Practice variations in antibiotic administration for the management of peritonitis in patients on automated peritoneal dialysis in Australia and New Zealand

In the absence of guidelines on the management of peritoneal dialysis (PD)-associated peritonitis in patients on automated peritoneal dialysis (APD), variations in clinical practice potentially exist between PD units that could affect clinical outcomes. This study aimed to document the current practices of treating PD-associated peritonitis in patients on APD across Australia and New Zealand and the reasons for practice variations using a cross-sectional online survey. Of the 62 PD units, 34 medical leads (55%) responded to the survey. When treating APD-associated peritonitis, 21 units (62%) continued patients on APD and administered intraperitoneal (IP) antibiotics in manual daytime exchanges; of these, 17 (81%) considered allowing at least 6 h dwell time for adequate absorption of the IP antibiotics as an important reason for adding manual daytime exchange. Nine units (26%) temporarily switched patients from APD to continuous ambulatory peritoneal dialysis (CAPD); of these, five (55%) reported a lack of pharmacokinetic (PK) data for IP antibiotics in APD, four (44%) reported a shortage of APD-trained nursing staff to perform APD exchanges during hospitalisation and three (33%) reported inadequate time for absorption of IP antibiotics on APD as important reasons for their practice. Four units (12%) continued patients on APD and administered IP antibiotics during APD exchanges; of these, three (75%) believed that PK data available in CAPD could be extrapolated to APD. This study demonstrates wide variations in the management of APD-associated peritonitis in Australia and New Zealand; it points towards the lack of PK on antibiotics used to treat peritonitis as an important reason underpinning practice variations.

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.

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.

Pharmacokinetics of Intraperitoneal Cefepime in Automated Peritoneal Dialysis

Objective

This study determined the pharmacokinetics of intraperitoneal (IP) cefepime in automated peritoneal dialysis (APD) patients.

Design and Methods

A prospective pharmacokinetic study was performed in 6 noninfected adult APD patients. All patients were administered a single IP dose of cefepime (15 mg/kg) over a 6-hour dwell. Patients then underwent a fixed APD regimen consisting of the first 6-hour dwell, followed by an 8-hour dialysate-free period and a subsequent series of 3 overnight APD exchanges. Blood and dialysate samples were collected at t = 0, 1, 2, 4, 6 (end of dwell), and 24 hours. Any urine produced during the study period was collected. Cefepime concentrations in serum, dialysate, and urine were determined by liquid chromatography mass spectrometry. Pharmacokinetic parameters were calculated assuming a mono-exponential model.

Results

One hour after IP administration, serum cefepime levels exceeded the minimum inhibitory concentration (8 μg/mL) for susceptible organisms. The mean serum and dialysate concentrations at 24 hours were 15.8 ± 3.6 and 6.2 ± 2.3 μg/mL respectively. Bioavailability was 84.3% ± 6.2%, volume of distribution 0.34 ± 0.07 L/kg, and serum half-life 13.8 ± 3.2 hours. Total, peritoneal, and renal clearances were 16.5 ± 4.4, 4.3 ± 0.7, and 3.5 ± 2.5 mL/minute, respectively.

Conclusions

IP cefepime dosed at 15 mg/kg resulted in adequate serum concentrations in APD patients at 24 hours post dose. Pharmacokinetic predictions suggest that most APD and CAPD patients would achieve adequate serum cefepime concentrations if treated with standard doses of 1000 mg given IP once daily. Patients using APD regimens different from that used in this study, anuric patients, and those with significant residual renal function may require a more individualized approach.

Effective Treatment of Peritoneal Dialysis-Associated Peritonitis with Cefazolin and Ceftazidime in Children

Objective

To evaluate the use of the combination of cefazolin and ceftazidime for initial treatment of peritoneal dialysis (PD)-related peritonitis in pediatric patients.

Design

Retrospective nonrandomized study.

Setting

Pediatric dialysis units of the University Medical Center of Utrecht and Nijmegen, The Netherlands.

Patients

40 children (median age 5.4 years) who were treated with PD during the study period of 4.5 years.

Interventions

All 50 episodes of peritonitis that occurred during the study period were evaluated by review of medical records. Patients were given intraperitoneal ceftazidime 500 mg/L dialysis fluid, and cefazolin 500 mg/L as a loading dose, followed by a maintenance dose of ceftazidime 125 mg/L and cefazolin 100 mg/L, intraperitoneally, 4 times daily. Antibiotics were continued for 14 days.

Results

After identification of the causative microorganism, one of the antibiotics was discontinued in 34 cases, and the antibiotic schedule was adapted in 2 cases. All cases were initially cured within 3 days. In 5 cases (10%), there was a peritonitis with the same organism recurring within 2 weeks after completion of treatment. There were 4 cases of PD-related peritonitis caused by pseudomonas, all of which were cured.

Conclusions

The antibiotic combination of cefazolin and ceftazidime is effective for the initial therapy of PD-related peritonitis in children. The toxic complications of aminoglycosides are avoided with this combination.

