30-year follow-up study of IgA nephritis in a Southeast Asian population: an evaluation of the Oxford histological classification
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BACKGROUND: In 1985 we reported that 11% of a cohort of 151 patients with IgA nephritis (IgAN) had developed end-stage renal disease (ESRD) after a follow-up period of 5 years. 15 years later, 35% had developed ESRD. METHODS: We retrieved 125 stored renal biopsy paraffin blocks of the original cohort. From these, 102 patients were included in the present study and scored according to the Oxford classification as 21 specimens with less than 8 glomeruli were excluded and in 2 others, tissue samples were too tiny for a re-block. ESRD was ascertained by linking the study cohort to the Singapore Renal Registry at the National Registry of Diseases Office. RESULTS: Renal survival curves for each of the Oxford MEST lesions: endocapillary proliferation (E) (p < 0.04), segmental glomerulosclerosis (S) (p < 0.05), tubular atrophy/interstitial fibrosis (p < 0.0001) were significantly associated with ESRD. Mesangial hypercellularity, less commonly associated with progressive chronic kidney disease (CKD) in the study, was independently associated with ESRD at 30 years (p < 0.03). In this cohort, E and S were associated with lower eGFR at presentation and doubling of serum creatinine in the first 5 years. This study's initial 5 years was representative of the "natural history" of IgAN since no renin-angiotensin system (RAS) blockers or immunosuppression were administered. This represents the early phase of disease progression. E and S may be considered "early disease activity predictors". CONCLUSION: Mesangial hypercellularity and tubular atrophy/interstitial fibrosis (M1 and T1/T2 lesion) of the Oxford classification independently predicted long term ESRD.
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The Course of Quality of Life in Patients on Peritoneal Dialysis: A 12-month Prospective Observational Cohort Study.

BACKGROUND: Quality of life (QOL) impairments are common in patients undergoing dialysis, and have been strongly associated with significant clinical outcomes like mortality and morbidity. Despite this, little is known about the course of QOL over time, especially for patients on peritoneal dialysis (PD). PURPOSE: This prospective study was set to explore course and determinants of QOL over 12 months in PD patients. METHODS: A total of 115 PD patients completed the SF-12 and Kidney Disease Quality of Life Short Form (KDQOL-SF) at baseline and 12 months later. Intra-individual changes in physical (physical component summary, PCS), mental (mental component summary, MCS), and Kidney Disease Component Summary scores (KDCS) were identified based on the minimally important clinical difference threshold. Clinical information was extracted from medical records. RESULTS: Of the patients, 74-80 % reported physical QOL impairments, as compared to 29-33 % who reported mental/emotional QOL impairments. PCS and MCS scores remained stable across 12 months. Significant deterioration was noted in the domains of patient satisfaction, staff encouragement, and social support, while there were significant increases in the perceived effects of kidney disease. Intra-individual trajectory analyses indicated that one in three patients reported deteriorating QOL. No sociodemographic or clinical variables were found to be associated with course of outcomes. CONCLUSIONS: Although PD offers the convenience of home-based care, it is associated with persisting QOL impairments and diminishing QOL over time, especially in domains related to quality of care and support. This highlights the need for improving or maintaining standards of care and support for PD patients as they become increasingly established on their regimes.

The effects of biocompatible compared with standard peritoneal dialysis solutions on peritonitis microbiology, treatment, and outcomes: the balANZ trial.

BACKGROUND: A multicenter, multi-country randomized controlled trial (the balANZ study) recently reported that peritonitis rates significantly improved with the use of neutral-pH peritoneal dialysis (PD) solutions low in glucose degradation products ("biocompatible") compared with standard solutions. The present paper reports a secondary outcome analysis of the balANZ trial with respect to peritonitis microbiology, treatment, and outcomes. METHODS: Adult incident PD patients with residual renal function were randomized to receive either biocompatible or conventional (control) PD solutions for 2 years. RESULTS: The safety population analysis for peritonitis included 91 patients in each group. The unadjusted geometric mean peritonitis rates in those groups were 0.30 [95% confidence interval (CI): 0.22 to 0.41] episodes per patient-year for the biocompatible group and 0.49 (95% CI: 0.39 to 0.62) episodes per patient-year for the control group [incidence rate ratio (IRR): 0.61; 95% CI: 0.41 to 0.90; p = 0.01]. When specific causative organisms were examined, the rates of culture-negative, gram-positive, gram-negative, and polymicrobial peritonitis episodes were not significantly different between the biocompatible and control groups, although the biocompatible group did experience a significantly lower rate of non-pseudomonal gram-negative peritonitis (IRR: 0.41; 95% CI: 0.18 to 0.92; p = 0.03). Initial empiric antibiotic regimens were comparable between the groups. Biocompatible fluid use did not significantly reduce the risk of peritonitis-associated hospitalization (adjusted odds ratio: 0.80; 95% CI: 0.48 to 1.34), but did result in a shorter median duration of peritonitis-associated hospitalization (6 days vs 11 days, p = 0.05). Peritonitis severity was more likely to be rated as mild in the biocompatible group (37% vs 10%, p = 0.001). Overall peritonitis-associated technique failures and peritonitis-related deaths were comparable in the two groups. CONCLUSIONS: Biocompatible PD fluid use was associated with a broad reduction in gram-positive, gram-negative, and culture-negative peritonitis that reached statistical significance for non-pseudomonal gram-negative organisms. Peritonitis hospitalization duration was shorter, and peritonitis severity was more commonly rated as mild in patients receiving biocompatible PD fluids, although other peritonitis outcomes were comparable between the groups.

