Daily variation in death in patients treated by long-term dialysis: comparison of in-center hemodialysis to peritoneal and home hemodialysis.

BACKGROUND: There has been little study to date of daily variation in cardiac death in dialysis patients and whether such variation differs according to dialysis modality and session frequency. STUDY DESIGN: Observational cohort study using ANZDATA (Australia and New Zealand Dialysis and Transplant) Registry data. SETTING & PARTICIPANTS: All adult patients with end-stage kidney failure treated by dialysis in Australia and New Zealand who died between 1999 and 2008. PREDICTORS: Timing of death (day of week), dialysis modality, hemodialysis (HD) session frequency, and demographic, clinical, and facility variables. OUTCOMES & MEASUREMENTS: Cardiac and noncardiac mortality. RESULTS: 14,636 adult dialysis patients died during the study period (HD, n = 10,338; peritoneal dialysis [PD], n = 4,298). Cardiac death accounted for 40% of deaths and was significantly more likely to occur on Mondays in in-center HD patients receiving 3 or fewer dialysis sessions per week (n = 9,503; adjusted OR, 1.26; 95% CI, 1.14-1.40; P < 0.001 compared with the mean odds of cardiac death for all days of the week). This daily variation in cardiac death was not seen in PD patients, in-center HD patients receiving more than 3 sessions per week (n = 251), or home HD patients (n = 573). Subgroup analyses showed that deaths related to hyperkalemia and myocardial infarction also were associated with daily variation in risk in HD patients. This pattern was not seen for vascular, infective, malignant, dialysis therapy withdrawal, or other deaths. LIMITATIONS: Limited covariate adjustment. Residual confounding and coding bias could not be excluded. Possible type 2 statistical error due to limited sample size of home HD and enhanced-frequency HD cohorts. CONCLUSIONS: Daily variation in the pattern of cardiac deaths was observed in HD patients receiving 3 or fewer dialysis sessions per week, but not in PD, home HD, and HD patients receiving more than 3 sessions per week.

Recent peritonitis associates with mortality among patients treated with peritoneal dialysis.

Peritonitis is a major complication of peritoneal dialysis, but the relationship between peritonitis and mortality among these patients is not well understood. In this case-crossover study, we included the 1316 patients who received peritoneal dialysis in Australia and New Zealand from May 2004 through December 2009 and either died on peritoneal dialysis or within 30 days of transfer to hemodialysis. Each patient served as his or her own control. The mean age was 70 years, and the mean time receiving peritoneal dialysis was 3 years. In total, there were 1446 reported episodes of peritonitis with 27% of patients having ≥ 2 episodes. Compared with the rest of the year, there were significantly increased odds of peritonitis during the 120 days before death, although the magnitude of this association was much greater during the 30 days before death. Compared with a 30-day window 6 months before death, the odds for peritonitis was six-fold higher during the 30 days immediately before death (odds ratio, 6.2; 95% confidence interval, 4.4-8.7). In conclusion, peritonitis significantly associates with mortality in peritoneal dialysis patients. The increased odds extend up to 120 days after an episode of peritonitis but the magnitude is greater during the initial 30 days.

Repeated peritoneal dialysis-associated peritonitis: a multicenter registry study.

BACKGROUND: Determinants and outcomes of peritoneal dialysis (PD)-associated peritonitis occurring within 4 weeks of completion of therapy of a prior episode caused by the same (relapse) or different organism (recurrence) recently have been characterized. However, determinants and outcomes of peritonitis occurring more than 4 weeks after treatment of a prior episode caused by the same (repeated) or different organism (nonrepeated) are poorly understood. STUDY DESIGN: Observational cohort study using Australia and New Zealand Dialysis and Transplant Registry (ANZDATA) data. SETTING & PARTICIPANTS: All Australian PD patients between October 1, 2003, and December 31, 2007, with first episodes of repeated or nonrepeated peritonitis. PREDICTORS: Repeated versus nonrepeated peritonitis, according to International Society of PD (ISPD) criteria. OUTCOMES & MEASUREMENTS: Relapse, hospitalization, catheter removal, hemodialysis transfer, and death. RESULTS: After a peritonitis episode, the probability that a subsequent episode represented repeated rather than nonrepeated peritonitis was highest in the second month (41%), then progressively decreased to a stable level of 14% from 6 months onward. When first episodes of repeated (n = 245) or nonrepeated peritonitis (n = 824) were analyzed, repeated peritonitis was predicted independently by a shorter elapsed time from the prior episode (adjusted OR per day elapsed, 0.91; 95% CI, 0.88-0.94). Staphylococcus aureus and coagulase-negative staphylococcus were isolated more frequently in repeated peritonitis, whereas Gram-negative, streptococcal, and fungal organisms were recovered more frequently in nonrepeated peritonitis. Using multivariate logistic regression, repeated peritonitis was associated independently with higher relapse (OR, 5.41; 95% CI, 3.72-7.89) and lower hospitalization rates (OR, 0.63; 95% CI, 0.46-0.85), but catheter removal, hemodialysis transfer, and death rates similar to nonrepeated peritonitis. LIMITATIONS: Limited covariate adjustment. Residual confounding and coding bias could not be excluded. CONCLUSIONS: Repeated and nonrepeated peritonitis episodes are caused by different spectra of micro-organisms and have different outcomes. Study findings suggest that the ISPD definition for repeated peritonitis should be limited to 6 months.