Influence of Peritoneal Dialysate Flow Rate on the Pharmacokinetics of Cefazolin

Objective

To determine the impact of dialysate flow rate (DFR) on cefazolin pharmacokinetics (PK) in peritoneal dialysis (PD) patients.

Methods

A meta-analysis of published reports, identified by MEDLINE search (1966-2002) and other sources, containing information on cefazolin PK data in PD patients was conducted. Data were analyzed based upon low DFR (≤ 5.50 mL/minute) or high DFR (> 5.50 mL/minute). Data available were from North American (NA) ( n = 45) and Singaporean ( n = 10) patients. Complete data sets were available for 33 patients (CDS patients). Data were analyzed with respect to data origin and data set completeness: all patients (ALL), NA, and CDS. Analysis of log-transformed cefazolin PK data was performed to determine coefficient of determination ( r2) between DFR and cefazolin elimination rate constant (kel), clearance total (ClT), and clearance peritoneal (ClPD). Clearance total data were extrapolated to DFR observed in continuous flow PD.

Results

Published literature provided data on 55 PD patients (12 high DFR, 43 low DFR). Regardless of data origin (ALL, NA, or CDS), a prominent coefficient of determination ( p < 0.0001) existed between DFR and all cefazolin PK data except ClPD. The p value for DFR correlation to ClPD was 0.953, 0.011, and 0.036 for ALL, NA, and CDS patients, respectively. Cefazolin ClT and ClPD increased at higher DFRs.

Conclusion

These findings demonstrate that an increased DFR leads to an increased rate of cefazolin clearance in NA PD patients. The impact of Asian descent on cefazolin ClPD warrants further investigation. Clinicians dosing cefazolin in PD patients using a higher DFR than that used to determine cefazolin PK should use increased doses or prescribe lower/comparable DFRs. Data are not yet available for patients prescribed very high DFRs ( e.g., continuous flow PD); extrapolation of our results demonstrates significant influences on clearance and risk for underdosing.

Intraperitoneal cefazolin and ceftazidime during short-dwell exchange in peritoneal dialysis patients with peritonitis

BACKGROUND

Intraperitoneal (IP) cefazolin and ceftazidime during the short-dwell (≤ 2 h) automated exchange has been shown to provide adequate dialysate and plasma concentrations for up to 24 h in peritoneal dialysis (PD) patients without peritonitis. This study aimed to evaluate plasma and dialysate concentration of this novel IP cefazolin and ceftazidime regimen during the first 24 h in PD patients with peritonitis.

METHODS

Cefazolin and ceftazidime (2500 mg each) were added to in to a 5-L bag containing 2.5% of dextrose PD fluid which was placed on the warmer of PD cycling machine. Patients underwent five exchanges of 2-L PD fluid over 10 h by the PD cycling machine without last fill or additional dwell. Plasma samples and dialysate samples were collected over 24 h. Cefazolin and ceftazidime concentrations in plasma and dialysate were determined by high-performance liquid chromatography.

RESULTS

Seven PD patients with peritonitis participated in this study. Plasma cefazolin and ceftazidime levels increased substantially within the first few hours, peaked around 6-10 h, and sustained well above the target plasma concentrations (10 mg L^-1 for cefazolin and 16 mg L^-1 for ceftazidime) until 24 h. Dialysate cefazolin and ceftazidime levels were sustained above the target peritoneal concentrations (2 mg L^-1 for cefazolin and 8 mg L^-1 for ceftazidime) throughout the PD session except in some samples which the antibiotics levels were unusually low, probably from beta-lactamase activity.

CONCLUSIONS

IP cefazolin and ceftazidime during the short-dwell automated exchange could provide adequate dialysate and plasma concentrations in peritonitis patients. This novel regimen is a promising regimen for peritonitis in PD patients.

Short-Dwell Cycling Intraperitoneal Cefazolin plus Ceftazidime in Peritoneal Dialysis Patients

Background

Current guidelines suggest that intraperitoneal (IP) antibiotics should be administered only in a long peritoneal dialysis (PD) dwell (≥ 6 hours). The long dwell might result in low ultrafiltration and volume overload. We aim to examine plasma and dialysate concentration of cefazolin and ceftazidime after IP administration in a short-dwell (≤ 2 hours) automated cycling exchange.

Methods

Stable PD patients without peritonitis were invited to participate in the present study. Patients underwent 5 2-liter exchanges of PD fluid over 10 hours by the PD cycling machine without last fill or additional dwell. Cefazolin and ceftazidime (20 mg/kg each) were added to the first 5-liter bag of 2.5% dextrose PD fluid that was placed on the warmer of the PD cycling machine. Plasma samples were collected at 12 time-points over 24 hours. Dialysate samples from each exchange were also collected. Antibiotic concentrations in plasma and dialysate were then determined by high-performance liquid chromatography (HPLC).

