Arterial pulse wave velocity and peritoneal transport characteristics independently predict hospitalization in Chinese peritoneal dialysis patients.

OBJECTIVE: Cardiovascular disease (CVD) is the most common cause of mortality in chronic peritoneal dialysis (PD) patients. Increased arterial stiffness may be related to a high peritoneal permeability resulting in fluid overload in PD patients. We studied the relations between arterial stiffness, peritoneal transport, and radiographic parameters of systemic fluid overload in a cohort of Chinese PD patients. DESIGN: Prospective cohort study. SETTING: University referral center. PATIENTS: We studied 107 PD patients. Vascular pedicle width and cardiothoracic ratio were measured from a plain postero-anterior chest radiograph. Pulse wave velocity (PWV) was determined at carotid-femoral (C-F) and carotid-radial sites. Peritoneal transport was determined by the dialysate-to-plasma ratio (D/P) of creatinine at 4 hours of dwell. Patients were followed for 9.4 +/- 4.6 months. OUTCOME MEASURES: Duration of hospitalization; actuarial and technique survival. RESULTS: There were no relationships between radiographic measures, arterial PWV, and D/P creatinine. However, both C-F PWV and D/P creatinine were independent predictors of the number of hospitalizations for CVD. None of the parameters correlated with mortality in this study. CONCLUSIONS: There were no relationships between radiological parameters of fluid overload, peritoneal transport characteristics, and arterial PWV. Both C-F PWV and D/P creatinine were independent predictors of the number of hospitalizations for CVD. Our result suggests that arterial stiffness and high peritoneal transport each contribute to the development of CVD in this group of patients.

Endotoxemia is associated with better clinical outcome in incident Chinese peritoneal dialysis patients: a prospective cohort study.

BACKGROUND: Endotoxemia is common in peritoneal dialysis (PD) patients; circulating lipopolysaccharide (LPS) level is related to the degree of systemic inflammation and atherosclerosis. We examine whether baseline plasma LPS level represents a prognostic marker in new PD patients. METHODS: We studied 158 new Chinese PD patients (80 males). Baseline plasma LPS level at initiation of PD was measured. Patients were stratified into quartiles according to plasma LPS level: quartile I, <0.45 EU/mL; II, 0.45 - <0.70 EU/mL; III, 0.70 - <0.95 EU/mL; and IV, ≥ 0.95 EU/mL. The patients were then prospectively followed for the development of cardiovascular events. All-cause mortality and duration of hospitalization were also recorded. RESULTS: Average age was 55.6 +/- 14.7 years; average endotoxin concentration was 0.70 +/- 0.30 EU/mL; average follow-up was 55.5 +/- 36.9 months. At 60 months, event-free survival was 41.0%, 52.5%, 65.0%, and 61.5% for LPS level quartiles I, II, III, and IV, respectively (log rank test p = 0.066). By multivariate analysis with the Cox proportional hazard model to adjust for confounders, plasma LPS level had no independent effect. At 60 months, technique survival was 20.5%, 20.0%, 32.5%, and 51.3% for LPS level quartiles I, II, III, and IV, respectively (log rank test p = 0.0009). By Cox proportional hazard model, each higher quartile of LPS conferred 28.6% protection (95% confidence interval 15.6% - 40.3%, p = 0.0002) from developing technique failure. A higher plasma LPS level had a lower all-cause mortality (unadjusted hazard ratio 0.486, p = 0.046) and cardiovascular mortality (unadjusted hazard ratio 0.251, p = 0.025), but the result became insignificant after adjusting for potential confounders. CONCLUSION: A higher baseline plasma LPS level is an independent predictor of better technique survival in new Chinese PD patients, with an insignificant trend of fewer cardiovascular events. The observation seems to conform to the phenomenon of reverse epidemiology for other traditional cardiovascular risk factors in dialysis patients but the exact reason for this paradoxical phenomenon requires further investigation.

Recurrent and relapsing peritonitis: causative organisms and response to treatment.

