Peritoneal Catheters and Exit-Site Practices toward Optimum Peritoneal Access: 1998 Update

The peritoneal catheter is the PD patient's lifeline. Advances in catheter knowledge have made it possible to obtain access to the peritoneal cavity safely and to maintain access over an extended period of time. Catheter-related infections remain a major problem, solutions for which are being actively researched. Nevertheless, the successful outcome of a catheter is very much dependent on meticulous care and attention to detail. Adherence to the principles of catheter insertion and subsequent management and care remain the cornerstone of successful PD access. The guidelines provided in this publication represent a consensus view based on studies from the literature and opinions of experts in this field; it is hoped that implementation of these guidelines will improve catheter-related outcomes and, therefore, enhance patient care.

Prolonged Stability of Antimicrobial Activity in Peritoneal Dialysis Solutions

← Objective

To evaluate the stability of the antimicrobial chemical and bioactivity of gentamicin, vancomycin, and gentamicin and vancomycin in combination, and the stability of the bioactivity of ceftazidime, admixed in standard peritoneal dialysis solutions and then maintained over a 14-day period at room temperature or under refrigeration.

← Setting

Peritoneal dialysis center and microbiology laboratory at a military, teaching medical center.

← Measurements

Standard peritoneal dialysate bags admixed with gentamicin, vancomycin, gentamicin and vancomycin in combination, or ceftazidime were stored at either 4°C or 20°C for 14 days. Sequential aliquots were withdrawn and assayed for antibiotic activity by bioassay and, except for ceftazidime, immunoassay for chemical activity. The bioassay was performed using a standardized Kirby–Bauer disc method. Significance was determined by ANOVA and, where the effect size was significant at the p < 0.05 level, the application of the paired t-test or the Wilcoxon signed rank test to the difference in activity between the first and last samples.

← Results

Antibiotic concentration by immunoassay did not significantly deteriorate over 14 days for vancomycin or gentamicin when either room temperature or refrigerated samples were studied. By bioassay, gentamicin and ceftazidime, but not vancomycin, lost moderate but significant activity over 14 days when refrigerated bags were assayed (except for an insignificant decrement in gentamicin in the combined vancomycin and gentamicin bags). Bags stored at room temperature, in general, lost significant bioactivity over 14 days, but to levels where clinical efficacy would still be expected. The vancomycin bioassay performed on the combination bags demonstrated a remarkably enhanced bioactivity, presumably reflecting synergy with gentamicin.

← Conclusion

These data indicate that the study antibiotics admixed with peritoneal dialysis fluids retain stable chemical activity, whether refrigerated or kept at room temperature, for at least 14 days. A moderate decrement in bioactivity occurred for study antibiotics when stored either refrigerated or at room temperature over 14 days, although clinically significant levels were maintained. The clinical significance of a possible synergy between vancomycin and gentamicin is yet to be determined.

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.

Abdominal Catastrophe Revisited: The Risk and Outcome of Enteric Peritoneal Contamination

Objective

Peritonitis from a visceral source is associated with striking morbidity and mortality in patients treated with peritoneal dialysis (PD). Surgical intervention for both diagnosis and repair is definitive. However, because the antecedents of enteric injury leading to peritonitis are unpredictable, no preventive strategy has been proposed or adopted. The goal of this study was to examine risk factors influencing the occurrence and outcome of anatomically documented peritonitis of enteric origin.

Design

Retrospective chart and database review.

Setting

Peritoneal dialysis unit in tertiary-care referral hospital.

Patients

330 patients treated with PD for end-stage renal disease between 1988 and 2000.

Main Outcome Measures

Prevalence of peritonitis of anatomically documented enteric origin over two consecutive time periods within the study interval: period 1, from 1 January 1988 through 30 June 1996; period 2, from 1 July 1996 through 30 June 2000.

Results

At least 1 episode of peritonitis occurred in 202 of 330 patients during the entire study period of 12.5 years (600.74 patient-years of care). There were 543 episodes of peritonitis. Anatomically documented visceral injury caused bacterial peritonitis in 41 patients with a total of 63 discrete episodes, an incidence rate of 0.1048 per patient-year. Peritonitis-free survival was compared between the two periods using Kaplan–Meier analysis. The curve representing risk distribution for anatomically documented visceral peritonitis remained constant over the two periods, in contrast to improvements found in all other types of peritonitis, taken as a group ( p = 0.044). Logistic regression modeling showed that the only risk factor associated with development of anatomically documented visceral peritonitis was older age. There was no influence of race, sex, time on PD, and underlying disease etiology. 31 deaths were attributed to peritonitis during the study period. The mortality rate from enteric peritonitis due to visceral injury was 46.3% (19/41 cases), compared to 7.5% for all other peritonitis taken as a group (12/161 cases, p < 0.0001).

