Centrifugation of blood samples to produce platelet-poor plasma is one of the important steps for coagulation testing. Reduction of the time required for specimen processing without affecting quality of results should be ideal for tests which require immediate results. Centrifugation of platelet-poor plasma (3580 rpm) for 15 minutes performed for routine coagulation tests would prolong the turn-around time for an urgent test (30 minutes). This study was done to determine the effect of reducing centrifugation time for routine coagulation tests in order to meet the turn-around time (TAT) for urgent tests. Seventy-nine blood samples sent for routine coagulation tests, were assayed for prothrombin time (PT), activated partial thromboplastin time (APTT), fibrinogen level and platelet counts, using two different centrifugation speed for plasma preparation: centrifugation at 3580 rpm for 15 minutes and rapid centrifugation at 4000 rpm for five minutes. Paired sample t-test showed that there was a significant
difference in the platelet count between the two groups (p=0.001). However, there was no significant difference in the normal APTT (p=0.16), abnormal APTT (p=0.80), abnormal PT (p=0.43) and the results of fibrinogen levels (p=0.36). In conclusion, rapid centrifugation at 4000 rpm for five minutes does not modify results of routine coagulation tests (PT, APTT and fibrinogen). It would be beneficial in providing rapid results for urgent coagulation tests.
Hemoglobin S (HbS, α2β26GluVal) merupakan variasi hemoglobin yang terbentuk hasil daripada mutasi GAG GTG pada kodon 6 gen β-globin. Hemoglobinopati haemoglobin S (HbS) jarang ditemui di kalangan penduduk Malaysia tetapi selalunya dijumpai di kalangan pendatang asing dari Afrika. Walau bagaimanapun beberapa kes didapati dalam kaum India dan Melayu. Kajian ini meninjau keputusan makmal pesakit HbS dan penggunaan “multiplex ligation-dependent probe amplification” (MLPA) dan “flow-through hybridization” (FTH) dalam mengesan mutasi HbS. HbS dikenalpasti melalui kromatografi cecair prestasi tinggi (HPLC) dan/atau elektroforesis kapilari serta elektroforesis hemoglobin. Analisis molekul dijalankan menggunakan kaedah MLPA, FTH dan penjujukan Sanger. Dua warga Afrika, tiga Melayu dan dua India berusia antara 2-31 tahun telah dikenalpasti. Lima pesakit adalah HbS homozigot, seorang kompaun heterozigot HbS/β-talasemia dan seorang lagi pembawa HbS. Tahap hemoglobin (Hb) kes HbS homozigot adalah antara 7.4-10.2 g/dL dengan aras HbS dan HbF diantara 58.3-94.7% dan 1.5-35.5%. Hb untuk kes kompaun heterozigot HbS/β-talasemia adalah 5.8 g/dL dan normal pada pembawa HbS. Aras HbS, HbF dan HbA2 untuk HbS/β-talasemia dan pembawa HbS adalah 67%, 27.2% dan 4.2%, dan 38.6%, 0.1% and 2.8% setiap satu. Kedua-dua kaedah MLPA dan FTH berjaya mengesan mutasi HbS dalam semua kes, manakala cuma FTH dapat menentukan zygositi mutasi HbS dan β-talasemia dalam satu ujian yang sama.
Leukaemic stem cells have heterogenous differentiation potential. The immunophenotypes of blast cells are usually consistent throughout the disease course even at relapse. Rarely, blast cells may undergo a ‘lineage switch’ during the course of disease especially during relapse. We would like to highlight such a case in a 10- year old boy who presented with a two weeks history of lethargy, poor appetite, low grade fever, respiratory distress, cardiac failure, generalized oedema and hepatosplenomegaly. Full blood count showed a leucocyte count of 41.5x10 9 /L and platelet count of 37x10 9 /L. The peripheral blood film showed presence of numerous blast cells. Bone marrow aspiration revealed a hypercellular marrow, which consisted of mainly blast cells with high nuclear to cytoplasmic ratio and inconspicuous nucleoli. Immunophenotyping and cytochemistry results were consistent with the diagnosis of Tcell acute lymphoblastic leukaemia. The patient achieved remission after treatment with UK ALL 97 protocol, regime B chemotherapy. However, he relapsed seven months after the initial diagnosis with 26% blast cells in the bone marrow aspirate. The majority was L1 blast cells admixed with some L2 blast cells. Immunophenotyping was consistent with common precursor B acute lymphoblastic leukaemia. The treatment was changed to a more lineage specific chemotherapy. Nonetheless, the patient never achieved remission and was planned for palliative management. This case illustrated a unique and rare case of rapid lineage switch from T-cell acute lymphoblastic leukaemia to common precursor B-cell acute lymphoblastic leukaemia.
Residual disease in patients with acute leukaemia indicates unfavorable prognosis. The evaluation of remission using flow cytometry allows a better estimation of minimal residual disease (MRD) after induction chemotherapy in childhood acute lymphoblastic leukaemia (ALL) cases. Patients in morphological marrow remission with presence of blast cells of less than 5%, may still have up to 1010 leukaemic cells. However with flow cytometric analysis, lower levels of the residual leukaemic cells (1 in 104 cells) can be detected and it can be used as a tool to predict relapse. This study compared the presenting clinical and haematological features of children with ALL and their residual disease status determined by flow cytometry. Analysis of their MRD status following remission-induction chemotherapy were done at day-28, week-12 and week-20. The cases were also followed up to five years, to determine their survival status. Their residual disease status by flow cytometric immunophenotyping was also compared with their bone marrow findings morphologically. Thirty-eight cases of precursor B-ALL in pediatric patients from UKM Medical Centre (UKMMC) were analyzed. There was no significant correlation between demographic, clinical and haematological features with MRD status at day-28. However, there was a significant correlation between MRD status by flow cytometry and by morphological marrow examination at week-12. Three cases showed persistent MRD findings until week-20 where two of the cases relapsed and died subsequently. Twenty four patients were still alive after five years of follow up.