Seasonal variation in peritoneal dialysis-associated peritonitis: a multi-centre registry study.

BACKGROUND: The role of seasonal variation in peritoneal dialysis (PD)-related peritonitis has been limited to a few small single-centre studies. METHODS: Using all 6610 Australian patients receiving PD between 1 October 2003 and 31 December 2008, we evaluated the influence of seasons on peritonitis rates (Poisson regression) and outcomes (multivariable logistic regression). RESULTS: The overall rate of peritonitis was 0.59 episodes per patient-year of treatment. Using winter as the reference season, the peritonitis incidence rate ratios (95% confidence interval) for summer, autumn and spring were 1.02 (0.95-1.09), 1.01 (0.94-1.08) and 0.99 (0.92-1.06), respectively. Significant seasonal variations were observed in the rates of peritonitis caused by coagulase-negative Staphylococci (spring and summer peaks), corynebacteria (winter peak) and Gram-negative organisms (summer and autumn peaks). There were trends to seasonal variations in fungal peritonitis (summer and autumn peaks) and pseudomonas peritonitis (summer peak). No significant seasonal variations were observed for other organisms. Peritonitis outcomes did not significantly vary according to season. CONCLUSIONS: Seasonal variation has no appreciable influence on overall PD peritonitis rates or clinical outcomes. Nevertheless, significant seasonal variations were observed in the rates of peritonitis due to specific microorganisms, which may allow institutions to more precisely target infection control strategies prior to higher risk seasons.

Use of aminoglycosides for peritoneal dialysis-associated peritonitis does not affect residual renal function.

BACKGROUND: Aminoglycosides offer several potential benefits in their treatment of peritoneal dialysis (PD)-associated peritonitis, including low cost, activity against Gram-negative organisms (including Pseudomonas aeruginosa), synergistic bactericidal activity against some Gram-positive organisms (such as Staphylococci) and relatively low propensity to promote antimicrobial resistance. However, there is limited conflicting evidence that aminoglycosides may accelerate loss of residual renal function (RRF) in PD patients. The aim of this study was to study the effect of aminoglycoside use on slope of decline in RRF. METHODS: The study included 2715 Australian patients receiving PD between October 2003 and December 2007 in whom at least two measurements of renal creatinine clearance were available. Patients were divided according to tertiles of slope of RRF decline (rapid, intermediate and slow). The primary outcome was the slope of RRF over time in patients who received aminoglycosides for PD peritonitis versus those who did not. RESULTS: A total of 1412 patients (52%) experienced at least one episode of PD peritonitis. An aminoglycoside was used as the initial empiric antibiotic in 1075 patients. The slopes of RRF decline were similar in patients treated and not treated with at least one course of aminoglycoside (median [interquartile range] -0.26 [-1.17 to 0.04] mL/min/1.73 m(2)/month versus -0.22 [-1.11 to 0.01] mL/min/1.73 m(2)/month, P = 0.9). The slopes of RRF decline were also similar in patients receiving repeated courses of aminoglycoside. CONCLUSIONS: Empiric treatment with aminoglycoside for peritonitis was not associated with an adverse effect on RRF in PD patients.

End-stage kidney disease due to haemolytic uraemic syndrome--outcomes in 241 consecutive ANZDATA registry cases.

