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Publications (22)104.14 Total impact

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    ABSTRACT: To determine: (i) the prevalence of histological gastritis and peptic ulcer; and (ii) the clinical features of peptic ulcer, in patients with end-stage renal failure. Upper endoscopy was performed by a single observer in 268 patients with end-stage renal failure over a 6-year period. Gastric histology and Helicobacter pylori status were studied in 40 consecutive subjects in whom there were no contraindications for gastric biopsy and who had not used antibacterial drugs in the preceding 4 weeks. As there are only limited data for healthy volunteers in Singapore, 33 age-, sex- and race-matched patients with functional dyspepsia from an earlier drug trial and 18 healthy volunteers who were not age-matched were used as controls. The clinical features of 43 consecutive uraemic patients with peptic ulcer were compared with those of 118 consecutive non-uraemic peptic ulcer patients seen by the same author. Among uraemic patients, histological gastritis was less common, compared with healthy volunteers and functional dyspepsia patients. Helicobacter pylori infection as assessed by histology was also less common among uraemic patients compared with functional dyspepsia patients, but the difference was not statistically significant on serological assessment. Uraemic patients with ulcer had an equal sex ratio, in contrast to a male preponderance among peptic ulcer patients with normal renal function. Uraemic patients with ulcer were more likely to be pain-free, to present with haemorrhage, to have multiple ulcers and postbulbar duodenal ulcers, but were less likely to have H. pylori infection. Among uraemic subjects, the prevalence of H. pylori infection was similar whether or not peptic ulcer was present. The prevalence of histological gastritis was lower in uraemic patients when compared with patients with functional dyspepsia and healthy volunteers. Peptic ulcers in uraemic subjects have different clinical characteristics from peptic ulcer in non-uraemic subjects.
    Journal of Gastroenterology and Hepatology 09/1999; 14(8):771-8. · 3.33 Impact Factor
  • W C Lye, A Vathsala, W T Lee, S O Leong
    Transplantation Proceedings 12/1998; 30(7):3106-7. · 0.95 Impact Factor
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    ABSTRACT: Continuous ambulatory peritoneal dialysis (CAPD) is an important mode of therapy for patients with end-stage renal disease. Although techniques and patient survival rates have improved, the psychosocial rehabilitation of Asian CAPD patients has not been studied. The aim of this study is to measure the extent of psychosocial and psychiatric morbidity in a sample of Asian CAPD patients. Patients from the outpatient CAPD facility affiliated with a tertiary care hospital were randomly selected and enrolled in the study. Demographic and clinical data were collected. Psychosocial and psychiatric assessments using the Hospital Anxiety and Depression Scale and coping style questionnaires were performed by a trained psychiatrist. The patients' most bother-some symptoms and specific worries were noted. Thirty of 105 stable CAPD patients (mean age 54.2 +/- 14.1 years, M:F 1:2, mean duration on CAPD 22.3 +/- 8.3 months) were studied. Twenty-one patients were married. Twenty-two patients were uneducated, 19 were unemployed, and 9 were homemakers. Based on the Hospital Anxiety and Depression scales, 50% of the patients were identified as cases of anxiety and 13% as depression. Although 93% of the patients accepted their illness, 46% of the patients were in a state of despair and hopelessness. Pruritus was the most frequent complaint (40%), followed by dietary restrictions (23%). The main worries were financial in 83% of patients, sexual dysfunction in 73%, and unemployment in 67%. In conclusion, Asian CAPD patients have a high degree of undetected psychosocial and psychiatric morbidity. These issues need to be addressed to provide adequate psychosocial rehabilitation.
    Advances in peritoneal dialysis. Conference on Peritoneal Dialysis 02/1997; 13:134-6.
