MyMedR

Fulltext Experience with primary myelodysplastic syndromes in a university haematology unit: report of five cases

Cheong SK, Ainoon O

Med J Malaysia, 1987 Dec;42(4):272-5.

Myelodysplastic syndromes appear to be a rare group of blood disorders in Malaysia. It usually affects the elderly and some of the cases were reported to evolve into acute leukemia. We describe our experience with five cases, seen and managed by us over a 5-year period. All patients receiving supportive therapy died with one of them definitely known to transform to acute leukemia. The patient who survives till the time of writing received low dose continuous cytosine arabinoside infusion.

Fulltext Hairy cell leukemia. A case report

Ainoon O, Megat R, Cheong SK, Halimah Y

Med J Malaysia, 1988 Mar;43(1):62-4.

PMID: 3244323

Evaluation of the Contraves Autolyzer 801

Lim YC, Cheong SK, Joyce JA, Ainoon O, Jeyasekeran V, Menaka N

Malays J Pathol, 1990 Jun;12(1):43-9.

PMID: 2090889

The Contraves Autolyzer 801 is a 20 parameter cell counter that operates on the principle of impedance. This evaluation study found that the within-batch precision for 5 of its parameters--WBC, RBC, Hb, Hct and Plt--had coefficients of variation below 5%, while the counts for red cell parameters were reproducible for up to 3 days. The analyser exhibited good linearity for all the parameters. When compared with 2 other counters--the Coulter S-Plus and the Coulter M350, some degree of proportional and constant bias due to unsuitable calibration were detected in the WBC, Hct and Plt parameters. Otherwise it showed generally good correlation in all the parameters and also with the manual PCV method. Carry over was negligible in the red cell parameters. The Contraves Autolyzer 801 is easy to operate and readily accepted by operators.

Single incubation double esterase cytochemical reaction using a single coupling reagent

Ainoon O, Jabamoney AJ, Cheong SK

Malays J Pathol, 1991 Jun;13(1):47-9.

PMID: 1724544

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.

Immunophenotyping of peroxidase-negative acute leukaemias using immunoalkaline phosphatase (APAAP) method

Cheong SK, Lim YC, Ainoon O, Hamidah NH

Malays J Pathol, 1991 Dec;13(2):119-21.

PMID: 1823093

Immunophenotyping of acute leukaemias has become an important diagnostic tool in haematology laboratories as it is now well recognised that the presence of certain surface markers has prognostic significance. In 1988, we experimented with the alkaline phosphatase anti-alkaline phosphatase (APAAP) method for immunophenotyping of leukaemic cells in our laboratory. 48 cases of peroxidase-negative acute leukaemias were studied. Our study showed that 2 peroxidase-negative cases carried myeloid surface markers, 44% were negative for the markers studied and 5% were unclassified due to technical problems. We concluded that the APAAP method is a useful technique for demonstrating cell markers in leukaemic cells as the reaction is reddish and usually intense. We failed to demonstrate surface markers in 44% of the cases probably because of the choice of a limited panel of monoclonal antibodies.

Fulltext First trimester prenatal diagnosis of beta-thalassaemia following chorionic villus sampling

Chandran R, Ainoon O, Anson I, Anne J, Cheong SK

Med J Malaysia, 1993 Sep;48(3):341-4.

PMID: 8183149

DNA analysis for the diagnosis of beta-thalassaemia is a relatively new technique in Malaysia. This, combined with chorionic villus sampling, has enabled us to offer prenatal diagnosis in the first trimester for this common condition. To the best of our knowledge, this has not hitherto been reported in Malaysia.

In vivo evidence of all-trans retinoic acid inducing maturation in acute promyelocytic leukaemia

Hamidah HN, Cheong SK, Ainoon O

Acta Haematol., 1993;89(1):50-1.

PMID: 8480488

All-trans retinoic acid therapy induces maturation in acute promyelocytic leukaemia. We document in vivo evidence of differentiation by all-trans retinoic acid in a case of acute promyelocytic leukaemia which was characterized by cytoplasmic vacuolations.