BACKGROUND: The clinical behavior and optimal treatment of relapsing and recurrent peritonitis episodes in patients undergoing long-term peritoneal dialysis are poorly understood. STUDY DESIGN: Retrospective study over 14 years. SETTING & PARTICIPANTS: University dialysis unit; 157 relapsing episodes (same organism or culture-negative episode occurring within 4 weeks of completion of therapy for a prior episode), 125 recurrent episodes (different organism, occurs within 4 weeks of completion of therapy for a prior episode), and 764 control episodes (first peritonitis episode without relapse or recurrence). PREDICTORS: Exit-site infection, empirical antibiotics. OUTCOME MEASURES: Primary response (resolution of abdominal pain, clearing of dialysate, and peritoneal dialysis effluent neutrophil count < 100 cells/mL after 10 days of antibiotic therapy), complete cure (resolution by using antibiotics without relapse/recurrence), catheter removal (for any cause while on antibiotic therapy), and mortality. RESULTS: Compared with the control group, more relapsing episodes were caused by Pseudomonas species (16.6% versus 9.4%) and were culture negative (29.9% versus 16.4%); recurrent infections commonly were caused by Enterococcus species (3.2% versus 1.2%) or other Gram-negative organisms (27.2% versus 11.1%) or had mixed bacterial growth (17.6% versus 12.7%). There were significant differences in primary response, complete cure, and mortality rates among groups (P < 0.001 for all comparisons). Compared with the control and relapsing groups, post hoc analysis showed that the recurrent group had a significantly lower primary response rate (86.4%, 88.5%, and 71.2%, respectively), lower complete cure rate (72.3%, 62.4%, and 42.4%, respectively), and higher mortality rate (7.7%, 7.0%, and 20.8%, respectively). LIMITATIONS: Retrospective analysis. CONCLUSION: Relapsing and recurrent peritonitis episodes are caused by different spectra of bacteria and probably represent 2 distinct clinical entities. Recurrent peritonitis episodes had a worse prognosis than relapsing ones.

Longitudinal changes of cardiothoracic ratio and vascular pedicle width as predictors of volume status during one year in Chinese peritoneal dialysis patients.

BACKGROUND: Volume overload is an important contributing factor of cardiovascular disease (CVD) in peritoneal dialysis (PD) patients. Vascular pedicle width (VPW) and cardiothoracic ratio (CTR) in routine chest radiograph are indicators of intravascular volume. Longitudinal changes of VPW and CTR may be important prognostic factors of PD patients. METHOD: We studied 212 PD patients. Longitudinal changes in VPW (DeltaVPW) and CTR (DeltaCTR) were calculated. The relationship between radiologic measurements and clinical outcome was analyzed. RESULTS: During the 12 months prior to enrollment, VPW rose from 53.35 +/- 5.66 to 55.40 +/- 6.30 mm (p < 0.001) and CTR rose from 53.3 +/- 7.1 to 56.0 +/- 7.8% (p < 0.001). After adjusting for confounding variables by Cox regression model, DeltaCTR is an independent predictor of hospitalization-free survival; 1% increase in CTR confers 2.9% higher risk of hospitalization (95% confidence interval 0.2-5.7%, p = 0.034). None of the radiologic measurements correlated with actuarial patient survival. CONCLUSIONS: In chronic PD patients, DeltaCTR is an independent predictor of hospitalization-free survival. This simple radiological parameter may serve as an important parameter for the risk stratification of PD patients.

Factors associated with sudden death in peritoneal dialysis patients.