Conclusions

The experience at University Hospitals of Cleveland suggests that abdominal catastrophe occurs in approximately 10% of all patients treated with PD, and is associated with high mortality, which has not changed over time. Therefore, peritonitis due to spontaneous visceral injury presents a great diagnostic and therapeutic challenge. It is important to develop a research strategy to understand this devastating complication.

Pharmacokinetics of Intraperitoneal Cefazolin and Gentamicin in Empiric Therapy of Peritonitis in Continuous Ambulatory Peritoneal Dialysis Patients

Objective

The aim of this study was to measure and evaluate the appropriateness of the actual concentrations of serum and dialysate cefazolin and gentamicin in Thai continuous ambulatory peritoneal dialysis (CAPD) patients treated following the International Society for Peritoneal Dialysis (ISPD) 1996 recommendations for the empiric therapy of CAPD-related peritonitis.

Design

Prospective and descriptive study.

Setting

Institutional level of clinical care.

Patients

CAPD-related peritonitis patients were diagnosed by dialysate effluent white cell count of more than 100/mm3and polymorphonuclear leukocytes of at least 50%. There were 18 patients, all at least 15 years of age, entered; all completed the study.

Intervention

In accordance with the ISPD 1996 recommendations, the antibiotic regimen included continuous intraperitoneal (IP) cefazolin and once-daily IP amino-glycoside. Cefazolin was administered as loading and continuous maintenance doses of 500 and 125 mg/L dialysate, respectively. Gentamicin, 0.6 mg/kg body weight, was given IP once daily. Duration of treatment was 120 hours.

Main Outcome Measures

Serum and dialysate effluent samples of the 18 CAPD patients with peritonitis were measured and used for the synthesis of pharmacokinetic equations that could predict drug concentrations at any treatment time.

Results

Following administration according to the ISPD 1996 treatment recommendations, serum cefazolin reached levels higher than the recommended levels (8 mg/mL) at 3.3 minutes after drug administration, and persisted through the 5-day duration of the study. Dialysate cefazolin levels during the studied period also were persistently higher than the recommended values. The peak serum gentamicin levels were lower than the suggested values of 4 mg/mL, whereas the trough serum gentamicin levels were higher than the minimal toxic concentrations (2 mg/mL). Dialysate gentamicin levels were higher than therapeutic concentrations for only 4.75 hours in each day. It was difficult, using pharmacokinetic studies, to adjust the dosage regimen of gentamicin to achieve appropriately therapeutic levels in both serum and dialysate.

Conclusions

The ISPD 1996 recommended dosage of continuous IP cefazolin could be appropriate for the treatment of CAPD-related peritonitis. Once-daily IP gentamicin administration, however, has less therapeutic benefit and should be re-evaluated.

Pharmacokinetics of Intermittent Intraperitoneal Cefazolin in Continuous Ambulatory Peritoneal Dialysis Patients

Objective

To investigate the pharmacokinetic parameters of intermittent intraperitoneal (IP) cefazolin, and recommend a cefazolin dosing regimen in continuous ambulatory peritoneal dialysis (CAPD) patients.

Design

Prospective nonrandomized open study.

Setting

CAPD outpatient clinic in Albany, New York.

Patients

Seven volunteer CAPD patients without peritonitis. Three of the patients were nonanuric while 4 were anuric.

Interventions

Cefazolin (15 mg/kg total body weight) was given to each patient during the first peritoneal exchange. Blood and dialysate samples were collected at times 0, 0.5, 1, 2, 3, 6 (end of the first antibiotic-containing dwell), 24, and 48 hours after the administration of IP cefazolin. Urine samples were collected in nonanuric patients over the study period.