Results

Six stable PD patients without peritonitis participated in the study. Dialysate cefazolin and ceftazidime were consistently high throughout the PD session in all patients (26 - 360 mg/L). Plasma cefazolin and ceftazidime exceeded the minimal inhibitory concentration (MIC) for susceptible organisms (≤ 8 mg/L) within 2 hours (cefazolin 28.5 ± 8.0 and ceftazidime 12.5 ± 3.4 mg/L), peak at 10 hours (51.1 ± 14.1 and 23.0 ± 5.2 mg/L) and sustained well above the MIC at 24 hours (42.0 ± 9.6 and 17.1 ± 3.1 mg/L).

Conclusions

The short-dwell cycling IP cefazolin and ceftazidime could provide adequate plasma concentration for up to 24 hours. Daily short-dwell cycling IP cefazolin and ceftazidime might be used to treat peritonitis in PD patients already using a PD cycling machine as well as selected continuous ambulatory PD (CAPD) patients who need shorter dwells during peritonitis due to increasing peritoneal solute transport.

Pharmacokinetics of Intraperitoneal Cefalothin and Cefazolin in Patients Being Treated for Peritoneal Dialysis-Associated Peritonitis

♦

BACKGROUND

The standard treatment of peritoneal dialysis (PD)-associated peritonitis (PD-peritonitis) is intraperitoneal (IP) administration of antibiotics. Only limited data on the pharmacokinetics and appropriateness of contemporary dose recommendations of IP cefalothin and cefazolin exist. The aim of this study was to describe the pharmacokinetics of IP cefalothin and cefazolin in patients treated for PD-peritonitis. ♦

METHODS

As per international guidelines, IP cefalothin or cefazolin 15 mg/kg once daily was dosed with gentamicin in a 6-hour dwell to patients with PD-peritonitis during routine care. Serial plasma and PD effluent samples were collected over the first 24 hours of therapy. Antibiotic concentrations were quantified using a validated chromatographic method with pharmacokinetic analysis performed using a non-compartmental approach. ♦

RESULTS

Nineteen patients were included (cefalothin n = 8, cefazolin n = 11). The median bioavailability for both antibiotics exceeded 92%, but other pharmacokinetic parameters varied markedly between antibiotics. Both antibiotics achieved high PD effluent concentrations throughout the antibiotic dwell. Cefazolin had a smaller volume of distribution compared with cefalothin (14 vs 40 L, p = 0.003). The median trough total plasma antibiotic concentration for cefazolin and cefalothin during the dwell differed (plasma 56 vs 13 mg/L, p < 0.0001) despite a similar concentration in PD effluent (37 vs 38 mg/L, p = 0.58). Lower antibiotic concentrations were noted during PD dwells not containing antibiotic, particularly cefalothin, which was frequently undetectable in plasma and PD effluent. The median duration that the unbound antibiotic concentration was above the minimum inhibitory concentration (MIC) was approximately 13% (plasma) and 25% (IP) for cefalothin, and 100% (plasma and IP) for cefazolin, of the dosing interval. ♦

CONCLUSIONS

When IP cefalothin or cefazolin is allowed to dwell for 6 hours, sufficient PD effluent concentrations are present for common pathogens during this time. However, with once-daily IP dosing, in contrast to cefazolin, there is a risk of subtherapeutic plasma and PD effluent cefalothin concentrations, so more frequent dosing may be required.

Treatment for peritoneal dialysis-associated peritonitis

BACKGROUND

Peritonitis is a common complication of peritoneal dialysis (PD) that is associated with significant morbidity including death, hospitalisation, and need to change from PD to haemodialysis. Treatment is aimed to reduce morbidity and recurrence. This is an update of a review first published in 2008.

OBJECTIVES

To evaluate the benefits and harms of treatments for PD-associated peritonitis.

SEARCH METHODS

For this review update we searched the Cochrane Renal Group's Specialised Register to March 2014 through contact with the Trials Search Co-ordinator using search terms relevant to this review. Studies contained in the Specialised Register are identified through search strategies specifically designed for CENTRAL, MEDLINE and EMBASE, and handsearching conference proceedings.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and quasi-RCTs assessing the treatment of peritonitis in PD patients (adults and children). We included any study that evaluated: administration of an antibiotic by different routes (e.g. oral, intraperitoneal (IP), intravenous (IV)); dose of an antibiotic agent; different schedules of administration of antimicrobial agents; comparisons of different regimens of antimicrobial agents; any other intervention including fibrinolytic agents, peritoneal lavage and early catheter removal.

DATA COLLECTION AND ANALYSIS

Multiple authors independently extracted data on study risk of bias and outcomes. Statistical analyses were performed using the random effects model. We expressed summarised treatment estimates as a risk ratio (RR) with 95% confidence intervals (CI) for dichotomous outcomes and mean difference (MD) with 95% CI for continuous outcomes.