BACKGROUND: Relatively little is known of the epidemiology and predictors of sudden death in peritoneal dialysis (PD) populations. We aimed to identify the risk factors of sudden death among PD subjects. METHODS: To explore clinical correlates of sudden death in PD patients, we conducted a population-based case-control study using data from a single dialysis unit. Cases (n=24) were defined as all PD patients that met the criteria for sudden death during January 2003 through December 2006. We also selected 48 control subjects that were selected from the prevalent PD patient name list compiled in alphabetical order. Data on the hemoglobin, potassium, and calcium levels, residual renal function, dialysis adequacy, cardiovascular risks, comorbid conditions, concurrent use of aspirin, beta-blockers, angiotensin-converting enzyme inhibitors, and erythropoietin, electrocardiographic and echocardiographic findings were extracted from case notes and computer records. Confounders were controlled by logistic regression. RESULTS: Over a period of 4 years, 24 PD patients (mean age 61.4+/-9.5 years, median duration of dialysis 3.1 years) experienced sudden death. Univariate analyses showed that patients that died suddenly were more likely to be male and to have diabetes mellitus, a history of smoking, and a lower small solute clearance as measured by Kt/V. Cases of sudden death were also more likely to have received blood transfusion within the previous 1 year. There were no significant differences between patients and controls for residual renal function, serum potassium levels, control of blood pressure and mineral metabolism, or hemoglobin levels. Multivariate regression analysis confirmed independent association between recent blood transfusion and increased odds of sudden death [adjusted odds ratio (OR) 5.18, 95% confidence interval (CI) 1.44-18.6]. Two other factors significantly associated with risk of sudden death were male gender (adjusted OR 4.16, 95% CI 1.14-15.2) and diabetes mellitus (adjusted OR 5.33, 95% CI 1.53-18.6). CONCLUSION: This study shows that recent blood transfusion is associated with an increased likelihood of sudden death in PD patients. The mechanisms that underlie this observation are unclear.

The impact of social support on the survival of Chinese peritoneal dialysis patients.

BACKGROUND: Social support is an independent risk factor for mortality among new hemodialysis patients. We evaluated the effect of social support on the outcome of Chinese peritoneal dialysis (PD) patients. METHODS: We studied 167 prevalent PD patients. They completed the Medical Outcomes Study Social Support Survey, Chinese Version (MOS-SSS-C) questionnaire. Patients were followed for 1 year. Outcome measures included change in nutritional status, hospitalization, and technique and actuarial patient survival. RESULTS: Actuarial survival was 57.1%, 72.7%, 85.3%, and 88.6% for MOS-SSS-C total score quartiles I, II, III, and IV, respectively (log rank test, p = 0.037). Technique survival was 57.1%, 81.9%, 91.9%, and 91.4% (log rank test, p = 0.0044). By multivariate analysis with the Cox proportional hazard model to adjust for confounders, every 1 point increase in MOS-SSS-C total score was associated with a 0.6% [95% confidence interval (CI) 0.2%-0.9%, p = 0.003] reduction in the risk of death and a 0.5% (95%CI 0.1%-1.0%, p = 0.037) reduction in the risk of technique failure. The MOS-SSS-C score had no significant effect on change in nutritional or dialysis adequacy indices, hospitalization, or number of peritonitis episodes in 1 year. CONCLUSION: The degree of social support is an important predictor of actuarial and technique survival in Chinese PD patients. Measures to enhance social support may represent an easily achievable means of improving the clinical outcome of PD patients.

The relationship between bone morphogenic protein-7 and peritoneal transport characteristics.

BACKGROUND: After prolonged peritoneal dialysis (PD) and exposure to a non-physiological dialysis solution, peritoneal mesothelial cells undergo the epithelial-to-mesenchymal transition. In other biological systems, bone morphogenic protein-7 (BMP-7) is a key factor that controls this process. However, the role of BMP-7 in peritoneal physiology has not been studied. METHODS: We studied the peritoneal transport characteristics of 50 consecutive new PD patients at 4 and 52 weeks after PD. Peritoneal permeability will be determined by the standard peritoneal equilibration test (PET). BMP-7 in PD effluent (PDE) at mRNA and protein level at 4 weeks was quantified. RESULTS: At 4 weeks, the mRNA expression of BMP-7 in PDE significantly correlated with peritoneal transport characteristics, including the dialysate-to-plasma creatinine ratio at 4 h (D/P4) (r = 0.422, P = 0.015) and mass transfer area coefficient (MTAC) of creatinine (r = 0.457, P = 0.008). The PDE BMP-7 level by ELISA also had marginal correlation with D/P4 (r = 0.287, P = 0.072) and MTAC creatinine (r = 0.287, P = 0.073), although the result did not reach statistical significance. For the subgroup of patients who remained free of peritonitis, the PDE BMP-7 level by ELISA had significant correlation with the change in D/P4 (r = 0.441, P = 0.017) and MTAC creatinine in 52 weeks (r = 0.415, P = 0.025). The PDE BMP-7 level remained independently associated with the change in peritoneal transport adjusting for age, sex, serum C-reactive protein and PDE transforming growth factor-beta level. In patients who had peritonitis during the study period, the PDE BMP-7 level did not affect the change in peritoneal transport. Conclusion. We find that the peritoneal BMP-7 level correlates with peritoneal transport characteristics, and a high PDE BMP-7 level is associated with a gradual increase in peritoneal transport parameters with time. It remains unclear, however, whether this effect is beneficial, and the therapeutic role of exogenous BMP-7 on peritoneal transport requires a further study.

