FVIII inhibitor surveillance in children with hemophilia A in Indonesia: a report from the Indonesian Pediatric Hematology-Oncology Working Group.

Background: Factor VIII (FVIII) inhibitor diagnosis and surveillance in Indonesia are challenging owing to geographic conditions and the lack of laboratory facilities nationwide for inhibitor assays. This study aimed to determine the prevalence of FVIII inhibitors in children diagnosed with hemophilia A (HA) in Indonesia. Methods: A cross-sectional study was conducted in 12 hospitals in eight provinces of Indonesia between 2020 and 2021. Factor VIII inhibitor screening was performed in a central hemostasis laboratory for all children with HA (≤18 yr) who had received a minimum of 10 exposure days to clotting factor concentrates. The FVIII inhibitor titer was determined using the Bethesda assay. Results: Children (388) were enrolled in this study, including 219 (56.4%), 131 (33.8%), and 38 (9.4%) with severe, moderate, and mild HA, respectively. The prevalence of children who developed FVIII inhibitors was 37 out of 388 (9.6%). Factor VIII inhibitors were found in 25/219 (11.4%) severe, 11/131 (8.3%) moderate, and 1/38 (2.6%) children with mild HA. Thirteen children had low-titer inhibitors and 24 had high-titer inhibitors, with a median of 9.44 (1.48‒412.0) Bethesda Units. Among 13 children with low-titer inhibitors, eight underwent a confirmation test, of which five tested negative and were classified as transient. A significant difference in annual joint bleeding rate was found between patients with low and high inhibitor titers and those without inhibitors (P＜0.001). Conclusion: Factor VIII inhibitor prevalence in Indonesia was relatively low. However, the risk factors that may contribute to FVIII inhibitor development among Indonesian patients require further study.

Pharmacokinetic profile of children with haemophilia A receiving low-dose FVIII prophylaxis in Indonesia: A single centre experience.

BACKGROUND: Pharmacokinetic (PK) studies of low-dose prophylaxis (LDP) of coagulation factor VIII (FVIII) in children with severe haemophilia A (SHA) are scarce. OBJECTIVE: This study aims to investigate the PK profile of children with SHA receiving LDP of FVIII. METHODS: Paediatric patients receiving FVIII infusions (10 IU/kg twice weekly) were included. PK profiles were estimated using the Web Accessible Population Pharmacokinetic Service for Haemophilia (WAPPS-Haemo). The primary outcomes were the terminal half-life (t1/2 ), concentration-time profile, and time to reach an FVIII level of < 1%. The secondary outcome was the suggested dosing interval of FVIII prophylaxis based on the individual PK profile. RESULTS: Twenty-five patients were recruited; their mean age was 12.3 ± 3.0 years. The t1/2 differed among patients receiving LDP of FVIII twice weekly, with a median of t1/2 was 14.8 h (IQR 12.6-16). The median time to reach an FVIII level of < 1% was 73.8 h (IQR 58.8-80.3). Most patients could maintain a trough level of FVIII > 1% longer than 48 h. At 72-96 h, patients needed a second dose of FVIII infusion because the FVIII level was < 1%. The suggested dosing interval of FVIII prophylaxis ranged from daily to every 96 h, depending on the individual PK profile. CONCLUSION: Our study identified inter-individual differences in the PK parameters using LDP of FVIII twice weekly. The inter-individual results in different dosing intervals advise the timing of LDP. Estimating individual PK parameters enables the identification of the optimal prophylaxis frequency to prevent bleedings.

Hematological Parameters in Individuals with Beta Thalassemia Trait in South Sumatra, Indonesia.

Background: ß-Thalassemia has a very wide clinical variation, depending on the severity of the patient's condition. Individuals with ß-thalassemia traits are usually asymptomatic; however, laboratory examination will show mild anemia with microcytic hypochromic erythrocytes morphology with wide variation depending on the genotype. This study was conducted to determine the reference value of hematological parameters and hemoglobin (Hb) analysis based on the phenotype of ß-thalassemia (ß 0 and ß +) and determine the differences of hematological characteristics between the two phenotypes. Methods: This cross-sectional study was conducted by evaluating the hematological parameters and Hb analysis of the ß-thalassemia trait in the family of thalassemia patient population. The subjects were divided into ß 0 and ß +. The subject with normal Hb analysis with or without iron deficiency was excluded. Results: A total of 203 subjects with thalassemia traits were included from the families of thalassemia patients, consisting of 101 subjects with ß 0-thalassemia, 82 subjects with ß +-thalassemia, and the mutation had not been found in 20 subjects. There was a relationship in the mean/median of hematological parameters, HbA2 and HbF, between ß 0-thalassemia and ß +-thalassemia (P < 0.05). ROC for each hematological parameter, HbA2 and HbF, showed that the highest diagnostic value based on the area under the curve was mean corpuscular hemoglobin (MCH) (0.900) and mean corpuscular volume (MCV) (0.898). The cutoff point of MCH for ß 0-thalassemia trait was ≤20.5 pg (sensitivity 85%, specificity 90%) and MCV was ≤66.8 fL (sensitivity 87%, specificity 87%). Conclusion: MCH values can be used as a screening tool for predicting ß 0-thalassemia in the relatives of thalassemia patients in the South Sumatra population.