MAIN RESULTS

We identified 42 eligible studies in 2433 participants: antimicrobial agents (36 studies); urokinase (4 studies), peritoneal lavage (1 study), and IP immunoglobulin (1 study). We did not identify any optimal antibiotic agent or combination of agents. IP glycopeptides (vancomycin or teicoplanin) had uncertain effects on primary treatment response, relapse rates, and need for catheter removal compared to first generation cephalosporins, although glycopeptide regimens were more likely to achieve a complete cure (3 studies, 370 episodes: RR 1.66, 95% CI 1.01 to 2.72). For relapsing or persistent peritonitis, simultaneous catheter removal and replacement was better than urokinase at reducing treatment failure rates (RR 2.35, 95% CI 1.13 to 4.91) although evidence was limited to a single small study. Continuous and intermittent IP antibiotic dosing schedules had similar treatment failure and relapse rates. IP antibiotics were superior to IV antibiotics in reducing treatment failure in one small study (RR 3.52, 95% CI 1.26 to 9.81). Longer duration treatment (21 days of IV vancomycin and IP gentamicin) had uncertain effects on risk of treatment relapse compared with 10 days treatment (1 study, 49 patients: RR 1.56, 95% CI 0.60 to 3.95) although may have increased ototoxicity.In general, review conclusions were based on a small number of studies with few events in which risk of bias was generally high; interventions were heterogeneous, and outcome definitions were often inconsistent. There were no RCTs evaluating optimal timing of catheter removal and data for automated PD were absent.

AUTHORS' CONCLUSIONS

Many of the studies evaluating treatment of PD-related peritonitis are small, out-dated, of poor quality, and had inconsistent definitions and dosing regimens. IP administration of antibiotics was superior to IV administration for treating PD-associated peritonitis and glycopeptides appear optimal for complete cure of peritonitis, although evidence for this finding was assessed as low quality. PD catheter removal may be the best treatment for relapsing or persistent peritonitis.Evidence was insufficient to identify the optimal agent, route or duration of antibiotics to treat peritonitis. No specific antibiotic appears to have superior efficacy for preventing treatment failure or relapse of peritonitis, but evidence is limited to few trials. The role of routine peritoneal lavage or urokinase is uncertain.

Effects of peritoneal dialysis on pharmacotherapy: a deductive pharmacokinetic-model approach to predict drug concentration profiles in plasma and peritoneal fluid

The aim of this study was to present a deductive compartment pharmacokinetic (PK) model to predict the concentration profiles of drugs in plasma and peritoneal fluid in peritoneal dialysis (PD) rats. PK parameters of model drugs in normal and experimentally induced acute renal failure (ARF) rats not undergoing PD were obtained inductively in a common regression manner with a two-compartment model. In PD normal and ARF rats, PK parameters relating to the transfer of drugs to the peritoneal dialysate and the progress of renal failure were deductively modified to simulate the drug concentration-time profiles in plasma and in the peritoneal fluid in PD rats. The deductively introduced modifiers were the volume of distribution in the peripheral compartment, plasma protein binding, and solvent movement factor to the peritoneal fluid. Predicted profiles of tolbutamide, propranolol and cefazolin in PD normal and ARF rats were compared with the corresponding observed data. This minimal deductive approach yielded satisfactory accuracy in the prediction of both the plasma and peritoneal fluid concentrations of tolbutamide and propranolol.

Pharmacokinetics of clindamycin in the plasma and dialysate after intraperitoneal administration of clindamycin phosphoester to patients on continuous ambulatory peritoneal dialysis: an open-label, prospective, single-dose, two-institution study

We evaluated the pharmacokinetics of clindamycin and the dose of clindamycin phosphate necessary to treat peritonitis after intraperitoneal administration of clindamycin phosphate to patients on continuous ambulatory peritoneal dialysis (CAPD). This was an open-label, prospective, single-dose study conducted at the two levels of institutional clinical care in South Korea. Twelve patients (six men and six women; all older than 25 years), mean CAPD duration of 38.2 months with various origins without peritonitis, received 600 mg clindamycin phosphate mixed with only the first 2-L dialysate (1.5% dextrose). The 1.5%, 1.5%, 2.5% and 1.5% dextrose dialysates were serially exchanged every 6 hr. If patients were non-anuric, 24-hr urine samples were also collected. Clindamycin phosphate was incompletely activated to clindamycin in the dialysate. The clindamycin concentration in the dialysate was greater than the effective concentration (5 μg/mL) at 6.87 μg/mL up to 6 hr. So, 600 mg clindamycin phosphate per every 6 hr dialysate is effective for treatment of peritonitis. It has been reported that the clindamycin concentrations in the dialysate may be higher in CAPD patients with peritonitis. Thus, we can expect that intraperitoneal administration of <600 mg clindamycin phosphate per every 6 hr dialysate could be maintained over 5 μg/mL in patients with peritonitis. The transfer of clindamycin was unidirectional from the dialysate to the plasma.

A Monte Carlo analysis of peritoneal antimicrobial pharmacokinetics

Peritoneal dialysis-associated peritonitis (PDAP) can be treated using very different regimens of antimicrobial administration, regimens that result in different pharmacokinetic outcomes and systemic exposure levels. Currently, there is no population-level pharmacokinetic framework germane to the treatment of PDAP. We coupled a differential-equation-based model of antimicrobial kinetics to a Monte Carlo simulation framework, and conducted "in silico" clinical trials to explore the anticipated effects of different antimicrobial dosing regimens on relevant pharmacokinetic parameters (AUC/MIC and time greater than 5 ×MIC) and the level of systemic exposure.