Fulltext Pregnancy in a patient receiving busulphan for chronic myeloid leukaemia

Norhaya MR, Cheong SK, Hamidah NH, Ainoon O

Singapore Med J, 1994 Feb;35(1):102-3.

PMID: 8009265

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.

Fulltext Thalassaemia in Malaysia: a strategy for prevention

Ainoon O, Cheong SK

Malays J Pathol, 1994 Jun;16(1):23-7.

PMID: 16329572

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.

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

Boo NY, Ainoon O, Arif ZA, Cheong SK, Haliza MS

J Paediatr Child Health, 1995 Feb;31(1):44-6.

PMID: 7748690

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.

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

Ainoon O, Joyce J, Boo NY, Cheong SK, Hamidah NH

Malays J Pathol, 1995 Dec;17(2):61-5.

PMID: 8935127

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.

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

Norhaya MR, Cheong SK, Hamidah NH, Ainoon O

Singapore Med J, 1996 Jun;37(3):320-2.

PMID: 8942241

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.

Unexpected Epithelial Membrane Antigen (EMA) and Cytokeratin Expression in a Case of Infantile Acute Monoblastic Leukaemia

Cheong SK, Chin SF, Azizon O, Ainoon O, Hamidah NH

Hematology, 1996;1(3):223-5.

PMID: 27406616 DOI: 10.1080/10245332.1996.11746308

A previously healthy eleven month old male Malay infant presented with fever, upper respiratory tract infection and right knee swelling. Pallor, bilateral proptosis, hepatosplenomegaly, multiple scalp swellings and a right cheek swelling were observed. Investigations revealed that he had acute monoblastic leukemia or FAB M5a. Immunophenotyping by flow cytometry showed that the blast cells were positive for CD45, CD13, CD33, HLA-DR, CDllc, CD71, EMA, and Cytokeratin. They were negative for CD34, CD19, CD10, CD22, CD2, CD3, CD4, CD7, CD8, CD61, NK, Glycophorin A, and CD14. The monoblasts were used to evaluate anti-EMA and anti-cytokeratin. They were unexpectedly found to be positive. Acute monoblastic leukaemias are well known to show extramedullary infiltration and this may be their primary mode of presentation. Thus, in immunochemostry, when using EMA and cytokeratin expression in the differential diagnosis of neoplastic diseases, it is important to consider that monoblasts may express these markers as illustrated by this case.

Fulltext Painful oral ulcers with hydroxyurea therapy

Norhaya MR, Cheong SK, Ainoon O, Hamidah NH

Singapore Med J, 1997 Jul;38(7):283-4.

PMID: 9339092

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.

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

Tay SP, Cheong SK, Hamidah NH, Ainoon O

Malays J Pathol, 1998 Dec;20(2):91-4.

PMID: 10879268

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.

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

Leong CF, Cheong SK, Hamidah NH, Ainoon O, Kannaheswary Y

Malays J Pathol, 1998 Dec;20(2):103-8.

PMID: 10879271

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.

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

Tay SP, Cheong SK, Hamidah NH, Ainoon O

Malays J Pathol, 1999 Jun;21(1):37-43.

PMID: 10879277

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.

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

Ainoon O, Joyce J, Boo NY, Cheong SK, Zainal ZA, Hamidah NH

Hum Mutat, 1999 Oct;14(4):352.

PMID: 10502785 DOI: 10.1002/(SICI)1098-1004(199910)14:4<352::AID-HUMU1

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.

Detection of immunoglobulin gene rearrangement in B-cell malignancies

Ainoon O, Hamidah AB, Cheong SK, Hamidah HN

Malays J Pathol, 2000 Jun;22(1):5-11.

PMID: 16329531

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.

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

Ainoon O, Yu YH, Amir Muhriz AL, Boo NY, Cheong SK, Hamidah NH

Hum Mutat, 2003 Jan;21(1):101.

PMID: 12497642 DOI: 10.1002/humu.9103

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.

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