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.

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.

Molecular and haematological characterisation of haemolytic anaemia associated with biallelic KLF1 mutations: a case series

AIMS

Krüppel-like factor 1 (KLF1) is an erythroid-specific transcription factor playing an important role in erythropoiesis and haemoglobin (Hb) switching. Biallelic KLF1 mutations can cause haemolytic anaemia with thalassaemia-like syndromes but are rarely reported. We explore the KLF1 mutations in Thai subjects with unexplainable haemolytic anaemia.

METHODS

The study was done on 57 subjects presented with haemolytic anaemia and elevated Hb F without β-thalassaemia diseases. Hb analysis was performed using capillary electrophoresis. Analyses of α-thalassaemia, β-thalassaemia and KLF1 genes were performed using PCR-based methods and DNA sequencing.

RESULTS

Thirteen subjects with compound heterozygous for a known and five new genetic KLF1 interactions were identified, including KLF1:c.519_525dupCGGCGCC/c.892G>C with class 3/2 (n=8), and each subject with new genetic interaction, including KLF1:c.-154C>T;643C>T/c.983G>A with class 3/2, KLF1:c.-154C>T;643C>T/c.809C>G with class 3/2, KLF1:c892G>C/c.983G>A with class 2/2, KLF1:c.892G>C/c.1001C>G with class 2/2 and KLF1:c.1001C>G/c.1003G>A with class 2/2. Most of them had anaemia with Hb levels ranging from 45 to 110 g/L, hypochromic microcytosis, aniso-poikilocytosis, increased Hb F levels (17.9%-47.4%), small amounts of Hb Bart's, regular blood transfusion, hyperbilirubinaemia, increased serum ferritin and nucleated red blood cell.

CONCLUSIONS

Biallelic KLF1 mutations associated with anaemia may not be uncommon in Thailand. Characteristics of haemolytic anaemia, abnormal red cell morphology with nucleated red blood cells and elevated Hb F, and presenting small amounts of Hb Bart's without thalassaemia diseases are useful markers to further investigation of the KLF1 gene.

The association of growth differentiation factor-15 levels and osteoporosis in patients with thalassemia

INTRODUCTION

Ineffective erythropoiesis (IE) is a significant risk factor for osteoporosis in individuals with thalassemia. Growth differentiation factor-15 (GDF15), a biomarker of IE, was found to be elevated in thalassemia patients. This study aimed to examine the association between GDF15 levels and osteoporosis in patients with thalassemia.

METHODS

A cross-sectional study was conducted in 130 adult patients with thalassemia in Thailand. Bone mineral density (BMD) at the lumbar spine was evaluated by dual-energy X-ray absorptiometry (DXA), and with a Z-score of less than -2.0 SD was defined as osteoporosis. GDF-15 was measured using the enzyme-linked immunosorbent assay (ELISA). Logistic regression analysis was used to examine the associated factors with the development of osteoporosis. Receiver operator characteristic (ROC) curve analysis was used to estimate the threshold of GDF15 in predicting osteoporosis.

RESULTS

Osteoporosis was detected in 55.4% (72/130) of the patients. Advanced age and high GDF15 levels were positively associated with osteoporosis, while an increased hemoglobin level was negatively associated with osteoporosis in patients with thalassemia. In this study, the GDF15 level's ROC demonstrated a good performance in predicting osteoporosis (AUC=0.77).

CONCLUSIONS

The prevalence of osteoporosis is high among adult thalassemia patients. Age and high GDF15 levels were significantly associated with osteoporosis in this study. A higher hemoglobin level is associated with a lower risk of osteoporosis. This study suggest that GDF15 could be used as a predictive biomarker for osteoporosis in patients with thalassemia. Adequate red blood cell transfusions and suppression of GDF15 function may be beneficial in preventing osteoporosis.