BACKGROUND: The aim of this study was to investigate the characteristics and outcomes of patients receiving renal replacement therapy for end-stage kidney disease (ESKD) secondary to haemolytic uraemic syndrome (HUS). METHODS: The study included all patients with ESKD who commenced renal replacement therapy in Australia and New Zealand between 15/5/1963 and 31/12/2010, using data from the ANZDATA Registry. HUS ESKD patients were compared with matched controls with an alternative primary renal disease using propensity scores based on age, gender and treatment era. RESULTS: Of the 58422 patients included in the study, 241 (0.4%) had ESKD secondary to HUS. HUS ESKD was independently associated with younger age, female gender and European race. Compared with matched controls, HUS ESKD was not associated with mortality on renal replacement therapy (adjusted hazard ratio [HR] 1.14, 95% CI 0.87-1.50, p = 0.34) or dialysis (HR 1.34, 95% CI 0.93-1.93, p = 0.12), but did independently predict recovery of renal function (HR 54.01, 95% CI 1.45-11.1, p = 0.008). 130 (54%) HUS patients received 166 renal allografts. Overall renal allograft survival rates were significantly lower for patients with HUS ESKD at 1 year (73% vs 91%), 5 years (62% vs 85%) and 10 years (49% vs 73%). HUS ESKD was an independent predictor of renal allograft failure (HR 2.59, 95% CI 1.70-3.95, p < 0.001). Sixteen (12%) HUS patients experienced failure of 22 renal allografts due to recurrent HUS. HUS ESKD was not independently associated with the risk of death following renal transplantation (HR 0.92, 95% CI 0.35-2.44, p = 0.87). CONCLUSIONS: HUS is an uncommon cause of ESKD, which is associated with comparable patient survival on dialysis, an increased probability of renal function recovery, comparable patient survival post-renal transplant and a heightened risk of renal transplant graft failure compared with matched ESKD controls.

The effects of living distantly from peritoneal dialysis units on peritonitis risk, microbiology, treatment and outcomes: a multi-centre registry study.

BACKGROUND: The aim of the study was to determine whether distance between residence and peritoneal dialysis (PD) unit influenced peritonitis occurrence, microbiology, treatment and outcomes. METHODS: The study included all patients receiving PD between 1/10/2003 and 31/12/2008, using ANZDATA Registry data. RESULTS: 365 (6%) patients lived ≥100 km from their nearest PD unit (distant group), while 6183 (94%) lived <100 km (local group). Median time to first peritonitis in distant patients (1.34 years, 95% CI 1.07-1.61) was significantly shorter than in local patients (1.68 years, 95% CI 1.59-1.77, p = 0.001), whilst overall peritonitis rates were higher in distant patients (incidence rate ratio 1.32, 95% CI 1.20-1.46). Living ≥100 km away from a PD unit was independently associated with a higher risk of S. aureus peritonitis (adjusted odds ratio [OR] 1.64, 95% CI 1.09-2.47). Distant patients with first peritonitis episodes were less likely to be hospitalised (64% vs 73%, p = 0.008) and receive antifungal prophylaxis (4% vs 10%, p = 0.01), but more likely to receive vancomycin-based antibiotic regimens (52% vs 42%, p < 0.001). Using multivariable logistic regression analysis of peritonitis outcomes, distant patients were more likely to be cured with antibiotics alone (OR 1.55, 95% CI 1.03-2.24). All other outcomes were comparable between the two groups. CONCLUSIONS: Living ≥100 km away from a PD unit was associated with increased risk of S. aureus peritonitis, modified approaches to peritonitis treatment and peritonitis outcomes that were comparable to, or better than patients living closer to a PD unit. Staphylococcal decolonisation should receive particular consideration in remote living patients.

Relapsing and recurrent peritoneal dialysis-associated peritonitis: a multicenter registry study.

BACKGROUND: The causes, predictors, treatment, and outcomes of relapsed and recurrent peritoneal dialysis (PD)-associated peritonitis are poorly understood. STUDY DESIGN: Observational cohort study using Australia and New Zealand Dialysis and Transplant (ANZDATA) Registry data. SETTING & PARTICIPANTS: All Australian PD patients between October 1, 2003, and December 31, 2007, with first episodes of peritonitis. PREDICTORS: Demographic, clinical, and facility variables and type of peritonitis; relapse (same organism or culture-negative episode occurring within 4 weeks of completion of therapy of a prior episode or 5 weeks if vancomycin used); recurrence (different organism occurring within 4 weeks of completion of therapy of a prior episode or 5 weeks if vancomycin used); control (first peritonitis episode without relapse or recurrence). OUTCOMES & MEASUREMENTS: Hospitalization, catheter removal, hemodialysis therapy transfer, death. RESULTS: Of 6,024 PD patients studied, first episodes of relapsed, recurrent, and control peritonitis occurred in 356, 165, and 2,021 patients, respectively. Coagulase-negative staphylococci and Staphylococcus aureus accounted for 48% of relapsing peritonitis (adjusted OR, 1.26 [95% CI, 0.94-1.70] and 1.54 [95% CI, 1.08-2.19], respectively), but were much less likely to be isolated in recurrent peritonitis. Recurrent peritonitis was associated more frequently with fungi (13%; OR, 2.16; 95% CI, 1.12-4.17). The empirical antimicrobial approaches to relapsing and recurrent peritonitis were similar and their subsequent clinical outcomes were comparable. Compared with uncomplicated peritonitis, relapsed and recurrent peritonitis were associated with higher rates of catheter removal (22% vs 30% vs 37%, respectively; P < 0.001) and permanent hemodialysis therapy transfer (20% vs 25% vs 32%; P < 0.001), but similar rates of hospitalization (73% vs 70% vs 70%) and death (2.8% vs 2.0% vs 1.2%). LIMITATIONS: Limited covariate adjustment. Residual confounding and coding bias could not be excluded. CONCLUSIONS: Relapsed and recurrent peritonitis are caused by different spectra of micro-organisms, but are not readily clinically distinguishable at presentation. Empirical treatment with broad-spectrum antibiotics and subsequent adjustment according to antimicrobial susceptibilities results in similar clinical outcomes, albeit with appreciably higher rates of catheter removal and hemodialysis therapy transfer than for uncomplicated peritonitis.

