ISPD peritonitis guideline recommendations: 2022 update on prevention and treatment

Peritoneal dialysis (PD)-associated peritonitis is a serious complication of PD and prevention and treatment of such is important in reducing patient morbidity and mortality. The ISPD 2022 updated recommendations have revised and clarified definitions for refractory peritonitis, relapsing peritonitis, peritonitis-associated catheter removal, PD-associated haemodialysis transfer, peritonitis-associated death and peritonitis-associated hospitalisation. New peritonitis categories and outcomes including pre-PD peritonitis, enteric peritonitis, catheter-related peritonitis and medical cure are defined. The new targets recommended for overall peritonitis rate should be no more than 0.40 episodes per year at risk and the percentage of patients free of peritonitis per unit time should be targeted at >80% per year. Revised recommendations regarding management of contamination of PD systems, antibiotic prophylaxis for invasive procedures and PD training and reassessment are included. New recommendations regarding management of modifiable peritonitis risk factors like domestic pets, hypokalaemia and histamine-2 receptor antagonists are highlighted. Updated recommendations regarding empirical antibiotic selection and dosage of antibiotics and also treatment of peritonitis due to specific microorganisms are made with new recommendation regarding adjunctive oral N-acetylcysteine therapy for mitigating aminoglycoside ototoxicity. Areas for future research in prevention and treatment of PD-related peritonitis are suggested.

Exploration of the correlation between intestinal flora and Escherichia coli peritoneal dialysis-related peritonitis

BACKGROUND

Escherichia coli peritonitis (EP) is a serious complication of peritoneal dialysis (PD). Gut microbiota alterations occur in end-stage renal disease (ESRD) patients. The relationship between the gut microbiota and PD-related peritonitis is still poorly understood. It is unclear whether the intestinal flora is involved in the pathogenesis of EP.

METHODS

We collected fecal samples from EP patients and normal group (NG) PD patients. 16S rRNA sequencing was used to analyze the gut microbiota of EP and NG patients. The demographic data and clinical indicators of all patients were collected.

RESULTS

Six EP patients and 28 NG patients were recruited for this study. The analysis of fecal community diversity with 16S rDNA sequencing showed an obvious change in the microbial structure of EP patients, where Bacteroidetes and Synergistetes were upregulated at different levels, while Bacilli and Lactobacillus were downregulated at different levels compared to the NG group. Additionally, decreased gene function associated with metabolic pathways was observed in EP patients.

CONCLUSIONS

The altered composition of the gut microbiota in EP patients provided deeper insights into the pathogenesis of EP, and these biomarkers might be established as potential therapeutic targets that deserve further exploration.

Phenotypic and Molecular Characterization of Nonfermenting Gram-Negative Bacilli Causing Peritonitis in Peritoneal Dialysis Patients

(1) Background: Peritonitis due to nonfermenting Gram-negative bacilli (NF-GNB) is a dramatic complication of peritoneal dialysis (PD) with bad outcomes. Previous studies of PD-related peritonitis due to Pseudomonas species have shown a low-resolution rate, without a high resistance rate to antipseudomonal antibiotics. This suggests that bacterial virulence factors can act and influence peritonitis evolution. This study aimed to describe the microbiological characteristics of NF-GNB causing PD-related peritonitis and analyze their influence on the outcome. (2) Methods: We analyze the 48 isolates from NF-GNB peritonitis, which were stored in our culture collection regarding bacterial resistance, biofilm, and other virulence factors’ production, and clonal profile. Additionally, we collected data on treatment and outcomes from patients’ clinical registers. (3) Results: The etiologies were species of Pseudomonas (50%), Acinetobacter (36%), and other NF-GNB (14%). There was a high (75%) proportion of biofilm producer lineages. The in vitro susceptibility rate of Pseudomonas spp. to amikacin, ciprofloxacin, and ceftazidime was significantly greater than that of Acinetobacter spp. and other species; however, there was a similar low-resolution rate (<45%) among the episodes attributable to them. Pseudomonas species have a polyclonal profile, while we found a clone of five multiresistant Acinetobacter baumannii over an 8-year interval (2000–2008), which suggest an origin from the healthcare environment. (4) Conclusions: We are not able to identify any predictor of outcome, but it is possible that biofilm and others virulence factors can act in concert and contribute to the bad outcome.

The impact of intraperitoneal antibiotic administration in patients with peritoneal dialysis-related peritonitis: systematic review and meta-analysis

Background

Peritonitis is a common and clinically important complication in patients receiving peritoneal dialysis (PD). Antibiotic administration is essential for PD-related peritonitis, but routes of administration have not been established enough. Here, we performed a systematic review to assess the efficacy and safety of intraperitoneal (IP) antibiotic administration compared to intravenous (IV) antibiotic administration in patients with PD-related peritonitis.

Methods

Cochrane CENTRAL, MEDLINE, and Ichushi-Web were searched in June 2017. Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines were followed, and articles were screened by four independent reviewers.

Results

Two randomized controlled trials (113 patients) were identified. IP antibiotic administration was more effective than IV antibiotic administration. The pooled risk difference between IP and IV was 0.13 (95% CI − 0.17 to 0.43). Safety assessment indicated less frequency of side effects in patients receiving IP antibiotic administration. The pooled risk ratios of IV to IP regarding adverse drug reaction-related and administration route-related side effects were 5.13 (0.63 to 41.59) and 3.00 (0.14 to 65.90), respectively.

Conclusion

The systematic review and meta-analysis suggested that IP antibiotic administration is more effective and safer in patients with PD-related peritonitis compared to IV antibiotic administration.