Results

The mean ± SD amount of cefazolin dose absorbed from the dialysate after the 6-hour dwell was 69.7% ± 8.0% of the administered dose. The cefazolin absorption rate constant from dialysate to serum was 0.21 ± 0.1 /hr (absorption half-life 3.5 ± 0.8 hr). The mean serum concentrations reached at 24 and 48 hours were 52.4 ± 3.7 mg/L and 30.3 ± 5.9 mg/L, respectively. The mean dialysate cefazolin concentrations reached at 24 and 48 hours were 15.1 ± 3.4 mg/L and 7.9 ± 1.4 mg/L, respectively. The cefazolin serum elimination rate constant was 0.02 ± 0.01 /hr (elimination half-life 31.5 ± 8.8 hr). The total cefazolin body clearance was 3.4 ± 0.6 mL/min. In the 3 nonanuric patients the mean renal clearance of cefazolin was 0.6 ± 0.4 mL/min. The peritoneal clearance of cefazolin was 1.0 ± 0.3 mL/min. The systemic volume of distribution of cefazolin was 0.2 ± 0.05 L/kg. No statistical difference was detected in pharmacokinetic parameters between anuric and nonanuric patients, although this may be due to the small number of patients in each group.

Conclusion

A single daily dose of cefazolin dosed at 15 mg/kg actual body weight in CAPD patients is effective in achieving serum concentration levels greater than the minimum inhibitory concentration for sensitive organisms over 48 hours, and dialysate concentration levels over 24 hours. Caution is warranted in extrapolation of dosing recommendations to patients who maintain a significant degree of residual renal function.

Ciprofloxacin and Cefazolin as a Combination for Empirical Initial Therapy of Peritoneal Dialysis-Related Peritonitis: Five-year Follow-up

The treatment of peritoneal dialysis (PD)-related peritonitis has been a matter of extensive investigation, frequently generating therapeutic trials. Several combinations of antibiotics have served as newer protocols and tended to be efficacious, comfortable, and cost-effective. According to the more recent recommendations from the International Society for Peritoneal Dialysis, the rationale for empirical initial therapy of clinically detected peritonitis in PD patients has been to follow the bacterial profile derived from cultured specimens of PD effluents.

The current study describes 5 year's experience with the use of a new antibiotic regimen for the treatment of peritonitis. We herein analyze the outcome of 95 episodes of peritonitis in 54 patients on either automated PD or continuous ambulatory PD at the dialysis unit of the Federal University of Rio de Janeiro. Peritoneal dialysis-related peritonitis was treated with the combination of oral ciprofloxacin and intraperitoneal cefazolin. The observed cure rate was 85.2% and the sensitivity test was observed to be positive for this combination of antibiotics in 88.9% of positive cultures. Of the 14 unsuccessful episodes, 7 were due to catheter colonization and the rest did not respond to the proposed therapy within 48 hours. These 7 cases were also related to peritoneal fluid cultures that were resistant to both ciprofloxacin and cefazolin.

From this study, we propose this combination of oral ciprofloxacin and intraperitoneal cefazolin as a first choice for empirical initial therapy of PD-related peritonitis, given its efficacy and low cost. However, in order to apply the most adequate cost-effective therapy, careful examination of the bacterial profile and sensitivities to antibiotics used in each unit is strongly recommended.

Continuous Ambulatory Peritoneal Dialysis in Patients with Hepatitis B Liver Disease

Objective

We hypothesized that patients with hepatitis B virus infection and cirrhosis are more susceptible to peritonitis as a complication of peritoneal dialysis (PD).

Methods

A retrospective study was carried out to compare peritonitis rates between cirrhotic and non-cirrhotic patients with hepatitis B virus infection.

Results

Between 1994 and 2004, 25 PD patients with hepatitis B cirrhosis and 36 patients with hepatitis B without cirrhosis were included for analysis. Mean follow-up duration was 52 months. Subjects with hepatitis B cirrhosis consisted of more males and had higher total body weight. No cirrhotic patients (20 of them being Child–Pugh class A, 2 class B, and 3 class C) had undergone portosystemic shunting or liver transplantation. Cirrhotic patients had slightly higher bilirubin concentration than the non-cirrhotic group (22 ± 50 vs 9 ± 4 μmol/L, p = 0.16). There was no difference in median peritonitis-free survival between cirrhotic and non-cirrhotic patients (40 vs 37 months, p = 0.64 by log-rank test). The average peritonitis rate was 1 episode every 19.2 patient-months in the cirrhotic group and 1 episode every 20.5 patient-months in the non-cirrhotic group. Time to first peritonitis did not differ between the two groups with respect to gram-negative organisms ( p = 0.88) or gram-positive organisms ( p = 0.52). Cirrhotic patients had more frequent Streptococcus species peritonitis, which accounted for 13% of all peritonitis episodes, as opposed to 2% among the non-cirrhotic patients ( p = 0.01). Overall treatment response rate and outcome did not differ between patients with and patients without cirrhosis.