End-stage kidney disease due to scleroderma--outcomes in 127 consecutive ANZDATA registry cases.

BACKGROUND: Scleroderma is an uncommon cause of end-stage kidney disease (ESKD) which carries significant morbidity and mortality risks. The aim of this study was to determine the prevalence, treatment and outcomes of scleroderma patients with ESKD. METHODS: A study was conducted of all ESKD patients enrolled in the ANZDATA registry, who commenced dialysis between 15 May 1963 and 31 December 2005, and remained on dialysis for at least 90 days. RESULTS: Of the 40 238 patients who commenced dialysis during the study period, 127 (0.3%) patients had ESKD secondary to scleroderma. Scleroderma ESKD patients were more likely than other ESKD patients to be female (72% versus 43%, P < 0.001), Caucasian (98% versus 79%, P < 0.001) and of lower BMI (22.7 ± 4.7 versus 26.0 ± 5.9, P < 0.001) with a higher prevalence of chronic lung disease (36 versus 14%, P < 0.001) and lower prevalence of diabetes mellitus (10% versus 32%, P < 0.001) and coronary artery disease (23% versus 35%, P = 0.01). Median survival was significantly shorter in scleroderma ESKD (2.43 years, 95% confidence interval (CI) 1.75-3.11 years) than other ESKD (6.02 years, 95% CI 5.89-6.14 years, log-rank score 55.7, P < 0.001). Renal recovery was more likely in scleroderma patients (10% versus 1%, P < 0.001) with a shorter time to recovery. Scleroderma was found to be an independent predictor for mortality (HR 2.47, 95% CI 1.99-3.05) and renal recovery (HR 11.1, 95% CI 6.37-19.4). Five year deceased donor and live donor renal allograft survival rates of recipients with scleroderma were 53 and 100%, respectively. CONCLUSIONS: Scleroderma is an uncommon cause of ESKD, which is associated with increased risks of both spontaneous renal recovery and mortality.

Peritoneal dialysis practice in Australia and New Zealand: a call to action.

Peritoneal dialysis technique survival in Australia and New Zealand is lower than in other parts of the world. More than two-thirds of technique failures are related to infective complications (predominantly peritonitis) and 'social reasons'. Practice patterns vary widely and more than one-third of peritoneal dialysis units do not meet the International Society of Peritoneal Dialysis minimum accepted peritonitis rate. In many cases, poor peritonitis outcomes reflect significant deviations from international guidelines. In this paper we propose a series of practical recommendations to improve outcomes in peritoneal dialysis patients through appropriate patient selection, prophylaxis and treatment of infectious complications, investigation of social causes of technique failure and a greater focus on patient education and clinical governance.

Predictors, treatment, and outcomes of non-Pseudomonas Gram-negative peritonitis.

Non-Pseudomonas Gram-negative (NPGN) peritonitis is a frequent, serious complication of peritoneal dialysis; however, previous reports have been limited to small, single-center studies. To gain insight on the frequency, predictors, treatment, and outcomes of NPGN peritonitis, we analyzed data in the ANZDATA registry of all adult Australian peritoneal dialysis patients over a 39-month period using multivariate logistic and multilevel Poisson regressions. There were 837 episodes of NPGN peritonitis (23.3% of all peritonitis) that occurred in 256 patients. The most common organism isolated was Escherichia coli, but included Klebsiella, Enterobacter, Serratia, Acinetobacter, Proteus, and Citrobacter, with multiple organisms identified in a quarter of the patients. The principal risk factor was older age, with poorer clinical outcome predicted by older age and polymicrobial peritonitis. The overall antibiotic cure rate was 59%. NPGN peritonitis was associated with significantly higher risks of hospitalization, catheter removal, permanent transfer to hemodialysis, and death compared to other organisms contributing to peritonitis. Underlying bowel perforation requiring surgery was uncommon. Hence, we show that NPGN peritonitis is a frequent, serious complication of peritoneal dialysis, which is frequently associated with significant risks, including death. Its cure with antibiotics alone is less likely when multiple organisms are involved.