Risk Factors Influencing the Decline of Residual Renal Function in Continuous Ambulatory Peritoneal Dialysis Patients

Objective

To assess the nature of the decline in residual renal function (RRF) after the initiation of peritoneal dialysis, and to identify risk factors influencing the preservation of RRF.

Design

A retrospective single-center study.

Setting

Tertiary medical center.

Patients

Eighty patients who were clinically stable and had been on continuous ambulatory peritoneal dialysis (CAPD) for a minimum of 6 months.

Main Outcome Measures

All subjects had at least three measurements of RRF, which was calculated as the average of creatinine clearance (Ccr) and urea clearance from a 24-hour urine collection. All measurements of RRF were plotted on a logarithmic scale and a linear scale against the duration of CAPD. Covariables used in the correlation analyses were age, sex, the presence of diabetes mellitus, mean blood pressure, mean diastolic blood pressure, hematocrit and Ccr at the start of peritoneal dialysis, peritoneal membrane transport characteristics by peritoneal equilibration test (PET), and the rate of peritonitis.

Results

A significant correlation was found between CAPD duration and RRF decline represented on a logarithmic scale with a correlation coefficient ( r) of 0.355 ( p < 0.001). In contrast, on a linear scale, the correlation coefficient was only 0.273 ( p < 0.01). By linear multiple regression analysis, the only independent risk factor for the decline of RRF was the rate of peritonitis ( r = -0.446, p < 0.001).

Conclusion

These results suggest that RRF declines exponentially rather than linearly with time, and that the rate of peritonitis is an independent risk factor for the decline of RRF in CAPD patients.

Fibrin Glue is Useful in Preventing Early Dialysate Leakage in Children on Chronic Peritoneal Dialysis

Objective

To assess if application of fibrin glue sealant to the peritoneal cuff suture is useful in the prevention of early dialysate leakage in children with end-stage renal disease on chronic peritoneal dialysis (CPD).

Design

Single-center, open-label, prospective randomized study.

Setting

University Pediatric Hospital.

Methods

52 catheters were implanted in 45 children (mean age 6.2 ± 4.5 years). Catheters were randomly assigned to either the control group or the sealant group. In the latter group, 1 mL of fibrin glue sealant was applied to the peritoneal cuff suture. 18 catheters were used for the first time within 5 days after implantation (early-used catheters). Leakage, exit-site or tunnel infection, peritonitis, and adverse secondary effects were evaluated during the initial 60 days after implantation.

Results

No adverse secondary effects were seen after the application of the fibrin glue sealant. The incidence of exit/tunnel infection and peritonitis was similar in the two groups. The incidence of leakage was significantly lower in the sealant group ( p < 0.02). In the early-used catheters, leakage was detected in 9% of the catheters in the sealant group and in 57% of the control group ( p < 0.05).

Conclusions

The application of 1 mL of fibrin glue to the peritoneal cuff suture prevented early dialysate leakage without secondary adverse effects in children on CPD.

Intraperitoneal Ciprofloxacin and Rifampicin versus Cephradine as Initial Treatment of (C)Apd-Related Peritonitis: A Prospective Randomized Multicenter Comparison (Cipper Trial)

Objective

The initial treatment of peritonitis has evolved from single-agent to combination regimens. The initial response rates improved with these newer regimens but relapsing peritonitis continues to occur. For biofilm-embedded or intracellularly sequestrated bacteria, a combination of intracellularly- and biofilm-active agents such as ciprofloxacin and rifampicin might be beneficial. Many Dutch centers continue to use cephradine as initial treatment, claiming clinically adequate responses with this regimen. We compared the impact of these two regimens on outcome in patients who developed a new episode of peritonitis.

Design

Prospective randomized open trial.

Setting

Multicenter study including 14 Dutch dialysis units.

Patients and Interventions

From October 1996 to October 1999, 367 patients from 14 centers were randomized to be treated with ciprofloxacin + rifampicin (CR; each 50 mg/L) or cephradine (C; 250 mg/L) in case of peritonitis. Of these 367 patients, 98 developed peritonitis, 44 of whom were treated with CR and 54 with C.

Main Outcome Measures

Clinical response, divided into early (during the 2 weeks of therapy) and late (including the following 4 weeks) response. Success was defined as disappearance of all signs and symptoms by days 4 - 6, through day 42. Bacteriological response was either success (eradication) or failure (persistence, superinfection, or eradication with relapse/reinfection).

Results

The groups were comparable for age, sex, duration of continuous ambulatory/automated peritoneal dialysis, and occurrence of diabetes. Bacteriological cultures in both groups revealed predominantly gram-positive micro-organisms. Initial and late clinical successes were obtained in 27/54 and 20/54 episodes (50% and 37%) in the C group, and 33/44 and 28/44 episodes (75% and 63.6%) in the CR group ( p = 0.021 and p = 0.019). Bacteriological success occurred in 29.6% in the C group, and in 59.1% in the CR group ( p = 0.026), with failure in 46.3% and 18.2%, respectively. Peritonitis episodes were bacteriologically not evaluable in 24.1% of episodes in the C group and 22.7% of episodes in the CR group, due mostly to no growth in the initial culture.

Conclusion

The CIPPER Trial showed ciprofloxacin + rifampicin to be superior to cephradine as empiric treatment of peritonitis.

Influence of Climate on the Incidence of Peritoneal Dialysis-Related Peritonitis

Objective

The use of peritoneal dialysis has expanded in many developing subtropical countries; however, the role of climatic factors in dialysis-related peritonitis has not been studied in detail.

