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O Ainoon

Publications and source records attributed to O Ainoon.

At least 19 recordsLinked to original sources
PubMed2006

G6PD deficiency with hemolytic anemia due to a rare gene deletion--a report of the first case in Malaysia.

A 2-year-old Chinese boy was referred to Hospital UKM for investigation of recurrent episodes of dark-coloured urine and pallor since birth. He was born prematurely at 34 weeks gestation and developed severe early-onset neonatal jaundice requiring exchange blood transfusion. Screening at birth showed Glucose-6-phosphate dehydrogenase (G6PD) deficiency. On admission, physical examination revealed pallor, jaundice and mild hepatomegaly. Results of laboratory investigations showed a hemoglobin level of 11.0 g/dl with a hemolytic blood picture, reticulocytosis of 20% and red cell G6PD activity reported as undetectable. The patient's DNA was analysed for G6PD mutations by PCR-based techniques and DNA sequencing and results showed a 24 bp deletion of nucleotide 953-976 in the exon 9 of the G6PD gene. DNA analysis was also performed on blood samples of the patient's mother and female sibling confirming their heterozygous status, although both showed normal red cell G6PD activity levels. The patient was discharged well and his parents were appropriately advised on the condition and the importance of taking folic acid regularly. This is a first case report in Malaysia of G6PD deficiency causing chronic-hemolytic anemia. The rare 24 bp deletion causes the G6PD Nara variant, previously reported only in two other unrelated males, a Japanese and a Portuguese both with chronic hemolytic anemia.

Anemia, Hemolytic↗
PubMed2003

Glucose-6-phosphate dehydrogenase (G6PD) variants in Malaysian Malays.

We performed DNA analysis using cord blood samples on 86 male Malay neonates diagnosed as G6PD deficiency in the National University of Malaysia Hospital by a combination of rapid PCR-based techniques, single-stranded conformation polymorphism analysis (SSCP) and DNA sequencing. We found 37.2% were 871G>A (G6PD Viangchan), 26.7% were nt 563 C>T (G6PD Mediterranean) and 15.1% were 487G>A (G6PD Mahidol) followed by 4.7% 1376G>T (G6PD Canton), 3.5% 383T>C (G6PD Vanua Lava), 3.5% 592C>T (G6PD Coimbra), 2.3% 1388G>A (G6PD Kaiping), 2.3% 1360C>T (G6PD Union), 2.3% 1003G>A (G6PD Chatham), 1.2% 131C>G (G6PD Orissa) and 1.2% 1361G>A (G6PD Andalus). Seventy-one (82.6%) of the 86 G6PD-deficient neonates had neonatal jaundice. Fifty seven (80%) of the 71 neonates with jaundice required phototherapy with only one neonate progressing to severe hyperbilirubinemia (serum bilirubin >340 micromol/l) requiring exchange transfusion. There was no significant difference in the incidence of neonatal jaundice, mean serum bilirubin level, mean age for peak serum bilirubin, percentage of babies requiring phototherapy and mean number of days of phototherapy between the three common variants. In conclusion, the molecular defects of Malay G6PD deficiency is heterogeneous and G6PD Viangchan, Mahidol and Mediterranean account for at least 80% of the cases. Our findings support the observation that G6PD Viangchan and Mahidol are common Southeast Asian variants. Their presence in the Malays suggests a common ancestral origin with the Cambodians, Laotians and Thais. Our findings together with other preliminary data on the presence of the Mediterranean variant in this region provide evidence of strong Arab influence in the Malay Archipelago.

DNA Mutational Analysis↗
PubMed2003

Semiquantitative screening test for G6PD deficiency detects severe deficiency but misses a substantial proportion of partially-deficient females.