Oral calcitriol for the treatment of persistent proteinuria in immunoglobulin A nephropathy: an uncontrolled trial.

BACKGROUND: Laboratory research and previous retrospective study suggest that vitamin D and its analogues have profound effects on immune system function and glomerular mesangial cell proliferation. We conducted an open-label study to evaluate the antiproteinuric effect of calcitriol on proteinuria in patients with immunoglobulin A (IgA) nephropathy. STUDY DESIGN: Open-label prospective uncontrolled trial. SETTING & PARTICIPANTS: 10 patients (3 men) with biopsy-proven IgA nephropathy and persistent proteinuria despite angiotensin-converting enzyme-inhibitor or angiotensin receptor blocker therapy in a tertiary referral center. INTERVENTION: Calcitriol, 0.5 microg, twice weekly for 12 weeks. OUTCOME MEASURES: Changes in proteinuria, renal function, serum transforming growth factor beta (TGF-beta) and angiotensin II levels. RESULTS: After calcitriol treatment, there was a significant overall decrease in proteinuria with time by using a general linear model with repeated measures (P = 0.03). There was a progressive decrease in urine protein-creatinine ratio from 1.98 +/- 0.74 to 1.48 +/- 0.81 g/g (P = 0.007) during the first 6 weeks that persisted throughout the study period. No significant change in blood pressure or renal function was noted. There was a simultaneous decrease in serum TGF-beta level, and percentage of decrease in serum TGF-beta level significantly correlated with percentage of change in proteinuria (Spearman r = 0.643; P = 0.02). Serum angiotensin II level did not change throughout the study. One patient experienced transient hypercalcemia that normalized after a dosage decrease. No other major adverse effect was reported. LIMITATIONS: This small study is uncontrolled and does not examine the long-term effect of calcitriol therapy. CONCLUSION: Twice-weekly oral calcitriol has a modest antiproteinuric effect in patients with IgA nephropathy and persistent proteinuria despite angiotensin-converting enzyme-inhibitor or angiotensin receptor blocker therapy. Additional studies are needed to confirm the renal protecting effect of calcitriol in patients with chronic proteinuric kidney diseases.

Endotoxemia is related to systemic inflammation and atherosclerosis in peritoneal dialysis patients.

BACKGROUND AND OBJECTIVES: Systemic inflammatory state is a hallmark of peritoneal dialysis (PD) patients, but its etiology remains obscure. Because circulating microbial products are an important cause of systemic immune activation in other conditions such as HIV infection, it was hypothesized that endotoxemia is a cause of systemic inflammatory state and atherosclerosis in PD patients. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Plasma lipopolysaccharide (LPS) levels in 30 consecutive new PD patients were measured. The result was compared with serum C-reactive protein (CRP) level, peritoneal transport status, history of pre-existing cardiovascular diseases, and carotid intima media thickness (IMT) by Doppler ultrasound. RESULTS: Among the 30 PD patients, there were 17 men. The average age was 53.7 +/- 15.1 yr. The average endotoxin concentration of PD patients was 0.44 +/- 0.18 EU/ml, which was significantly higher than that of patients with chronic kidney disease secondary to Ig-A nephropathy (IgAN) (0.035 +/- 0.009 EU/ml, P < 0.0001) and the controls (0.013 +/- 0.007 EU/ml, P < 0.0001). In PD patients, plasma LPS concentration had a significant correlation with serum CRP (r = 0.415, P = 0.025) and serum albumin level (r = -0.394, P = 0.034). In contrast, plasma LPS level did not correlate with Charlson's Comorbidity Index, peritoneal transport characteristics, or nutritional indices. Patients with pre-existing cardiovascular disease (CVD) had higher plasma LPS level than those without CVD (0.53 +/- 0.19 versus 0.36 +/- 0.16 EU/ml, P = 0.016). Plasma LPS level correlated with carotid IMT (r = 0.438, P = 0.016). CONCLUSIONS: It was found that endotoxemia was probably common in PD patients, and the degree of circulating endotoxemia might be related to the severity of systemic inflammation and features of atherosclerosis. This result suggests that endotoxemia may have a contributory role to the systemic inflammatory state and accelerated atherosclerosis in PD patients.