Design

Retrospective study.

Setting

A single regional dialysis unit in a university teaching hospital.

Patients

We reviewed all cases of dialysis-related peritonitis treated in our dialysis unit from January 1995 to December 2001. Information was collected on demographic data, microbiologic etiology, associated catheter exit-site infection, and clinical response.

Results

In 24 059 patient-months of follow-up, 1344 episodes of peritonitis were recorded. There were significantly more peritonitis episodes in July and August [odds ratio 1.17, 95% confidence interval (CI) 1.03 – 1.32], and fewer peritonitis episodes in December (odds ratio 0.79, 95% CI 0.61 – 0.98). There was also a trend of more peritonitis in March (odds ratio 1.18, 95% CI 0.97 – 1.41), but the difference was not statistically significant. When the incidence of peritonitis caused by individual bacterial species was further analyzed, we found a significant seasonal variation in the rate of peritonitis caused by gram-negative bacteria, except Pseudomonas (overall chi-square test, p = 0.002). A similar trend of seasonal variation was also observed in gram-positive peritonitis, but the result was not statistically significant. There was significant seasonal variation in the rate of peritonitis that had coexisting exit-site infection (overall chi-square test, p = 0.02), with peak incidence in July. However, the proportion of peritonitis that had coexisting exit-site infection did not have significant seasonal variation. There was significant correlation between monthly peritonitis rate and average humidity ( r = –0.346, p < 0.002) and temperature ( r = –0.264, p = 0.015).

Conclusions

There is substantial seasonal variation in the incidence of dialysis-related peritonitis, with peak incidence in the months that are hot and humid. Keeping a cool and dry living environment may help to reduce peritonitis in peritoneal dialysis patients in tropical countries.

Longitudinal Study of Peritoneal Membrane Function in Continuous Ambulatory Peritoneal Dialysis: Relationship with Peritonitis and Fibrosing Factors

Background

The peritoneal equilibration test (PET) is a useful assessment of peritoneal function in continuous ambulatory peritoneal dialysis (CAPD) patients. However, the natural course of longitudinal change in peritoneal transport is not well defined.

Patients

We studied 105 unselected CAPD patients. Average age at enrollment was 50.7 ± 11.3 years.

Methods

A PET was performed at enrollment. Peritoneal transport was expressed as dialysate-to-plasma creatinine ratio at 4 hours (D/P). Fibrosing factors and mesothelial cell markers, including TGFJJ, epidermal growth factor (EGF), platelet-derived growth factor (PDGF), hyaluronan, and cancer antigen 125 (CA125), were measured in overnight peritoneal dialysate effluent (PDE). Patients were followed for two years. Peritonitis episodes were recorded. Severe peritonitis was defined as an episode that required catheter removal or antibiotic therapy for more than 3 weeks. After two years, 75 patients were still alive and on CAPD.

Results

The PET was repeated in 64 patients, of whom 35 were male and 9 had diabetes. The change in D/P over two years was represented as ΔD/P. No significant change in peritoneal transport was seen after two years (D/P: 0.56 ± 0.12 vs 0.55 ± 0.13). A centripetal pattern of change in D/P was observed. The ΔD/P had normal distribution and was inversely correlated with D/P at baseline ( r = -0.427, p < 0.005). Both results suggest a regression-to-mean phenomenon. The ΔD/P had no significant correlation with the total number of peritonitis episodes (Spearman r = 0.052, p = 0.74), but after severe peritonitis, affected patients had higher ΔD/P than patients who experienced no severe infection (0.040 ± 0.136 vs -0.032 ± 0.120, p < 0.05). For patients with no episodes of severe peritonitis (n = 47), ΔD/P was weakly correlated with baseline TGFβ level ( r = -0.506, p < 0.01). No correlation was seen between the levels of other fibrosing factors and change in peritoneal transport.

Conclusions

Our findings suggest that the centripetal change of peritoneal transport probably reflects a regression-to-mean phenomenon. Peritoneal transport increases after severe peritonitis. The role of TGFβ levels in PDE with regard to longitudinal change in peritoneal transport requires further study.

Intravenous Vancomycin Pharmacokinetics in Automated Peritoneal Dialysis Patients

The pharmacokinetics of intravenous (IV) vancomycin was studied in automated peritoneal dialysis (APD) patients who received a single IV dose of vancomycin (15 mg/kg total body weight). Dialysate samples were collected at the beginning, middle, and end of dwells 1 – 3 (on-cycler), and at the end of dwells 4 and 5 (off-cycler), for a 24-hour period. Blood samples were collected at the beginning, middle, and end of dwells 1 – 3 (on-cycler), and at the end of dwell 5 (off-cycler) for a 24-hr period. Pharmacokinetics parameters were calculated assuming a one-compartment model. Glomerular filtration rate (GFR) and vancomycin clearance (Cl) values were normalized to 1.73 m2. Ten patients [4 males, 6 females; 47.4 ± 9.9 years of age (mean ± SD)] who had received PD for a median 3.5 months (range 2 – 66 months) were studied. Dwell times were 2.3 ± 0.1 hours on cycler and 7.3 ± 0.1 hours off cycler. Vancomycin half-life was significantly different on-cycler than off-cycler (11.6 ± 5.2 hr vs 62.8 ± 33.0 hr; p < 0.001). Vancomycin total Cl (ClT) was 7.4 ± 2.0 mL/min. Renal Cl (ClR) and PD Cl (ClPD) accounted for 23.6% and 28.0% of ClT, respectively. ClR correlated with GFR (ClR = 0.90 GFR – 1.01; r2 = 0.79; p = 0.008). Mean vancomycin serum and dialysate end-of-dwell concentrations were above minimum inhibitory concentration of susceptible organisms (5 mg/mL) for the first cycler and the second ambulatory exchanges only.

