Biomedical subjects

Man Ching Law

Publications and source records attributed to Man Ching Law.

7 recordsLinked to original sources

PubMed2007

Continuous ambulatory peritoneal dialysis peritonitis: broth inoculation culture versus water lysis method.

BACKGROUND/AIM: In the setting of empiric antibiotic treatment of peritoneal-dialysis-related peritonitis complications, the speed with which a bacteriological diagnosis can be achieved is of importance. We compare the clinical performance of two culture methods to diagnose the causative microorganisms as suggested by the International Society for Peritoneal Dialysis and the United Kingdom Health Protection Agency. METHODS: We prospectively evaluated microbiological cultures of peritoneal fluid samples by the direct broth culture versus water lysis. Samples from 17 consecutive patients with dialysis-associated peritonitis were examined. RESULTS: Of the 17 dialysates cultured, 14 (82.4%) were positive by one of the two methods. The final culture results agreed in 16 of 17 specimens (94.1%). The preliminary organism identification rate by Gram staining with the broth culture method was 70.6%, which was significantly greater than 17.6% by the water lysis method (p = 0.0019). In particular, the broth culture technique demonstrated superior Gram stain performance to identify Gram-positive organisms. Among the 13 dialysate samples positive by both methods, the broth culture method detected organisms faster than the water lysis method (1.3 +/- 0.7 vs. 2.6 +/- 1.6 days, p = 0.005). CONCLUSIONS: Our results support the routine use of the broth culture technique using BacT/Alert blood culture bottles in order to facilitate early streamlining of empiric antibiotic therapy. Gram staining of sediments after centrifugation is associated with low diagnostic yield. Whether the lysis-centrifugation technique could provide additional value in case of peritonitis with a high likelihood of culture-negative results needs to be evaluated.

Aged↗

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

Antibody response to hepatitis B vaccine in end-stage renal disease patients.

BACKGROUND: This retrospective and comparative study evaluated the relationship between different factors which may contribute to suboptimal immunological response to intramuscular recombinant hepatitis B vaccine in end-stage renal disease (ESRD) subjects. METHODS: From a cohort of 64 dialysis subjects undergoing primary vaccination with Engerix-B, we determined the predictive factors that impinged on patients' response to vaccine, as defined by anti-HBs level > or = 10 mIU/l. Dose efficacy was further evaluated by comparing three historical cohorts vaccinated by the regimens of 20, 40 and 80 microg/dose, respectively. RESULTS: We identified 64 ESRD patients (mean age 43 +/- 12 years, 81% receiving peritoneal dialysis) who received primary vaccination from April 1997 to September 2004. Median follow-up was 6.5 years. They achieved 81% seroconversion rate. Older age, diabetes mellitus, obesity and low Engerix-B dose were risk factors of inadequate anti-HBs response by univariate analysis. By stepwise logistic regression analysis, hepatitis B vaccine dose was the only independent predictive factor of impaired antibody response. An Engerix-B vaccine dose of 20 microg was associated with more than tenfold increase in risk of non-response to hepatitis B vaccine (hazards ratio 32.2 (95% CI 3.85-250.0)). Immunization with 80 microg of Engerix-B increased the likelihood of persistent protective antibody (log-rank test, p = 0.014). Immunization with Engerix-B 80-microg dose is estimated to prevent one extra ESRD subject who would lose seroprotective anti-HBs level at 1 year for every 5.6 patients treated (number needed to treat to benefit, 5.6 (95% CI 5.4-5.8)). CONCLUSIONS: Our results suggest the potential for the three-dose schedule of recombinant vaccine Engerix-B 80 microg to prolong the immune response among ESRD population.

Adult↗

PubMed2005

Impact of social factors on patients on peritoneal dialysis.

BACKGROUND: Clinical outcomes among patients on peritoneal dialysis (PD) might not be linked to medical factors alone. We studied the clinical impact of various social factors among patients on PD. METHODS: In a cohort of 102 consecutive patients who started PD in a single centre between 2003 and 2004, we evaluated the effects of social factors on the development of peritonitis and risk of hospitalization after initiation of PD. RESULTS: Of 102 incident PD patients, 35 subjects (34.3%) were referred to nephrologists more than 3 months before dialysis initiation. During 85.7 patient-years of observation (median follow-up, 10.7 months), four subjects died and six underwent kidney transplantation. Patients receiving social security assistance and those younger than 40 years fared worse than others in terms of their risk of peritonitis. Mean peritonitis-free time for subjects who were on social security assistance was 2.7 months, and for those who were not, 16.4 months (P = 0.045). In the Cox proportional hazards analysis, need for social security assistance and illiteracy were the only statistically significant factors associated with the time to a first peritonitis, after adjustment for social characteristics and relevant coexisting medical factors. Dependence on social security assistance prior to PD was associated with a >2-fold increased likelihood of peritonitis, with an adjusted risk ratio of 2.69 (95% confidence interval, 1.10 to 6.54; P = 0.029). The total number of hospitalization days was similar between those who received social security assistance and those who did not: 17.4+/-14.6 days (range, 4-50 days) vs 17.9+/-14.0 days (range, 0-60 days) (P = 0.89). CONCLUSIONS: Our results confirm that socioeconomic status is closely associated with the rate of peritonitis among PD patients. The long-term reliability of these social predictors remains to be validated.

