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Hemoglobin (Hb) H disease presents a wide range of clinical phenotypes, from asymptomatic to severe forms, depending on significant genetic heterogeneity. This is the first report of clinical and hematological features of the nondeletional HbH disease caused by --CR/αCSα. A baby was born to a father and a mother with --CR and αCSα carriers, respectively. She had severe symptomatic hypochromic microcytic anemia at 2 months of age with Hb 7.8 g/dL, packed cell volume (PCV) 0.27 L/L, mean corpuscular volume (MCV) 64.3 fL, and mean corpuscular Hb (MCH) 18.3 pg. The Hb analysis using capillary electrophoresis (CE) showed Hb Bart's, HbH, and Hb CS peaks at 17.1%, 2.2%, and 1.6%, respectively. A better understanding of a patient's clinical and hematological features with --CR/αCSα is useful for hemoglobinopathy counseling for the national thalassemia controlling program. [ABSTRACT FROM AUTHOR]

Introduction: Hereditary pyropoikilocytosis (HPP) is the most common cause of non‐thalassemic severe inherited hemolytic anemia in Thai population. Up to 90% of affected patients harbor biallelic mutations of SPTB Providence (SPTB c.6055T>C), SPTB Buffalo (SPTB c.6074T>G), and SPTB Chiang Mai (SPTB c.6224A>G). This study aimed to develop a simple assay for mass screening of the three common SPTB mutations and to study their carrier frequencies in a healthy Thai population. Methods: We combined multiplex amplification refractory mutation system‐PCR (ARMS‐PCR) and high‐resolution melting (HRM) curve analysis to create a one‐step single‐tube assay. The primers were designed to generate products with different melting temperatures in the presence of 6055C, 6074G, and 6224G. Internal control primers were added for quality control. Residual samples from blood donors and healthy adolescents were collected and tested for the three common SPTB mutations using the newly developed assay. Results: Optimized multiplex ARMS‐PCR/HRM curve assay yielded well‐separated melt curves to detect the three SPTB mutations with 4‐h turnaround time. The assay was validated in screening of 2261 non‐repetitive blood donors and 89 adolescents, in which 10 (0.43%), 2 (0.09%), and 3 (0.13%) individuals were identified as carriers of SPTB Providence, SPTB Buffalo, and SPTB Chiang Mai, respectively. All mutated SPTB and 20 random wild‐type samples were confirmed using Sanger sequencing with 100% accuracy. Conclusion: The novel ARMS‐PCR/HRM curve assay is simple, accurate, and time‐effective for mass screening of the common SPTB mutations. This can be employed to prevent HPP birth in a Thai population. [ABSTRACT FROM AUTHOR]

The study aimed to determine efficacy and safety of generic deferasirox monotherapy. Deferasirox was administered in transfusion-induced iron overloaded thalassemia. Efficacy was defined as responders and nonresponders by ≤ 15 reduced serum ferritin from baseline. Adverse events were also monitored. Fifty-two patients with mainly Hb E/β-thalassemia at the mean (SD) age of 8.7 (4.1) years, were enrolled. The mean (SD) daily transfusion iron load was 0.47 (0.1) mg/kg and maximum daily deferasirox was 35.0 (6.2) mg/kg. Altogether, 52, 40 and 18 patients completed the first, second and third years of study, respectively. The median baseline serum ferritin 2,383 ng/mL decreased to 1,478, 1,038 and 1,268 ng/mL at the end of first, second and third years, respectively, with overall response rate at 73.1% (38/52). Patients with baseline serum ferritin >2,500 ng/mL showed a change in serum ferritin higher than those ≤2,500 ng/mL starting from the 9th month of chelation. Adverse events were found in 5 of 52 patients (9.6%) including transaminitis (n = 2), one each of proteinuria, rash and proximal tubular dysfunction which resolved after transient stopping or decreasing the chelation dose. Generic deferasirox was effective and safe among pediatric patients with transfusion-induced iron overloaded thalassemia. [ABSTRACT FROM AUTHOR]