Encapsulating peritoneal sclerosis: incidence, predictors, and outcomes.

Encapsulating peritoneal sclerosis is a complication of peritoneal dialysis characterized by persistent, intermittent, or recurrent adhesive bowel obstruction. Here we examined the incidence, predictors, and outcomes of encapsulating peritoneal sclerosis (peritoneal fibrosis) by multivariate logistic regression in incident peritoneal dialysis patients in Australia and New Zealand. Matched case-control analysis compared the survival of patients with controls equivalent for age, gender, diabetes, and time on peritoneal dialysis. Of 7618 patients measured over a 13-year period, encapsulating peritoneal sclerosis was diagnosed in 33, giving an incidence rate of 1.8/1000 patient-years. The respective cumulative incidences of peritoneal sclerosis at 3, 5, and 8 years were 0.3, 0.8, and 3.9%. This condition was independently predicted by younger age and the duration of peritoneal dialysis, but not the rate of peritonitis. Twenty-six patients were diagnosed while still on peritoneal dialysis. Median survival following diagnosis was 4 years and not statistically different from that of 132 matched controls. Of the 18 patients who died, only 7 were attributed directly to peritoneal sclerosis. Our study shows that encapsulating peritoneal sclerosis is a rare condition, predicted by younger age and the duration of peritoneal dialysis. The risk of death is relatively low and not appreciably different from that of competing risks for mortality in matched dialysis control patients.

Culture-negative peritonitis in peritoneal dialysis patients in Australia: predictors, treatment, and outcomes in 435 cases.

BACKGROUND: Reports of culture-negative peritoneal dialysis (PD)-associated peritonitis have been sparse, conflicting, and limited to small single-center studies. The aim of this investigation is to examine the frequency, predictors, treatment, and outcomes of culture-negative PD-associated peritonitis. STUDY DESIGN: Observational cohort study using Australia and New Zealand Dialysis and Transplant Registry (ANZDATA) data. SETTING & PARTICIPANTS: All Australian PD patients between October 1, 2003, and December 31, 2006. PREDICTORS: Demographic, clinical, and facility variables. OUTCOMES & MEASUREMENTS: Culture-negative PD-associated peritonitis occurrence, relapse, hospitalization, catheter removal, hemodialysis transfer, and death. RESULTS: Of 4,675 patients who received PD in Australia during the study period, 435 episodes of culture-negative peritonitis occurred in 361 individuals. Culture-negative peritonitis was not associated with demographic or clinical variables. A history of previous antibiotic treatment for peritonitis was more common with culture-negative than culture-positive peritonitis (42% vs 35%; P = 0.01). Compared with culture-positive peritonitis, culture-negative peritonitis was significantly more likely to be cured using antibiotics alone (77% vs 66%; P < 0.001) and less likely to be complicated by hospitalization (60% vs 71%; P < 0.001), catheter removal (12% vs 23%; P < 0.001), permanent hemodialysis therapy transfer (10% vs 19%; P < 0.001), or death (1% vs 2.5%; P = 0.04). Relapse rates were similar between the 2 groups. Patients with relapsed culture-negative peritonitis were more likely to have their catheters removed (29% vs 10% [P < 0.001]; OR, 3.83; 95% CI, 2.00-7.32). Administration of vancomycin or cephalosporin in the initial empiric antibiotic regimen and the timing of catheter removal were not significantly associated with clinical outcomes. LIMITATIONS: Limited covariate adjustment. Residual confounding and coding bias could not be excluded. CONCLUSIONS: Culture-negative peritonitis is a common complication with a relatively benign outcome. A history of previous antibiotic treatment is a significant risk factor for this condition.

Polymicrobial peritonitis in peritoneal dialysis patients in Australia: predictors, treatment, and outcomes.