The results of this study suggest that, to provide adequate concentrations for susceptible organisms over a 24-hour period, current intermittent vancomycin dosing recommendations for PD-related peritonitis need to be changed to 35 mg/kg intraperitoneally on day 1, then 15 mg/kg IP thereafter ( i.e., once daily) in APD patients.

Challenging the Current Treatment Paradigm for Methicillin-Resistant Staphylococcus Epidermidis Peritonitis in Peritoneal Dialysis Patients

Objectives

To analyze clinical outcomes of Staphylococcus epidermidis peritoneal dialysis peritonitis before and after an interventional switch from a vancomycin/tobramycin to a cefazolin/tobramycin regimen for empiric treatment. To examine risk factors associated with clinical failure.

Design

A retrospective study.

Setting

A peritoneal dialysis program within a university-affiliated tertiary-care hospital.

Patients

93 episodes of S. epidermidis peritonitis over a 6-year period.

Interventions

Clinical responses were compared between treatments using chi-square or Fisher's exact test. Univariate and multivariate analyses were used to identify significant risk factors for clinical failure.

Measurements and Main Results

There was no difference in the overall response rates observed with vancomycin (40/49; 81.6%) and cefazolin (23/29; 79.3%) regimens for episodes of S. epidermidis peritonitis. Furthermore, the presence of methicillin resistance in 63 of 93 cases (67.7%) had no influence on clinical outcome, with response rates of 83.9% (26/31) and 82.4% (14/17) for empiric vancomycin and cefazolin regimens, respectively. Tobramycin therapy of less than 2 days was an independent risk factor for clinical failure in multivariate logistic regression analysis (odds ratio 4.44, 95% confidence interval 1.28 – 15.48; p = 0.02).

Conclusions

Empiric treatment with intraperitoneal cefazolin was as effective as vancomycin for S. epidermidis peritonitis despite a high prevalence of methicillin resistance. Tobramycin therapy of less than 2 days was strongly associated with treatment failure.

Peritonitis Due to Stenotrophomonas Maltophilia in Patients Undergoing Chronic Peritoneal Dialysis

The occurrence of cases of Stenotrophomonas maltophilia peritonitis in chronic peritoneal dialysis (PD) patients prompted a review of our experience with this condition. A search of microbiology records revealed seven episodes of S. maltophilia peritonitis in 7 patients in 1996 — 3.8% of all PD patients — compared to no cases in 1994 and 1995 ( p = 0.01). Patients ranged in age from 16 to 64 years; there were 3 males and 4 females. Six of seven episodes of peritonitis were community acquired and one was hospital acquired. No temporal clustering of cases was seen. Patients were from different urban and rural communities. Patients used the same commercially supplied dialysate fluid, different dialysis techniques, and were taught a no-touch technique for connection. Treatment of peritonitis required removal of the Tenckhoff catheter in 4 of 7 cases. Fingerprinting of six available isolates by polymerase chain reaction using primers derived from the conserved region of the 16/23Sr RNA gene sequence and pulsed field gel electrophoresis revealed all to be unique strains. A case-control study comparing 7 S. maltophilia cases to 21 PD controls showed case patients to be younger and more likely to be on immuno-suppressive therapy. We conclude that S. maltophilia has emerged as an important cause of peritonitis in our continuous ambulatory PD population. Evidence to date suggests community acquisition with no evidence of a common source.

Correlation of Intraperitoneal Antibiotic Pharmacokinetics and Peritoneal Membrane Transport Characteristics

Objective

To identify correlations between the pharmacokinetic variables that describe drug disposition in peritoneal dialysis (PD) patients and the measures used to assess dialysis adequacy.

Design and Methods

This retrospective study re-evaluated data collected during previous pharmacokinetic studies for intraperitoneally administered cefazolin, ceftazidime, and gentamicin in continuous ambulatory peritoneal dialysis (CAPD) patients, and intravenous cefazolin and tobramycin in automated PD patients. Pharmacokinetic variables were compared to creatinine clearance (CCr), Kt/V, and peritoneal equilibration test data using the Pearson product correlation coefficient ( r).

Results

Prominent correlations were found between renal CCr and renal Kt/V, with renal clearances of CAPD cefazolin and ceftazidime, and automated PD tobramycin and cefazolin ( r values ranged from 0.698 to 0.986; p < 0.05).

Conclusion

These findings support current peritonitis treatment recommendations that patients with residual renal function may require higher doses or more frequent drug administration.

Predictors of Outcome following Bacterial Peritonitis in Peritoneal Dialysis

Objective

No studies have been done to examine factors that predict the outcome of bacterial peritonitis during peritoneal dialysis (PD), beyond the contribution of the organism causing the peritonitis, concurrent exit-site or tunnel infection, and abdominal catastrophes.

Design

In this study we examined several clinical and laboratory parameters that might predict the outcome of an episode of bacterial peritonitis. Between March 1995 and July 2000, we identified 399 episodes of bacterial peritonitis in 191 patients on dialysis.

