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Bonnie Ching-Ha Kwan

Publications and source records attributed to Bonnie Ching-Ha Kwan.

13 recordsLinked to original sources
PubMed2006

Adherence to peritoneal dialysis training schedule.

BACKGROUND: Shortening behaviour during peritoneal dialysis training can be easily measured, and likened to the skipping behaviour in haemodialysis subjects, although its effect on peritoneal dialysis outcomes is now well understood. We studied the clinical impact of failing to adhere to a peritoneal dialysis training programme among incident dialysis patients. METHODS: This study included 159 consecutive inception peritoneal dialysis patients in a single centre from September 1999 through November 2002. We evaluated the effects of behavioural compliance quantified by the per cent time arriving late for scheduled peritoneal dialysis training. The patients were categorized by whether they arrived late in >20% of their peritoneal dialysis training sessions. RESULTS: Of the 159 incident peritoneal dialysis patients (mean age 57 +/- 13 years) who attended peritoneal dialysis training, 70 subjects (44%) arrived late in >20% of the sessions. They were younger by 5 years than patients who arrived late < or =20%. Mean peritonitis-free time for subjects who arrived late for training in >20% the of sessions was 30.9 months, as compared with 41.8 months in subjects with < or =20% late attendance behaviour (log rank test, P = 0.038). Multivariable Cox proportional hazards analysis showed that late attendance behaviour and baseline serum albumin were the only independent risk factors for the time to a first peritonitis after adjustment for diabetes mellitus and relevant coexisting medical factors. Late arrival in >20% of the peritoneal dialysis training sessions was associated with >50% increased likelihood of subsequent peritonitis, with an adjusted risk ratio of 1.56 (95% confidence interval, 1.02-2.39; P = 0.04). CONCLUSION: These findings show that the behavioural measure of late attendance for peritoneal dialysis training has a crucial role in predicting peritonitis. It may therefore represent a practical strategy for identifying poor adherence or predicting medical outcomes.

Adolescent↗
PubMed2006

Clinical biocompatibility of a neutral peritoneal dialysis solution with minimal glucose-degradation products--a 1-year randomized control trial.

BACKGROUND: Chronic utilization of a bio-incompatible peritoneal dialysis (PD) solution with acidic pH and a high content of glucose degradation product (GDP) has been implicated as a contributing cause of peritoneal failure. We compared a newly formulated solution of neutral pH and low levels of GDP to a standard PD solution. METHODS: Fifty new PD patients were randomized to a conventional lactate-buffered fluid (control) and a pH neutral, lactate-buffered, low GDP solution (balance). Patients were followed for 12 months. Serum samples were assayed for C-reactive protein (CRP). PD effluent was collected and assayed for cancer antigen-125 (CA125) and hyaluronan (HA). Clinical end points were the residual renal function and dialysis adequacy indices. RESULTS: After 52 weeks of treatment, PD fluid CA125 rose from 2.45 +/- 0.96 to 14.30 +/- 2.17 U/ml (P < 0.001), and HA declined from 2.26 +/- 0.60 to 1.45 +/- 0.32 mug/ml (P = 0.07) in the balance group. The balance group had a higher PD fluid CA-125 (14.30 +/- 2.17 vs 7.36 +/- 2.23 U/ml, P = 0.007), lower HA (1.45 +/- 0.32 vs 2.55 +/- 0.32 mug/ml, P = 0.007), and lower serum CRP level (1.77 +/- 0.42 vs 7.73 +/- 2.42 mg/l, P = 0.026) than the control group at 52 weeks. There was no difference in dialysis adequacy indices, ultrafiltration volume, urine output, residual renal function, peritonitis rate or need of hospitalization in 1 year. CONCLUSION: As compared to conventional PD solution, the use of balance, a neutral pH, low GDP solution resulted in a superior profile of PDE mesothelial cell marker and a lower degree of systemic inflammation, and the difference was maintained for 1 year. It remains to be determined whether these effects could result in better long-term clinical outcome.