Neonatal screening for G6PD deficiency has long been established in many countries. The aim of the study was to determine whether the routine semiquantitative fluorescent spot test could detect all cases of G6PD deficiency, including those cases with partial deficiency (residual red cell G6PD activity between 20-60% of normal). We compared the results of G6PD screening by the semiquantitative fluorescent spot test and quantitative G6PD activity assay on a group of 976 neonates and 67 known female heterozygotes. The values for mean G6PD activity of G6PD-normal neonates and 293 healthy adult females were determined. There was no significant difference in the mean normal G6PD activity between the two racial groups in the neonates (669 Malays, 307 Chinese) and in the 293 healthy adult females (150 Malays, 143 Chinese) group. The values for the upper limits of total deficiency (20% of normal residual activity) for neonates and adult females were 2.92 U/gHb and 1.54 U/gHb, respectively. The upper limits of partial deficiency (60% of normal residual activity) were 8.7 U/gHb and 4.6 U/gHb respectively. The prevalence of G6PD deficiency among the male neonates was 5.1% (26) by both the fluorescent spot test and the enzyme assay method. The G6PD activity levels of all 26 cases of G6PD-deficient male neonates were < 20% normal (severe enzyme deficiency). In the female neonate group, the frequency of G6PD deficiency was 1.3% (6 of 472) by the fluorescent spot test and 9.35% (44 of 472) by enzyme assay. The 6 cases diagnosed as deficient by the fluorescent spot test showed severe enzyme deficiency (< 2.92 U/gHb). The remaining 38 female neonates had partial enzyme deficiency and all were misdiagnosed as normal by the fluorescent spot test. In the female heterozygote group, G6PD deficiency was diagnosed in 53% (35 of 67) by enzyme assay and in 7.5% (4 of 67) of cases by the fluorescent spot test. The 4 cases detected by fluorescent spot test had severe enzyme deficiency (<1.6 U/gHb). The remaining 31 (46.3%) cases, diagnosed as normal by fluorescent spot test, showed partial G6PD deficiency. In conclusion, we found that the semiquantitative fluorescent spot test could only diagnose cases of total G6PD deficiency and misclassified the partially-deficient cases as normal. In this study, the overall prevalence of G6PD deficiency was 3.28% by the semiquantitative fluorescent spot test and 7.17% by enzyme assay. This means that 3.9% of G6PD-deficient neonates were missed by the routine fluorescent spot test and they were found to be exclusively females. This study demonstrates a need to use a method that can correctly classify female heterozygotes with partial G6PD deficiency. The clinical implication is that these individuals may be at risk of the hemolytic complication of G6PD deficiency.

Adult↗
PubMed2003

Allogeneic haemopoietic stem cell transplantation using non-myeloablative conditioning--a local experience.

Allogeneic haemopoietic stem cell transplantation was initially considered as a means of delivering supralethal doses of chemotherapy with or without total body irradiation for the treatment of malignancy. However, it has become clear that this mode of therapy does not eradicate the malignancy in many patients and its benefit is largely due to the immune mediated graft versus malignancy effect. This has led to development of alternative strategy to utilize a less intensive preparative regimen pre-transplantation that provides sufficient immunosuppression to achieve engraftment of an allogeneic stem cell graft, thus allowing the evolution of a graft versus malignancy effect post-transplantation. Since September 1999, we had carried out 10 cases of allogeneic peripheral blood stem cell transplantation: one case of aplastic anaemia, four cases of acute myeloid leukemia (AML) in first remission, and five cases of chronic myeloid leukemia (CML) in chronic phase. The preparative regimen was non-myeloablative comprising Fludarabine with Cyclophosphamide or Busulphan. Recovery from transplantation was rapid with no or brief period of neutropenia or thrombocytopenia. Engraftment was established by determining donor's short tandem repeats in the recipient's bone marrow at day 30, 60 and 100 post-transplantation. Seven cases (70%) show partial or complete donor's chimerism by day 30 indicating successful engraftment. No treatment mortality was noted at day 100. Graft versus host disease was generally limited. Up to the date of reporting, two patients with CML had graft failure, one was successfully re-transplanted later. Two patients with AML had since relapsed and passed away. The others remain alive and well. The cost of transplantation on average was estimated to be about a quarter of that using a myeloablative regimen. It appears that this treatment strategy is a promising approach for the management of blood disorders.

