Adisak Tantiworawit

First Isolation of Leishmania from Northern Thailand: Case Report, Identification as Leishmania martiniquensis and Phylogenetic Position within the Leishmania enriettii Complex

Since 1996, there have been several case reports of autochthonous visceral leishmaniasis in Thailand. Here we report a case in a 52-year-old Thai male from northern Thailand, who presented with subacute fever, huge splenomegaly and pancytopenia. Bone marrow aspiration revealed numerous amastigotes within macrophages. Isolation of Leishmania LSCM1 into culture and DNA sequence analysis (ribosomal RNA ITS-1 and large subunit of RNA polymerase II) revealed the parasites to be members of the Leishmania enriettii complex, and apparently identical to L. martiniquensis previously reported from the Caribbean island of Martinique. This is the first report of visceral leishmaniasis caused by L. martiniquensis from the region. Moreover, the majority of parasites previously identified as “L. siamensis” also appear to be L. martiniquensis.

Heart rate variability in beta-thalassemia patients.

Background:  Cardiac failure remains the major cause of death in beta‐thalassemia major (TM). Reduced heart rate variability (HRV) is associated with a higher risk of arrhythmias after myocardial infarction and heart failure. We evaluated HRV in TM patients and its relationship with hemodynamics and echocardiographic parameters during a 6‐month follow‐up.

Heart Rate Variability as an Alternative Indicator for Identifying Cardiac Iron Status in Non-Transfusion Dependent Thalassemia Patients.

Background Iron-overload cardiomyopathy is a major cause of death in thalassemia patients due to the lack of an early detection strategy. Although cardiac magnetic resonance (CMR) T2* is used for early detection of cardiac iron accumulation, its availability is limited. Heart rate variability (HRV) has been used to evaluate cardiac autonomic function and found to be depressed in thalassemia. However, its direct correlation with cardiac iron accumulation has never been investigated. We investigated whether HRV can be used as an alternative indicator for early identification of cardiac iron deposition in thalassemia patients. Methods Ninety-nine non-transfusion dependent thalassemia patients (23.00 (17.00, 32.75) years, 35 male) were enrolled. The correlation between HRV recorded using 24-hour Holter monitoring and non-transferrin bound iron (NTBI), hemoglobin (Hb), serum ferritin, LV ejection fraction (LVEF), and CMR-T2* were determined. Results The median NTBI value was 3.15 (1.11, 6.59) μM. Both time and frequency domains of HRV showed a significant correlation with the NTBI level, supporting HRV as a marker of iron overload. Moreover, the LF/HF ratio showed a significant correlation with CMR-T2* with the receiver operating characteristic (ROC) curve of 0.684±0.063, suggesting that it could represent the cardiac iron deposit in thalassemia patients. HRV was also significantly correlated with serum ferritin and Hb. Conclusions This novel finding regarding the correlation between HRV and CMR-T2* indicates that HRV could be a potential marker in identifying early cardiac iron deposition prior to the development of LV dysfunction, and may be used as an alternative to CMR-T2* for screening cardiac iron status in thalassemia patients.

Clinical Manifestations and Risk Factors for Complications of Philadelphia Chromosome-Negative Myeloproliferative Neoplasms

BACKGROUND Myeloproliferative neoplasms (MPNs) are clonal hematopoietic stem cell disorders characterized by proliferation of one or more myeloid lineages. Polycythemia vera (PV), essential thrombocythemia (ET) and primary myelofibrosis (PMF) are classical Philadelphia chromosome (Ph)-negative MPN that have a Janus Kinase 2 (JAK2) mutation, especially JAK2V617F in the majority of patients. The major complications of Ph-negative MPNs are thrombosis, hemorrhage, and leukemic transformation. OBJECTIVE To study clinical manifestations including symptoms, signs, laboratory findings, and JAK2V617F mutations of Ph-negative MPN (PV, ET and PMF) as well as their complications. MATERIALS AND METHODS All Ph-negative MPN (PV, ET and PMF) patients who attended the Hematology Clinic at Maharaj Nakorn Chiang Mai Hospital from January, 1 2003 through December, 31 2013 were retrospectively reviewed for demographic data, clinical characteristics, complete blood count, JAK2V617F mutation analysis, treatment, and complications. RESULTS One hundred and fifty seven patients were included in the study. They were classified as PV, ET and PMF for 68, 83 and 6 with median ages of 60, 61, and 68 years, respectively. JAK2V617F mutations were detected in 88%, 69%, and 100% of PV, ET and PMF patients. PV had the highest incidence of thrombosis (PV 29%, ET 14%, and PMF 0%) that occurred in both arterial and venous sites whereas PMF had the highest incidence of bleeding (PMF 17%, ET 11%, and PV 7%). During follow up, there was one ET patient that transformed to acute leukemia and five cases that developed thrombosis (three ET and two PV patients). No secondary myelofibrosis and death cases were encountered. CONCLUSIONS Ph-negative MPNs have various clinical manifestations. JAK2V617F mutations are present in the majority of PV, ET, and PMF patients. This study confirmed that thrombosis and bleeding are the most significant complications in patients with Ph-negative MPN.