Clinical features and risk factors of renal dysfunctions in thalassemic patients

INTRODUCTION

Chronic anemia, iron overload, and iron chelation therapy are the main contributing factors for renal complications in thalassemia, e.g., nephrolithiasis, glomerular disease, and renal tubular dysfunction. The prevalence and associated factors for developing renal dysfunctions in Thai patients with thalassemia, however, remained limited. This study aimed to determine the prevalence and risk factors of renal dysfunctions in patients with thalassemia.

METHODS

A cross-sectional study was conducted on adult patients with thalassemia disease at Srinagarind Hospital, Khon Kaen University, Thailand. All patients were evaluated for complete blood count, blood chemistry, urinalysis, and urine biochemistry. Renal tubular dysfunction was defined as existing in at least one of the following parameters including; proteinuria, hypercalciuria, hypouricemia with uricosuria, or hypophosphatemia with phosphaturia. Logistic regression analysis was used to identify associated factors for renal dysfunctions.

RESULTS

Of 105 patients, renal tubular dysfunction was found in 60 patients (57.1%). In multivariate analysis of the clinical risk factors for renal tubular dysfunction in thalassemia patients, age per 10 year increase (adjusted odds ratio [AOR] = 1.4, 95% CI: 1.0-2.0, p value 0.01) and Hb E/beta-thalassemia (AOR = 3.6, 95% CI: 1.3-10.3, p value 0.01) were statistically proven to be associated with renal tubular dysfunction. Hyperuricosuria was a significantly associated factor for microhematuria. (AOR = 2.9, 95% CI: 1.1-8.0, p value 0.03).

CONCLUSIONS

Renal dysfunctions are prevalent in thalassemia patients, with older age and Hb E/beta-thalassemia genotype as significant risk factors for renal tubular dysfunction. Hyperuricosuria is a risk factor for microhematuria. Renal dysfunctions should be recognized and monitored in aging patients with Hb E/beta-thalassemia.

FLT3 Gene Mutations in Acute Myeloid Leukemia Patients in Northeast Thailand

BACKGROUND Mutations in the FLT3 gene are associated with acute myeloid leukemia (AML). FLT3 mutations have been identified in approximately 30% of de novo AML patients, particularly those with typical karyotype and inferior prognosis. Therefore, we examined the frequencies of an internal tandem duplication (ITD) and missense mutations of the FLT3 gene and their associated clinical characteristics in patients with AML in northeast Thailand. MATERIAL AND METHODS The leftover bone marrow and/or peripheral blood specimens of 65 newly diagnosed AML patients recruited from Srinagarind Hospital, Khon Kaen University, northeast Thailand, between January 2020 and May 2021 were included in this study. FLT3-ITD and FLT3- tyrosine kinase domain (TKD) were amplified using PCR-related techniques. RESULTS The frequencies of FLT3-ITD and TKD were found to be 16.9% (11/65) and 10.8% (7/65), respectively. One patient had ITD and TKD mutations. The white blood cell count and peripheral blast percentage of FLT3-ITD-positive patients were statistically significantly higher than those of the FLT3-wild type patients, while the peripheral blast percentage of FLT3-TKD-positive patients was significantly lower. No other clinical characteristics among FLT3-positive and FLT3-wild-type patients were observed. DNA sequencing identified 4 FLT3-TKD mutations. The c.2504A>T; Asp835Val and c.2503G>C; Asp835His mutations were predicted as pathogenic mutations while the 2 novel mutations, c.2508C>A; Ile836= and c.2508C>G; Ile836Met were predicted as neutral mutations. CONCLUSIONS This study showed for the first time that FLT3-TKD mutation is common among northeast Thai AML patients. The data should prove useful for selecting efficacious targeted treatment plans for the patients.

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.

Phosphatidylserine-exposed red blood cells and ineffective erythropoiesis biomarkers in patients with thalassemia

OBJECTIVE

The degree of ineffective erythropoiesis is known to be associated with clinical severity among individuals with thalassemia. The association of ineffective erythropoiesis biomarker levels with different thalassemia genotypes, however, remains limited. The aim of this study was to explore the level of phosphatidylserine-exposed red blood cells (PS-exposed RBCs) and ineffective erythropoiesis biomarkers (growth-differentiation factor-15 and soluble transferrin receptors) in patients with different genotypes.