Optimising intraperitoneal gentamicin dosing in peritoneal dialysis patients with peritonitis (GIPD) study

Background

Antibiotics are preferentially delivered via the peritoneal route to treat peritonitis, a major complication of peritoneal dialysis (PD), so that maximal concentrations are delivered at the site of infection. However, drugs administered intraperitoneally can be absorbed into the systemic circulation. Drugs excreted by the kidneys accumulate in PD patients, increasing the risk of toxicity. The aim of this study is to examine a model of gentamicin pharmacokinetics and to develop an intraperitoneal drug dosing regime that maximises bacterial killing and minimises toxicity.

Methods/Design

This is an observational pharmacokinetic study of consecutive PD patients presenting to the Royal Brisbane and Women's Hospital with PD peritonitis and who meet the inclusion criteria. Participants will be allocated to either group 1, if anuric as defined by urine output less than 100 ml/day, or group 2: if non-anuric, as defined by urine output more than 100 ml/day. Recruitment will be limited to 15 participants in each group. Gentamicin dosing will be based on the present Royal Brisbane & Women's Hospital guidelines, which reflect the current International Society for Peritoneal Dialysis Peritonitis Treatment Recommendations. The primary endpoint is to describe the pharmacokinetics of gentamicin administered intraperitoneally in PD patients with peritonitis based on serial blood and dialysate drug levels.

Discussion

The study will develop improved dosing recommendations for intraperitoneally administered gentamicin in PD patients with peritonitis. This will guide clinicians and pharmacists in selecting the most appropriate dosing regime of intraperitoneal gentamicin to treat peritonitis.

Trial Registration

ACTRN12609000446268

Treatment for peritoneal dialysis-associated peritonitis

BACKGROUND

Peritonitis is a common complication of peritoneal dialysis (PD) and is associated with significant morbidity. Adequate treatment is essential to reduce morbidity and recurrence.

OBJECTIVES

To evaluate the benefits and harms of treatments for PD-associated peritonitis.

SEARCH STRATEGY

We searched the Cochrane Renal Group's specialised register, the Cochrane Central Register of Controlled Trials (CENTRAL, in The Cochrane Library), MEDLINE, EMBASE and reference lists without language restriction. Date of search: February 2005

SELECTION CRITERIA

All randomised controlled trials (RCTs) and quasi-RCTs assessing the treatment of peritonitis in peritoneal dialysis patients (adults and children) evaluating: administration of an antibiotic(s) by different routes (e.g. oral, intraperitoneal, intravenous); dose of an antibiotic agent(s); different schedules of administration of antimicrobial agents; comparisons of different regimens of antimicrobial agents; any other intervention including fibrinolytic agents, peritoneal lavage and early catheter removal were included.

DATA COLLECTION AND ANALYSIS

Two authors extracted data on study quality and outcomes. Statistical analyses were performed using the random effects model and the dichotomous results were expressed as relative risk (RR) with 95% confidence intervals (CI) and continuous outcomes as mean difference (WMD) with 95% CI.

MAIN RESULTS

We identified 36 studies (2089 patients): antimicrobial agents (30); urokinase (4), peritoneal lavage (1) intraperitoneal (IP) immunoglobulin (1). No superior antibiotic agent or combination of agents were identified. Primary response and relapse rates did not differ between IP glycopeptide-based regimens compared to first generation cephalosporin regimens, although glycopeptide regimens were more likely to achieve a complete cure (3 studies, 370 episodes: RR 1.66, 95% CI 1.01 to 3.58). For relapsing or persistent peritonitis, simultaneous catheter removal/replacement was superior to urokinase at reducing treatment failure rates (1 study, 37 patients: RR 2.35, 95% CI 1.13 to 4.91). Continuous IP and intermittent IP antibiotic dosing had similar treatment failure and relapse rates. IP antibiotics were superior to IV antibiotics in reducing treatment failure (1 study, 75 patients: RR 3.52, 95% CI 1.26 to 9.81). The methodological quality of most included studies was suboptimal and outcome definitions were often inconsistent. There were no RCTs regarding duration of antibiotics or timing of catheter removal.

AUTHORS' CONCLUSIONS

Based on one study, IP administration of antibiotics is superior to IV dosing for treating PD peritonitis. Intermittent and continuous dosing of antibiotics are equally efficacious. There is no role shown for routine peritoneal lavage or use of urokinase. No interventions were found to be associated with significant harm.

Treatment of peritoneal dialysis-associated peritonitis: a systematic review of randomized controlled trials

BACKGROUND

Peritonitis frequently complicates peritoneal dialysis. Appropriate treatment is essential to reduce adverse outcomes. Available trial evidence about peritoneal dialysis peritonitis treatment was evaluated.

SELECTION CRITERIA FOR STUDIES

The Cochrane CENTRAL Registry (2005 issue), MEDLINE (1966 to February 2006), EMBASE (1985 to February 2006), and reference lists were searched to identify randomized trials of treatments for patients with peritoneal dialysis peritonitis.