Coagulase negative staphylococcal peritonitis in peritoneal dialysis patients: review of 232 consecutive cases.

BACKGROUND AND OBJECTIVES: Coagulase-negative Staphylococcus species is the most common cause of peritoneal dialysis-related peritonitis; however, the optimal treatment strategy of coagulase-negative Staphylococcus species peritonitis remains controversial. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: All of the coagulase-negative Staphylococcus species peritonitis in a dialysis unit from 1995 to 2006 were reviewed. During this period, there were 2037 episodes of peritonitis recorded; 232 episodes (11.4%) in 155 patients were caused by coagulase-negative Staphylococcus species. RESULTS: The overall primary response rate was 95.3%; the complete cure rate was 71.1%. Patients with a history of recent hospitalization or recent antibiotic therapy had a higher risk for developing methicillin-resistant strains. Episodes that were treated initially with cefazolin or vancomycin had similar primary response rate and complete cure rate. There were 33 (14.2%) episodes of relapse and 29 (12.5%) episodes of repeat peritonitis; 12 (60.6%) of the repeat episodes developed within 3 mo after completion of antibiotics. Relapse or repeat episodes had a significantly lower complete cure rate than the other episodes. For relapse or repeat episodes, treatment with effective antibiotics for 3 wk was associated with a significantly higher complete cure rate than the conventional 2-wk treatment. CONCLUSIONS: Coagulase-negative Staphylococcus species peritonitis remains a common complication of peritoneal dialysis. Methicillin resistance is common, but the treatment outcome remains favorable when cefazolin is used as the first-line antibiotic. A 3-wk course of antibiotic can probably achieve a higher cure rate in relapse or repeat episodes.

Continuous ambulatory peritoneal dialysis is better than automated peritoneal dialysis as first-line treatment in renal replacement therapy.

This article examines the roles of continuous ambulatory peritoneal dialysis (CAPD) versus automated peritoneal dialysis (APD) as first-line renal replacement therapy. To date, no high-quality large-scale randomized controlled studies have compared CAPD with APD as first-line therapy. However, a discussion on this issue is important so that nephrologists can decide and patients can have a choice of modality on which to start dialysis, especially in the context of health care economics. We review the literature and present Hong Kong as the model of a "CAPD first" policy, an appealing, cost-effective approach for any country. An ideal renal replacement therapy should provide optimal survival, lowest possible risk for comorbidity, highest level of quality of life, and equally important, acceptable cost to society. When we consider this subject in the context that all patients should be started on one first-line modality, the data suggest that a "CAPD first" policy has all these advantages, with APD probably having the edge only with regard to patient preference. The present review highlights preservation of residual renal function, removal and balancing of sodium, incidence of peritonitis, peritoneal membrane transport status, patient rehabilitation, and financial issues in demonstrating that a "CAPD first" policy is the model that should be adopted.

Good patient and technique survival in elderly patients on continuous ambulatory peritoneal dialysis.