Acute myeloid leukaemia (AML) is the most common subtype of acute leukaemias with a poor outcome. Msi2 protein is a newly discovered prognostic marker and it has been considered as a new target for therapy in AML. The study of Msi2
protein expression in AML cases has not been performed in Malaysia, to date. The main aim of the present study was to observe the expression of Msi2 protein in AML patients by immunohistochemistry (IHC) and to correlate its expression
with the well-established prognostic and clinical parameters in AML as well as the overall survival (OS). Sixty four bone marrow trephine biopsy sections were immunostained for Msi2 protein. The percentage of blasts with positive reaction
and the intensity of the cytoplasmic and nuclear staining were evaluated. The expression of Msi2 protein was found in 95.3% cases with Msi2 pattern varying between the cases. In 71.9% of cases, the blasts showed total cellular positivity and 23.4% cases showed only cytoplasmic positivity. Majority showed high expression of Msi2 for cytoplasmic staining. Interestingly, there was significant correlation between total cellular staining and the intermediate cytogenetic subgroup (P=0.04). In conclusion, the results showed that the majority of the patients had high expression of Msi2 but this did not correlate to OS. However, the Msi2 expression correlated to the cytogenetic findings. The results suggest future extensive research to be conducted in order to ascertain the exact role of Msi2 positive blast cells in AML in our population and their association with prognosis and outcome.
Keywords: AML, cytogenetics, immunohistochemistry, Msi2 protein
Chronic myeloid leukemia (CML) patients who have BCR-ABL T315I mutation, usually present in the advance phase of the disease with overall survival (OS) shorter than those without the mutation. This study aimed to determine the prevalence of T315I mutation amongst imatinib mesylate (IM) resistant CML patients and to compare the OS between T315I-mutated and non-T315I-mutated patients. Sixty consecutive CML patients who were treated with IM for at least 18 months and their treatment responses, were recorded. The mutation analysis was done using allele-specific oligonucleotide reverse transcriptase-polymerase chain reaction (RT-PCR) assay followed by direct sequencing technique. Forty-two patients (70%) were found to have IM-resistance. Five out of 42 patients had detectable T315I mutation. Median OS of IM-resistant T315I-mutated patients was 96 months (95% CI:54-138) compared to 84 months (95% CI:48-120) in non T315I-mutated patients, although this was found to be statistically insignificant (p = 0.43). The present study showed a higher prevalence of T315I mutation as compared to a few local studies. Median OS of T315I-mutated patients were observed to be longer than non-T315-mutated patients. Further studies encompassing larger cohort of patients are required to confirm this finding.
We report two cases of biphenotypic acute leukaemia diagnosed in Hospital Universiti Kebangsaan Malaysia (HUKM), their clinical, haematological characteristics and response to chemotherapy. Both patients are middle-aged ladies who presented with hepatosplenomegaly and high white cell count, mainly composed of blast cells. Their bone marrow aspirations were hypercellular comprising of more than 90% heterogenous blast cells. Cytochemical analyses show more than 3% positivity towards peroxidase, with smaller blasts showing block positivity towards PAS. Immunophenotypically, the blasts showed dual expression of CD 33 and CD 19, CD 19 and CD34, intra CD22, intra TdT and intraMPO. One of the patients showed presence of the Philadelphia chromosome on cytogenetic analysis which was confirmed by Fluorecsence In Situ Hybridisation (FISH). Molecular analysis also showed presence of the BCR-ABL fusion protein. Both patients were given combination chemotherapy consisting of daunorubicin and cytosine arabinoside.However, the patient with positive Philadelphia chromosome BCR-ABL did not achieve morphological remission after induction chemotherapy. In view of the poor prognosis of this disease, both the patients were planned for upfront peripheral blood stem cell transplantation.
Megakaryoblastic leukaemia is the commonest form of leukaemia occuring in Down syndrome infants. However, it’s subtype with translocation t(1;22)(p13;q13) is uncommon comprising
Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common enzyme deficiency worldwide including Malaysia. Screening of cord blood for partial G6PD deficiency is important as they are also prone to develop acute haemolysis. In this study, we determined the prevalence of partial G6PD deficient in paediatric population aged 1 month-12 years and normal term female neonates using OSMMR-D kit with haemoglobin (Hb) normalization and compare it with florescence spot test (FST). A total of 236 children, aged between between 1 month-12 years and 614 normal term female neonates were recruited for this study. Determination of normal means for G6PD activity and; cut-off points for partial and severe deficiency were determined according to WHO Working Group (1989). Determination of prevalence for partial deficiency for both groups (female patient) was done using this enzyme assay kit and findings were compared with FST. In this study, 15.7% (18/115) female children were classified as partial G6PD deficient by quantitative enzyme method (G6PD activity: 4.23-5.26U/gHb). However, FST only detected 0.9% (1/115) with minimal G6PD activity. The prevalence of partial G6PD deficiency in female neonate group was 3.42% (21/614) by enzyme assay versus 0.49% (3/614) by FST. This study concluded that our routine screening method using FST was unable to diagnose female heterozygotes. We recommend using this quantitative enzyme assay method by OSMMR-D kit since it was more sensitive in detecting G6PD deficiency in female neonates compared to FST.