Conclusions

Peritonitis-free survival of cirrhosis patients infected by hepatitis B virus compares favorably with that in patients without cirrhosis. The presence of liver cirrhosis does not appear to compromise PD outcome.

Risk Factors and Outcomes of Extended-Spectrum Beta-Lactamase-Producing E. Coli Peritonitis in Capd Patients

Objective

To determine the risk factors and outcomes of peritonitis caused by extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli in continuous ambulatory peritoneal dialysis (CAPD).

Patients and Methods

Episodes of E. coli CAPD peritonitis in our unit from October 1994 to August 2003 were reviewed. Demographic data, underlying medical conditions, recent use of gastric acid inhibitors (including H2 antagonist and proton pump inhibitor), recent antibiotic therapy, antibiotic regimen for peritonitis episodes, sensitivity test results of the E. coli isolated, and clinical outcomes were examined.

Results

Over a 10-year study period, 88 episodes of E. coli peritonitis were recorded; 11 of the 88 cases were caused by ESBL-producing E. coli. Recent use of cephalosporins and gastric acid inhibitor were associated with the development of ESBL-producing E. coli peritonitis. Compared with non-ESBL-producing E. coli peritonitis, more cases in the ESBL-producing E. coli group developed treatment failure (45.5% vs 13.0%, p = 0.02) and died of sepsis (27.3% vs 3.9%, p = 0.02). Peritoneal failure rate was higher in the ESBL-producing E. coli group, although the difference was not statistically significant (18.2% vs 3.9%, p = 0.12).

Conclusion

Peritonitis caused by ESBL-producing E. coli is associated with worse clinical outcomes. The use of cephalosporins and gastric acid inhibitors may contribute to its development. Further studies are warranted to investigate and determine the predisposing factors for ESBL-producing E. coli peritonitis.

Cefazolin plus Ceftazidime versus Imipenem / Cilastatin Monotherapy for Treatment of Capd Peritonitis — a Randomized Controlled Trial

Background

Peritonitis is a serious complication of peritoneal dialysis (PD). We studied the efficacy of imipenem / cilastatin monotherapy in the treatment of PD-related peritonitis.

Methods

We performed an open-label, randomized control study comparing imipenem / cilastatin monotherapy (treatment group) versus cefazolin plus ceftazidime (control group) in the treatment of PD peritonitis. The result was further compared to a historic group treated with cefazolin plus netilmycin. Outcome measures were primary response rate at day 10 and complete cure rate.

Results

We enrolled 51 patients in the treatment group, 51 in the control group, and identified 96 in the historic group. The primary response rate to the assigned antibiotics was 49.0%, 51.0%, and 49.0% for the treatment, control, and historic groups, respectively ( p = 0.97). The primary response rate allowing for change in antibiotic was 82.4%, 90.2%, and 82.3%, respectively, for the three groups ( p = 0.41). The complete cure rate was 72.5%, 80.4%, and 82.3%, respectively ( p = 0.60). Tenckhoff catheter removal was needed in 6 cases in the treatment group, 6 cases in the control group, and 13 cases in the historic group ( p = 0.90).

Conclusions

We concluded that monotherapy of imipenem / cilastatin has similar efficacy compared to the two standard regimens of cefazolin plus ceftazidime or netilmycin in the treatment of PD peritonitis.

Viridans streptococcus peritonitis in peritoneal dialysis: clinical characteristics and comparison with concurrent polymicrobial infection

Background

The clinical course of Viridans streptococci (VS) peritonitis in patients undergoing peritoneal dialysis (PD) is rarely reported. This study examined the association of clinical factors with VS peritonitis.

Methods

We retrospectively reviewed clinical data from patients with VS peritonitis from March 1990 to February 2016 in a PD center in Taiwan and evaluated clinical profiles and treatment outcomes.