Adult↗

PubMed2002

Comparison of clinical outcome and ease of handling in two double-bag systems in continuous ambulatory peritoneal dialysis: a prospective, randomized, controlled, multicenter study.

BACKGROUND: We performed a prospective, randomized, controlled, multicenter study on the use of two double-bag disconnect systems: Stay-Safe (SS; Fresenius Deutschland GmbH2) and Ultrabag (UB; Baxter Healthcare, Deerfield, IL) to assess the ease of handling, peritonitis rate, exit-site infection rate, and clinical outcome. METHODS: We enrolled 110 new continuous ambulatory peritoneal dialysis (CAPD) patients; 55 patients were randomized to SS treatment, and 55 patients, to UB treatment. RESULTS: Patients using the UB and SS systems were followed up for 946 and 846 patient-months, respectively. There were 21 episodes of peritonitis in 18 patients in the UB group and 23 episodes in 18 patients in the SS group. No significant difference was observed in peritonitis rates between the two systems, which were 45 and 36.8 patient-months per episode for the UB and SS groups, respectively. At 12 months, 82.1% of patients in the UB group and 72.1% in the SS group were free of peritonitis; at 18 months, 71.1% and 62.2% were free of peritonitis for the UB and SS groups, respectively (P = 0.559). Gram-positive organisms accounted for 28.6% of infections in the UB group and 39.1% in the SS group. Exit-site infection rates were one episode per 21 patient-months versus 19.2 patient-months in the UB and SS groups, respectively (P = 0.743). Patients perceived SS as easier to handle in 4 of the 13 steps immediately post-CAPD training. However, there was no significant difference in rankings between the two systems after 1 month of adaptation. Median training periods were 4 and 5 days for the SS and UB groups, respectively (P = 0.640). CONCLUSION: The two double-bag systems (UB and SS) have similar incidences of peritonitis and exit-site infection. Both systems showed comparably good clinical outcome. The SS system is easier to learn during the initial training period, but the difference is not significant after 1 month's adaptation.

Catheters, Indwelling↗

PubMed2002

Independent effects of residual renal function and dialysis adequacy on dietary micronutrient intakes in patients receiving continuous ambulatory peritoneal dialysis.

BACKGROUND: Dialysis patients are at risk of vitamin and mineral deficiencies, not only because of losses during chronic hemodialysis or peritoneal dialysis but also because of low intakes. OBJECTIVE: The objective was to determine the importance of urea clearance (calculated as K(t)/V) and residual renal function (RRF) in predicting micronutrient intakes in a large cohort of patients receiving continuous ambulatory peritoneal dialysis (CAPD). DESIGN: We conducted a survey of dietary intakes in 242 CAPD patients and divided them into 3 groups according to their weekly urea clearance and RRF: WD group (n = 84), a urea clearance >/= 1.7 and a glomerular filtration rate (GFR) >/= 1 mL x min(-1) x 1.73 m(-2); DD group (n = 71), a urea clearance >/= 1.7 and a GFR < 1 mL x min(-1) x 1.73 m(-2); and ID group (n = 87), a urea clearance < 1.7. RESULTS: Most of the patients had intakes of water-soluble vitamins and minerals that were lower than the recommended dietary allowance; most intakes were significantly higher in the WD group than in the DD and ID groups, except those of niacin and calcium. After age, sex, body weight, and the presence of diabetes were controlled for, total weekly urea clearance and the GFR (but not peritoneal dialysis urea clearance) were significantly associated with intakes of vitamins A and C, the B vitamins, and minerals (calcium, phosphate, iron, and zinc). Low intakes of vitamins and minerals with low RRF and urea clearance were the result of reduced overall food intakes, except for thiamine, vitamin B-6, and folic acid, which were deficient in the diet. CONCLUSIONS: Supplementation with most water-soluble vitamins and minerals, including iron and zinc, should be considered in CAPD patients, especially those with low RRF and low urea clearance. The optimal dose needs to be determined.

Adult↗

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↗