The aging population has significant implications for the community. The increasing number of elderly end-stage renal disease (ESRD) patients presses the renal team to find an appropriate management plan. We used a retrospective analysis to study the effectiveness of continuous ambulatory peritoneal dialysis (CAPD) in elderly ESRD patients. Of the 328 CAPD patients recruited for the study, 121 were in the elderly group (>or=65 years of age), and 207 were in the control group (under 65 years of age). Median age in the elderly group was 71 years, and in the control group, 51 years. The elderly group had a higher prevalence (54.5%) of diabetes mellitus. The 2-year and 5-year rates of patient survival were 89.3% and 54.8% respectively in the elderly group and 92.2% and 62.9% in the control group (p=0.19). The 2-year and 5-year rates of technique survival were 84.0% and 45.7% respectively in the elderly group and 80.9% and 49.1% in the control group (p=0.75). The probability of a 12-month peritonitis-free period was 76.6% in the elderly group and 76.5% in the control group (p=0.75). One hundred elderly patients (82.6% of the group) performed their CAPD exchanges by themselves. We observed no significant difference in clinical outcome-including patient survival, technique survival, and peritonitis-free period-between the elderly self-care CAPD and the elderly assisted CAPD groups. In elderly ESRD patients, CAPD is an effective dialysis modality. A slightly longer training time is to be expected for elderly patients. Self-care CAPD for elderly patients who are capable of performing their own exchanges provides them with an independent home life.

Staphylococcus aureus peritonitis complicates peritoneal dialysis: review of 245 consecutive cases.

Peritonitis that is caused by Staphylococcus aureus is a serious complication in peritoneal dialysis (PD), but the clinical course of PD-related S. aureus peritonitis remains unclear. All of the S. aureus peritonitis in a dialysis unit from 1994 to 2005 were reviewed. During this period, 2065 episodes of peritonitis were recorded; 245 (11.9%) episodes in 152 patients were caused by S. aureus and 45 (18.4%) episodes were caused by methicillin-resistant S. aureus (MRSA). Patients with a history of recent hospitalization had a higher risk for isolation of MRSA than the others (30.6 versus 14.2%; P = 0.004). The overall primary response rate was 87.8%; the complete cure rate was 74.3%. However, 21 (8.6%) episodes developed relapse and 59 (24.1%) developed repeat S. aureus peritonitis. Episodes that were caused by MRSA had a lower primary response rate (64.4 versus 93.0%; P < 0.001) and complete cure rate (60.0 versus 77.5%; P = 0.023) than the others. Episodes that were treated initially with vancomycin had better primary response rate than those that were treated with cefazolin (98.0 versus 85.2%; P = 0.001), but the complete cure rate was similar. Adjuvant rifampicin treatment was associated with a significantly lower risk for relapse or repeat S. aureus peritonitis than was treatment without rifampicin (21.4 versus 42.8%; P = 0.004). In contrast, initial antibiotic regimen (cefazolin versus vancomycin) and concomitant exit-site infection did not have any effect on the risk for relapse or repeat peritonitis. S. aureus peritonitis is a serious complication of PD. Recent hospitalization is a major risk factor of methicillin resistance in the bacterial isolate. Rifampicin is a valuable adjunct in preventing relapse and repeat S. aureus peritonitis after the index episode.

Comprehensive malnutrition inflammation score as a marker of nutritional status in Chinese peritoneal dialysis patients.

BACKGROUND: Malnutrition is common among peritoneal dialysis (PD) patients. However, the ideal marker of nutritional status in PD patients remained controversial. METHODS: We studied 165 unselected adult PD patients. We compared the comprehensive Malnutrition-Inflammation Score (MIS) and the 7-point Subjective Global Assessment (SGA) score. RESULTS: The mean age was 59.2 +/- 11.5 years. Seventy patients were male. MIS significantly correlated with the SGA score (r =-0.667, P < 0.001). Of the 165 patients, 132 (80.0%) had similar classification of nutritional status by SGA and MIS (Group I); 17 (10.3%) were classified as normal by SGA but moderately malnourished by MIS (Group II), while 16 (9.7%) were classified as normal by MIS but moderately malnourished by SGA (Group III). Group II had been dialysed longer than Group I (71.7 +/- 50.3 vs 40.7 +/- 37.5 months, P = 0.011). As compared with Group I, Group III was more likely to require helper for PD exchange (37.5%vs 9.7%, P = 0.004), marginally more likely to be diabetic (62.5%vs 35.6%, P = 0.085) and had a slightly higher Charlson's comorbidity score (6.13 +/- 1.78 vs 4.98 +/- 2.1, P = 0.085), although the latter two were not statistically significant. CONCLUSION: MIS has a reasonable correlation with the conventional SGA score in PD patients. Patients with limited self-care capability, diabetes and multiple comorbidities probably had worse score (i.e. worse nutrition) revealed by SGA than by MIS, while patients who had been dialysed longer had worse score revealed by MIS than by SGA.