Chronic generalized fibrotic skin lesions from disseminated leishmaniasis caused by Leishmania martiniquensis in two patients from northern Thailand infected with HIV

Leishmaniasis is a newly emerging infection in Thailand. Most of the previous human cases have presented with the clinical features of visceral leishmaniasis and were mainly found in southern Thailand. Here we report the first two patients from northern Thailand presenting with disseminated cutaneous leishmaniasis.

Heart Rate Variability for Early Detection of Iron Overload Cardiomyopathy in β-Thalassemia Patients

Abstract Iron overload cardiomyopathy remains the major cause of death in β-thalassemia (β-thal). Conventional routine screening parameters such as serum ferritin and echocardiogram (ECG) do not permit early detection of this condition. Although non-transferrin-bound iron (NTBI) is a reliable indicator for iron overload, it is still not universally available. Recently, heart rate variability (HRV), representing cardiac autonomic function, was found to be depressed in thalassemia patients. We hypothesized that HRV can be used for early detection of iron overload cardiomyopathy. Fifty patients (aged 29 ± 11 years; 31 females and 19 males) with β-thal were enrolled. The 24-hour Holter monitoring for HRV, serum ferritin, NTBI, hematological values and ECG were performed for each patient. Of the 50 patients, 29 carried β-thal major (β-TM). Non-transferrin-bound iron was weakly correlated to all time-domain HRV parameters. Low- and high-frequency domain HRV parameters were also inversely weakly correlated with NTBI. Neither HRV nor NTBI was correlated with serum ferritin. With its weak but significant correlation with NTBI, HRV may be considered to be used as a potential indicator of an iron overload condition and an early marker of cardiac involvement in patients with β-thal.

Heart Rate Variability for Early Detection of Cardiac Iron Deposition in Patients with Transfusion-Dependent Thalassemia

Background Iron overload cardiomyopathy remains the major cause of death in patients with transfusion-dependent thalassemia. Cardiac T2* magnetic resonance imaging is costly yet effective in detecting cardiac iron accumulation in the heart. Heart rate variability (HRV) has been used to evaluate cardiac autonomic function and is depressed in cases of thalassemia. We evaluated whether HRV could be used as an indicator for early identification of cardiac iron deposition. Methods One hundred and one patients with transfusion-dependent thalassemia were enrolled in this study. The correlation between recorded HRV and hemoglobin, non-transferrin bound iron (NTBI), serum ferritin and cardiac T2* were evaluated. Results The median age was 18 years (range 8–59 years). The patient group with a 5-year mean serum ferritin >5,000 ng/mL included significantly more homozygous β-thalassemia and splenectomized patients, had lower hemoglobin levels, and had more cardiac iron deposit than all other groups. Anemia strongly influenced all domains of HRV. After adjusting for anemia, neither serum ferritin nor NTBI impacted the HRV. However cardiac T2* was an independent predictor of HRV, even after adjusting for anemia. For receiver operative characteristic (ROC) curve analysis of cardiac T2* ≤20 ms, only mean ferritin in the last 12 months and the average of the standard deviation of all R-R intervals for all five-minute segments in the 24-hour recording were predictors for cardiac T2* ≤20 ms, with area under the ROC curve of 0.961 (p<0.0001) and 0.701 (p = 0.05), respectively. Conclusions Hemoglobin and cardiac T2* as significant predictors for HRV indicate that anemia and cardiac iron deposition result in cardiac autonomic imbalance. The mean ferritin in the last 12 months could be useful as the best indicator for further evaluation of cardiac risk. The ability of serum ferritin to predict cardiac risk is stronger than observed in other thalassemia cohorts. HRV might be a stronger predictor of cardiac iron in study populations with lower somatic iron burdens and greater prevalence of cardiac iron deposition.