INTERVENTIONS

Trials of antibiotics (comparisons of routes, agents, and dosing regimens), fibrinolytic agents, peritoneal lavage, and intraperitoneal immunoglobulin.

OUTCOMES

Treatment failure, relapse, catheter removal, microbiological eradication, hospitalization, all-cause mortality, and adverse reactions.

RESULTS

36 eligible trials were identified: 30 trials (1,800 patients) of antibiotics; 4 trials (229 patients) of urokinase; 1 trial of peritoneal lavage (36 patients); and 1 trial of intraperitoneal immunoglobulin (24 patients). No superior antimicrobial class was identified. In particular, glycopeptides and first-generation cephalosporins were equivalent (3 trials, 387 patients; relative risk [RR], 1.84; 95% confidence interval [CI], 0.95 to 3.58). Simultaneous catheter removal/replacement was superior to urokinase at decreasing treatment failures (1 trial, 37 patients; RR, 2.35; 95% CI, 1.13 to 4.91). Continuous and intermittent intraperitoneal antibiotic dosing were equivalent regarding treatment failure (4 trials, 338 patients; RR, 0.69; 95% CI, 0.37 to 1.30) and relapse (4 trials, 324 patients; RR, 0.93; 95% CI, 0.63 to 1.39). One trial showed superiority of intraperitoneal antibiotics over intravenous therapy.

LIMITATIONS

The method quality of trials generally was suboptimal and outcome definitions were inconsistent. Small patient numbers led to inadequate power to show an effect. Interventions, such as optimal duration of antibiotic therapy, were not evaluated.

CONCLUSIONS

Trials did not identify superior antibiotic regimens. Intermittent and continuous antibiotic dosing are equivalent treatment strategies.

Pharmacokinetics of intraperitoneal cefazolin and ceftazidime coadministered to CAPD patients

PURPOSE

Guidelines for empiric treatment of PD-related peritonitis published in 2000 recommend concurrent intraperitoneal (IP) cefazolin and ceftazidime. The pharmacokinetics (PK) of these agents combined have not been studied. This study was designed to determine the PK of combined IP cefazolin and ceftazidime in CAPD patients.

DESIGN

Prospective PK study in seven non-infected CAPD patients.

PROCEDURES

Patients had a peritoneal equilibration test (PET), then received one IP dose of cefazolin and ceftazidime (15 mg/kg each) co-administered over a 4-hour dwell, then performed three CAPD exchanges over the next 16 hours. Serum and dialysate samples collected over the 20-hour study period were assayed for drug concentrations by HPLC.

OUTCOME MEASURES

PK parameters.

STATISTICAL METHODS

Correlations were tested between PET and PK parameters using the Pearson-product correlation coefficient.

MAIN FINDINGS

Serum cefazolin and ceftazidime levels exceeded the minimum inhibitory concentrations for susceptible organisms (8 mg/L) throughout the 20 hour study period. Mean cefazolin and ceftazidime PK parameters included: bioavailability, 71% and 63%; elimination rate constant, 0.031 and 0.045 h -1 ; total clearance, 5.8 and 16.0 ml/min; peritoneal clearance, 1.6 and 3.9 ml/min; renal clearance, 2.3 and 3.9 ml/min, respectively. Predictive equations suggest that 1000 mg IP of cefazolin and of ceftazidime every 24 hours would produce average steady-state trough serum cefazolin and ceftazidime concentrations of 70 +/- 52 mg/L and 17 +/- 7 mg/L, respectively. There was no correlation between PET and PK parameters.

CONCLUSIONS

Co-administration did not adversely affect the PK of either agent. IP cefazolin and ceftazidime (15 mg/kg) produced adequate serum and dialysate concentrations in CAPD patients for 20 hours. PK predictions suggest that most patients would achieve adequate cefazolin and ceftazidime concentrations with 1000 mg IP once-daily. Anuric patients and those with significant residual renal function may require a more individualized approach.

Intraperitoneal cefazolin and ceftazidime effects on human peritoneal mesothelial cell release of cancer antigen-125

BACKGROUND

Intraperitoneal (IP) cefazolin and ceftazidime are recommended as empiric treatment for peritoneal dialysis (PD)-associated peritonitis. Human peritoneal mesothelial cells (HPMCs) may be affected by high IP cefazolin and ceftazidime concentrations. Peritoneal dialysate cancer antigen-125 (CA-125) appearance rate can be used to measure HPMC damage.

OBJECTIVE

To determine whether IP cefazolin and ceftazidime increase peritoneal CA-125 appearance rate.

METHODS

The study consisted of 2 phases. In phase I, no antibiotic was administered, and in phase II, patients received IP cefazolin and ceftazidime (15 mg/kg rounded to nearest 100 mg). Phase II occurred immediately after phase I. Each phase used a 4-hour dwell time with 2 L of dextrose 2.5% dialysate. Dialysate samples were collected at 0, 0.5, 1, 2, and 4 hours during each phase. Samples were assayed for CA-125, and CA-125 appearance rate was calculated.