BACKGROUND: The study aim was to examine the frequency, predictors, treatment, and clinical outcomes of peritoneal dialysis-associated polymicrobial peritonitis. STUDY DESIGN: Observational cohort study using ANZDATA (The Australia and New Zealand Dialysis and Transplant Registry) data. SETTING & PARTICIPANTS: All Australian peritoneal dialysis patients between October 2003 and December 2006. PREDICTORS: Age, sex, race, body mass index, baseline renal function, late referral, kidney disease, smoking status, comorbidity, peritoneal permeability, center, state, organisms, and antibiotic regimen. OUTCOMES & MEASUREMENTS: Polymicrobial peritonitis occurrence, relapse, hospitalization, catheter removal, hemodialysis transfer, and death. RESULTS: 359 episodes of polymicrobial peritonitis occurred in 324 individuals, representing 10% of all peritonitis episodes during 6,002 patient-years. The organisms isolated included mixed Gram-positive and Gram-negative organisms (41%), pure Gram-negative organisms (22%), pure Gram-positive organisms (25%), and mixed bacteria and fungi (13%). There were no significant independent predictors of polymicrobial peritonitis except for the presence of chronic lung disease. Compared with single-organism infections, polymicrobial peritonitis was associated with higher rates of hospitalization (83% vs 68%; P < 0.001), catheter removal (43% vs 19%; P < 0.001), permanent hemodialysis transfer (38% vs 15%; P < 0.001), and death (4% vs 2%; P = 0.03). Isolation of fungus or Gram-negative bacteria was the primary predictor of adverse clinical outcomes. Pure Gram-positive peritonitis had the best clinical outcomes. Patients who had their catheters removed >1 week after polymicrobial peritonitis onset were significantly more likely to be permanently transferred to hemodialysis therapy than those who had earlier catheter removal (92% vs 81%; P = 0.05). LIMITATIONS: Limited covariate adjustment. Residual confounding and coding bias could not be excluded. CONCLUSIONS: Polymicrobial peritonitis can be treated successfully using antibiotics alone without catheter removal in most cases, particularly when only Gram-positive organisms are isolated. Isolation of Gram-negative bacteria (with or without Gram-positive bacteria) or fungi carries a worse prognosis and generally should be treated with early catheter removal and appropriate antimicrobial therapy.

Coagulase-negative staphylococcal peritonitis in Australian peritoneal dialysis patients: predictors, treatment and outcomes in 936 cases.

BACKGROUND: Coagulase-negative staphylococcal (CNS) peritonitis is the most common cause of peritoneal dialysis (PD)-associated peritonitis. Previous reports of this important condition have been sparse and generally limited to single-centre studies. METHODS: The frequency, predictors, treatment and clinical outcomes of CNS peritonitis were examined by multivariate logistic regression and multilevel Poisson regression in all adult PD patients in Australia between 2003 and 2006. RESULTS: A total of 936 episodes of CNS peritonitis (constituting 26% of all peritonitis episodes) occurred in 620 individuals. The observed rate of CNS peritonitis was 0.16 episodes per patient-year. Lower rates of CNS peritonitis were independently predicted by Asian racial origin (adjusted odds ratio [OR], 0.52; 95% CI, 0.35-0.79), renovascular nephrosclerosis (OR, 0.40; 95% CI, 0.18-0.86), early referral to a renal unit prior to dialysis commencement (OR, 0.38; 95% CI, 0.19-0.79) and treatment with automated PD at any time during the PD career (OR, 0.79; 95% CI, 0.66-0.96). The majority of CNS peritonitis episodes were initially treated with intraperitoneal vancomycin or cephazolin in combination with gentamicin. This regimen was changed in 533 (57%) individuals after a median period of 3 days, most commonly to vancomycin monotherapy. The median total antibiotic course duration was 14 days. Compared with other forms of peritonitis, CNS episodes were significantly more likely to be cured by antibiotics alone (76 vs 64%, P < 0.001) and less likely to be complicated by hospitalization (61 vs 73%, P < 0.001), catheter removal (10 vs 26%, P < 0.001), temporary haemodialysis (2 vs 5%, P < 0.001), permanent haemodialysis transfer (9 vs 21%, P < 0.001) and death (1.0 vs 2.7%, P = 0.002). CNS peritonitis was also associated with a shorter duration of hospitalization, a longer time to catheter removal and a shorter duration of temporary haemodialysis. Catheter removal and permanent haemodialysis transfer were independently predicted by polymicrobial peritonitis and initial empiric administration of vancomycin (compared with cephalosporins). CNS peritonitis was associated with a higher relapse rate (17 vs 13%, P = 0.003) and relapsed CNS peritonitis was associated with a higher catheter removal rate (22 vs 7%, P < 0.001). Repeat peritonitis occurred in 194 (31%) individuals and the highest risk was in the second month after completion of antibiotic treatment for CNS peritonitis (OR, 1.87; 95% CI, 1.39-2.51 compared with >2 months). CONCLUSIONS: CNS peritonitis is a common complication with a relatively benign outcome compared with other forms of PD-associated peritonitis. Relapsed and repeat peritonitis are relatively common and are associated with worse outcomes.

Superior survival of high transporters treated with automated versus continuous ambulatory peritoneal dialysis.