  • W C Lye, S O Leong, E J Lee
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    ABSTRACT: Renal artery stenosis of the transplant kidney occurs in approximately 6% of renal allograft recipients. Severe bilateral renal artery stenosis and unilateral renal artery stenosis to a single functioning kidney have been described as causes of recurrent pulmonary edema in nontransplant patients with normal cardiac function. We report 2 patients with severe transplant renal artery stenosis who presented with recurrent episodes of acute pulmonary edema. Successful revascularization in 1 patient prevented the recurrence of pulmonary edema. In renal allograft recipients who present with unexplained recurrent episodes of acute pulmonary edema, who do not have an obvious cardiac cause, transplant renal artery stenosis should be considered as a possible etiology.
    Nephron 02/1996; 72(2):302-4. · 13.26 Impact Factor
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    ABSTRACT: Our objective was to study the impact of peritoneal catheter configuration on continuous ambulatory peritoneal dialysis (CAPD)-related infections, mechanical complications, and patient dropout in a prospective randomized trial. Forty consecutive patients who were commencing CAPD were randomized to receive either a double-cuff, Swan neck coiled catheter or a double-cuff, straight Tenckhoff catheter, implanted by surgical technique. There was no significant difference in the peritonitis rate between the two groups. There was a lower rate of exit-site infection in the Swan neck group compared to the straight catheter group (0.29 vs 0.60 episodes/patient-year, p < 0.05). Catheter-tip migration occurred in 3 patients with the straight catheters compared to one patient with the Swan neck catheter. No patient had to discontinue CAPD because of mechanical complications. The number of CAPD patient dropouts was not significantly different between the two groups. The Swan neck configuration resulted in a significant reduction in the rate of exit-site infections. The coiled component of the catheter may lead to fewer episodes of catheter-tip migration. However, catheter configuration did not influence the number of technique failures.
    Peritoneal dialysis international: journal of the International Society for Peritoneal Dialysis 01/1996; 16 Suppl 1:S333-5. · 2.21 Impact Factor
  • S O Leong, W C Lye, C C Tan, E J Lee
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    ABSTRACT: Cyclosporine A (CsA) is an important immunosuppressant in kidney transplantation. Acute CsA nephrotoxicity secondary to high drug levels is a well-recognized complication in the immediate posttransplant period. Cyclosporine A is metabolized in the body by the hepatic cytochrome P-450 enzyme system. We present a case of a hypothyroid patient who developed toxic blood CsA levels and acute nephrotoxicity with standard doses of CsA. A reduction of CsA levels led to an improvement of allograft function. Correction of the hypothyroid state resulted in the normalization of CsA requirements, but overcorrection led to an increased requirement of CsA. Thyroid dysfunction should be considered as an interacting factor in the metabolism of CsA.
    American Journal of Kidney Diseases 04/1995; 25(3):503-5. · 5.29 Impact Factor
  • Transplantation Proceedings 03/1995; 27(1):977-8. · 0.95 Impact Factor
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    ABSTRACT: There is an increasing trend towards the use of aminoglycosides in a once-daily dose administration for the treatment of severe infections in nonrenal failure patients. The use of once-daily dose aminoglycoside therapy may be associated with a reduction in toxicity. We performed a prospective randomized study comparing once-daily versus multiple-dose gentamicin in the treatment of continuous ambulatory peritoneal dialysis (CAPD) peritonitis. Seventy-three patients with 100 new episodes of peritonitis were enrolled in the study. At presentation of peritonitis, the patients were alternately assigned to receive either intraperitoneal gentamicin at a dose of 40 mg/2 L dialysate administered as a once-daily dose or gentamicin at a dose of 10mg/2 L dialysate administered 4 times per day. All patients also received intraperitoneal vancomycin at a dose of 1 g per week. There were no significant differences in the treatment success (88% vs 82%, p = NS) and relapse (18% vs 20%, p = NS) rates between the once-daily dose and multiple-dose groups. The mean trough serum gentamicin level was higher in the once-daily dose group compared to the multiple-dose group (0.75 +/- 0.72 vs 1.50 +/- 1.40 mg/L). In conclusion, gentamicin administered in a once-daily dose is as effective as multiple-dose administration in the treatment of CAPD peritonitis. The lower gentamicin level with once-daily dose administration may be associated with a reduction in aminoglycoside toxicity.