RESULTS

Thirteen patients were recruited (7 men; aged 44.0 +/-16.0 y). The mean +/- SD (range) CA-125 dialysate concentration after phases I and II were 6.6 +/- 3.7 U/mL (2.3-15.0) and 6.4 +/-3.8 U/mL (1.6-13.8), respectively (p = 0.46). The CA-125 appearance rate after phases I and II were 51.9 +/- 31.3 U/min/1.73 m(2) (13.8-113.0) and 50.5 +/- 32.9 U/min/1.73 m(2) (11.0-104.0), respectively (p = 0.57). The slopes of the regression lines of CA-125 appearance rate were not significantly different between phases I and II.

CONCLUSIONS

These findings demonstrate that concurrently administered IP cefazolin and ceftazidime have no effect on HPMC release of CA-125 in non-infected PD patients.

Continuous peritoneal dialysis-associated peritonitis: a review and current concepts

The percentage of end-stage renal disease (ESRD) patients in the United States maintained on continuous peritoneal dialysis (CPD) therapy is decreasing. Complications from CPD therapy, including peritonitis, may be the reason for the decline. Improvements in CPD technology and a better understanding of the risk factors that predispose patients to the development of peritonitis have been responsible for a decline in the rate of peritonitis. Yet peritonitis remains a significant cause of patient morbidity and mortality and the overall outcome of peritonitis is not acceptable. Factors that have limited our ability to lessen the impact of peritonitis include a lack of data on dosing antibiotics in patients on continuous cycling peritoneal dialysis (CCPD) therapy, a lack of knowledge concerning the biology of bacterial biofilm, and the development of resistance to the current prophylactic antibiotic protocols. Further studies are needed concerning the optimal management of the peritoneal catheter and whether it is feasible to resume CPD therapy after catheter removal.

Management of peritonitis in children receiving chronic peritoneal dialysis

Bacterial peritonitis is a major threat to long-term peritoneal membrane function in pediatric patients receiving chronic peritoneal dialysis (CPD). This review summarizes the demographics, risk factors, and current recommendations regarding diagnostic procedures, management, and prevention of peritonitis in children. Albeit decreasing in incidence, bacterial peritonitis remains a major cause of technique failure in children with endstage renal disease receiving CPD. The use of standardized diagnostic procedures, efficacious antibacterial treatment, and objective response criteria are crucial in improving the outcome of this complication. Current guidelines recommend combining a first- and third-generation cephalosporin for empiric therapy in uncomplicated cases. The initial use of a glycopeptide/third-generation cephalosporin combination should be restricted to patients with risk factors for severe disease, as defined by clinical presentation, young age (<2 years), and recent infection with a methicillin resistant micro-organism. Several risk factors for primary or relapsing peritonitis have been identified, some of which are amenable to preventive measures. These relate to catheter design and implantation technique, connection methodology, early catheter removal in refractory or relapsing peritonitis, and eradication of Staphylococcus aureus from the catheter exit site and/or nasal reservoirs in patients and their caregivers.

Treatment of peritonitis in APD: pharmacokinetic principles

Clinicians treating peritoneal dialysis (PD)-associated peritonitis should be aware that continuous ambulatory PD (CAPD) and automated PD (APD) have different effects on the pharmacokinetics of antibiotics. Results from various APD and comparative CAPD pharmacokinetic studies are reviewed. In APD patients, antibiotic half-lives were shorter during the cycler exchanges. Antibiotic peritoneal clearance was greater in patients treated with APD than those treated with CAPD regimens. Antibiotic clearance depends upon residual renal function and dialysate flow rate. To ensure that maximal antibiotic bioavailability occurs with intermittent intraperitoneal (IP) dosing, it is recommended that the antibiotic-containing dialysate must dwell at least 4 hours to ensure an adequate antibiotic depot in the body. Knowledge of antibiotic disposition in PD patients will assist clinicians in appropriate IP antibiotic dose selection and prevention of dose-related adverse effects.

Infections in patients undergoing peritoneal dialysis

Considering experience acquired in the past years, it seems as though physicians have reached a plateau in the frequency of peritonitis. A peritonitis rate of 1 every 2 patient years may be acceptable. Further reduction of this peritonitis rate will require inordinately large efforts on all fronts. One will have to consider what are the acceptable costs and risks of peritonitis in patients on peritoneal dialysis. New developments in catheter technology, improved connections, better understanding of patient selection and training programs, improved diagnostic and therapeutic methods in the management of peritonitis, and understanding of the infectious and immune processes are eagerly awaited developments.