Biomarkers↗
PubMed2006

Connective tissue growth factor is responsible for transforming growth factor-beta-induced peritoneal mesothelial cell apoptosis.

BACKGROUND: Previous studies found that transforming growth factor-beta (TGF-beta) induces mesothelial production of connective tissue growth factor (CTGF), which may be downstream mediators of TGF-beta. Since high dose TGF-beta induces apoptosis of peritoneal mesothelial cells (PMC), we study the effect of CTGF blockade in the system of TGF-beta-induced PMC apoptosis. METHOD: We examined the effect of TGF-W in primary culture of rat peritoneal mesothelial cells (PMC). PMC apoptosis was studied by flow cytometry. The effect of CTGF was blocked by antibody and short-interfering RNA (siRNA). Expression of apoptotic gene was studied by real-time polymerase chain reaction. RESULT: In cultured unstimulated rat PMC, there is a low but definite incidence of spontaneous apoptosis. Stimulation with TGF-beta 50 pg/ml induces an upregulation of apoptotic gene BAX expression and a downregulation of anti-apoptotic gene BCL-2L expression, and a 4-fold increase in PMC apoptosis. The effect of TGF-beta-induced PMC apoptosis was partly prevented by antibody against CTGF, and completely abolished by CTGF-specific siRNA, while CTGF-blockade by siRNA had no effect on PMC necrosis. CTGF silencing by siRNA prevented the down-regulation of BCL-2L expression induced by TGF-beta, had no effect on the BAX expression. CONCLUSION: Our results indicate that CTGF is an important downstream mediator of TGF-beta-induced PMC apoptosis.

Animals↗
PubMed2006

mRNA expression of target genes in the urinary sediment as a noninvasive prognostic indicator of CKD.

BACKGROUND: Study of messenger RNA (mRNA) expression of target genes in urinary sediment was suggested as a noninvasive marker of renal damage in patients with chronic kidney diseases (CKDs). We studied the relationship between urinary mRNA expression of target genes and risk for renal function deterioration in patients with CKD. METHODS: We studied 131 patients with CKD with kidney biopsy. mRNA expression of 11 target genes in urinary sediment was measured by means of quantitative polymerase chain reaction. Patients then were followed up for 27.4 +/- 10.1 months. The primary end point is doubling of serum creatinine concentration or end-stage renal disease. RESULTS: Thirty-six patients (27.5%) reached the primary end point during follow-up. Univariate analysis showed that sex, age, proteinuria, estimated glomerular filtration rate, histological diagnosis, degree of tubulointerstitial scarring, percentage of glomerulosclerosis, and urinary mRNA expression of hepatocyte growth factor (HGF) were predictors of the primary end point. At 24 months, event-free survival rates were 90.9% and 64.3% for patients with low and high urinary HGF expression, respectively (log rank test, P = 0.002). After adjusting for other confounding factors by using a Cox proportional hazard model, urinary HGF expression remained an independent predictor of the primary end point, and a 1-fold increase in expression was associated with a 4.0% (95% confidence interval, 0.5 to 7.5; P = 0.024) increase in risk. CONCLUSION: In the target genes examined, urinary HGF expression is an independent prognostic indicator of CKD after adjusting for confounding clinical and histological factors. Measurement of urinary HGF mRNA expression may be a useful noninvasive tool for risk stratification of patients with CKD.

Biopsy↗
PubMed2005

Hypokalemia in Chinese peritoneal dialysis patients: prevalence and prognostic implication.