    Advances in peritoneal dialysis. Conference on Peritoneal Dialysis 02/1995; 11:179-81.
  • W C Lye, K Hughes, S O Leong, E J Lee
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    ABSTRACT: Dyslipidemia is an important risk factor for atherosclerotic vascular disease. Serum lipoprotein (a) [Lp(a)] has been implicated as an independent atherogenic risk factor. We measured serum (Lp(a) levels in our patients and studied its correlations with other lipoproteins and clinical parameters. All stable patients on continuous ambulatory peritoneal dialysis (CAPD) for more than one month were enrolled in the study. Fasting serum Lp(a), total cholesterol, triglycerides, LDL-cholesterol, HDL-cholesterol, apolipoprotein-A and apolipoprotein-B levels were measured on entering the CAPD program and at 3 monthly intervals. One hundred and nine patients (M/F: 65/44, mean age +/- SD: 59.5 +/- 12.0 years) were studied. Fifty-two patients had diabetes mellitus. Age- and sex-matched normals were used as controls. Serum Lp(a) levels were raised in 54.5% of CAPD patients compared to 18.6% of controls (p < 0.01). There was no significant change in Lp(a) levels over time. Serum Lp(a) levels showed positive and negative correlations with LDL-cholesterol and triglycerides, respectively, but not with age, sex, diabetic status, and serum total cholesterol and albumin levels. Thirty-six of 54 (66.7%) patients with serum Lp(a) levels greater than 30 mg/dL had either coronary, cerebral, and/or peripheral vascular disease compared to 30/55 (54.5%) of patients with serum Lp(a) levels less than 30 mg/dL (p = NS). In conclusion, serum Lp(a) levels were raised in a significant proportion of CAPD patients, but there was no significant association with vascular disease.
    Advances in peritoneal dialysis. Conference on Peritoneal Dialysis 01/1995; 11:131-3.
  • W C Lye, M Kaur, S O Leong, C C Tan, E J Lee
    Transplantation Proceedings 09/1994; 26(4):2026. · 0.95 Impact Factor
  • W C Lye, M Kaur, S O Leong, C C Tan, E J Lee
    Transplantation Proceedings 09/1994; 26(4):2016. · 0.95 Impact Factor
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    ABSTRACT: Skin mast cell density was determined in two age- and sex-matched groups of patients with end-stage renal failure, one with severe uraemic pruritus (n = 9) and the other without (n = 9). In each group, seven patients were on chronic haemodialysis. In uraemic patients without pruritus, skin mast cell density was similar to that in eight healthy controls (40.1 +/- 10.2 mm2 versus 46.5 +/- 20.6 mm2; P = 0.44), a result also obtained when only the patients on haemodialysis were considered (39.3 +/- 14.7 versus 46.5 +/- 20.6; P = 0.46), showing that haemodialysis per se did not cause mast cell proliferation. In contrast, uraemic patients with itch had significantly higher dermal mast cell counts when compared with those without itch (71.8 +/- 36.4 mm2 versus 40.1 +/- 12.9 mm2; P = 0.01). However, there was no difference in serum parathyroid hormone (PTH) and calcium or phosphate concentrations between the two groups. In addition, there was no significant correlation between dermal mast cell density and serum PTH, calcium or phosphate concentrations. These data suggest that uraemic pruritus may be related to mast cell proliferation in the skin.
    Annals of the Academy of Medicine, Singapore 06/1994; 23(3):327-9. · 1.36 Impact Factor
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    ABSTRACT: Staphylococcus aureus nasal carriage has been shown to be associated with an increased risk of S. aureus exit-site infections, but its association with peritonitis is less well established. We performed a four-year prospective study to determine the relationship between S. aureus continuous ambulatory peritoneal dialysis (CAPD)-related infections and nasal carriage. All patients who had been started on CAPD from 1989 to 1992 had regular nose cultures. S. aureus nasal carriage was defined as two of three positive nose cultures. A total of 41 carriers and 105 noncarriers were studied. The rates of S. aureus exit-site infection (0.23 vs 0.09 episode/patient/year, p < 0.005), peritonitis (0.33 vs 0.10 episode/patient/year, p < 0.005), and catheter loss (0.12 vs 0.05, p < 0.01) were significantly higher among the carriers. Life-table analysis showed a significant risk of S. aureus exit-site infection and peritonitis for carriers (p < 0.01). Logistic regression analysis showed that S. aureus nasal carriage was the most important predictive factor for S. aureus peritonitis. In conclusion, our study showed that S. aureus nasal carriage is related to an increased incidence of S. aureus CAPD-related infections.