Cefazolin dialytic clearance by high-efficiency and high-flux hemodialyzers

Cefazolin dialytic clearance has not been determined in patients undergoing hemodialysis with high-efficiency or high-flux dialyzers. The objective of this study is to determine the pharmacokinetics and dialytic clearance of cefazolin and develop dosing strategies in these patients. Twenty-five uninfected subjects undergoing chronic thrice-weekly hemodialysis were administered a single dose of intravenous cefazolin (15 mg/kg) after their standard hemodialysis session. Fifteen subjects underwent hemodialysis with high-efficiency hemodialyzers, and 10 subjects underwent hemodialysis with high-flux hemodialyzers. Blood and urine samples were collected serially over the interdialytic period, during the next intradialytic period, and immediately after the next hemodialysis session. Serum and urine concentrations of cefazolin were determined by high-performance liquid chromatography. Differential equations describing a two-compartment model were fit to the cefazolin serum concentration-time data over the study period, and pharmacokinetic parameters were determined. Mean dialytic clearance values for cefazolin were significantly greater in the high-flux group compared with the high-efficiency group (30.9 +/- 6.52 versus 18.0 +/- 6.26 mL/min, respectively; P: < 0.05). Cefazolin reduction ratios were significantly greater (0.62 +/- 0.08 versus 0.50 +/- 0.07; P: < 0.005) in the high-flux group compared with the high-efficiency group and correlated well with equilibrated urea reduction. The pharmacokinetic model developed from patient data was used to simulate cefazolin serum concentration data for high-efficiency and high-flux dialyzers. Cefazolin doses of 15 or 20 mg/kg after each hemodialysis session maintained adequate serum concentrations throughout a 2- or 3-day interdialytic period regardless of hemodialyzer type.

Initial treatment of peritoneal dialysis peritonitis without vancomycin with a once-daily cefazolin-based regimen

To reduce the use of vancomycin, the current recommendations of the International Society of Peritoneal Dialysis (PD) for the initial treatment of peritonitis complicating PD are to administer intraperitoneal (IP) cefazolin or cephalothin in every PD fluid bag, together with once-daily gentamicin. In view of the inherent impracticalities of this regimen, we studied the efficacy of once-daily cefazolin (1.5 g) IP with gentamicin IP as initial treatment for primary (nonrecurrent) PD peritonitis. This regimen has been used in all episodes of peritonitis not associated with tunnel or exit-site infections or fluid leaks. Sixty-nine episodes in 61 patients were analyzed (44 patients, continuous ambulatory PD; 22 patients, automated PD; and 3 patients, hospital-based intermittent PD), of which 38 episodes (55%) were gram-positive infections, 6 episodes (9%) were gram-negative infections, and 18 episodes (26%) had negative culture results. Four patients died within 4 weeks of infection (none considered attributable to inadequate treatment of their peritonitis). Ten catheters (14.5%) required removal to clear the infection; 7 catheters were in patients with gram-negative infections. The relapse rate within 4 weeks of ceasing antibiotic therapy was 8.9%. Compared with the results of 40 episodes of peritonitis treated initially with our previous IP vancomycin and gentamicin regimen, successful treatment (no death, catheter removal, or recurrence) was achieved in 52 of 69 episodes in the cefazolin group (75.4%) versus 23 of 40 episodes in the vancomycin group (57.5%; P: = 0.058). In conclusion, once-daily IP cefazolin and gentamicin for the initial treatment of PD peritonitis is at least as effective as a vancomycin-based regimen and is well tolerated.

Pharmacokinetics of intermittent intravenous cefazolin and tobramycin in patients treated with automated peritoneal dialysis

There is increasing use of intermittent dosing of antibiotics to treat peritoneal dialysis (PD)-related peritonitis. The disposition of intravenous cefazolin and tobramycin was studied in automated PD (APD) patients. Ten patients were recruited and received a single intravenous dose of cefazolin (15 mg/kg) and tobramycin (0.6 mg/kg). Blood and dialysate samples were collected at the beginning, middle, and end of dwells 1 to 3 (on cycler), and at the end of dwells 4 to 5 (off cycler) for a 24-h period. Baseline and 24-h urine samples were collected. Pharmacokinetic parameters were calculated using a monoexponential model. Cefazolin and tobramycin half-lives were markedly different on cycler than off cycler (cefazolin on cycler : 10.67 +/- 4.66 h; cefazolin off cycler : 23.09 +/- 5.6 h; P = 0.001; tobramycin on cycler : 14.27 +/- 4.53 h; tobramycin off cycler : 68. 5 +/- 26.47 h; P < 0.001). Mean serum and dialysate concentrations were above minimum inhibitory concentrations of susceptible organisms throughout the 24-h period for both drugs with intravenous administration. A model was developed to examine serum and dialysate concentrations after intermittent intraperitoneal administration of 15 mg/kg cefazolin and 0.6 mg/kg tobramycin. Model-predicted intraperitoneal cefazolin provides adequate serum and dialysate concentrations for 24 h. Intermittent intraperitoneal tobramycin doses must be 1.5 mg/kg for one exchange during the first day and then given as 0.5 mg/kg thereafter. It is concluded that the current empiric dosing recommendations for PD-related peritonitis may be adequate for cefazolin (15 to 20 mg/kg); however, tobramycin doses must be changed to 1.5 mg/kg intraperitoneally on day 1, then to 0.5 mg/kg intraperitoneally thereafter in APD patients.