Kleebsabai Sanpakit

Mutations in Krüppel-like factor 1 cause transfusion-dependent hemolytic anemia and persistence of embryonic globin gene expression

In this study, we report on 8 compound heterozygotes for mutations in the key erythroid transcription factor Krüppel-like factor 1 in patients who presented with severe, transfusion-dependent hemolytic anemia. In most cases, the red cells were hypochromic and microcytic, consistent with abnormalities in hemoglobin synthesis. In addition, in many cases, the red cells resembled those seen in patients with membrane defects or enzymopathies, known as chronic nonspherocytic hemolytic anemia (CNSHA). Analysis of RNA and protein in primary erythroid cells from these individuals provided evidence of abnormal globin synthesis, with persistent expression of fetal hemoglobin and, most remarkably, expression of large quantities of embryonic globins in postnatal life. The red cell membranes were abnormal, most notably expressing reduced amounts of CD44 and, consequently, manifesting the rare In(Lu) blood group. Finally, all tested patients showed abnormally low levels of the red cell enzyme pyruvate kinase, a known cause of CNSHA. These patients define a new type of severe, transfusion-dependent CNSHA caused by mutations in a trans-acting factor (Krüppel-like factor 1) and reveal an important pathway regulating embryonic globin gene expression in adult humans.

Hematopoietic stem cell transplantation for homozygous β-thalassemia and β-thalassemia/hemoglobin E patients from haploidentical donors

Thalassemia-free survival after allogeneic stem cell transplantation (SCT) is about 80–90% with either matched-related or -unrelated donors. We explored the use of a mismatched-related (‘haplo- ’) donor. All patients received two courses of pretransplant immunosuppressive therapy (PTIS) with fludarabine (Flu) and dexamethasone (Dxm). After two courses of PTIS, a conditioning regimen of rabbit antithymocyte globulin, Flu and IV busulfan (Bu) was given followed by T-cell-replete peripheral blood progenitor cells. GvHD prophylaxis consisted of cyclophosphamide (Cy) on days SCT +3 and +4 (post-Cy), and on day SCT +5 tacrolimus or sirolimus was started together with a short course of mycophenolate mofetil. Thirty-one patients underwent haplo-SCT. Their median age was 10 years (range, 2–20 years). Twenty-nine patients engrafted with 100% donor chimerism. Two patients suffered primary graft failure. Median time to neutrophil engraftment was 14 days (range, 11–18 days). Five patients developed mild to moderate, reversible veno-occlusive disease, while nine patients developed acute GvHD grade II. Only five patients developed limited-chronic GvHD. Projected overall and event-free survival rates at 2 years are 95% and 94%, respectively. The median follow up time is 12 months (range, 7–33 months).

Homozygous hemoglobin Tak causes symptomatic secondary polycythemia in a Thai boy.

Secondary polycythemia caused by high-oxygen-affinity hemoglobin is rare in children. Most patients with this condition have asymptomatic erythrocytosis. In this article the authors describe a young boy from Thailand with plethora, hypoxemia, and aggravated respiratory distress following a chest infection. Hematological and molecular studies revealed that the boy is homozygous for Hb Tak, an extended &bgr;-globin variant with high oxygen affinity. This report of a patient who is homozygous for high-oxygen-affinity hemoglobin highlights the clinical significance of this hemoglobin disorder, which has been previously reported in several unrelated families from Southeast Asia.

Allogeneic stem cell transplantation for children with acquired severe aplastic anaemia: a retrospective study by the Viva-Asia Blood and Marrow Transplantation Group