Adolescent↗
PubMed2000

Detection of immunoglobulin gene rearrangement in B-cell malignancies.

Rearrangement of the immunoglobulin heavy chain (IgH) gene has been used as a marker of lineage and clonality in the diagnosis of B lymphoproliferative disorders. A number of PCR-based techniques have been developed to overcome the disadvantages of Southern blotting, the standard technique in detecting IgH gene rearrangement. Using an established seminested PCR technique with consensus primers to the V and J regions of the IgH gene, we analysed DNA prepared from peripheral blood and/or bone marrow specimens from 30 cases of known B cell malignancies (16 chronic lymphocytic leukemia, 11 acute lymphoblastic leukemia and 3 Non-Hodgkin Lymphoma), 3 cases of T lymphoproliferative disease and 3 cases of reactive lymphocytosis diagnosed in Hospital UKM to detect rearranged IgH gene. We found that monoclonality as represented by the presence of rearranged IgH gene were demonstrated in all the 30 cases. The PCR findings showed 100% concordance with the Southern blot analysis results which also showed rearranged IgH bands in all the 30 cases. We also found that none of the cases of T lymphoproliferative diseases and reactive lymphocytosis showed presence of rearranged IgH band, suggesting that the amplification using the IgH primers is lineage-specific. In conclusion, we find the PCR a useful method to detect IgH gene rearrangement in peripheral blood and bone marrow specimen. Since the PCR results are comparable to that of the Southern blotting in demonstrating B cell monoclonality and owing to its many advantages we feel that it can replace the Southern blot technique for the diagnosis of B cell malignancies.

B-Lymphocytes↗
PubMed1999

Glucose-6-phosphate dehydrogenase (G6PD) variants in Malaysian Chinese.

We screened 38 G6PD-deficient male Chinese neonates for known G6PD mutations using established PCR-based techniques. We found 50.0% (19 of 38) were mutation 1376G>T, 34.2% (13 of 38) were mutation 1388G>A, 5.2% (2 of 38 ) were mutation 95A>G and 2.2% (1 of 38) was mutation 1024C>T. In 7% (3 of 38) of the cases the mutations remained uncharacterised. Sixty three percent (24 of 38) of the G6PD deficient neonates had neonatal jaundice with 28.9 % (11 of 38) developing moderate to severe hyperbilirubinemia. The group of neonates with 1388 mutation showed the highest incidence of moderate to severe hyperbilirubinemia requiring phototherapy and/or exchange transfusion respectively. Majority (70%) of the G6PD deficient neonates showed severe enzyme deficiency. However, there was no meaningful association between the level of enzyme activity and the severity of neonatal jaundice. In summary, four mutations account for more than 90% of the G6PD deficiency cases among the Chinese in Malaysia and the pattern of distribution of the molecular variants is similar to those found among the Chinese in Taiwan and southern mainland China. Our findings also suggest the possible association of nt 1388 mutation with severe neonatal jaundice.

Amino Acid Substitution↗
PubMed1999

Comparative analysis of three permeabilization methods for cytofluorometric evaluation of cytoplasmic myeloperoxidase.

A comparative study was conducted to evaluate three different permeabilization methods: FACS Permeabilizing Solution (FPerm), CytoFix/CytoPerm Kit (CFP) and Paraformaldehyde-Tween 20 (PFT) reagents, in cytoplasmic labeling of myeloperoxidase (MPO). Peripheral blood cells from 23 healthy subjects were fixed and permeabilized according to the proposed procedures, prior to direct immunofluorescence staining with CD14, CD45, IgG1, IgG2 and MPO monoclonal antibodies (McAb). Subsequent flow cytometric analysis was performed on FACSCalibur flow cytometer (Becton Dickinson, BD). As far as the antigenic expression of MPO in normal samples is concerned, FPerm and CFP demonstrated better cytoplasmic staining by inducing minor effects on light-scattering properties of the cell populations, whereas PFT-treated samples showed a diminished ability to distinguish the cell types. However, the simple and rapid FPerm method required an earlier processing of samples since the stored whole blood samples (for more than 8 hours) tended to show a significant decrease of fluorescence intensity. We also have demonstrated that P/N ratio possesses added value in evaluation of cell reactivity in immunophenotyping, based upon the apparent nonspecific cytoplasmic staining of MPO in the lymphocyte population.