TPMT Genetic Variability and Its Association with Hematotoxicity in Indonesian Children with Acute Lymphoblastic Leukemia in Maintenance Therapy.

PURPOSE: Hematotoxicity monitoring in children with acute lymphoblastic leukemia (ALL) is critical to preventing life-threatening infections and drug discontinuation. The primary drug that causes hematotoxicity in ALL children is 6-mercaptopurine (6-MP). Genetic variability of the drug-metabolizing enzymes of 6-MP, thiopurine S-methyltransferase (TPMT), is one factor that might increase the susceptibility of children to hematotoxicity. The present study aimed to determine the variability in TPMT genotypes and phenotypes and its association with the occurrence of hematotoxicity in ALL children in maintenance therapy. PATIENTS AND METHODS: A cross-sectional study was conducted at Cipto Mangunkusumo and Dharmais National Cancer Hospital, Jakarta, Indonesia, from June 2017 to October 2018. We included ALL patients, 1-18 years, who were receiving at least one month of 6-MP during maintenance therapy according to the Indonesian protocol for ALL 2013. Direct sequencing was used to determine TPMT*3A, *3B, and *3C genotypes, and LC-MS/MS analysis was performed to measure the plasma concentrations of 6-MP and its metabolites. Association analysis between the TPMT genotype and hematotoxicity was evaluated using the unpaired t-test or Mann-Whitney's test. RESULTS: The prevalence of neutropenia, anemia, and thrombocytopenia in ALL children during maintenance therapy was 51.9%, 44.3%, and 6.6%, respectively. We found a low frequency of TPMT*3C, which is 0.95%. No association was found between hematotoxicity and TPMT genotypes or age, nutritional status, serum albumin levels, risk stratification, the daily dose of 6-MP, and cotrimoxazole co-administration. However, hematotoxicity was associated with 6-methylmercaptopurine (6-MeMP) plasma concentrations and the ratio 6-MeMP/6-thioguanine (6-TGN). We also found no association between TPMT genotypes and TPMT phenotypes. CONCLUSION: The 6-MeMP/6-TGN ratio is associated with hematotoxicity in ALL children during maintenance therapy but is not strong enough to predict hematotoxicity.

Effects of α-tocopherol on hemolysis and oxidative stress markers on red blood cells in ß-thalassemia major.

BACKGROUND: The accumulation of unpaired α-globin chains in patients with ß-thalassemia major may clinically create ineffective erythropoiesis, hemolysis, and chronic anemia. Multiple blood transfusions and iron overload cause cellular oxidative damage. However, α-tocopherol, an antioxidant, is a potent scavenger of lipid radicals in the membranes of red blood cells (RBCs) of patients with ß-thalassemia major. PURPOSE: To evaluate the effects of α-tocopherol on hemolysis and oxidative stress markers on the RBC membranes of patients with ß-thalassemia major. METHODS: Forty subjects included in this randomized controlled trial were allocated to the placebo and α-tocopherol groups. Doses of α-tocopherol were based on Institute of Medicine recommendations: 4-8 years old, 200 mg/day; 9-13 years old, 400 mg/day; 14-18 years old, 600 mg/day. Hemolysis, oxidative stress, and antioxidant variables were evaluated before and after 4-week α-tocopherol or placebo treatment, performed before blood transfusions. RESULTS: Significant enhancements in plasma haptoglobin were noted in the α-tocopherol group (3.01 mg/dL; range, 0.60-42.42 mg/dL; P=0.021). However, there was no significant intergroup difference in osmotic fragility test results; hemopexin, malondialdehyde, reduced glutathione (GSH), or oxidized glutathione (GSSG) levels; or GSH/GSSG ratio. CONCLUSION: Use of α-tocopherol could indirectly improve hemolysis and haptoglobin levels. However, it played no significant role in oxidative stress or as an endogen antioxidant marker in ß-thalassemia major.