BACKGROUND: Abnormal potassium metabolism may contribute to the increased cardiac morbidity and mortality seen in dialysis patients. We studied the pattern of serum potassium levels in a cohort of Chinese peritoneal dialysis (PD) patients. METHODS: We studied serum potassium levels of 266 PD patients during 3 consecutive clinic visits. Dialysis adequacy, residual renal function, and nutritional status also were assessed. Patients were followed up for 33.7 +/- 20.7 months. RESULTS: Mean serum potassium level was 3.9 +/- 0.5 mEq/L (mmol/L). Five patients (1.9%) had an average serum potassium level less than 3 mEq/L (mmol/L), whereas 54 patients (20.3%) had a serum potassium level less than 3.5 mEq/L (mmol/L). Serum potassium levels correlated with overall Subjective Global Assessment score (r = 0.276; P < 0.001) and serum albumin level (r = 0.173; P = 0.005) and inversely with Charlson comorbidity score (r = -0.155; P = 0.011). There was no correlation between serum potassium level and daily PD exchange volume, total Kt/V, urine volume, or residual glomerular filtration rate. By means of multivariate analysis with Cox proportional hazard model to adjust for confounders, serum potassium level was an independent predictor of actuarial patient survival. PD patients with hypokalemia (serum potassium < 3.5 mEq/L [mmol/L]) had significantly worse actuarial survival (hazard ratio, 1.79; 95% confidence interval, 1.12 to 2.85; P = 0.015) than those without hypokalemia after adjusting for confounding factors. CONCLUSION: Hypokalemia is common in Chinese PD patients. Serum potassium level was associated with nutritional status and severity of coexisting comorbid condition. Furthermore, hypokalemia was an independent predictor of survival in PD patients. Additional studies may be needed to investigate the benefit of potassium supplementation for PD patients with hypokalemia.

Adult↗
PubMed2005

Prevalence of silent kidney disease in Hong Kong: the screening for Hong Kong Asymptomatic Renal Population and Evaluation (SHARE) program.

BACKGROUND: End-stage renal disease (ESRD) is epidemic worldwide. In Hong Kong, the annual incidence of ESRD has risen from 100 pmp (per million population) in 1996 to 140 pmp in 2003. SHARE (Screening for Hong Kong Asymptomatic Renal Population and Evaluation program) is a population-based screening program aimed at identifying the prevalence of unrecognized renal disease in asymptomatic individuals, allowing further evaluation and disease-modifying interventions. METHODS: From November to December 2003, SHARE was conducted in several large residential communities in Hong Kong. The screening tool included a questionnaire documenting demographics and history or family history of diabetes mellitus (DM), hypertension (HT), and chronic kidney disease (CKD), together with on-site measurements of blood pressure (BP) and urine dipstick for protein, blood, and glucose. RESULTS: There were a total of 1811 participants. One thousand two hundred and one subjects were entered into the final analysis. Among the 1201 who were apparently "healthy" (asymptomatic and without history of DM, HT, or CKD), the prevalence of positive (> or =1+) urine dipstick for protein, glucose, blood, protein or blood, any urine abnormality, and HT (BP> or =140/90) was 3.2%, 1.7%, 13.8%, 16%, 17.4%, and 8.7%, respectively. Thirty three percent of the age over 60 years old group had either hypertension or urine abnormalities, compared with 24.0% in the 41- to 60-year-old group and 9.7% in the 20- to 40-year-old group. Having a family history of diabetes or hypertension increases the risk of having urine abnormalities, while a family history of hypertension also increases the risk of high blood pressure. CONCLUSION: It is concluded that subclinical abnormalities in urinalysis or BP readings are prevalent across all age groups in the adult population. An effective screening program at the primary care level that identifies these subjects for further evaluation is warranted, and the public in Hong Kong should be educated toward the significance of such findings in order to have regular health check for asymptomatic renal diseases.

Adult↗
PubMed2004

Severe acute respiratory syndrome in dialysis patients.