Pulmonary hypertension in non-transfusion-dependent thalassemia: Correlation with clinical parameters, liver iron concentration, and non-transferrin-bound iron

Abstract Background Pulmonary hypertension is a major cardiac complication in non-transfusion-dependent thalassemia (NTDT). Several clinical and laboratory parameters, including iron overload, have been shown to have a positive correlation with the incidence of pulmonary hypertension. Non-transferrin-bound iron (NTBI) is a form of free-plasma iron that is a good indicator of iron overload. Objectives The aim of this study was to determine the prevalence of pulmonary hypertension in patients with NTDT and to investigate its correlation with the clinical parameters, liver iron concentration (LIC) and NTBI. Methods Patients with NTDT were evaluated using echocardiography, and magnetic resonance imaging for cardiac T2* and LIC. Pulmonary hypertension was defined as peak tricuspid regurgitation velocity ≥2.9 m/s measured using trans-thoracic echocardiography. Clinical parameters and the status of iron overload as determined by LIC, serum ferritin, and NTBI level were evaluated for their association with pulmonary hypertension. Results Of 76 NTDT patients, mean age 23.7 ± 8.5 years, seven patients (9.2%) had pulmonary hypertension. Previous splenectomy (71.4 vs. 24.6%, P-value 0.019), higher cumulative red blood cell (RBC) transfusions (received ≥10 RBC transfusions 85.7 vs. 33.3%, P-value 0.011), higher nucleated RBCs (353 ± 287 vs. 63 ± 160/100 white blood cells, P-value <0.001), and a high NTBI level (5.7 ± 3.0 vs. 3.3 ± 2.8 µmol/l, P-value 0.034) were associated with pulmonary hypertension. There was no significant correlation between LIC or serum ferritin and pulmonary hypertension. Conclusion Pulmonary hypertension in NTDT is common, and is associated with splenectomy and its related factors. NTBI level shows a significant correlation with pulmonary hypertension.

Clinical characteristics and long-term outcomes of warm-type autoimmune hemolytic anemia

Objectives: To study the clinical manifestations, outcomes, and survival of warm-type autoimmune hemolytic anemia (AIHA) patients. Methods: This study was a retrospective single-center study from 2002 to 2013. Clinical data of AIHA patients were reviewed and analyzed. Results: One hundred and one patients were included, of whom 77% were female with a median age of 43 years. Primary AIHA was found in 61% of the patients. The secondary causes were systemic lupus erythematosus (SLE) (64%), solid malignancies (13%), lymphomas (10%), drugs (8%), and infections (5%). Most patients (96%) responded to steroids, which were not different between primary and secondary AIHA. Second-line treatments were required in 33 patients (33%). The indications were steroid dependence (58%), relapse (30%), and others (12%). The most common second-line treatment was cyclophosphamide (52%). The response rate for second-line treatments was 93%. Relapse occurred in 50 patients (50%) in which 58% occurred more than 3 years after diagnosis. The SLE patients relapsed and received second-line therapy more than the non-SLE group (P < 0.001). At the median 53-month follow-up, the overall survival (OS) was 84%. The independent risk factors for OS were age more than 50 years and malignancy. Sepsis was the most common cause of death. Discussion and conclusion: AIHA has a good prognosis and long-term survival especially in young patients without malignancy. Most patients have responded initially to steroids and have a high response rate to second-line therapy. Carefully adjusted and rapid taper of immunosuppressant is necessary to avoid sepsis complications.

High Induction Response Rate, but Poor Long-Term Disease Free Survival in Elderly Patients Treated Aggressively for Acute Lymphoblastic Leukemia

Elderly Acute Lymphoblastic Leukemia (ALL) patients are routinely offered palliative chemotherapy and best supportive care. Few studies have addressed their outcome with aggressive chemotherapy. We pursued this population based study to address the outcome of ALL patients older than 60 years treated with aggressive chemotherapy. We reviewed 32 consecutive patients treated with aggressive chemotherapy between 1989 and 2008. Twenty-seven patients (84.4%) achieved Complete Remission (CR) to induction chemotherapy of whom 23 patients (85.2%) had disease relapse. Median time to relapse was 8 (3.7-44) months. Median disease free survival and overall survival were 10.4 (0-43.9) and 16.3 (1.3-59) months, respectively. Cause of death was disease progression in 25/27 (92.6%). Seven patients (21.8%) had Philadelphia chromosome positive (Ph+) disease. Six out of these seven patients received combination chemotherapy with a tyrosine kinase inhibitor. The 3-year overall survival for the whole group was 26%; 36% for Ph+ and 23% Ph- patients. Despite the high CR rate, relapse remains inevitable and most patients died secondary to relapse. Prospective randomized studies are needed to identify the role of reduced intensity stem cell transplantation or other consolidation therapy for this dreadful disease in this age group.