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Y K Kueh

Publications and source records attributed to Y K Kueh.

At least 37 records · Page 2Linked to original sources
PubMed1991

Prognostic usefulness of cytogenetic analysis for haematological malignancies--two case reports on acute myeloid leukaemia.

Since the setup of marrow cytogenetic analysis at the National University Hospital (NUH) of Singapore in 1988, we have systematically examined all patients with haematological neoplasia for clonal abnormalities. In most patients, diagnosis was unequivocal on clinical and morphological grounds so that karyotyping was undertaken for prognostic purposes. Two patients are described who illustrate the prognostic implications of nonrandom chromosomal derangements. They highlight the increasing appreciation of the importance of cytogenetic analysis as an independent and reliable prognostic tool in the management of haematological malignancies.

Acute Disease↗
PubMed1991

Reversible pure red cell aplasia associated with diphenylhydantoin therapy.

Pure red cell aplasia (PRCA) is characterised by an anaemia with reticulocytopenia but with normal leukocyte and platelet counts, and a bone marrow with the selective absence of erythroid precursor cells. Drug-induced PRCA is a rare cause of secondary erythroid aplasia, but distinct from the primary and most secondary forms, it is usually acute and fully reversible upon withdrawal of the causative drug. We report a 36 year-old Chinese man who developed diphenylhydantoin associated PRCA two months after commencing the treatment. Reappearance of reticulocytes was observed six days following the cessation of diphenylhydantoin therapy and the haemoglobin level rose to normal one month later. The extreme rarity of this adverse reaction to a drug used so widely strongly suggests an individual predisposition.

Adult↗
PubMed1991

Haematological adverse drug reactions in hospital practice.

A variety of drug-related haematological reactions is regularly encountered in a general hospital. These adverse drug reactions usually manifest as abnormal peripheral blood cell counts, which are usually low, involving one or more cell lines, but which may sometimes be raised as in drug-induced eosinophilia. Antineoplastic cytotoxic therapy, predictably, gives rise to cytopenias, which constitute the bulk of adverse haematological changes encountered in hospital practice. This paper addresses itself primarily to the unpredictable class of drug reactions which keeps the clinician vigilant. Its emphasis is on the clinical aspects and pathogenetic mechanisms of these iatrogenic haematological complications. Differences in tissue pattern of reaction to the same drug and the wide range of unrelated drugs capable of inducing a similar haematological aberration emphasises the role of individual susceptibility as the single most important factor in adverse drug reactions. Clarification of the pathogenetic mechanisms of different adverse drug reactions will ultimately come from the fields of pharmacogenetic and molecular genetics.

Agranulocytosis↗
PubMed1990

Cytogenetic analysis in myeloid malignancies.

Forty-one patients with myeloid malignancies, majority newly diagnosed and previously untreated, were systematically karyotyped between January 1988 and December 1989 using fluorodeoxyuridine (FdU) synchronisation and Giemsa banding techniques. Eighteen patients had acute myeloid leukaemia (AML), 13 had one form or other of a myeloproliferative disorder and 10 fulfilled the clinical and morphological criteria for the myelodysplastic syndrome (MDS). Ten AML patients had cytogenetic abnormalities. All 6 chronic myeloid leukaemia (CML) patients carried the Philadelphia chromosome with 2 having additional abnormal clones. Only four MDS patients showed involvement of either chromosome 5 or 7.

Adolescent↗
PubMed1990

Chemotherapy of adult acute myeloid leukaemia.

Great strides have been made in the chemotherapy of adult acute myeloid leukaemia in the last two decades. This paper describes our experience in the treatment of adult acute myeloid leukaemia from 1980-88. About two thirds of patients achieve remission with a standard chemotherapy protocol. Early disease relapse and measures to prevent it are major problems. The majority of patients with adult myeloid leukaemia, presently, are not cured with chemotherapy alone.

Adolescent↗
PubMed1989

Agranulocytosis and anaemia induced by sulfametopyrazine in a sulfametopyrazine-trimethoprim combination.

We report a case of prolonged fever, agranulocytosis, and anaemia associated with the long acting sulphametopyrazine-trimethoprim combination (Kelfiprim). A woman of 23 years took an overdose of 13 tablets over five days for presumed cystitis. One day after the last dose the patient developed fever and a generalised rash. The fever persisted and her previously normal leukocyte count decreased to 1.8 x 10(9)/1. After treatment with paracetamol the fever settled briefly, and then recurred for another 16 days. A later peripheral blood leukocyte count of 0.77 x 10(9)/1, haemoglobin of 10.8 g/dl, and a hypocellular bone marrow with depressed granulopoiesis and haemopoiesis suggested marrow suppression induced by sulfametopyrazine. Since the IgM antibody against the Epstein-Barr virus capsid antigen was detected, the adverse drug reaction might have been aggravated by this virus. The case highlights the risk of severe haematological adverse reactions associated with sulphonamide treatment, and argues for the use of trimethoprim alone for uncomplicated cystitis.