Reviewed are the clinical features and outcome of 12 chronic dialysis patients (six men) who contracted severe acute respiratory syndrome (SARS) compared with 23 sex- and age-matched nonuremic SARS patients as controls. Eight were on peritoneal dialysis (PD) and four on hemodialysis. Mean age was 58 +/- 12 yr for the dialysis patients, and 57 +/- 12 yr for the controls. The presenting symptoms of dialysis patients were similar to the controls. With appropriate protection measures, hemodialysis was performed in a dedicated area of the SARS isolation ward, while PD was continued as intermittent PD. In all seven patients with PD effluent tested, SARS-related coronavirus (CoV) could not be identified by polymerase chain reaction (PCR) or viral culture. Three dialysis patients had persistent positive stool PCR after 5 wk, whereas all nondialysis patients had negative stool PCR after 1 wk. Despite dosage adjustment, ribavirin-induced hemolytic anemia was more severe in the dialysis patients. Dialysis patients required longer hospitalization than the controls, but the mortality was similar. With appropriate protective measures, dialysis could be safely performed. Dialysis patients with SARS often require prolonged hospitalization. Furthermore, these patients may have an extended period of viral shedding, which should be carefully monitored for the purpose of infection control.

Aged↗
PubMed2004

Clinical studies of thiazide-induced hyponatremia.

To determine the prevalence and vulnerability of symptoms from thiazide-induced hyponatremia, we reviewed 223 cases of symptomatic hyponatremia enrolled between January 1996 and April 2002. There was a high frequency of neurologic manifestation of thiazide-induced hyponatremia, whereas clinical dehydration was not a discernible feature. Female patients presented with lower serum sodium levels than male counterparts (114+/-8 versus 117+/-8 mmol/L, P=0.02), although the frequency of central nervous system manifestation was comparable between two gender groups. The most frequent symptoms were malaise and lethargy (49%), followed by dizzy spells (47%) and vomiting (35%). Degree of hyponatremia upon presentation predicted the development of confusion and vomiting symptoms. Serum sodium concentration < or =115 mmol/L was significantly associated with the development of confusion (odds ratio 2.6, 95% confidence interval 1.3 to 5.1, P=0.004). Our results show that symptoms from thiazide-induced hyponatremia primarily reflect osmotic water shift into brain cells rather than extracellular fluid volume depletion.

Aged↗
PubMed2003

Severe acute respiratory syndrome in a hemodialysis patient.

Severe acute respiratory syndrome (SARS) is a highly infective disease caused by a newly identified coronavirus. We described the clinical course of the first long-term hemodialysis patient who developed SARS in the literature, and our experience in performing hemodialysis for this patient. Such patients may present with a less typical clinical picture, making diagnosis difficult. In this patient, the course of disease and duration of viral shedding was apparently prolonged, thus highlighting the need for increased infection control. Despite worsening the anemia in renal failure patients by causing hemolysis, ribavirin is well tolerated after dosage adjustment. Difficulties of diagnosis, infection control, and treatment of SARS in renal failure patients are discussed in this report.

Adult↗
PubMedDate not supplied

Cefazolin plus ceftazidime versus imipenem/cilastatin monotherapy for treatment of CAPD peritonitis--a randomized controlled trial.

BACKGROUND: Peritonitis is a serious complication of peritoneal dialysis (PD). We studied the efficacy of imipenem/cilastatin monotherapy in the treatment of PD-related peritonitis. METHODS: We performed an open-label, randomized control study comparing imipenem/cilastatin monotherapy (treatment group) versus cefazolin plus ceftazidime (control group) in the treatment of PD peritonitis. The result was further compared to a historic group treated with cefazolin plus netilmycin. Outcome measures were primary response rate at day 10 and complete cure rate. RESULTS: We enrolled 51 patients in the treatment group, 51 in the control group, and identified 96 in the historic group. The primary response rate to the assigned antibiotics was 49.0%, 51.0%, and 49.0% for the treatment, control, and historic groups, respectively (p = 0.97). The primary response rate allowing for change in antibiotic was 82.4%, 90.2%, and 82.3%, respectively, for the three groups (p = 0.41). The complete cure rate was 72.5%, 80.4%, and 82.3%, respectively (p = 0.60). Tenckhoff catheter removal was needed in 6 cases in the treatment group, 6 cases in the control group, and 13 cases in the historic group (p = 0.90). CONCLUSIONS: We concluded that monotherapy of imipenem/cilastatin has similar efficacy compared to the two standard regimens of cefazolin plus ceftazidime or netilmycin in the treatment of PD peritonitis.

