes in many developed countries. However, few studies have reported treatment outcomes of childhood LL in resource-limited counties, nor has a prognostic scoring system been developed. The objectives of this study were to evaluate survival outcomes and identify prognostic factors associated with inferior outcomes of childhood LL in a referral center in March 1985 and April 2017 were retrospectively reviewed. Seventy-five advanced-stage LL patients were included, 47 (62.7%) of whom had stage IV at initial diagnosis. The 5-year DFS and OS rates were 44.6% and 44.7%, respectively. There were 3 significant prognostic factors associated with worse outcomes: presence of B symptoms, low albumin level < 3.5 g/dL and serum LDH level > 500 IU/L. From these three factors, we assigned a score of 1 for each and total scores of 0, 1, 2, and 3 could predict 5-year OS rates of 92.3%, 50.9%, 24.7% and 0%, respectively (p < 0.05). The survival of children in this study was lower than in other studies of advanced-stage childhood LL. We identified 3 adverse prognostic factors and developed a prognostic model for clinical use in advanced-stage childhood LL.

An evaluation of the association between radiological parameters and survival outcomes in pediatric patients with hepatoblastoma.

BACKGROUND: We evaluated the survival outcomes following hepatic resection as a treatment modality in pediatric patients with hepatoblastoma at a single institution, and to identify radiological parameters associated with poorer survival outcomes. METHODS: This was a retrospective cohort study. Medical records were reviewed, pertaining to pediatric patients diagnosed with hepatoblastoma who underwent surgical resection at a university hospital in Thailand between 2004 and 2021. Radiological parameters, clinical factors, and pathological data were also collected. Survival analysis was performed, and prognostic factors were identified using logistic regression analysis. RESULTS: Forty-two suitable patients were identified. Three cases with incomplete data were excluded, resulting in 39 cases being analyzed. Except for two, all patients received preoperative chemotherapy following the Thai Pediatric Oncology Group regimen. The two- and five-year overall survival rates were 78.0% and 70.9%, respectively. Upon analysis, the radiological parameters associated with poorer survival were poor response to neoadjuvant chemotherapy, presence of metastasis, post-chemotherapy tumor diameter, Post treatment extent of disease (POSTTEXT) Stage IV disease, presence of portal vein involvement, and presence of residual disease; poor neoadjuvant-response, portal vein involvement, and metastasis were independently associated with worse outcomes. In patients with non-metastatic hepatoblastoma who had at least a 25% reduction in size following neoadjuvant chemotherapy, the 5-year survival rate was 90.9% (95% CI 50.8-98.6%). CONCLUSIONS: Although preoperative evaluation of the tumor extent staging did not significantly affect survival, portal vein involvement as per POSTTEXT staging, stable or increasing tumor size, and metastasis following neoadjuvant chemotherapy were associated with poor overall survival. LEVEL OF EVIDENCE: IIB.

Successful Treatment of Gaucher Disease With Matched Sibling Hematopoietic Stem Cell Transplantation: A Case Report and Literature Review.

BACKGROUND: Gaucher disease (GD) is the most common lysosomal storage disease and requires long-term enzyme replacement therapy (ERT), which is costly and inconvenient for resource-limited countries such as Thailand. The authors present the case of a 1-year-old boy who was diagnosed with GD type 1 with a homozygous mutation at c.1448 T>C (L444P). He was treated with ERT and matched sibling hematopoietic stem cell transplantation (HSCT) was performed 6 months after the ERT was initiated. At a 3-year follow-up after the HSCT, he had full engraftment and the Lyso-GL1 levels were also at an acceptable level, which indicated disease remission. In conclusion, the authors suggest HSCT for long-term remission of GD in children.

Outcome and Prognostic Factors of Childhood Hodgkin Disease: Experience From a Single Tertiary Center in Thailand.

In childhood, Hodgkin disease (HD) has an excellent outcome in developed countries. There are few studies on outcomes of HD from resource-limited countries. This study aimed to assess clinical outcomes and factors associated with survival rates of childhood HD in a tertiary care center in Thailand. We retrospectively reviewed the medical records of pediatric HD patients between March 1985 and August 2017. Seventy-two children diagnosed with HD were identified. Pretreatment clinical and laboratory factors were assessed by Cox regression analysis to predict event-free survival (EFS) and overall survival (OS). The overall 5-year EFS and OS rate was 70.7% and 75.5%, respectively. Multivariate analysis identified 3 factors predicting inferior EFS: high-risk group (stages III-B, IV-B), splenomegaly, and platelet count >400,000/µL. The prognostic markers were assigned a score of 1 for each factor. For a total score of 0, the 5-year EFS and OS rates were 95% and 86%; scores 2 to 3, 33% and 54%, respectively. In conclusion, our study identified 3 factors predicting inferior EFS. These adverse prognostic factors can be used in clinical practice for predicting outcomes in pediatric HD.