METHODS

A cross-sectional study was conducted on 139 patients of age 18 years and above with different genotypes at Srinagarind Hospital, Khon Kaen University, Thailand. The levels of PS-exposed RBCs were determined using flow cytometry. Measurements of growth-differentiation factor-15 (GDF-15) and soluble transferrin receptors (sTfR) were evaluated by the ELISA method.

RESULTS

The PS-exposed RBCs levels were found to be significantly higher in splenectomized beta-thalassemia patients. Patients with beta-thalassemia had the highest GDF-15 levels, followed by patients with non-deletional alpha-thalassemia. Patients with non-deletional alpha-thalassemia showed elevated hemoglobin levels and reduced GDF-15 levels after splenectomy. Patients with beta-thalassemia and non-deletional alpha-thalassemia had the highest levels of PS-exposed RBCs and ineffective erythropoiesis biomarkers, which correlated with the clinical severity of thalassemia.

CONCLUSIONS

The levels of ineffective erythropoiesis biomarkers were different across thalassemia genotypes. Splenectomy may improve clinical symptoms of patients with non-deletional alpha thalassemia but not of patients with beta-thalassemia. These findings demonstrate differences in the degree of ineffective erythropoiesis in thalassemia, which emphasizes the need for different treatment approaches among patients with different thalassemia genotypes.

Cognitive Impairment in Thalassemia and Associated Factors

INTRODUCTION

Patients with thalassemia increase the risk of developing cognitive impairment. Chronic anemia, oxidative stress from excess iron, and hypercoagulable state were related to this condition. The study regarding its prevalence and the associated factor in Southeast Asia is limited. Therefore, the study aimed to investigate the prevalence of cognitive impairment and associated factors.

METHODS

This was a cross-sectional study of thalassemic patients aged 18 years or more at the Hematology Clinic of Srinagarind Hospital, Khon Kaen University, Thailand, from January to May 2021. The Thai version of the Mini-Cog test was used to determine the presence of cognitive impairment. The clinical and laboratory parameters indicated as potential risk factors for dementia were evaluated in all patients. A stepwise logistic regression analysis was used to determine the associated risk factors for cognitive impairment.

RESULTS

Among 150 patients, cognitive impairment was found in 40 patients (26.7%). Age per 10-year increase (adjusted odds ratio [AOR] of 1.6), no iron chelation therapy (AOR of 9.8), current smoking (AOR of 5.0), hemoglobin (Hb) (AOR of 0.63), and ferritin (AOR of 1.0001) were independent factors associated with cognitive impairment.

CONCLUSIONS

The prevalence of cognitive impairment was high among thalassemic patients. Increasing age, low Hb, iron overload, and current smoking were significant associated factors with cognitive impairment. Screening for dementia in these patients is recommended, particularly in patients with high-risk factors.

Acalypha indica induced transient glucose-6-phosphate dehydrogenase deficiency with acute haemolysis

Acalypha indica is a tropical herb found in Asia. The entire plant, especially the leaves, is used in herbal medicine for several therapeutic purposes. Acute intravascular haemolysis and methaemoglobinaemia have been reported in patients who consume this herb. We present a case of a previously healthy middle-aged man who ingested boiled leaves of A. indica The patient developed clinical symptoms and signs of intravascular haemolysis 7 days after ingestion. Peripheral blood smear showed typical findings of glucose-6-phosphate dehydrogenase (G6PD) deficiency with acute haemolysis. The G6PD activity was low during active haemolysis. The G6PD level, however, returned to normal after 4 months of follow-up. The patient was further tested for common G6PD gene mutations in Southeast Asia and was negative. Ingestion of A. indica may induce transient G6PD deficiency, which in this patient led to acute haemolysis and methaemoglobinaemia.