Adult↗
PubMed1998

Flow cytometric analysis of intracellular myeloperoxidase distinguishes lymphocytes, monocytes and granulocytes.

A study was undertaken to evaluate the ability of flow cytometric analysis of intracellular myeloperoxidase (MPO) in differentiating populations of lymphocytes (L), monocytes (M) and granulocytes (G), by means of lysed whole blood method. Anticoagulated blood from 23 normal individuals was lysed with FACS lysing solution and permeabilized with FACS permeabilizing solution before subjected to direct immunofluorescence staining. The geometric means of the fluorescence intensity were measured using FACSCalibur flow cytometer (Becton Dickinson). Populations of L, M and G were gated based on their light scatter characteristics and expression of CD14 and CD45. Then, the fluorescence intensity of MPO expression was studied in these individual cell populations. The results showed that fluorescence intensity of MPO was the strongest in G and weakest in L, whereas M showed intermediate fluorescence intensity. Our findings reveal that discrimination of these three cell types is achievable based upon the sole expression of intracellular MPO.

Antigens, Surface↗
PubMed1998

Serum ferritin and lactate dehydrogenase in a case of hemophagocytic lymphohistiocytosis.

A 40-day-old baby girl presented with intermittent fever, lymphadenopathy, massive hepatosplenomegaly, progressive pancytopenia and features of disseminated intravascular coagulopathy. A bone marrow aspiration was performed and showed florid histiocytic proliferation with marked hemophagocytosis. Based on the diagnostic guideline for Hemophagocytic Lymphohistiocytosis proposed by the Familial Hemophagocytic Lymphohistiocytosis Study Group of Histiocyte Society, this patient has fulfilled most of the criteria. We have also found that serum ferritin and lactate dehydrogenase to be very high in this patient. It remains uncertain whether the disorder is reactive or neoplastic.

Bone Marrow Cells↗
PubMed1997

Painful oral ulcers with hydroxyurea therapy.

Five patients treated with hydroxyurea for various haematological malignancies developed multiple painful oral ulcers. Their neutrophil counts were either normal or elevated. The ulcers disappeared with cessation of hydroxyurea. Oral ulcers recurred when hydroxyurea was resumed in one of the patients. As the patients were unable to tolerate this painful side effect, hydroxyurea had to be discontinued. Appearance of painful oral ulceration seems to be independent of dosing rate or total cumulative dose of hydroxyurea.

Adolescent↗
PubMed1996

Sweet-like syndrome in a patient with acute myeloid leukaemia.

A 45-year-old Malay lady developed brisk vesicular, plaque-like reaction to a Mantoux test concomitant with a diagnosis of acute myeloid leukaemia (AML). The lesion resolved one month after chemotherapy. Similar lesions developed later after she was bitten by mosquitoes on the forearms. She also had the lesions over her cheek. A skin biopsy showed infiltration of the dermis with neutrophils and some monocytoid cells. The lesion resolved one week after prednisolone therapy.

Diagnosis, Differential↗
PubMed1995

Enzyme activity of glucose-6-phosphate dehydrogenase-deficient Malaysian neonates during the first 10 days of life.