Adult↗
PubMed1989

Incidence of thrombocytopenia in an acute care hospital.

Our recent survey recorded thrombocytopenia in 1 per 105.5 adults inpatients in an acute care hospital. Less than 30% of these patients demonstrated any bleeding manifestations. The high pickup rate of asymptomatic thrombocytopenia is a spin off from the current practice of recording the platelet count with every full blood count request. 46.6% of our thrombocytopenic patients had an underlying infection. The high association between thrombocytopenia and infection justifies a search for an infective process when one encounters an unexpected or unexplained reduction in the platelet count.

Adult↗
PubMed1989

Hereditary protein C deficiency--the first symptomatic family in Singapore.

Protein C is an important physiological inhibitor of coagulation. A deficiency of this protein is a recognised cause of recurrent venous thromboembolism. The assay for protein C was not locally available until recently. Our investigation of a young Malay woman who had sustained two previous pulmonary emboli led us to identify the first family in Singapore with this familial disorder. The definitive diagnosis of symptomatic protein C deficiency justifies longterm anticoagulant therapy in two members of this family. We now systematically screen all young adults who present with the first episode of deep venous thrombosis or pulmonary embolism irrespective of whether the event is spontaneous or seemingly precipitated.

Adult↗
PubMed1988

Acquired factor VIIIC deficiency due to circulating factor VIIIC inhibitors.

The management of patients with Factor VIIIC inhibitor is frequently a therapeutic challenge. Treatment is often individualized. We describe 3 patients, nonhaemophilic adults, with bleeding diatheses caused by a circulating inhibitor to Factor VIIIC. One patient had long standing rheumatoid arthritis. The other two did not have any apparent underlying disease, although one of them had an antecedent antecedent phenylbutazone injection for arthralgias. Prednisolone was prescribed for two patients which resulted in rapid clinical improvement and the eventual normalization of Factor VIIIC activity. The role and rationale of immunosuppressive therapy in Factor VIIIC inhibitor is reviewed.

Adult↗
PubMed1988

Murine typhus infection complicated by dengue haemorrhagic fever.

Murine typhus is endemic in many South East Asian countries but it has not been reported from the island of Borneo. Recently we attended to an English lady who contracted the disease in Brunei. Her clinical course unexpectedly turned stormy in the third week of the illness accompanied by severe thrombocytopenia. She made a complete recovery. Serological studies here and subsequently in England confirmed that she suffered from recent murine typhus infection complicated by dengue haemorrhagic fever.

Adult↗
PubMed1987

Prevalence of hepatitis B markers in psychiatric in-patients in Singapore: a pilot study.

The prevalence of hepatitis B infection among 71 patients in an adult psychiatric hospital was determined by testing for hepatitis B surface antigen (HBsAg), its antibody (anti-HBs) and antibody against hepatitis B core antigen (anti-HBc). The results showed 12.7 per cent positive for HBsAg, 63.4 per cent positive for anti-HBs and 69 per cent positive for anti-HBc. This assessment of the prevalence of hepatitis B in a group of adult long-term institutional patients may be used as a guide when hepatitis B vaccination is being considered for use in a psychiatric hospital. The need for a similar study on health care personnel working in the same institution is emphasized.

Adolescent↗
PubMed1986

Congenital enzymopenic methaemoglobinaemia.

Methaemoglobin is haemoglobin in which the sixth coordination position of heme iron is in the ferric state, having lost an unpaired electron. In normal human blood the level of methaemoglobin is 1% or less. This stable level results from an equilibrium between the rate at which ferric heme is formed and the rate at which it is reduced back to the ferrous state. Congenital methaemoglobinaemia caused by a deficiency or absence of methaemoglobin reductase represents a disturbance of this equilibrium wherein the methaemoglobin formed at physiological rate is not efficiently reduced. A chronically elevated level of oxidized haemoglobin results. Methaemoglobin is incapable of binding oxygen. Instead of the bright red colour imparted by oxyhaemoglobin, blood containing more than 10% methaemoglobin is dark brown. A concentration exceeding 1.5 g/d1 gives rise to cyanosis. The majority of patients with congenital enzymopenic methaemoglobinaemia are asymptomatic despite the intense cyanosis. This is a very important differentiating point from the cyanosis of cardiopulmonary causes. Methaemoglobin reductase deficiency is uncommon. Most proven cases had been in persons of European descent with sporadic reports of non-Caucasoid patients. We report here a Chinese patient whom we believe is the first in South East Asia to have methaemoglobin reductase deficiency unequivocally documented.

Adult↗
PubMed1986

Eosinophilic purpura--the syndrome of acquired platelet dysfunction with eosinophilia--a tropical phenomenon.