    Advances in peritoneal dialysis. Conference on Peritoneal Dialysis 02/1994; 10:163-5.
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    Peritoneal dialysis international: journal of the International Society for Peritoneal Dialysis 02/1994; 14(2):174-7. · 2.21 Impact Factor
  • W C Lye, P L Wong, S O Leong, E J Lee
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    ABSTRACT: The identification of organisms is important in the treatment of continuous ambulatory peritoneal dialysis (CAPD) peritonitis. We compared two techniques for isolating organisms in CAPD peritonitis. Clinical and microbiologic data on all episodes of peritonitis from 1991-1993 were prospectively recorded. The isolation of organisms from 77 episodes of peritonitis was done using the conventional centrifugation culture method from 1991-1992; the isolation of organisms from 121 episodes of peritonitis was done using the BACTEC method from 1992-1993. The total culture-positive rates were 75% for the BACTEC technique and 58% for the conventional technique (p = 0.05), with a higher isolation rate for gram-negative organisms (36% vs 18%, p < 0.05). In the isolation of organisms from new episodes of peritonitis, the culture-positive rates were significantly higher for the BACTEC than for the conventional technique (82% vs 55%, p < 0.01). The recovery rates of organisms for both techniques were similar for relapse peritonitis. The treatment outcomes of CAPD peritonitis for the two technique groups, and for the culture-positive and culture-negative groups were not significantly different. In conclusion, the BACTEC method yielded a higher rate of positive cultures for CAPD peritonitis, but did not affect treatment outcome of the infections.
    Advances in peritoneal dialysis. Conference on Peritoneal Dialysis 02/1994; 10:166-8.
  • W C Lye, S O Leong
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    ABSTRACT: Neuromuscular complications, including tetany and laryngeal spasm, are recognized complications of hypocalcemia and hypomagnesemia. We present a continuous ambulatory peritoneal dialysis patient with hypomagnesemia who developed hyperphosphatemia and profound hypocalcemia after oral phosphate replacement for severe hypophosphatemia. The combination of hypocalcemia and hypomagnesemia resulted in life-threatening bilateral vocal cord paralysis. Phosphate replacement should be determined and given cautiously, particularly in patients with renal failure and concomitant electrolyte disturbances.
    American Journal of Kidney Diseases 02/1994; 23(1):127-9. · 5.29 Impact Factor
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    W C Lye, S O Leong
    Peritoneal dialysis international: journal of the International Society for Peritoneal Dialysis 02/1994; 14(4):408-9. · 2.21 Impact Factor
  • W C Lye, P Tambyah, S O Leong, E J Lee
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    ABSTRACT: Tumor markers play an important role in the assessment of patients with some types of malignant tumors. We studied the effects of dialysis and transplantation on the serum levels of five tumor markers; alpha-fetoprotein (AFP), carcino-embryonic antigen (CEA), cancer antigen-125 (CA-125), cancer antigen-19.9 (CA-19.9), and prostate specific antigen (PSA). Serum tumor markers were measured in patients who-had been on dialysis treatment or had a renal transplant for at least one month. Four groups of 30 patients each (hemodialysis, peritoneal dialysis, renal transplant, and normal controls) were studied. Age and sex distribution were comparable between the dialysis and control groups, but the age was significantly younger in the transplant group. Serum AFP and PSA levels were within normal limits in the dialysis and transplant patients. Serum tumor markers, which were raised in the hemodialysis and peritoneal dialysis patients compared to transplant patients and controls, include: CEA (4.5 +/- 2.7 and 5.1 +/- 3.0 vs 1.7 +/- 1.2 and 2.7 +/- 1.2, p < 0.001); CA-125 (41.1 +/- 43.8 and 18.9 +/- 12.7 vs 13.4 +/- 5.7 and 6.1 +/- 4.9, p < 0.001 and p < 0.05); and CA-19.9 (66.0 +/- 60.4 and 66.2 +/- 76.5 vs 20.2 +/- 12.3 and 5.3 +/- 4.5, p < 0.001). Raised CEA, CA-125, and CA-19.9 levels were detected in 37%, 10%, and 53% of peritoneal dialysis patients and 17%, 27%, and 57% of hemodialysis patients. Although the mean serum CEA, CA-125, and CA-19.9 levels were higher in the transplant patients compared to controls.(ABSTRACT TRUNCATED AT 250 WORDS)
    Advances in peritoneal dialysis. Conference on Peritoneal Dialysis 01/1994; 10:109-11.