New-onset hyperglycemia in nondiabetic chinese patients started on peritoneal dialysis.

BACKGROUND: Glucose has been used as the osmotic agent added to standard peritoneal dialysis (PD) solutions since its inception. Patients who have no history of glucose intolerance may develop hyperglycemia after the initiation of PD therapy. However, the prevalence and long-term implications of new-onset hyperglycemia in PD patients has not been studied. METHODS: We studied 405 consecutive patients with renal failure newly started on PD therapy. Fasting plasma glucose levels 1 month after being stable on PD therapy were reviewed. Clinical factors affecting fasting plasma glucose levels were explored. Patients were followed up for 49.7 +/- 28.4 months. RESULTS: Of 405 patients, 136 had underlying diabetic nephropathy and another 17 had preexisting diabetes before starting PD therapy. Of the remaining 252 patients, fasting plasma glucose levels were greater than 200 mg/dL (>11.1 mmol/L) in 21 (8.3%) and 126 to 200 mg/dL (7.0 to 11.1 mmol/L) in 48 patients (19.0%). Seven patients required insulin therapy, 3 required low-dose sulfonylurea therapy, and all other patients had glucose levels controlled by means of dietary restriction only. Fasting plasma glucose levels significantly correlated with patient age (Pearson r = 0.278; P < 0.001), Charlson comorbidity score (r = 0.484; P < 0.001), baseline serum C-reactive protein level (r = 0.390; P < 0.001), and serum albumin level (r = -0.182; P < 0.001). However, patients with new-onset hyperglycemia had similar values for body weight, body mass index, peritoneal transport parameters, and ultrafiltration profile compared with other patients. At 36 months, actuarial survival rates were 93.7%, 85.3%, 81.6%, and 66.7% for patients with fasting glucose levels less than 100, 100 to less than 126, 126 to less than 200, and 200 mg/dL or greater (5.6, 5.6 to <7.0, 7.0 to <11.1, and >or=11.1 mmol/L) and 65.9% for patients with preexisting diabetes, respectively (overall log rank test, P < 0.001). CONCLUSION: New-onset hyperglycemia is common in patients without diabetes started on PD therapy. Contrary to common belief, obese patients do not appear to have a greater risk of hyperglycemia. Our results suggest that even mild hyperglycemia, with fasting plasma glucose level greater than 100 mg/dL (>5.6 mmol/L), is associated with worse survival in PD patients.

Increased subcutaneous insulin requirements in diabetic patients recently commenced on peritoneal dialysis.

BACKGROUND: Diabetic patients often have reduced insulin requirements when they progress to renal failure. Since peritoneal dialysis (PD) solution contains glucose, the insulin requirement of these patients often increases after commenced on PD. However, the change in insulin requirement has not been studied systematically. METHODS: We study 60 consecutive patients (32 male) with diabetic nephropathy newly started on PD. Their insulin requirement before and 6 months after initiation of dialysis is compared. Clinical factors affecting insulin requirement are explored. RESULTS: All patients received a standard 6 l/day dialysis exchange. The mean age was 60.3 +/- 8.9 years. Twelve patients did not require insulin before PD; four of them were started on insulin 6 months after dialysis. The average dosages of insulin 6 months before and after PD were 0.27 +/- 0.28 and 0.37 +/- 0.29 unit/kg/day, respectively (paired t-test, P < 0.001). The increment in dosage was 0.103 +/- 0.216 unit/kg/day. The dosage of insulin requirement correlates with the small solute transport of the peritoneal membrane, as represented by the mass transfer area coefficient (MTAC) of creatinine (r = -0.307, P = 0.017) and haemoglobin level (r = 0.284, P = 0.028), but not with body mass index (BMI). The change in insulin dosage correlates with the number of 2.5% dialysis cycle required per day (r = 0.433, P = 0.001), but not with peritoneal transport status or BMI. In patients who did not receive hypertonic exchange, the dosage of insulin increased by 1.5 +/- 11.1 unit/day. Each extra 2.5% 2 l exchange results in a 7.5 unit/day (95%CI 3.2-11.8, P = 0.001) increase in insulin requirement. CONCLUSION: Diabetic patients have a minimal increase in insulin requirement after initiation of PD per se, but the dosage of insulin increased markedly after exposure to hypertonic glucose solution. Our result provides a basis for the dosage adjustment of insulin in diabetic patients newly commenced on PD.