Clinical factors predictive of recurrent febrile neutropenia in adult patients with acute leukemia

Febrile neutropenia (FN) is considered an oncologic emergency in acute leukemia. There were 250 FN events in 124 hospitalized patients with hematologic malignancy. These data imply that two FN events may occur per patient, yet data on the prevalence, risk factors, and outcomes of recurrent FN in adult patients with leukemia are limited. A retrospective cohort study was conducted that enrolled adult patients diagnosed with acute leukemia who developed FN. The eligible patients were categorized as with or without recurrent FN. A stepwise, multivariate logistic regression analysis was performed to identify predictors of recurrent FN. A total of 203 patients met the study criteria; of these, 46 (22.66%) had recurrent FN, and this group had a median of three recurrent FN emergencies. After adjusted, three independent factors remained in the final model including ALL, FN at admission, and treatment with idarubicin (3 days) and cytarabine (7 days). The three factors were positively associated with recurrent FN with adjusted odds ratios of 6.253, 4.068, and 10.757, respectively. No significant differences were found between the two groups in terms of other sources of infection, other pathogens, ICU stay, hospital stay, and mortality. ALL and FN at admission and treatment with idarubicin (3 days) and cytarabine (7 days) were associated with recurrent FN in acute leukemia patients with FN. Clinical outcomes for patients with or without recurrent FN were mostly comparable; however, due to its small sample size, further studies are required to confirm the results of this study.

The serum ferritin levels and liver iron concentrations in patients with alphathalassemia is there a good correlation?

INTRODUCTION

Liver iron overload is common in patients with thalassemia. In patients with beta-thalassemia, the correlation between serum ferritin and liver iron concentration is well established. The correlation between serum ferritin levels and liver iron concentrations in patients with alpha-thalassemia remains limited.

METHODS

This is a cross-sectional study in patients with alpha-thalassemia aged ≥ 18 years old at Srinagarind Hospital, Khon Kaen University, Thailand. Liver iron concentration (LIC) was evaluated by the MRI-T2* technique. Linear logistic regression analysis was used to determine the correlation between serum ferritin levels and liver iron concentrations.

RESULTS

One hundred and thirty-one of the MRI-T2* measurements from 65 patients with alpha-thalassemia were evaluated. Patients with non-deletional alpha-thalassemia had higher LIC compared to patients with deletional alpha-thalassemia. The serum ferritin levels were relatively low at the same levels of LIC in patients with non-deletional alpha-thalassemia compared to deletional alpha-thalassemia.

CONCLUSIONS

The correlation of serum ferritin levels and LIC was modest and different among alpha-thalassemia genotypes. A different serum ferritin threshold is needed to guide iron chelation therapy in patients with alpha-thalassemia. Evaluation of liver iron concentration is necessary for patients with alpha-thalassemia, especially in patients with non-deletional alpha-thalassemia.

Clinical factors predictive of mortality in acute leukemia patients with febrile neutropenia

BACKGROUND

Acute leukemia is mainly treated with chemotherapy leading to febrile neutropenia (FN). There is limited data on clinical factors predictive of mortality in adults with acute leukemia and FN.

METHODS

This was a retrospective cohort study and enrolled adult patients, diagnosed as acute leukemia, and developed FN. The eligible patients were admitted and followed up with mortality as the primary outcome. A stepwise, multivariate logistic regression analysis was used to find predictors for mortality.

RESULTS

There were 203 patients met the study criteria. Of those, 14 patients died (6.89%). AML was the most common type of acute leukemia with FN (64.04%). There were five remaining factors in the final model: AML, FN at admission, prolong broad spectrum antibiotics, lower respiratory tract infection, and Aspergillosis. Only lower respiratory tract infection was significant with adjusted odds ratio of 7.794 (95% CI of 1.549, 39.212). The Hosmer-Lemeshow Chi square was 2.74 (p value 0.907). The lower respiratory tract infection group had higher proportions of Gram negative and fungus than the non-lower respiratory tract infection group; specifically E. coli (p 0.003), and Aspergillus (P < 0.001).