We retrospectively analysed the outcomes of 127 children with acquired severe aplastic anaemia (SAA) who had received haematopoietic stem cell transplantation (HSCT) between 2000 and 2011 in one of the 10 Asia Pacific institutions. Fifty‐three were matched sibling donor (MSD) and 74 were alternative donor (AD), including 22 matched unrelated donor, 32 mismatched unrelated donor and 20 mismatched related donor. With a median follow up 45·5 months (13–139) and when compared to the MSD group, AD recipients had more grade II‐IV acute graft‐versus‐host disease (aGVHD; 14·3% vs. 32·8%, P = 0·029), but similar grade III‐IV aGVHD (10·2% vs. 12·5%, P = 0·774), graft failure (GF) (15·1% vs. 15·5%, P = 0·658) and 5‐year overall survival (90·6% vs. 83·7%, P = 0·251). As a source of stem cell, peripheral blood stem cells (PBSC) resulted in less GF (18% vs. 9·1% P = 0·013), similar grade II‐IV aGVHD (28·1% vs. 17·4%, P = 0·258), chronic GVHD (25·8% vs. 29·3%, P = 0·822) and similar outcomes (89·7% vs. 82·4%, P =0 ·665) when compared to bone marrow (BM). In univariate analysis, GF (P < 0·001) and grade II‐IV aGVHD (P = 0·009) were predictors of poor survival. In multivariate analysis, only GF was associated with poor survival (P = 0·012). The outcome of AD and PBSC HSCT were comparable to that of MSD and BM HSCT in the Asia Pacific region.

Outcomes of Thalassemia Patients Undergoing Hematopoietic Stem Cell Transplantation by Using a Standard Myeloablative versus a Novel Reduced-Toxicity Conditioning Regimen According to a New Risk Stratification

Improving outcomes among class 3 thalassemia patients receiving allogeneic hematopoietic stem cell transplantations (HSCT) remains a challenge. Before HSCT, patients who were ≥ 7 years old and had a liver size ≥ 5 cm constitute what the Center for International Blood and Marrow Transplant Research defined as a very high-risk subset of a conventional high-risk class 3 group (here referred to as class 3 HR). We performed HSCT in 98 patients with related and unrelated donor stem cells. Seventy-six of the patients with age < 10 years received the more conventional myeloablative conditioning (MAC) regimen (cyclophosphamide, busulfan, ± fludarabine); the remaining 22 patients with age ≥ 10 years and hepatomegaly (class 3 HR), and in several instances additional comorbidity problems, underwent HSCT with a novel reduced-toxicity conditioning (RTC) regimen (fludarabine and busulfan). We then compared the outcomes between these 2 groups (MAC versus RTC). Event-free survival (86% versus 90%) and overall survival (95% versus 90%) were not significantly different between the respective groups; however, there was a higher incidence of serious treatment-related complications in the MAC group, and although we experienced 6 graft failures in the MAC group (8%), there were none in the RTC group. Based on these results, we suggest that (1) class 3 HR thalassemia patients can safely receive HSCT with our novel RTC regimen and achieve the same excellent outcome as low/standard-risk thalassemia patients who received the standard MAC regimen, and further, (2) that this novel RTC approach should be tested in the low/standard-risk patient population.

Cushing’s syndrome caused by an ACTH-producing ovarian steroid cell tumor, NOS, in a prepubertal girl

Ectopic ACTH syndrome is a very rare cause of pediatric Cushing’s syndrome. And if present, bronchial or thymic carcinoids predominate as causes. We hereby demonstrate a first case report of ACTH-producing ovarian steroid cell tumor, NOS, causing ectopic ACTH syndrome in a prepubertal girl.

Prognostic factors and treatment outcomes of retinoblastoma in pediatric patients: a single-institution study

PurposeSince 1997, our institute has used neoadjuvant chemotherapy for intraocular retinoblastoma. However, some of the patients showed signs of recurrence months to years later. We therefore attempted to determine the prognostic factors of treatment outcomes and survival in our patients.MethodsWe reviewed 90 patients treated from 1997 to 2006. The following information was recorded: demographic and ophthalmological data, clinical classification, histopathological data, and treatment methods and outcomes.ResultsEnucleation was avoided in two of 57 eyes in the unilateral group. Sixteen of 54 eyes in the bilateral group were salvaged by systemic chemotherapy with local treatment. There was no difference in histopathological findings between the two groups. Nine of 57 patients in the unilateral group demonstrated poor outcomes, compared with four of 27 in the bilateral group. Significant poor prognostic factors for survival were optic nerve head invasion, orbital involvement, abnormal results on bone marrow aspiration, lumbar puncture, bone scan, and group E or F classification.ConclusionsThe 15% mortality rate in our patients is slightly higher than that reported in developed countries. Delayed diagnosis and treatment is the main cause of avoidable deaths. Improving education of both clinicians and parents would increase survival rates in this potentially fatal disease.