Survival Outcome of Alternative Medicine Treatment for Newly Diagnosed Acute Leukemia in Children.

BACKGROUND: There is scarce information on the efficacy of alternative medicine (AM) alone as a treatment for newly diagnosed acute leukemia in children. We aimed to compare overall survival (OS) between children with newly diagnosed acute leukemia who received AM alone as the first-line treatment and those treated with conventional chemotherapy (CCT). METHODS: Two-to-one nearest-neighbor propensity score-matching using sex, initial white blood cell count, phenotype of leukemia, and period of diagnosis was performed on 184 patients who received CCT and 92 who received AM alone after being diagnosed with leukemia. A multivariable Cox proportional-hazards regression model was then applied to assess the effect of treatment on OS after adjusting for potential confounders. Hazard ratios (HR) and 95% confidence intervals (CI) are provided. RESULTS: After adjusting for initial white cell count and subtype of leukemia, children treated with AM alone had worse OS (HR 5.14, 95% CI 3.75-7.04) than those given CCT. The 5-year OS rate for newly diagnosed acute leukemia treated with AM medicine alone was 0%. CONCLUSION: AM without CCT is associated with poorer survival when compared with CCT.

Clinical Course and Outcome of Childhood Acquired Platelet Dysfunction with Eosinophilia.

Acquired platelet dysfunction with eosinophilia (APDE) is a syndrome which manifests as a transient state of platelet dysfunction in the presence of eosinophilia. The aim of this work was to study the clinical course and outcomes of children diagnosed with APDE. The hospital records of children with APDE were retrospectively reviewed and a total of 69 children were included. The mean (standard deviation) age at diagnosis was 6.9 (3.1) years. All of the patients presented with ecchymoses on the extremities, body, and face. None had serious bleeding symptoms. Platelet counts were within the normal range but all of the patients had abnormal platelet morphology by light microscopy. Parasitic infestation was found in 38% and most (87%) were treated with antiparasitic drugs. The median time from the onset of symptoms to remission was 2.6 months (95% CI 1.8-3.1). The overall complete remission rates at 3, 6, and 12 months were 61, 90, and 94%, respectively, with a median follow-up time after remission of 14.0 months (interquartile range 6.0-30.8). Neither univariate nor multivariate analysis indicated any statistically significant determinants for remission time. In our study, APDE was transient with spontaneous remission, no serious bleeding manifestations, and had a benign clinical course.

Prevalence and predictors of cardiac and liver iron overload in patients with thalassemia: A multicenter study based on real-world data.

Prevalence of cardiac and liver iron overload in patients with thalassemia in real-world practice may vary among different regions especially in the era of widely-used iron chelation therapy. The aim of this study was to determine the prevalence of cardiac and liver iron overload in and the management patterns of patients with thalassemia in real-world practice in Thailand. We established a multicenter registry for patients with thalassemia who underwent magnetic resonance imaging (MRI) as part of their clinical evaluation. All enrolled patients underwent cardiac and liver MRI for assessment of iron overload. There were a total of 405 patients enrolled in this study. The mean age of patients was 18.8±12.5years and 46.7% were male. Two hundred ninety-six (73.1%) of patients received regular blood transfusion. Prevalence of cardiac iron overload (CIO) and liver iron overload (LIO) was 5.2% and 56.8%, respectively. Independent predictors for iron overload from laboratory information were serum ferritin and transaminase for both CIO and LIO. Serum ferritin can be used as a screening tool to rule-out CIO and to diagnose LIO. Iron chelation therapy was given in 74.6%; 15.3% as a combination therapy.

Clinical outcome of childhood chronic immune thrombocytopenia: A 38-year experience from a single tertiary center in Thailand.