CONCLUSIONS

There were two independent predictors of mortality in acute leukemia patients with FN: septic shock and lower respiratory tract infection regardless of leukemia type or pathogen. E. coli and Aspergillus were more common in those with lower respiratory tract infection than those without. No specific pathogens were found in cases of septic shock.

Review of disease-related complications and management in adult patients with thalassemia: A multi-center study in Thailand

Disease-related complications and management are different among patients with thalassemia. This study was aimed to review the prevalence, clinical risk factors for the complications and the management in patients with thalassemia in Thailand. A multicenter cross-sectional study was conducted in patients with thalassemia aged ≥ 18 years old. Thalassemia-related complications and management were reviewed. The clinical parameters significantly associated with the complications were analyzed by logistic regression methods. The prevalence of thalassemia-related complications was 100% in patients with transfusion-dependent thalassemia (TDT) and 58.8% in patients with non-transfusion-dependent thalassemia (NTDT). Advanced age was statistically associated with extramedullary hematopoiesis in both TDT and NTDT patients. Splenectomy was a significant risk factor for pulmonary hypertension in both groups of patients. Severe iron overload started earlier in patients with TDT than NTDT and was associated with diabetes mellitus (adjusted odds ratio (AOR) = 6.2, p-value = 0.02). Disease-related complications are more prevalent in patients with TDT than patients with NTDT. Splenectomy and advanced age were important risk factors for developing major complications in both groups. Early screening and management for specific disease-related complications should be considered in patients with thalassemia according to their clinical risk factors.

Epidemiologic study of major complications in adolescent and adult patients with thalassemia in Northeastern Thailand: the E-SAAN study phase I

INTRODUCTION

Thalassemia-related complications are one of the main factors that increase morbidity and mortality in aging patients with thalassemia. This study was aimed to report the prevalence and clinical risk factors for the complications in thalassemia.

METHODS

A multi-center prospective cohort study was conducted in patients with thalassemia aged ≥10 years old. Thalassemia-related complications were heart failure, pulmonary hypertension, extramedullary hematopoiesis, endocrine disorders, infections, thrombosis and leg ulcers. The clinical parameters significantly associated with the complications were analyzed by logistic regression methods.

RESULTS

The prevalence of thalassemia-related complications was 60.5% in patients with transfusion-dependent thalassemia (TDT) and 43% in patients with non-transfusion-dependent thalassemia (NTDT). Splenectomy was statistically associated with complications in both TDT and NTDT patients (adjusted odds ratio (AOR) = 7.4, p-value = 0.0001 and AOR = 2.6, p-value = 0.001). Age ≥50 years old (AOR = 2.9, p-value = 0.04) and female gender (AOR = 0.5, p-value = 0.03) were statistically associated with the complications in patients with NTDT.

CONCLUSION

Nearly half of the patients in this cohort had disease-related complications. Splenectomy and advanced age were important factors for complication involvement. Early screening for the complications may reduce the morbidity and mortality in patients with thalassemia.

A Clinical Risk Score for Predicting Paraspinal Extramedullary Hematopoiesis in Patients with Thalassemia: The KKU-EMH Score

BACKGROUND

Paraspinal extramedullary hematopoiesis (EMH) is uncommon, but it is one of major complications of increased morbidity in patients with thalassemia.

OBJECTIVE

To develop a clinical risk score for predicting paraspinal extramedullary hematopoiesis in patients with thalassemia.

MATERIAL AND METHOD

A retrospective study was conducted in adult patients with thalassemia at Srinagarind Hospital, Khon Kaen University (KKU) and Udonthani Hospital, Thailand. Paraspinal EMH was defined as radiologic evidence of EMH foci with or without symptoms. The clinical parameters significantly associated with EMH were entered into the logistic regression model. The risk score was derived from the final model’s coefficients. A receiver-operating characteristic (ROC) curve was constructed to determine the area under the ROC curve and the cut-off point.