Results

There were 260 episodes of gram-positive peritonitis, 99 episodes of gram-negative peritonitis, and 40 episodes of polymicrobial peritonitis. Gram-positive peritonitis had a significantly higher resolution rate than either polymicrobial peritonitis or gram-negative peritonitis. Staphylococcus aureus episodes had poorer resolution than other gram-positive infections. Nonpseudomonal peritonitis had a better outcome than Pseudomonas aeruginosa episodes. Among all the gram-negative infections, Serratia marcescens had the worst outcome. Episodes associated with a purulent exit site had poor outcome only on univariate analysis. For those peritonitis episodes in which the PD fluid cell count was > 100/μL for more than 5 days, the nonresolution rate was 45.6%, compared to a 4.2% nonresolution rate when the cell count returned to 100/μL or less in less than 5 days. Those patients that had a successful outcome had been on continuous ambulatory PD for a significantly shorter period of time than those patients that had nonresolution. The nonresolution rate for those patients that had been on PD for more than 2.4 years was 24.4%, compared to 16.5% for those that had been on PD for less than 2.4 years ( p = 0.05).

Conclusion

The duration of PD and the number of days the PD effluent cell count remained > 100/μL were the only factors that independently predicted the outcome of an episode of peritonitis. Caucasians seem to have a higher nonresolution (failure) rate compared to Blacks. Other variables, such as the number of peritonitis episodes before the episode in question, vancomycin-based initial empiric treatment, serum albumin level, total lymphocyte count and initial dialysate white blood cell count, age, sex, diabetes, previous renal transplantation, and the use of steroids did not affect the outcome of peritonitis.

Comparison of Peritoneal Fluid Culture Results from Adults and Children Undergoing Capd

Background

Peritonitis is a common complication in patients with end-stage renal disease treated by continuous ambulatory peritoneal dialysis (CAPD). Empirical treatment is based on the organisms that are most frequently isolated and their susceptibilities.

Objective

To analyze and then compare peritoneal fluid culture results from adult and pediatric patients on CAPD, with respect to micro-organisms and antimicrobial susceptibilities.

Design

Three-year retrospective review of peritoneal fluid cultures from adults and children on CAPD.

Results

We isolated 481 organisms from 378 peritoneal fluid specimens, collected from 135 patients (45 children, 90 adults). There were 191 episodes of peritonitis in children (mean 4.2 ± 3.5, range 1 – 15) compared to 187 in adults (2.1 ± 1.9, range 1 – 10) ( p < 0.001). Two or more episodes occurred in 30 of 45 children (67%) compared to 33 of 90 adults (37%) ( p < 0.001). The number of different organisms/patient as well as the total number of isolates/patient were significantly greater in children (respectively, 2.8 ± 2.3, range 1 – 12; and 5.3 ± 5.2, range 1 – 27) than in adults (2.0 ± 1.3, range 1 – 6; and 2.7 ± 2.4, range 1 – 10) ( p < 0.005). After Staphylococcus epidermidis, S. aureus was the most frequently isolated organism, occurring in 18% of episodes in adults and 12% of episodes in children ( p < 0.01). Twenty-two of 33 fungal isolates (67%) in children were Candida parapsilosis compared to 3 of 24 (12%) in adults ( p < 0.001). Subanalysis of multiple episodes revealed that Pseudomonas and Candida occurred significantly more often in children ( p < 0.01), whereas S. aureus occurred more often in adults ( p < 0.001). In polymicrobial episodes S. epidermidis occurred more often in adults ( p < 0.05). Significant differences in susceptibilities to ampicillin, ceftriaxone, chloramphenicol, and gentamicin were found between children and adults ( p < 0.05 – 0.001).

Conclusions

CAPD-associated peritonitis occurs significantly more often in children than adults. Significant differences in microbial etiology and susceptibilities were found between pediatric and adult patients. Each dialysis unit should periodically analyze peritoneal fluid culture results from its CAPD patients. These data can then be used for optimization of empirical antimicrobial therapy of peritonitis.

Colonization-Resistant Antimicrobial-Coated Peritoneal Dialysis Catheters: Evaluation in a Newly Developed Rat Model of Persistent Pseudomonas Aeruginosa Peritonitis

Objective

Development of a rat model of persistent peritonitis and evaluation of the ability of liposomal ciprofloxacin hydrogel-coated silicone to resist colonization.

Design

A newly developed model of persistent Pseudomonas aeruginosa peritonitis to compare the ability of liposomal ciprofloxacin hydrogel (LCH)-coated silicone versus plain silicone for resistance to bacterial colonization.

Animals

Male Sprague–Dawley rats.

Results

Inoculating the peritoneum of rats with 1 mL 0.5% agar containing 106 colony-forming units (cfu)/mL P. aeruginosa in the presence of a plain silicone coupon resulted in persistent peritonitis for at least 7 days. Plain silicone coupons in all 40 rats were colonized (median 2.54 × 103 cfu/cm2; range 5.0 × 101 – 1.0 × 106 cfu/cm2) and peritoneal washings were consistently culture-positive. In contrast, the LCH coupons removed after 7 days from the 40 test rats were sterile, as were the peritoneal washings, and there was no evidence of peritonitis. Blood cultures were negative in both groups.

Conclusions

Liposomal ciprofloxacin hydrogel-coated silicone resists colonization in this rat model of persistent P. aeruginosa peritonitis.