Cefazolin↗
PubMedDate not supplied

A risk analysis of continuous ambulatory peritoneal dialysis-related peritonitis.

OBJECTIVE: We studied the clinical characteristics that influence the risk of dialysis-related peritonitis complication in incident Chinese patients undergoing continuous ambulatory peritoneal dialysis (CAPD). METHODS: A single center, retrospective, observational cohort study was carried out to examine the risk factors of developing a first episode of dialysis-related peritonitis. RESULTS: Between 1995 and 2004, 246 incident CAPD patients were recruited for analysis. During the study period of 897.1 patient-years, 85 initial episodes of peritonitis were recorded. The median peritonitis-free time for diabetic subjects was significantly worse than for nondiabetic subjects (49.0 +/- 10.5 vs 82.3 +/- 12.6 months, p = 0.0019). The difference was due mainly to a higher likelihood of developing peritonitis with gram-negative organisms in patients with diabetes mellitus (p = 0.038). Low serum albumin concentration was also associated with worse peritonitis-free survival. There was a nonsignificant trend toward an increased risk for peritonitis in the group of patients with cerebrovascular disease. According to multivariate Cox proportional hazards model for the analysis of time to first peritonitis episode, the two independent risk factors were presence of diabetes mellitus and initial serum albumin concentration. In particular, diabetes mellitus was associated with a hazard ratio of 1.50 and a 95% confidence interval of 1.05 - 2.40 (p = 0.030) to develop an initial peritonitis. Lower serum albumin level at the start of CAPD was a significant predictor of peritonitis, with hazard ratio of 1.67 for every decrease of 10 g/L, and 95% confidence interval 1.08 - 2.60 (p = 0.021). CONCLUSIONS: Our results confirm the susceptibility of diabetic CAPD and hypoalbuminemic patients to peritonitis, and highlight the role of further studies in reducing this complication.

Adolescent↗
PubMedDate not supplied

Peritoneal albumin excretion is a strong predictor of cardiovascular events in peritoneal dialysis patients: a prospective cohort study.

BACKGROUND: Microalbuminuria is a marker of systemic endothelial dysfunction. We hypothesize that peritoneal albumin excretion in peritoneal dialysis (PD) patients, which is conceptually analogous to microalbuminuria in non-uremic patients, can predict cardiovascular disease in new PD patients. METHOD: We studied peritoneal albumin excretion in 43 new PD patients. They were then followed prospectively for the development of cardiovascular events. All-cause mortality and duration of hospitalization for cardiovascular diseases were also recorded. RESULT: The average duration of follow-up was 26.5 +/- 17.6 months. During the follow-up period, 15 patients developed cardiovascular events. Event-free survival at 36 months was 81.4% and 53.6% for low (< 300 mg/L) and high (> 300 mg/L) peritoneal albumin excretion groups respectively (log rank test, p = 0.042). By Cox regression analysis, the only independent factors for event-free survival were diabetic status and peritoneal albumin excretion rate. For every 100 mg/L increase in peritoneal albumin excretion, the adjusted hazard ratio of developing a cardiovascular event was 1.83 [95% confidence interval (CI) 1.11 - 3.02, p = 0.018]. Actuarial patient survival at 36 months was 85.7% and 59.1% for low and high peritoneal albumin excretion groups respectively (log rank test, p = 0.10). After adjusting for the duration of follow-up for individual patients, the average duration of hospitalization was 9.1 +/- 16.2 and 21.7 +/- 25.7 days per year of follow-up for low and high peritoneal albumin excretion groups respectively (Mann-Whitney U test, p = 0.012). CONCLUSION: Although the sample size of our present study is small and does not have adequate statistical power, we conclude that peritoneal albumin excretion may be an important predictor of cardiovascular disease. Further studies are needed to examine the role of dialysate albumin excretion as a means of cardiovascular risk stratification in PD patients.

Adult↗