Prevalence and implications of isolated microscopic hematuria in asymptomatic Chinese pregnant women.

BACKGROUND: IgA nephropathy (IgAN) is the most common primary glomerulonephritis worldwide. However, the actual prevalence of microscopic hematuria and IgAN is unknown in the Chinese population. METHODS: We screened 7,828 consecutive pregnant women for microscopic hematuria in the antenatal clinic of a tertiary referral center. Persistent microscopic hematuria was defined as urine Hemastix (Bayer Diagnostics, Hong Kong) of 1+ for red cells in two clinic visits. Subjects were referred to the renal clinic for specialist evaluation, including measurement of blood pressure, serum creatinine, urine bacterial culture, and quantification of proteinuria. RESULT: There were 207 women (2.64%) with microscopic hematuria. Mean age was 31.8 +/- 5.0 years. In 101 patients (48.8%), there was proteinuria >0.1 g/day by quantitative assay. Hematuria was found to resolve before or shortly after delivery in 126 (60.9%) and 68 women (32.9%), respectively. Five patients (2.4%) had urinary tract infection proved by repeated urine culture, 1 had papillary necrosis, and 1 had duplex collecting system. Three patients were confirmed to have IgAN by renal biopsy; all had normal blood pressure and serum creatinine, but dysmorphic red cells in urine microscopy, and proteinuria of over 0.5 g/day that persisted after delivery. Renal biopsy on another woman showed no specific pathology. Two women were lost to follow-up, both with normal renal function and no detectable proteinuria. The overall prevalence of IgAN was 38 cases per 100,000 population (95% confidence interval: 8-112 cases). CONCLUSION: Microscopic hematuria is not uncommon in pregnant women, and IgAN is present in a small proportion of these patients. Further study is needed to determine whether screening for microscopic hematuria would allow early diagnosis and improve the prognosis of these patients.

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.

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.

The clinical course of peritoneal dialysis-related peritonitis caused by Corynebacterium species.

BACKGROUND: Corynebacterium species are part of the normal skin flora. The incidence of nosocomial infections caused by Corynebacterium species have increased substantially over the past two decades. However, the clinical course of Corynebacterium peritonitis complicating peritoneal dialysis remains unclear. METHOD: We reviewed all the Corynebacterium peritonitis in our dialysis unit from 1995 to 2002. During this period, there were 1485 episodes of peritonitis recorded; 27 (1.8%) of which were caused by Corynebacterium species. RESULTS: The underlying renal diagnosis and prevalence of comorbid conditions of the 27 patients were similar to our whole dialysis population. The bacteria isolated were resistant to penicillin in 8 cases (29.6%). Three cases (11.1%) had concomitant exit-site infection. The overall primary response rate was 74.1%; the complete cure rate was 37.0%. Episodes that received vancomycin as initial antibiotic had a marginally higher primary response rate (9 in 10 vs 11 in 17 episodes, P = 0.2) and complete cure rates (7 in 10 vs 3 in 17 episodes, P = 0.12) than the episodes that received cephalosporins, although neither of the differences was statistically significant. Thirteen cases (48.1%) had recurrent peritonitis after antibiotic therapy, 8 of which had the recurrent episode at least 30 days after stopping antibiotics (median 54 days, range 43-60 days). Eight recurrent cases (61.5%) were successfully cured by another 3 week course of intra-peritoneal vancomycin. CONCLUSIONS: Recurrent Corynebacterium peritonitis is common after a 2 week course of antibiotics. Recurrent Corynebacterium peritonitis may be delayed up to 2 months after the antibiotic is stopped. Recurrent peritonitis can usually be cured with a 3 week course of intra-peritoneal vancomycin, which is probably the preferred antibiotic regimen for Corynebacterium peritonitis.