Comparison of Vancomycin versus Cefazolin as Initial Therapy for Peritonitis in Peritoneal Dialysis Patients

The incidence of peritonitis ranges from 1 episode every 24 patient treatment months to 1 episode every 60 patient treatment months [Keane WF, et al. ISPD Guidelines/Recommendations. Adult peritoneal dialysis-related peritonitis treatment recommendations: 2000 update. Perit Dial Int 2000; 20:396–411.]. Gram-positive organisms account for over 80% of continuous ambulatory peritoneal dialysis (PD)-associated peritonitis. Recent fear of vancomycin-resistant enterococci (VRE) has prompted suggestions of limiting vancomycin use.

Fifty-one episodes of peritonitis in 30 patients studied over 2 years were evaluated. Cloudiness of the PD fluid and/or abdominal pain were considered suggestive of peritonitis and were confirmed by cell count and culture. Baseline cell count, Gram stain, and cultures were obtained, with periodic follow-up. Patients were randomized to receive either vancomycin 1 g/L intraperitoneally (IP) as loading dose, repeated on day 5 or day 8, depending on residual renal function, for 2 weeks, or cefazolin 1 g in the first PD bag and continued with 125 mg/L every exchange for 2 or 3 weeks, depending on culture results. All patients also received gentamicin 40 mg IP every day until the culture results were available. A similar randomized trial comparing vancomycin and cefazolin in the past used a lower concentration of cefazolin 50 mg/L [Flanigan MJ, Lim VS. Initial treatment of dialysis associated peritonitis: a controlled trial of vancomycin versus cefazolin. Perit Dial Int 1991; 11:31–7.].

Peritoneal dialysate fluid cultures revealed 31 (60.7%) gram-positive organisms, 7 (13.7%) gram-negative organisms, and 2 (3.9%) cultured yeast; 11 (21.5%) cultures yielded no growth.

The incidence of peritonitis at our center was 1 episode every 42 patient treatment months. No case of VRE was noted. There was no statistical difference in clinical response or relapse rate for the two protocols. It was the authors’ and nurses’ observation that patient compliance and satisfaction was better with vancomycin, and the cost per treatment was 23% less than cefazolin. Based on these data we believe vancomycin should still be considered for first-line treatment of PD-associated peritonitis.

Recurrent Infection and Catheter Loss in Patients on Continuous Ambulatory Peritoneal Dialysis

Objective

To elucidate the factors leading to catheter loss from recurrent infection in patients on continuous ambulatory peritoneal dialysis (CAPD).

Design

All catheters removed from patients were prospectively examined for infection.

Setting

CAPD unit in large tertiary-care general hospital.

Patients

Sixty-five consecutive patients undergoing catheter removal for whatever cause; 20 catheters rejected because of desiccation or contamination in transit.

Interventions

None.

Main Outcome Measures

Micro-organisms linked to catheter removal; their locations on removed catheters.

Results

Of 45 catheters removed between January 1994 and August 1995, 26 were infected: 13/26 infections were caused by Staphylococcus aureus and 7/26 by Pseudomonas aeruginosa. In only one case was S. epidermidis associated with catheter removal. The most striking finding was that the inner cuff harbored large numbers of the infecting organisms, even when antibiotics had eradicated them from the peritoneal cavity and exit site, where present, and the catheter lumen.

Conclusion

The importance of S. aureus and Ps. aeruginosa rather than S. epidermidis in catheter loss due to relapsing infection is confirmed. Persistence of the causative organisms in the inner cuff is a likely explanation for relapse after treatment, and might be due to the predominantly intraperitoneal administration of antibiotics. A clinical trial of the effect on catheter retention of empirical use of systemic or oral agents that give high tissue levels and are active against intracellular microorganisms, along with recommended intraperitoneal regimens, is indicated.

Trends in CAPD Technique Failure: Canada, 1981–1997

Objective

Although important enhancements to continuous ambulatory peritoneal dialysis (CAPD) have occurred since its inception, few studies have explicitly evaluated trends over time in CAPD technique failure rates. To assist in quantifying the net benefit of improvements to CAPD for patient outcomes, we examined trends in technique failure rates among Canadian CAPD patients.

Patients

Patients initiating renal replacement therapy on CAPD ( n = 7110) between 1981 and 1997.

Main Outcome Measures

Technique failure ( i.e., switch to hemodialysis).

Results

Total follow-up was 12 831 patient-years (pt-yr). There were 1976 technique failures, for a crude CAPD failure rate of 154.0/1000 pt-yr. Technique failure rate ratios (RR) estimated using Poisson regression and adjusted for age, gender, race, province, primary renal diagnosis, and follow-up time, were significantly reduced for the 1990–93 [RR = 0.75, 95% confidence interval (CI) = (0.68, 0.83)], 1994–95 [RR = 0.83, CI (0.75, 0.93)], and 1996–97 [RR = 0.78, CI (0.70, 0.87)] calendar periods relative to 1981–89 (RR = 1, reference). Among cause-specific technique failure rates, the greatest improvement was observed for peritonitis-attributable technique failure, with RR = 0.46, CI (0.41, 0.50) for 1990–97 relative to 1981–89. However, rates of technique failure due to inadequate dialysis were significantly elevated for the 1990–97 period [RR = 1.68, CI (1.44, 1.96)].

Conclusions

The collection of more detailed data on practice patterns would enable future studies to elucidate the cause-and-effect relationship between CAPD descriptors and technique failure, and hence assist in clinical decision-making.

Intermittent Intravenous Piperacillin Pharmacokinetics in Automated Peritoneal Dialysis Patients

Background

Use of intermittent antibiotic dosing is increasing in the treatment of peritoneal dialysis (PD)-related peritonitis. We studied the pharmacokinetics of intravenous (IV) piperacillin in automated PD patients.