Eosinophilic purpura, the syndrome of acquired platelet dysfunction with eosinophilia was first recognized in Singaporean children and later described in Thai children. It is a benign, transient thrombopathy associated with significant eosinophilia and characterized by the sudden onset of a superficial bleeding tendency. The first young adult with this haemostatic disturbance was documented in a National Servicemen 4 years ago. We report here our experience with 16 such patients (13 males, 3 females) and concur with the original observers on the benign nature of this syndrome. Stool helminths were present in 50% of the cases but the duration of symptoms and platelet dysfunction appeared unaffected by the rapidity with which the eosinophil count returned to normal following antihelminthic treatment. If platelet aggregation study is readily available it is desirable to document the presence of an abnormal platelet response to one or more aggregating agents but without it, it is still possible to diagnose this syndrome fairly confidently in the healthy, young patient in the first or second decade of life who develops recent onset bruising with or without mucosal bleeding, whose preliminary blood cell counts are normal apart from a moderate to marked absolute eosinophilia.

Adolescent↗
PubMed1985

Hereditary haemorrhagic telangiectasia: the use of H2 receptor antagonist in symptomatic gastric telangiectasia.

Hereditary haemorrhagic telangiectasia is an autosomal dominant disorder characterized by the presence of mucocutaneous dilatation of capillaries and venules. The underlying defect, a deficiency of vascular elastic tissue and muscle, predisposes these vessels to injury and inadequate contractility. Recurrent epistaxis or gastrointestinal haemorrhage is the clinical hallmark of the symptomatic patient. Management is frequently individualized as no modality of therapy has been found to be universally effective. The purpose of this communication is to discuss the use of H2 receptor antagonist in symptomatic gastric telangiectasia.

Aged↗
PubMed1985

Home blood glucose monitoring, glycaemic control and diabetic complications.

The aim of this study was to evaluate the effect of home blood glucose monitoring on diabetic complications and metabolic control. Forty Chinese and Indian patients participated in the Diabetic Society of Singapore National Home Blood Glucose Monitoring (HBGM) Programme. The clinical progress, the blood glucose and glycosylated haemoglobin concentrations, and the platelet aggregation of the aforementioned patients were studied over a 6-month period; the results were compared with those from a matched, albeit smaller, control group of 18 diabetic patients who were on treatment but not in the HBGM programme. At the end of the six month period, three patients in the control group showed clinical deterioration of peripheral neuropathy in contrast to one patient on HBGM. Due to the small number of patients, the difference in the findings was not statistically significant. Patients on HBGM demonstrated significant improvement in mean grouped blood glucose profile values, 135 +/- 8 to 118 +/- 5 mg/dl, p less than 0.01, and glycosylated haemoglobin levels, 10.3 +/- 0.4 to 9.3 +/- 0.3%, p less than 0.01. The platelet aggregability was unchanged. In contrast, patients in the control group developed a significant increase in platelet aggregation (30 +/- 4% to 37 +/- 5%, p less than 0.05), although the blood glucose and glycosylated haemoglobin concentrations were not significantly altered. This study demonstrated that patients on a six-month HBGM programme were able to achieve improved glycaemic control associated with a trend towards decreased deterioration of diabetic neuropathy and platelet aggregability.

Adult↗
PubMed1984

Myelodysplastic syndromes: an analysis of clinical and haematological features.

A retrospective analysis of 24 cases of myelodysplastic syndromes was performed between 1979-1984. There were 16 men and 8 women with a mean age of 69 years and 65 years respectively. The most common haematological features at initial presentation were refractory macrocytic anaemia, reticulocytopenia and associated with either bicytopenia or pancytopenia. The bone marrow was often cellular with megaloblastoid erythropoiesis and in 7 patients (29%), there were ring sideroblasts. Often there was associated dysgranulopoiesis and dysthrombopoiesis Myelodysplastic syndromes appear morphologically to be a heterogenous entity. An attempt to classify them according to the recent proposal of the French-American-British (FAB) Co-operative Group was made. Transformation into acute non-lymphocytic leukaemia occurred in 6 patients (25%). The mean interval between diagnosis and transformation to acute leukaemia was 13 months (range 3-30 months). Acute leukaemia in these patients were refractory to conventional chemotherapy. There were 14 deaths (58%) observed during the period and the common causes of deaths were acute leukaemia, infections and haemorrhage. At present there is no specific or generally effective therapy for this haematologic entity.

Aged↗
PubMed1984

Plasma exchange in the management of acute polyradiculopathy and myasthenic crisis (plasma exchange in neurological disorders).

Six patients with acute severe neurological illnesses were managed by plasma exchange on the basis that their diseases were triggered by immune mechanisms. These included one case of acute post-infectious encephalomyeloradiculopathy, two cases of Guillain Barré Syndrome or acute polyradiculoneuropathy and three patients in myasthenic crisis. There were no convincing responses in the patients with Guillain Barré Syndrome. All three myasthenic patients showed improvement that was sufficiently dramatic to warrant continued use of this therapeutic procedure. Based on our experience and reports by others it is felt that in acute polyradiculoneuropathy plasmapheresis would be beneficial only if the disease is predictably deteriorating and should be done within the first few days. In myasthenic crises its role is more definite and it shortens significantly the duration of assisted ventilation and the length of severe relapse. The procedure also gives the physician sufficient time to effectively immunosuppress the patients.

Acute Disease↗