RESULTS

The KKU-EMH score included: 1) age greater than 25 year (2 points) and 2) thalassemic facie (3 points). Using the cut-off of 5 points, the score showed good discrimination with an area under the ROC curve of 0.83 (95% CI 0.76 to 0.90).

CONCLUSION

Advanced age and thalassemic facie are independent risk factors for paraspinal EMH in patients with thalassemia. The KKU-EMH score is a practical score. It can be used as a screening tool for paraspinal EMH in patients with β-thalassemia.

Severe bacterial infections in patients with non-transfusion-dependent thalassemia: prevalence and clinical risk factors

INTRODUCTION

Bacterial infection is one of the major causes of death in patients with thalassemia. Clinical predictive factors for severe bacterial infection were evaluated in patients with non-transfusion-dependent thalassemia (NTDT).

METHODS

A retrospective study was conducted of patients with NTDT aged ≥ 10 years at Srinagarind Hospital, Khon Kaen University, Thailand. Clinical characteristics and potential clinical risk factors for bacterial infection were collected. Risk factors for bacterial infection were evaluated by multivariate logistic regression analysis.

RESULTS

A severe bacterial infection was found in 11 of the total 211 patients with NTDT (5.2%). None of the clinical factors assessed was shown to be statistically associated with severe bacterial infection in patients with NTDT. However, three factors were demonstrated to be potential predictive factors for severe bacterial infection: time after splenectomy >10 years, deferoxamine therapy, and serum ferritin >1000 ng/ml. None of the patients died from infection.

CONCLUSION

The prevalence of bacterial infection in patients with NTDT was found to be moderate. Time after splenectomy >10 years, deferoxamine therapy, and iron overload may be clinical risk factors for severe bacterial infection in patients with NTDT. Bacterial infection should be recognized in splenectomized patients with NTDT, particularly those who have an iron overload.

Phenotype and Genotype in a Cohort of 312 Adult Patients with Nontransfusion-Dependent Thalassemia in Northeast Thailand

Patients with nontransfusion-dependent thalassemia (NTDT) do not require regular blood transfusion for survival but may encounter several complications that contribute to morbidity and mortality. We report the molecular heterogeneity and hematological features of NTDT in 312 adult patients in northeast Thailand. Hemoglobin (Hb) and DNA analyses identified 177 subjects with Hb E-β-thalassemia, 1 with homozygous β0-thalassemia and 134 with Hb H, AEBart's and EEBart's diseases. For β-thalassemia, 12 different mutations including both β0- and β+-thalassemias were detected. Coinheritance of α-thalassemia as an ameliorating factor was observed in 18 of 178 cases (10.1%) with β-thalassemia. The α-globin gene triplicated haplotype (αααanti3.7) was observed in 1 case of Hb E-β0-thalassemia. The presence of the -158 (Cx2192;T) Gx03B3;-XmnI polymorphism (+/+) was found to be associated with increased Hb F expression, but its frequency in the studied subjects was low. Those with α-thalassemia included 17 with deletional and 51 nondeletional Hb H, and 63 with AEBart's and 3 with EEBart's diseases. The hematological parameters of these NTDT and genotype-phenotype relationships are presented. The diverse molecular heterogeneity of NTDT underlines the importance of complete genotyping of the patient. These results should prove useful for management planning, the prediction of clinical outcome and to improve genetic counseling for NTDT patients.

Effect of genotype on pulmonary hypertension risk in patients with thalassemia

INTRODUCTION

Pulmonary hypertension is one of the major complications in patients with non-transfusion-dependent thalassemia (NTDT). Patients with NTDT have distinct genetic subgroups. Therefore, the effects of different genotype groups on pulmonary hypertension risk in patients with NTDT were assessed.