BACKGROUND: There is limited information on long-term follow-up and prognostic factors for remission among children diagnosed with chronic immune thrombocytopenia (ITP). The aim of this study was to determine clinical outcomes and factors influencing remission in childhood chronic ITP. STUDY DESIGN: The hospital records of children aged 0-15 years diagnosed with chronic ITP were retrospectively reviewed. Kaplan-Meier curves were fit to estimate the median time to complete remission with 95% confidence intervals (CIs). Multivariate Cox proportional hazards regression models were used to identify independent factors for remission. RESULTS: A total of 113 patients were included in the analysis. The number of children achieving complete remission was 49 (46%) and the median time to remission was 7.1 years (95% CI: 4.8-11.0). The remission rates at 3, 5, 10, and 20 years were 25, 43, 60, and 75%, respectively. Factors influencing remission were platelets >60 × 109 /L at the onset of chronic ITP (hazard ratio [HR]: 7.24, 95% CI: 3.0-17.5) and treatment with intravenous immunoglobulin (HR: 0.37, 95% CI: 0.16-0.84). Age, gender, and clinical factors at the time of newly diagnosed ITP including bleeding manifestations, onset of symptoms, and history of preceding infection and vaccination were not predictive of remission. CONCLUSION: The spontaneous complete remission rates of chronic ITP were 43 and 60% at 5 and 10 years, respectively, and reached 75% at 20 years. A higher platelet level at diagnosis of chronic ITP and form of treatment were statistically significant indicators for achieving complete remission.

Predictive factors for resolution of childhood immune thrombocytopenia: Experience from a single tertiary center in Thailand.

BACKGROUND: Initial clinical factors that can reliably predict a successful within-1-year resolution of childhood immune thrombocytopenia (ITP) are still unclear. This study aimed to determine factors associated with within-12-month resolution of newly diagnosed childhood ITP. METHODS: The hospital records of 417 consecutive children aged less than 15 years with ITP were reviewed retrospectively and data related to the initial presentation were noted. Logistic regression analysis was used to determine which presenting features were associated with a favorable outcome within 12 months. RESULTS: Significant clinical and laboratory predictors for resolution of newly diagnosed childhood ITP within 12 months were abrupt onset less than 14 days, age less than 5 years, and platelet count at 4 weeks postdiagnosis of at least 100 × 109 l-1 . With these three significant predictors, the rate of within-1-year recovery was more than 97.2%, with a positive predictive value of 97.8% for newly diagnosed childhood ITP. CONCLUSION: Age less than 5 years, onset of bleeding less than 14 days, and follow-up platelet count at 4 weeks of at least 100 × 109 l-1 are significant predictive factors for disease resolution among children with newly diagnosed ITP.

Gene expression ratio as a predictive determinant of nelarabine chemosensitivity in T-lymphoblastic leukemia/lymphoma.

BACKGROUND: Nelarabine has been used for the treatment of T-cell malignancies including T-acute lymphoblastic leukemia (T-ALL)/T-lymphoblastic lymphoma. However, the mechanisms that underlie the susceptibility or resistance to nelarabine have not been fully elucidated. The aim of this study was to determine the significance of nelarabine transport and metabolism in the context of nelarabine cytotoxicity. PROCEDURE: The expression profiles of six genes in the nelarabine pathway were analyzed in blast cells from six patients with T-ALL as well as in three T-ALL cell lines. In vitro cytotoxicity (LC50 of 9-ß-d-arabinofuranosylguanine [ara-G]) was evaluated. RESULTS: The mRNA expression of ENT1, DCK, CDA, NT5C2, RRM1, and RRM2 in patients showed inter-individual variability and was not correlated with the LC50 of ara-G. However, the ratio of (ENT1 × DCK)/(CDA × RRM1) expression was significantly correlated with LC50 (r = -0.831, P = 0.0405). CONCLUSIONS: Chemosensitivity to nelarabine is influenced by the balance of the expression of these four genes, and the ratio of their expression predicts the response of T-cell malignancies to nelarabine.

Two Fatal Cases of Accidental Intrathecal Vincristine Administration: Learning from Death Events.

We report 2 cases of accidental intrathecal vincristine administration. These injections were scheduled as intravenous injections of vincristine at the same time as other intrathecal drugs were scheduled. The mistakes were recognized immediately after administration, and a lumbar puncture was performed to lavage the cerebrospinal fluid (CSF) immediately after the incident. However, both cases developed progressive sensorimotor and radiculo-myelo-encephalopathy and the patients died 3 and 6 days after the incidents due to decerebration. A number of cases of accidental intrathecal vincristine administration have occurred in recent years in other settings, and we add our events to emphasize the need for a preventative and strictly followed protocol in oncology treatment units to prevent further unnecessary deaths. The best 'cure' for mistakenly administered vincristine via lumbar puncture is prevention, which can be improved by strict adherence to a comprehensive guideline. Oncologic treatment centers should be aware of this guideline and evaluate their protocol for vincristine administration to prevent future incidents. Based on our past experiences, we strongly recommend 'time-independent' procedures to prevent this type of incident.