This article discusses the transfer of data from the Thai haemophilia treatment center registry to the Annual Global Survey (AGS) of the World Federation of Hemophilia (WFH). The data collection aims to improve care for patients with hereditary bleeding disorders by identifying available treatment resources, evaluating their effectiveness, and advocating for better care. The Thai Society of Haematology (TSH) initiated the Haemostasis Registry, which includes the Hereditary Bleeding Disorders Registry (HBDR) and Thrombosis. The data from the HBDR is transferred to the World Bleeding Disorders Registry (WBDR) and the AGS of the WFH. This data transfer reduces redundancy and improves the reliability, accuracy, cost-effectiveness, and efficiency of data collection. The article highlights the importance of the AGS in collecting data on patients with hereditary bleeding disorders and the treatments used worldwide. The data collected through the AGS is used for resource planning, advocacy, research, and development activities to improve the management of patients with these disorders. The authors emphasize the need for collaboration between clinicians and information technology personnel to ensure accurate data input and output. The dataset of the World Bleeding Disorders Registry and the questionnaire of the AGS are recommended as useful templates for data collection and reporting. The study was conducted ethically and the data is available upon request. [Extracted from the article]

Background: Hemophilia cannot be diagnosed in most laboratories of economically less-developed countries leading to high mortality and morbidity rates.Aim: A diagnostic tool was established ranging from bleeding assessment and a simple bedside test of mixing venous clotting time (VCT) to comprehensive DNA analysis for patients with hemophilia.Methods: Patients with known (n=80) and suspected hemophilia (n=14) were included. Their bleeding symptoms were initially evaluated using verified translated-Thai ISTH bleeding assessment tool. Then, blood samples were drawn using a two-syringe technique, 2 mL each was placed in three tubes, for the mixing VCT and citrate blood was kept for coagulogram and coagulation factor assay. Finally, DNA analysis was determined.Results: A total of 94 patients with hemophilia (A68, B26) defined as severe (A 57, B 17), moderate (A 7, B 5), and mild degrees (A 4, B 4) with the mean (SD) age of 14.0 (11.7) years and 24 normal controls aged 25.5 (4.5), were enrolled in the study. The mean (SD) bleeding score of patients with hemophilia was 13.5 (5.5), which did not significantly differ between patients with hemophilia A and B. The mixing venous clotting time offered the presumptive diagnosis of hemophilia A and B, which were subsequently confirmed by the prolonged APTT, low FVIII:C and FIX:C and mutations on the factor VIII and IX genes.Conclusion: A diagnostic tool for bleeding assessment, mixing venous clotting time, coagulogram, coagulation factor assay, and DNA analysis for patients with hemophilia has been established in the existing health-care system. [ABSTRACT FROM AUTHOR]

Background: Thromboembolism can occur at any age, from infancy to adulthood. The genetic risk factors for thromboembolism in the Thai population are protein C and protein S mutations. The diagnosis depends on the activity level of proteins in the plasma. Management of acute thrombotic events in severe protein C deficiency typically requires replacement with protein C in the form of fresh frozen plasma or protein C concentrate. At present, the measurement of protein C and protein S activities level is limited due to the cost and availability of the tests. Therefore, it can take a lengthy time to determine protein C levels, resulting in a delay in treatment, especially in severe cases. Objective: To create an antibody library on filamentous bacteriophage for generating antigen specific monoclonal antibodies and to produce polyclonal antibodies specific to protein C. Results: Recombinant protein C was constructed and produced from human embryonic kidney 293 cells. Protein C was used as an antigen to immunize mice and rabbits. The antibody titers after final boosting immunization reached up to 50,000 in mice and 10,000 in rabbits. The phage antibody library with a capacity of approximately 3×105 CFU was obtained from mice lymphocytes. Polyclonal antibodies were purified from rabbit sera using affinity chromatography and achieved a yield of 2 mg/mL rabbit sera. The purified polyclonal antibodies were able to detect protein C by immunoblotting and ELISA. Conclusion: The present study demonstrated that polyclonal antibodies could be produced from immunized rabbits and the antibody library obtained from immunized mice is beneficial for further isolation of monoclonal antibodies against protein C. [ABSTRACT FROM AUTHOR]