METHODS

A cross-sectional study was conducted in patients with NTDT aged ≥ 10 yr old at Srinagarind University Hospital and Udonthani Hospital, Thailand. Pulmonary hypertension risk was defined as peak tricuspid regurgitation velocity > 2.9 m/s by trans-thoracic echocardiography. Clinical characteristics and laboratory data that literature has indicated as risk factors for pulmonary hypertension were collected. The effect of genotype group on pulmonary hypertension risk was evaluated by using multivariate logistic regression analysis.

RESULTS

Of 219 patients, pulmonary hypertension risk was found in 24 patients (10.96%). All patients were categorized into two groups according to genetic data that included: (i) β-thalassemia (139, 63.5%), (ii) α-thalassemia and combined α and β-thalassemia (80, 36.5%). Genotype groups were statistically and significantly associated with pulmonary hypertension risk based on the adjusted odds ratios after adjustment for other factors. Patients with β-thalassemia had a statistically significant higher risk for pulmonary hypertension risk (odds ratio = 9.47, P = 0.036) compared to patients with α-thalassemia and patients with combined α and β-thalassemia.

CONCLUSION

The genotype group is an independent risk factor for pulmonary hypertension in patients with NTDT. Echocardiography should be routinely recommended for all patients with β-thalassemia. Routine screening in patients with α-thalassemia and combined α and β-thalassemia, however, may not be necessary or should focus on the older population.

Clinical characteristics and treatment outcomes in patients with Helicobacter pylori-positive chronic immune thrombocytopenic purpura

Immune thrombocytopenic purpura (ITP) is the condition caused by increased platelet destruction and or decreased platelet production. Previous studies have demonstrated the association and efficacy of Helicobacter pylori (H. pylori) eradication therapy in patients with chronic ITP. Data in Thai patients, however, are limited. A prospective cross-sectional analytic study was conducted in adult patients with chronic ITP to determine the prevalence and clinical predictive factors of H. pylori infection and evaluate the efficacy of H. pylori eradication therapy. H. pylori-infected patients received eradication therapy (omeprazole 40 mg/day, clarithromycin 1000 mg/day, amoxicillin 2000 mg/day) for 2 weeks. The platelet counts at baseline and monthly for 6 months after the end of treatment were evaluated. Of the 25 patients, 9 patients (36%) had H.pylori infection. H. pylori infection is higher among women than men. There were two clinical factors included 1) relapsed ITP 2) response after the first-line treatment statistically proven to be associated with H. pylori infection with an odds ratio and p value of 7.7, p = 0.035 and ND (not determined due to small sample size), p < 0.001. Nearly 80% of infected patients had the platelet count response after eradication therapy with the median time to response of 4 months. The prevalence of H. pylori infection is modest in Thai adult patients with chronic ITP. A history of relapsed ITP and high quality of response after first-line treatment indicated H. pylori infection. Therefore, the urea breath test should be recommended in patients who have a relapsed ITP condition with a history of good response after first-line therapy.

Bone marrow abnormalities in systemic lupus erythematosus with peripheral cytopenia

OBJECTIVES

Peripheral cytopenia is frequently found among patients with systemic lupus erythematosus (SLE). Bone marrow examination is usually considered in most cases; however, the incidence and association between cytopenia and disorders of the bone marrow remain unclear. We therefore conducted a prospective, cross-sectional, analytical study among patients with SLE and peripheral cytopenia to determine the incidence of bone marrow abnormalities and to find predictive factors for bone marrow examination.

RESULTS

Of the 41 patients, 20 had bone marrow abnormalities that could be categorised into six groups: hypocellularity (50%), plasmacytosis (35%), haemophagocytosis (30%), dyserythropoiesis (10%), aplastic marrow (10%) and myelofibrosis (5%). Most of the patients (75.6%) had moderate to severe, active disease and recovery from the cytopenia occurred after treatment of the SLE. None of the clinical factors was statistically proven to be associated with bone marrow abnormalities; however, 3 factors indicated an active disease status including (a) the SLEDAI score (b) the number of organs involved and (c) previous immunosuppressive drug therapy. All of these are potentially predictive factors of bone marrow abnormalities.