Patients and Methods

Eight patients (3 males, 5 females) were recruited and received a single IV dose of piperacillin (35 mg/kg actual body weight). Blood and dialysate samples were collected at the beginning, middle, and end of dwells 1 – 3 (on cycler), and end of dwells 4 – 5 (off cycler) for a 24-hour period. Baseline and 24-hour urine samples (nonanuric patients, n = 7) were collected. Pharmacokinetic parameters were calculated assuming a one-compartment model. Glomerular filtration rate (GFR) and piperacillin clearance (CL) values were normalized to 1.73 m2.

Results

The patients were 49.5 ± 10.1 years of age (mean ± SD) and had been receiving PD for a median of 3 months (range 2 – 66 months). Dwell times were 2.25 ± 0.06 hours on cycler and 7.26 ± 0.14 hours off cycler. Piperacillin half-life was not statistically different on or off the cycler (on cycler 1.99 ± 0.39 hr, off cycler 4.39 ± 5.4 hr; p = 0.12) and remained insignificant, even accounting for an outlier (on cycler 2.01 ± 0.41 hr, off cycler 2.54 ± 1.48 hr; p = 0.19). Piperacillin total CL (CLT) was 31.29 ± 6.02 mL/minute. Renal CL (CLR) and PD CL (CLPD) accounted for 8.8% and 16.8% of CLT; CLR correlated well with GFR (CLR = 0.86 GFR + 0.1; p < 0.000 03). Mean piperacillin serum and dialysate end-of-dwell concentrations were above minimum inhibitory concentration of susceptible organisms (8 μg/mL) for the three cycler exchanges only. Serum and dialysate concentrations predicted using a one-compartment model suggest that IV piperacillin 4000 mg would provide adequate concentrations for susceptible organisms over a 12-hour period.

Conclusion

The current IV piperacillin dosing recommendations of 4000 mg every 12 hours for PD-related peritonitis are appropriate for patients on automated PD. Intermittent intraperitoneal piperacillin is not recommended.

The Risk of Infection and Peritoneal Catheter Loss from Implant Procedure Exit-Site Trauma

Objective

To evaluate the role of skin and subcutaneous tissue trauma at the time of catheter implant procedure as a determinant of catheter loss from infectious complications.

Design

Nonrandomized study with prospective collection of data.

Patients

Consecutive patients were divided into three groups based upon how the catheter was exited through the skin: group 1, procedure involved pulling tubing, with a permanently bonded catheter adapter, through the exit-site wound ( n = 43); group 2, same as group 1 except exit wounds were closed around the catheter with a suture ( n = 20); group 3, procedure involved pulling only tubing through the exit wound ( n = 61).

Setting

Primary medical center for a health maintenance organization.

Main Outcome Measures

Log rank comparisons of Kaplan–Meier analyses of first occurrences of infectious events and overall catheter survival.

Results

The risk of first exit-site infection ( p < 0.001), tunnel infection ( p < 0.001), catheter infection-related peritonitis ( p < 0.001), and catheter loss ( p < 0.01) were greatest in group 1 with large exit wounds, and lowest in group 3 with small exit wounds.

Conclusions

The study demonstrates the importance of careful dissection and exit-site construction. The exit site should consist of the smallest hole possible that permits passage of only the tubing and leaves the skin snug around the catheter. The present report incriminates catheter designs employing permanently bonded adapters that result in large pericannular wounds that are prone to infection and catheter loss.

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.

Pharmacokinetics of Ceftazidime in CAPD-Related Peritonitis

Objective

The aim of this study was to measure and evaluate the appropriateness of the actual concentrations of serum and dialysate ceftazidime in Thai continuous ambulatory peritoneal dialysis (CAPD) patients.

Design

Prospective and descriptive study of patients treated following the International Society for Peritoneal Dialysis (ISPD) 2000 recommendation for the empiric therapy of CAPD-related peritonitis.

Setting

Institutional level of clinical care.

Patients

CAPD-related peritonitis patients were diagnosed by dialysate effluent white blood cell count of more than 100/mm3and polymorphonuclear leukocytes of at least 50%. There were 10 patients, all at least 18 years of age, entered; all completed the study.

Intervention

In accordance with the ISPD 2000 recommendations, the antibiotic regimen comprised continuous intraperitoneal (IP) cefazolin and once-daily IP ceftazidime. Cefazolin was administered as loading and continuous maintenance doses of 500 and 125 mg/L dialysate respectively. Ceftazidime (20 mg/kg body weight) was given IP once daily. Duration of treatment was 96 hours.

Main Outcome Measures

Serum and dialysate effluent samples of the 10 CAPD patients with peritonitis were measured for ceftazidime levels, which were used for the development of pharmacokinetic equations that could predict drug concentrations at any treatment time.

Results

Following ceftazidime administration as in the ISPD 2000 recommendation, serum ceftazidime levels were above 8 μg/mL, the minimum inhibitory concentration (MIC) recommended by NCCLS, throughout 24 hours. Dialysate ceftazidime levels were below the MIC for total periods of 4.19 and 6.26 hours in day 1 and day 4 respectively. The clinical response rate to the empiric regimen was 90%.

Conclusions

Once-daily IP administration of ceftazidime according to the ISPD 2000 recommendation could not provide adequately therapeutic levels of ceftazidime in dialysate throughout 24 hours. Despite this finding and the poor post-antibiotic property of ceftazidime, the empiric regimen including once-daily IP ceftazidime could yield good clinical outcome.

Does a High Peritoneal Transport Rate Reflect a State of Chronic Inflammation?