The effect of low glucose degradation product, neutral pH versus standard peritoneal dialysis solutions on peritoneal membrane function: the balANZ trial.

BACKGROUND: The balANZ trial recently reported that neutral pH, low glucose degradation product (biocompatible) peritoneal dialysis (PD) solutions significantly delayed anuria and reduced peritonitis rates compared with conventional solutions. This article reports a secondary outcome analysis of the balANZ trial with respect to peritoneal membrane function. METHODS: Adult, incident PD patients with residual renal function were randomized to receive either biocompatible or conventional (control) PD solutions for 2 years. Peritoneal equilibration tests were performed at 1, 6, 12, 18 and 24 months. Peritoneal small solute clearances and ultra-filtration (UF) were measured at 3, 6, 9, 12, 18 and 24 months. RESULTS: Of the 185 patients recruited into the trial, 85 patients in the Balance group and 82 patients in the control group had peritoneal membrane function evaluated. Mean 4-h dialysate:plasma creatinine ratios (D:P Cr 4h) at 1 month were significantly higher in the Balance group compared with controls (0.67 ± 0.10 versus 0.62 ± 0.10, P = 0.002). Over the 2-year study period, mean D:P Cr 4 h measurements remained stable in the Balance group but increased significantly in controls [difference -0.004 per month, 95% confidence interval (95% CI) -0.005 to -0.002, P < 0.001]. Similar results were obtained for dialysate glucose ratios (D/D0 glucose). Peritoneal UF was significantly lower in the Balance group than in controls at 3 and 6 months. Over the 2-year study period, peritoneal UF increased significantly in the Balance group but remained stable in controls (difference 24 mL/day/month, 95% CI 9-39, P = 0.002). No differences in peritoneal small solute clearances, prescribed dialysate fill volumes or peritoneal glucose exposure were observed between the two groups. CONCLUSIONS: Biocompatible and conventional PD solutions exert differential effects on peritoneal small solute transport rate and UF over time. Adequately powered trials assessing the impact of these differential membrane effects on PD technique and patient survival rates are warranted.

Effects of biocompatible versus standard fluid on peritoneal dialysis outcomes.

The clinical benefits of using "biocompatible" neutral pH solutions containing low levels of glucose degradation products for peritoneal dialysis compared with standard solutions are uncertain. In this multicenter, open-label, parallel-group, randomized controlled trial, we randomly assigned 185 incident adult peritoneal dialysis patients with residual renal function to use either biocompatible or conventional solution for 2 years. The primary outcome measure was slope of renal function decline. Secondary outcome measures comprised time to anuria, fluid volume status, peritonitis-free survival, technique survival, patient survival, and adverse events. We did not detect a statistically significant difference in the rate of decline of renal function between the two groups as measured by the slopes of GFR: -0.22 and -0.28 ml/min per 1.73 m(2) per month (P=0.17) in the first year in the biocompatible and conventional groups, respectively, and, -0.09 and -0.10 ml/min per 1.73 m(2) per month (P=0.9) in the second year. The biocompatible group exhibited significantly longer times to anuria (P=0.009) and to the first peritonitis episode (P=0.01). This group also had fewer patients develop peritonitis (30% versus 49%) and had lower rates of peritonitis (0.30 versus 0.49 episodes per year, P=0.01). In conclusion, this trial does not support a role for biocompatible fluid in slowing the rate of GFR decline, but it does suggest that biocompatible fluid may delay the onset of anuria and reduce the incidence of peritonitis compared with conventional fluid in peritoneal dialysis.