OBJECTIVE: The objective of this study was to determine the degree of severity of enzyme deficiency in glucose-6-phosphate dehydrogenase (G6PD)-deficient Malaysian neonates as part of an effort to identify risk factors associated with severe hyperbilirubinaemia in G6PD-deficient infants. METHODOLOGY: During this study, enzyme activity was measured in 53/59 (89.8%) hospital-diagnosed G6PD-deficient neonates (34 Malays, 12 Chinese, and seven other ethnic groups) born consecutively in the Kuala Lumpur Maternity Hospital. All neonates, except one, were males. RESULTS: The mean level of enzyme activity of the 52 males G6PD-deficient neonates (0.47 iu/g Hb, 95% confidence intervals: 0.37, 0.57) was less than 10% of that of normal Malaysian male neonates. The enzyme activity of the only female G6PD-deficient infant, at 1.11 iu/g Hb, was 12.5% of the mean G6PD enzyme activity of normal females. CONCLUSION: Our results showed that G6PD deficiency in Malaysian neonates predominantly affects males and is usually severe.

Analysis of Variance↗
PubMed1995

Nucleotide 1376 G-->T mutation in G6PD-deficient Chinese in Malaysia.

G6PD deficiency is the most common human enzymopathy and affects 200 million people worldwide. To date more than 400 biochemical variants and at least 60 different point mutations in the G6PD locus have been discovered. In Malaysia the overall incidence of G6PD deficiency among males is 3.1%, being more prevalent among the Chinese and Malays and less common among the Indians. As part of our initial effort to characterise G6PD deficiency in the Malaysian population, we investigated 18 G6PD deficient Chinese male neonates for the G6PD mutation G-->T at nt 1376, a common mutation seen among the Chinese in Taiwan and mainland China. The mutation was detected by a PCR-based technique using primers that artificially create a site for restriction enzyme Xho I. We found 61% (11 out of 18) of the Chinese G6PD deficient male neonates positive for this mutation. Study of enzyme electrophoretic mobility in 7 of the cases positive for this mutation revealed three different patterns of mobility. 107% (5 out of 7), 103% (1 out of 7) and 100% (1 out of 7). This study shows that mutation G-->T at nt 1376 is a common allele causing G6PD deficiency in Malaysians of Chinese origin. The finding of different patterns of electrophoretic mobility among the 7 cases positive for 1376 G-->T mutation supports the notion that diverse biochemical variants may share the same mutation.

Asian People↗
PubMed1994

Thalassaemia in Malaysia: a strategy for prevention.

In Malaysia, alpha-thalassaemia, beta-thalassaemia, haemoglobin (Hb) E, deltabeta-thalassaemia and Hb Constant Spring are prevalent. It has been estimated that 1 in 4 persons carries one of the above genetic abnormalities. In clinical practice, the major problems are: Hb Bart's hydrops fetalis (homozygous alpha(o)thalassaemia), homozygous 3(o)-thalassaemia, E-alpha thalassaemia and HbH disease. The laboratory procedures for diagnosis are standardised and the molecular basis of most of these genetic abnormalities are characterised. Thus it is possible to formulate a strategy for the detection and prevention of these disorders. The steps include the setting-up of population screening and genetic counselling service for the affected individuals, Society of Thalassaemias for public education and group support, and prenatal diagnosis with selective abortion of affected pregnancies. We embarked on such a programme between 1988 and 1992 in Kuala Lumpur General Hospital and hope to kindle similar effort in other state hospitals.

Adult↗
PubMed1994

Pregnancy in a patient receiving busulphan for chronic myeloid leukaemia.

A 33-year-old Malay lady with chronic myeloid leukaemia (CML) became amenorrhoeic during therapy with busulphan. Pregnancy was diagnosed via a urine pregnancy test and an ultrasound confirmed a viable foetus at 16 weeks. The busulphan was stopped. Her pregnancy was unremarkable and continued till term. She delivered a healthy child.

Adult↗
PubMed1991

Single incubation double esterase cytochemical reaction using a single coupling reagent.

Most methods used in double esterase cytochemistry for the diagnosis and classification of acute myeloid leukaemias require double incubation and staining, using separate coupling reagents. We evaluated a method by Swirsky on our normal and abnormal blood and bone marrow smears where only a single incubation and the use of a single coupling reagent is required. Its short incubation period and its strong positive reaction for butyrate esterase in demonstrating cells of monocytic lineage gives it an advantage over the conventional double incubation technique.

Esterases↗