Objective

It has recently been reported that a high peritoneal transport rate was associated with increased mortality in continuous ambulatory peritoneal dialysis (CAPD) patients. One possible explanation is that a high peritoneal transport rate might be caused by a state of chronic inflammation, which also per se might result in increased mortality. Therefore, in this study we investigated whether high peritoneal transport rate patients are in a state of chronic inflammation.

Methods

The study included 39 clinically stable peritoneal dialysis patients (free of peritonitis) who had been on PD for more than 3 months (16.8 ± 11.8 months). Seven patients were treated with continuous cycling peritoneal dialysis (CCPD) and the others were on CAPD. A 4-hour standard peritoneal equilibration test (PET) using 2.27% glucose solution was performed in each patient. Dialysate samples at 4 hours and blood samples at 2 hours were measured for interleukin-1β (IL-β), tumor necrosis factoroc (TNFα), C-reactive protein (CRP), and hyaluronan as markers of inflammation.

Results

There was no significant correlation between dialysate/plasma (D/P) creatinine (0.82 ± 0.15, range 0.51 - 1.15) and blood concentrations of IL-1β (11.2 ng/L, range <5 - 65.9 ng/L), TNFα (12.1 ng/L, range <5 - 85.4 ng/L), CRP (<10 mg/L, range <10 - 76 mg/L), nor with the blood hyaluronan concentration (165 μg/L, range 55 - 955 μg/L). The dialysate concentrations of IL-1β and TNFα were below the detectable level in most of the samples. Although dialysate hyaluronan concentration (334 μg/L, range 89 - 1100 μg/L) was correlated with D/P creatinine ( r = 0.36, p < 0.05), there was no correlation between the total amount of hyaluronan in the effluent and D/P creatinine. However, a significant correlation was found between serum hyaluronan concentration and glomerular filtration rate (GFR) ( r = -0.49, p < 0.005); GFR also tended to be correlated with serum TNFα ( r = -0.31, p = 0.058) but not with serum IL-1β and serum CRP.

Conclusion

Our results suggest that a high peritoneal transport rate is not necessarily related to a state of chronic inflammation in CAPD patients. The high mortality rate observed in high transporters may relate to other issues, such as fluid balance or abnormal nutrition and metabolism, rather than to chronic inflammation.

A Retrospective Study of Seven Cases of Candida Parapsilosis Peritonitis in CAPD Patients: The Therapeutic Implications

Background

Candida peritonitis accounts for the majority of fungal peritonitis in continuous ambulatory peritoneal dialysis (CAPD), but the Candida species were not routinely subtyped in previous studies. The clinical course and the outcome of Candida parapsilosis peritonitis remain unclear.

Objective

To study the clinical course and outcome of C. parapsilosis peritonitis in CAPD patients.

Setting

Peritoneal dialysis unit in a regional hospital.

Patients and Design

A retrospective study on seven cases of C. parapsilosis peritonitis occurring in a single center over 3 years.

Results

The 7 patients included 4 males and 3 females. Their mean age was 62 ± 11.5 years. Two (29%) were diabetic. Three (43%) had a history of preceding peritonitis and 5 (71%) had received broad spectrum antibiotic within the previous 1 month. All presented with cloudy dialysate, abdominal pain, and fever. The mean dialysate white cell count was 300 ± 168/mm3 with a predominance of neutrophils (81.4% ± 13.1%). The mean time from onset of symptoms to diagnosis was 5.7 ± 3.1 days. All had been treated with immediate catheter removal within 24 hours of diagnosis and antifungal therapy, including oral fluconazole, intravenous (IV) amphotericin, or their sequential combination. Environmental samplings were negative for C. parapsilosis. The overall complication rate was exceptionally high (71%), with three (43%) complicated by abscess formation requiring surgical drainage, one peritoneal adhesion (14%), and one mortality (14%). In the end, only two (29%) could resume CAPD.

Conclusions

The outcome of this study group appeared worse than those previously described in the literature, and the optimal treatment for this group of patients remains unclear.

Treatment and outcome of Peritonitis in Automated Peritoneal Dialysis, using a Once-Daily Cefazolin-Based Regimen

Objective

We determined the effectiveness of a once-daily cefazolin-based regimen in treating automated peritoneal dialysis (APD) peritonitis.

Design

We carried out a retrospective analysis of all APD peritonitis episodes treated with a once-daily cefazolin protocol.

Setting

The study was performed in a peritoneal dialysis unit in a tertiary care hospital.

Patients and Methods

We studied 60 episodes of primary peritonitis in 40 patients on APD. Each patient was treated with a vancomycin-free regimen consisting of intraperitoneal cefazolin (1.5 g IP) with gentamicin IP administered in the daytime exchange. The main outcome measures were successful treatment of peritonitis, removal of peritoneal catheter, relapse of peritonitis, and patient death.

Results

Gram-positive infections occurred in 35 episodes (58.3%), gram-negative infections in 10 episodes (16.7%), culture-negative infections in 14 episodes (23.3%), and a yeast infection in 1 episode (1.7%). Of the 60 episodes, 47 (78.3%) were successfully treated. In 10 episodes (16.7%), catheters were removed (9 for treatment failure, 1 for yeast infection). Four patients (8%) had a relapse of infection within 4 weeks of completing antibiotic therapy. One patient (1.7%) died.

Conclusions

Our results demonstrate that once-daily cefazolin with gentamicin IP is an effective treatment for APD peritonitis, with the advantage of being easy to administer and enabling patients to remain on APD during treatment.