  • W C Lye, S O Leong, E J Lee
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    ABSTRACT: In view of the increasing concern about methicillin-resistant Staphylococcus aureus (MRSA) infections, we studied the characteristics and outcome of MRSA nasal carriage and infections in our CAPD program. All patients entering into the CAPD program from January 1989 to December 1991 were enrolled into the study. The patients' anterior nares were cultured before the implantation of the catheters. Peritoneal dialysis-related infections were diagnosed based on standard criteria. Data on MRSA nasal carriage, exit-site and tunnel infections and peritonitis were prospectively collected. A total number of 167 patients with 225.9 patient dialysis years were studied with a mean follow-up duration of 16.2 +/- 9.5 months. There were 28 patients with MRSA nasal carriage. The carrier state was unrelated to age, sex and presence of diabetes mellitus. MRSA nasal carriage was associated with a significant increase in the rate of peritonitis (P < 0.01) and exit-site infections (P < 0.01), the number of catheter losses, and CAPD patient dropout (P < 0.001). A total of 30 patients had MRSA infections. In this group, 15 patients had 24 episodes of peritonitis; 20 had 22 episodes of exit-site infections; and 1 had tunnel infection. Fourteen patients had a combination and/or multiple episodes of infections. Treatment of MRSA infections with intraperitoneal vancomycin was unsuccessful in 12 patients (40.0%) resulting in catheter loss. Nine patients (30.0%) dropped out of CAPD after treatment failure for MRSA peritonitis. The patient dropout rate per infection for MRSA infections was comparable to Pseudomonas and fungal infections, but was significantly higher than MSSA infections (P < 0.005).(ABSTRACT TRUNCATED AT 250 WORDS)
    Kidney International 06/1993; 43(6):1357-62. · 8.52 Impact Factor
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    ABSTRACT: Data comparing peritoneal dialysis (PD)-related infection rates between diabetic and nondiabetic patients on chronic peritoneal dialysis are conflicting. We carried out a prospective study comparing PD-related infection rates between diabetic and nondiabetic patients treated with continuous ambulatory peritoneal dialysis (CAPD) in our center. All patients commencing CAPD between January 1989 and June 1992 were enrolled into the study. Patients were followed up until death, CAPD dropout, or until December 1992. Data on diabetes mellitus status, Staphylococcus aureus nasal carriage, and PD-related infections were gathered. Infection rates were analyzed using life tables and the negative binomial test. One hundred and seven diabetic patients and 72 nondiabetic patients were studied. Patients with diabetes mellitus were not at increased risk of being S. aureus nasal carriers. The peritonitis rate was significantly higher in the diabetic group (1.2 vs 0.8 episodes/patient/year, p < 0.05). The exit-site and tunnel infection, catheter loss, and patient dropout rates were not significantly different between the two groups. Life-table analysis did not show a significant difference in the time to first episode of peritonitis and catheter-related infection.
    Advances in peritoneal dialysis. Conference on Peritoneal Dialysis 01/1993; 9:195-7.