BACKGROUND: Automated peritoneal dialysis (APD) is widely recommended for the management of high transporters by the International Society of Peritoneal Dialysis (ISPD), although there have been no adequate studies to date comparing the outcomes of APD and continuous ambulatory peritoneal dialysis (CAPD) in this high risk group. METHODS: The relative impact of APD versus CAPD on patient and technique survival rates was examined by both intention-to-treat (PD modality at Day 90) and 'as-treated' time-varying Cox proportional hazards model analyses in all patients who started PD in Australia or New Zealand between 1 April 1999 and 31 March 2004 and who had baseline peritoneal equilibration tests confirming the presence of high peritoneal transport status. RESULTS: During the study period, 4128 patients commenced PD. Of these, 628 patients were high transporters on PD at Day 90 (486 on APD and 142 on CAPD). Compared to high transporters treated with CAPD, APD-treated high transporters were more likely to be younger and Caucasian, and less likely to be diabetic. On multivariate intention-to-treat analysis, APD treatment was associated with superior survival [adjusted hazard ratio (HR) 0.56, 95% confidence interval (CI) 0.35-0.87] and comparable death-censored technique survival (HR 0.88, 95% CI 0.64-1.21). Superior survival of high transporters treated with APD versus CAPD was also confirmed in supplemental as-treated analysis (HR 0.72, 95% CI 0.54-0.96), matched case-control analysis (HR 0.60, 95% CI 0.36-0.96) and subgroup analysis of high transporters treated entirely with APD versus those treated entirely with CAPD (HR 0.29, 95% CI 0.14-0.60). There were no statistically significant differences in patient survival or death-censored technique survival between APD and CAPD for any other transport group, except for low transporters, who experienced a higher mortality rate on APD compared with CAPD (HR 2.19, 95% CI 1.02-4.70). CONCLUSIONS: APD treatment is associated with a significant survival advantage in high transporters compared with CAPD. However, APD treatment is associated with inferior survival in low transporters.

Enterococcal peritonitis in Australian peritoneal dialysis patients: predictors, treatment and outcomes in 116 cases.

UNLABELLED: Background. Enterococcal peritonitis is a serious complication of peritoneal dialysis (PD), although reports of this condition in the literature are exceedingly limited. Methods. The frequency, predictors, treatment and clinical outcomes of enterococcal peritonitis were investigated in all 4675 patients receiving PD in Australia between 1 October 2003 and 31 December 2006. Results. One hundred and sixteen episodes of enterococcal peritonitis occurred in 103 individuals. Enterococcal peritonitis tended to be associated with older age, Maori and Pacific Islander racial origin, renovascular disease and coronary artery disease. Polymicrobial peritonitis, defined as recovery of two or more organisms from dialysate effluent, was significantly more common when an Enterococcus species was isolated than when it was not (45% vs 5%, respectively, P < 0.001, odds ratio 13.4, 95% CI 9.45-19.0). Although international guidelines recommend intraperitoneal ampicillin therapy, only 8% of patients with pure enterococcal peritonitis were treated with this agent, whilst the majority (78%) received vancomycin monotherapy. Overall, 59 (51%) patients with enterococcal peritonitis were successfully treated with antibiotics without experiencing relapse, catheter removal or death. The sole independent predictor of adverse clinical outcomes was recovery of additional (non-Enterococcus) organisms. Polymicrobial enterococcal peritonitis was associated with very high rates of hospitalization (83%), catheter removal (52%), permanent haemodialysis transfer (50%) and death (5.8%). In contrast, clinical outcomes were broadly comparable for pure enterococcal and non-enterococcal peritonitis (hospitalization 75% vs 69%, respectively; catheter removal 25% vs 21%; permanent haemodialysis transfer 17% vs 17%; death 1.6% vs 2.2%) although worse than non-enterococcal Gram-positive peritonitis (63%, 12%, 3% and 0.6%, respectively). Removal of the PD catheter within 1 week of enterococcal peritonitis onset was associated with a lower probability of permanent haemodialysis transfer than later removal (74% vs 100%, P = 0.03). CONCLUSIONS: Enterococcal peritonitis is associated with an increased risk of catheter removal, permanent haemodialysis transfer and death, particularly when other organisms are isolated in the same episode.

Predictors and outcomes of fungal peritonitis in peritoneal dialysis patients.

Fungal peritonitis is a serious complication of peritoneal dialysis but previous reports on this have been limited to small, single-center studies. Using all Australian peritoneal dialysis patients, we measured predictors, treatments, and outcomes of this condition by logistic regression and multilevel, multivariate Poisson regression. This encompassed 66 centers over a 4-year period that included 162 episodes of fungal peritonitis (4.5% of all peritonitis episodes) that occurred in 158 individuals. Candida albicans (25%) and other Candida species (44%) were the most common fungi isolated. Fungal peritonitis was independently predicted by indigenous race and prior treatment of bacterial peritonitis. Peritonitis episodes occurring after 7 and 60 days of treatment for previous bacterial peritonitis decreases in the probability of fungal peritonitis 23 and 6%, respectively. Compared with other organisms, fungal peritonitis was associated with significantly higher rates of hospitalization, catheter removal, transfer to permanent hemodialysis, and death. The risks of repeat fungal peritonitis and death were lowest with catheter removal combined with antifungal therapy when compared to either intervention alone. Our study shows that fungal peritonitis is a serious complication of peritoneal dialysis and should be strongly suspected in the context of recent antibiotic treatment for bacterial peritonitis.