Intersite validations of the pixel-wise method for liver R2* analysis in transfusion-dependent thalassemia patients: a more accessible and affordable diagnostic technology

BACKGROUND AND OBJECTIVES MRI-R2* has been accepted as a clinical tool for monitoring iron overload in thalassemia patients, especially for monitoring liver iron concentration (LIC). The most optimal and practical method of analysis however, is still open to further investigations. Our objective was to investigate intra- and intersite observer variability of the pixel-wise method for liver R2* analysis in thalassemia patients using a mono-exponential with a constant offset model. PATIENTS AND METHODS We performed 88 liver R2* measurements on 72 thalassemia major patients. A single breath-hold multi-echo gradient-echo sequence was acquired and analyzed at both the reference (REF) and local (LOC) sites. The analysis defined the region of interest in the whole liver parenchyma, excluding the great vessels, and were reported as median values. RESULTS The R2* values from the REF and LOC were statistically comparable for all comparisons. The intrasite and intersite observer variation were 0.75% (less than 0.9%) and 2.5%, respectively, both of which are comparable to previous reports, but substantially lower than conventional region-based approaches. CONCLUSION The low variation of the R2* also yielded excellent variation in the tabulated hepatic iron content. However, caution is required when comparing the results to different implementation methods and appropriate evaluation and validation of methodology for any new scan site is essential before its clinical use.

Acute haemolytic crisis in a Thai patient with homozygous haemoglobin Constant Spring (Hb CS/CS): a case report.

Abstract Acute haemolysis associated with mild upper respiratory tract infection was observed in a Thai boy who presented with a rapid decline in haemoglobin (Hb) levels, haemoglobinuria and evidence of intravascular haemolysis. Several possible causes giving rise to such a condition were excluded including G6PD deficiency, which is extremely common in Thailand. Subsequent haematological and molecular analyses demonstrated that the patient was homozygous for Hb Constant Spring (Hb CS/CS), an a globin haemoglobinopathy. It has been shown previously that patients with homozygous Hb CS had mild haemolytic anaemia secondary to an accumulation of a CS chains, which are toxic to red blood cell membrane cytoskeletons. Increased body temperature might induce more precipitation of this a globin variant. This report highlights the importance of Hb CS/CS as a potential predisposing cause of acute haemolysis in children that might be aggravated by acute bacterial or viral infections. This is particularly relevant for patients of Southeast Asian descent where this abnormal haemoglobin is highly prevalent.

Long-term outcome in pediatric renal tumor survivors: experience of a single center.

Medical records of 30 children with renal tumor diagnosed at Siriraj Hospital during 1996 to 2007 were reviewed. Mean age at diagnosis was 36 months; male to female ratio was 1.7:1. Clinical manifestations included abdominal mass (96.7%), hypertension (40.0%), abdominal pain (36.7%), hematuria (26.7%), postrenal obstruction (16.7%), and proteinuria (13.3%). Eight patients had Denys-Drash malformations, WAGR, Dandy-Walker malformation, or genitourinary anomalies. Twenty-seven patients (90%) had Wilms tumor. Sixteen patients were stage 3 or more at diagnosis. Rhabdoid tumor was found in 3 patients. All patients received chemotherapy, 13 patients also received radiation therapy. Acute complications included febrile neutropenia (44.4%), hypokalemia (37.0%), hyponatremia (29.6%), Fanconi syndrome (11.1%), urinary tract Infection (10.0%), and acute renal failure (7.4%). Mean follow-up time was 57.2 months. Ten patients died from progressive disease. Five-year patient survival was 69.7%. Two patients had chronic kidney disease. One of these had Denys-Drash malformations. Both patients received ifosfamide-carboplatin-etoposide protocol and abdominal radiation. Antihypertensive medications were needed in 9 patients for a mean duration of 164 days. None had persistent proteinuria or hematuria. No difference was found among mean estimated glomerular filtration rate at diagnosis, 1 year after treatment, and at last follow-up. Long-term follow-up, especially renal function, is recommended.