Comparison of the efficacy and safety of 12-month low-dose factor VIII tertiary prophylaxis vs on-demand treatment in severe haemophilia A children.

INTRODUCTION: Prophylaxis has commonly become standard treatment for severe haemophilia patients. The World Federation of Hemophilia (WFH) recommends low-dose prophylaxis in countries with resource constraints. OBJECTIVE: To determine efficacy and safety of low-dose factor VIII (FVIII) tertiary prophylaxis compared to on-demand treatment in severe haemophilia A children in Indonesia. METHODS: Eligible patients were randomly assigned to prophylaxis and on-demand groups. Patients in the prophylaxis group received infusion of FVIII 10 IU/kg body weight, two times per week. Primary outcomes were the numbers of joint bleeding and total bleeding episodes; secondary outcomes were evidence of FVIII inhibitor, Hemophilia Joint Health Score (HJHS) and Hemophilia Early Arthropathy Detection Ultrasound (HEAD-US) score. Patients were monitored for 12 months. RESULTS: Fifty patients, all with tertiary prophylaxis, 4-18 years of age, were randomized into prophylaxis (n = 25) and on-demand (n = 25) groups. The mean follow-up time was 12.8 ± 0.86 vs 12.3 ± 0.54 months, respectively. Numbers of total and joint bleeding episodes were significantly lower in the prophylaxis group (P < 0.001, 95% CI -24.6;-10.7 and P < 0.001, 95% CI -14;-3, respectively). The prophylaxis group showed improvement of joint function (P = 0.004; CI 95% -3;-0.5); on the contrary, we found deterioration in the on-demand group (P = 0.001; CI 95% 1;3). HEAD-US scores showed improvement at month 6 in the prophylaxis group, but there was no significant difference between groups at month 12. CONCLUSION: Low-dose FVIII tertiary prophylaxis was effective in reducing joint bleeding episodes and improvement of HJHS compared to on-demand FVIII treatment in severe haemophilia A children.

Pneumococcal vaccination for splenectomized patients with thalassemia major in Indonesia.

INTRODUCTION: Streptococcus pneumoniae is a capsulated bacterium that can cause severe infection in patients with thalassemia major, particularly those who have undergone splenectomy. The absence of the spleen as well as zinc deficiency in splenectomized patients with thalassemia major increases the possibility of developing invasive pneumococcal infection. The aims of this study are to evaluate pneumococcal IgG levels following PCV and PPV immunizations and the effect of zinc supplementation on qualitative specific immune responses in splenectomized patients with thalassemia. METHODS: Splenectomized patients with thalassemia major were administered a PCV pneumococcal vaccine (Prevenar 13®) at the start of the trial, after which they were randomly assigned to 2 groups (zinc and placebo group). After 8weeks, the patients received a PPV pneumococcal vaccine (Pneumovax®). Zinc syrup was provided to the zinc group at a dose of 1.5mg/kg/day (maximum of 50mg/day). Pneumococcal IgG examinations were conducted at the start of the trial and after 12weeks. RESULTS: In the group without PPV, the median initial pneumococcal IgG value was 315 (ranging from 65 to 1419) mU/mL for the zinc group and 338.5 (ranging from 82 to 1648) mU/mL for the placebo group. The median final pneumococcal IgG value was 1812.5 (ranging from 834 to 2444) mU/mL for the zinc group and 2857.5 (ranging from 834 to 2624) for the placebo group. The increase in the pneumococcal IgG value between the two groups was comparable (p=0.642). In the group with previous PPV, the median initial pneumococcal IgG value was 1333 (ranging from 793 to 2031) mU/mL for the zinc group and 880 (ranging from 74 to 1686) mU/mL for the placebo group. The median final pneumococcal IgG value was 1487 (ranging from 635 to 1757) mU/mL for the zinc group and 1012 (ranging from 292 to 1732) mU/mL for the placebo group. The increase in the pneumococcal IgG value between the two groups was comparable (p=0.528). CONCLUSION: There is no difference in the increase in pneumococcal IgG level in splenectomized patients with thalassemia major prior to and after receiving PPV. There were no differences observed in the development of pneumococcal IgG following zinc supplementation.

Integrative Approach in Haemophillic Arthropathy of The Knee: a Case Report.