CONCLUSIONS

The incidence of bone marrow abnormalities is high among patients with SLE and peripheral cytopenia. Bone marrow may be one of the common targets of organs affected by immune mechanisms in active SLE. Peripheral cytopenia can be subsequently improved after treatment of the disease; therefore, bone marrow examination should be recommended among patients whose cytopenia does not recover after conventional therapy.

The impact and disease burden of thalassemia in Thailand: a population-based study in 2010

BACKGROUND

Thalassemia is a common genetic disease in Thailand. However, current data on the impact and disease burden of thalassemia in Thailand remains limited.

OBJECTIVE

To determine the admission rate, OPD visit rate, mortality rate, hospital cost, length of hospital stay, blood transfusion rate and major complications rate in patients with thalassemia.

MATERIAL AND METHOD

The present study analyzed the data of inpatients and outpatients with a diagnosis of thalssemia according to ICD10 coded D56, D56.0, D56.1, D56.2, D56.3, D56.4, D56.8 and D56.9 which came from nationwide health financing schemes in the fiscal year 2010.

RESULTS

The overall admission rate and OPD visit rate were 154 and 562 per 100,000 populations and higher in children and adolescents. The overall mortality rate was 1.13 per 100,000 populations. The total healthcare cost was 744,998,997 Baht or US$ 23,486,727 per year. Blood transfusion rate was significantly higher among children and adolescents. The thalassemia-related complications commonly occurred at the second and the third decades of life.

CONCLUSION

The admission rate, OPD visit rate, blood transfusion rate were higher among children and adolescents. The total healthcare cost was high which was nearly 745 million Baht per year. The hospital cost, length of stay and major complications were increased with age.

Disease burden of immune thrombocytopenic purpura among adult patients: the analysis of Thailand healthcare databases 2010

BACKGROUND

Immune thrombocytopenic purpura (ITP) is not rare disease and it ispotentially fatal, particularly in patients with bleeding events which usually lead to hospitalization. Current data on the impact and disease burden of ITP in Thailand are lacking.

OBJECTIVE

To determine admission rate, mortality rate, hospital cost, length of hospital stay, co-morbidities, treatment and major bleeding events in patients with ITP.

MATERIAL AND METHOD

The authors analyzed the data of inpatients with a diagnosis of ITP according to ICD10 coded D69.3 which were retrieved from a nationwide health financing schemes in fiscal 2010. The data were analyzed by age groups, gender and health financing schemes.

RESULTS

The overall admission rate and mortality rate were 7.68 and 0.29 per 100,000 populations, respectively and increased with age. Women were predominant. Average hospital costs and hospital stays were 27,133 Baht and 6.7 days per admission, respectively and slightly higher among men than women. The most common co-morbidity was hypertension. Gastrointestinal hemorrhage was the most common bleeding event which was 21.5 per 1,000 admissions. Patients in the civil servant medical benefit scheme had the highest percentage of high cost treatment accessibility.

CONCLUSION

The admission rate, mortality rate and major bleeding events increased with age and was higher among women than men. Average hospital cost and length of hospital stay are higher in men than women. Common co-morbidities may be related to the treatment of ITP There are the differences in high-cost treatment accessibility between health insurance schemes.

Compound heterozygous Hb Tak/Hb E causes secondary erythrocytosis in a Thai family

Hb Tak is a rare cause of secondary erythrocytosis. It results from the insertion of two nucleotides (AC) at the termination codon between codon 146 and codon 147 of the beta-globin gene. This insertion causes a frameshift in the terminating codon 147 resulting in an elongated beta chain with an impaired formation of the T-state. We report a Thai family with a compound heterozygosity for Hb Tak [beta147 (+ AC)] and Hb E [beta26(B8)Glu-->Lys] which displayed an asymptomatic erythrocytosis.