Associations of dialysis modality and infectious mortality in incident dialysis patients in Australia and New Zealand.

BACKGROUND: The aim of the present investigation is to compare rates, types, causes, and timing of infectious death in incident peritoneal dialysis (PD) and hemodialysis (HD) patients in Australia and New Zealand. STUDY DESIGN: Observational cohort study using the Australian and New Zealand Dialysis and Transplant Registry data. SETTING & PARTICIPANTS: The study included all patients starting dialysis therapy between April 1, 1995, and December 31, 2005. PREDICTOR: Dialysis modality. OUTCOMES & MEASUREMENTS: Rates of and time to infectious death were compared by using Poisson regression, Kaplan-Meier, and competing risks multivariate Cox proportional hazards model analyses. RESULTS: 21,935 patients started dialysis therapy (first treatment PD, n = 6,020; HD, n = 15,915) during the study period, and 1,163 patients (5.1%) died of infectious causes (PD, 529 patients; 7.6% versus HD, 634 patients; 4.2%). Incidence rates of infectious mortality in PD and HD patients were 2.8 and 1.7/100 patient-years, respectively (incidence rate ratio PD versus HD, 1.66; 95% confidence interval [CI], 1.47 to 1.86). After performing competing risks multivariate Cox analyses allowing for an interaction between time on study and modality because of identified nonproportionality of hazards, PD consistently was associated with increased hazard of death from infection compared with HD after 6 months of treatment (<6 months hazard ratio [HR], 1.08; 95% CI, 0.76 to 1.54; 6 months to 2 years HR, 1.31; 95% CI, 1.09 to 1.59; 2 to 6 years HR, 1.51; 95% CI, 1.26 to 1.80; >6 years HR, 2.76; 95% CI, 1.76 to 4.33). This increased risk of infectious death in PD patients was largely accounted for by an increased risk of death caused by bacterial or fungal peritonitis. LIMITATIONS: Patients were not randomly assigned to their initial dialysis modality. Residual confounding and coding bias could not be excluded. CONCLUSIONS: Dialysis modality selection significantly influences risks, types, causes, and timing of fatal infections experienced by patients with end-stage kidney disease in Australia and New Zealand.

Corynebacterium peritonitis in Australian peritoneal dialysis patients: predictors, treatment and outcomes in 82 cases.

BACKGROUND: Infection due to Corynebacterium species has been reported with increasing frequency over recent decades. The impacts of enhanced laboratory detection together with widespread use of new peritoneal dialysis (PD) connection technology and antimicrobial prophylaxis strategies on Corynebacterium PD-associated peritonitis have not been well studied. METHODS: We investigated the frequency, predictors, treatment and clinical outcomes of Corynebacterium peritonitis in all Australian adult patients involving 66 centres who were receiving PD between 1 October 2003 and 31 December 2006. RESULTS: Eighty-two episodes of Corynebacterium peritonitis (2.3% of all peritonitis episodes) occurred in 65 (1.4%) PD patients. Ten (15%) patients experienced more than one episode of Corynebacterium peritonitis and additional organisms were isolated in 12 (15%) episodes of Corynebacterium peritonitis. The incidence of Corynebacterium peritonitis was significantly and independently predicted only by BMI: RR 2.72 (95% CI 1.38-5.36) for the highest tertile BMI compared with the lowest tertile. The overall cure rate with antibiotics alone was 67%, which was similar to that of peritonitis due to other organisms. Vancomycin was the most common antimicrobial agent administered in the initial empiric and subsequent antibiotic regimens, although outcomes were similar regardless of antimicrobial schedule. Corynebacterium peritonitis not infrequently resulted in relapse (18%), repeat peritonitis (15%), hospitalization (70%), catheter removal (21%), permanent haemodialysis transfer (15%) and death (2%). The individuals who had their catheters removed more than 1 week after the onset of Corynebacterium peritonitis had a significantly higher risk of permanent haemodialysis transfer than those who had their catheters removed within 1 week (90% versus 43%, P < 0.05). CONCLUSIONS: Corynebacterium is an uncommon but significant cause of PD-associated peritonitis. Complete cure with antibiotics alone is possible in the majority of patients, and rates of adverse outcomes are comparable to those seen with peritonitis due to other organisms. Use of vancomycin rather than cephazolin as empiric therapy does not impact outcomes, and a 2-week course of antibiotic therapy appears sufficient. If catheter removal is required, outcomes are improved by removing the catheter within 1 week of peritonitis onset.