Haemophilic arthropathy is the most prevalent joint disorder in haemophilia. This disorder is characterized by chronic synovitis and progressive destruction of joint cartilage. We report a case of arthroscopic synovectomy to reduce bleeding frequency in haemophilic arthropathy of the knee. Patient was a 15 years old male with haemophilic arthropathy of the left knee. We performed an arthroscopic synovectomy under tightly regulated factor VIII replacement therapy. There were villous synovial hypertrophy at all part of the joint, multiple bone and cartilage defect, and also anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) deficiency found intraoperatively. After 6 month follow up, subjective complain and bleeding frequency decreased significantly. The visual analog scale improved from 5-6 to 1-2, and the International Knee Documentation Committee Score increased from 49 to 66. Bleeding frequency decreased from 4-8 times per month to less than 1 time per month. Arthroscopic synovectomy performed in this case could reduce the pain, decrease the frequency of bleeding, and improve patient's functional outcome.

Immune response of thalassemia major patients in Indonesia with and without splenectomy.

AIM: to describe non-spesific and specific immune response profile in Indonesian thalassemia major with and without splenectomy. METHODS: this study was held at Thalassaemia Centre, Cipto Mangunkusumo Hospital Jakarta on September 2013-February 2014. A comparative cross sectional study was conducted in healthy, thalassemia major aged more than 12 year and seronegative HIV. They were matched in age and sex for splenectomised and non-splenectomised groups, analysing the non-spesific immune response (neutrophil count and phagocytosis) and specific immune response (count and function of cellular immunity). Infection episodes were also analized as immune response in vivo parameter. RESULTS: splenectomised thalassemia major showed increased neutrophil count but significantly decreased non-spesific immune response (neutrophil phagocytosis). Spesific immune response of splenectomised group presented significantly higher absolute lymphocyte, lymphocyte T, CD4+ and CD8+ counts compared to non-splenectomised thalassemia major (p<0.05). Ratio CD4+/CD8+ were similar in these groups. Serum marker of activated cellular imunity function (IL-2 and TNF-) were similar among two groups. Mild infection episodes on splenectomised and non-splenectomised group were 2.02 (ranged 0 to 12) times and 0.81 (ranged 0 to 8) times (p=0.004), respectively. Severe infection on splenectomised group were sepsis for 2 weeks and diarrhea for 1 week, whereas on non-splenectomised group was typhoid fever for 4 days. CONCLUSION: there were significant differences on immune response among thalassemia major patients. Splenectomised thalassemia major showed a greater degree of susceptibility to infections than non-splenectomised thalassemia major.

A 65 bp deletion in band 3 gene of beta-thalassemia patients in Indonesia.

We investigated whether in addition to the well known genetic alteration in red blood cell membrane band 3 protein, a deletion of 9 amino acids leading to ovalocytosis, other mutations to band 3 also exist. In 12% of our thalassemia major patients investigated, we found two bands in the agarose gel-electrophoresis of PCR products from band 3 gene with a difference of 65 +/- 10 bp, equivalent to a deletion of 20 to 25 amino acids in band 3 protein. Thus, a co-existing band 3-mutant allele in addition to the thalassemic globin gene defects, could also contribute to erythrocyte membrane defects and to the spectrum of clinical symptoms of these thalassemia major patients.

Correlation between T2* cardiovascular magnetic resonance with left ventricular function and mass in adolescent and adult major thalassemia patients with iron overload.

AIM: to assess for a correlation between T2*CMR with LV function and mass in thalassemic patients with iron overload. METHODS: a cross-sectional study on thalassemic patients was conducted between July and September 2010 at Cipto Mangunkusumo and Premier Hospitals, Jakarta, Indonesia. Clinical examinations, review of medical charts, electrocardiography, echocardiography, and T2*CMR were performed. Cardiac siderosis was measured by T2*CMR conduction time. Left ventricle diastolic and systolic functions, as well as LV mass index were measured using echocardiography. Correlations between T2*CMR and echocardiography findings, as well as serum ferritin were determined using Pearson's and Spearman's tests. RESULTS: thirty patients aged 13-41 years were enrolled, of whom two-thirds had -thalassemia major and one-third had HbE/-thalassemia. Diastolic dysfunction was identified in 8 patients, whereas systolic function was normal in all patients. Increased LV mass index was found in 3 patients. T2*CMR conduction times ranged from 8.98 to 55.04 ms and a value below 20 ms was demonstrated in 14 patients. There was a statistically significant moderate positive correlation of T2*CMR conduction time with E/A ratio (r = 0.471, P = 0.009), but no correlation was found with LV mass index (r=0.097, P=0.608). A moderate negative correlation was found between T2*CMR and serum ferritin (r = -0.514, P = 0.004), while a moderate negative correlation was found between serum ferritin and E/A ratio (r = -0.425, P = 0.019). CONCLUSION: T2*CMR myocardial conduction time has a moderate positive correlation with diastolic function, moderate negative correlation with serum ferritin, but not with LV mass index and systolic function.