Results

A total of 109 episodes of VS peritonitis in 71 patients identified. Among these patients, 57 had mono-VS peritonitis and 14 had concurrent polymicrobial infections. The median time interval from PD initiation to the first VS peritonitis episode was 18 months (range, 0.6–144 months). Among clinical outcomes, most VS peritonitis episodes were completely cured regardless of a history of peritonitis. All episodes with catheter removal occurred in those without a history of recent antibiotic use.

Conclusion

VS peritonitis in patients undergoing PD typically has favorable treatment outcomes. Antibiotic therapy should be started promptly.

Antibiogram Development for an Outpatient Dialysis Center

Infection causes significant morbidity and mortality in end-stage renal disease patients. Despite recommendations to the contrary, vancomycin is often used empirically. Antibiograms may aid in the choice of empiric antibiotic therapy. We developed an antibiogram and determined the susceptibility of various microorganisms to cefazolin, gentamicin, and vancomycin. Retrospective review of culture results and susceptibility data from a 21-month time period were used to determine microorganism frequency of identification and antimicrobial sensitivity. A total of 362 microorganisms were identified and 285 cultures performed in 171 patients (144 hemodialysis; 27 peritoneal dialysis). Predominant organisms were coagulase-negative staphylococci (39.8%) and Staphylococcus aureus (24.6%). Gram-positive organisms accounted for 73.5% of isolates. Methicillin-resistant S. aureus and vancomycin-resistant Enterococcus were identified 3.8% and 2.3% of time, respectively. Gram-positive and negative microorganisms were frequently susceptible to cefazolin and gentamicin. Antibiogram interpretation indicates that cefazolin alone or in combination with gentamicin may be appropriate empiric antibiotic therapy in our outpatient dialysis center.

Peritonitis before Peritoneal Dialysis Training: Analysis of Causative Organisms, Clinical Outcomes, Risk Factors, and Long-Term Consequences

BACKGROUND AND OBJECTIVES

Peritonitis before peritoneal dialysis (PD) training (pretraining peritonitis [PTP]) is an uncommon event. The study aim was to examine the causative organisms, clinical outcomes, risk factors, and long-term consequences of PTP.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

In this single-center, retrospective, observational study involving all incident patients on PD who developed PTP between 1998 and 2012, we examined the causative organisms, primary response rate, complete cure rate, risk factors, and associations of PTP with peritoneal equilibration test (PET) and patient survival. For each patient in the PTP group, the patients who underwent catheter insertion immediately before and after the index case were identified as controls.

RESULTS

Among 1252 incident patients on PD, 52 (4.2%) patients developed PTP, and 104 patients were identified as controls. The two groups were similar in age, sex distribution, comorbidities, and residual renal function, but the PTP group had significantly lower hemoglobin and serum albumin. Patients were followed up for a median of 37.5 months (interquartile range [IQR], 16.3-62.2 months). The most common causative organisms of PTP were Staphylococcus aureus (30.8%) and polymicrobial (21.2%); 25% had negative growth. The primary response and complete cure rates were 82.7% and 78.8%, respectively. In the PTP group, 7.7% of patients died, 9.6% of patients required catheter removal, and PD training was significantly delayed (median =42.0; IQR, 26.0-65.8 days versus 27.5; IQR, 23.0-35.0 days; P=0.01). Multivariate logistic regression analysis showed that serum albumin was the only predictor of PTP (adjusted odds ratio, 0.89 per 1-g/dl increase; 95% confidence interval, 0.82 to 0.97). There were no differences in PET results and dialysis adequacy (measured around 1 month after PD training). The PTP group had significantly worse patient survival (median =41.2; IQR, 21.8-60.5 months versus 55.8; IQR, 40.4-71.2 months; P=0.02). Technique failure occurred in 11.5% and 10.6% of patients in the PTP and control groups, respectively.

CONCLUSIONS

S. aureus is the most common causative organism of PTP. Nutritional interventions in patients who are hypoalbuminemic before catheter insertion deserve additional study.

Newer antibiotics for the treatment of peritoneal dialysis-related peritonitis

Peritonitis is a debilitating infectious complication of peritoneal dialysis (PD). Drug-resistant bacterial peritonitis typically has a lower response rate to antibiotics. In the past 15 years, newer antibiotics with activities against drug-resistant Gram-positive bacteria have been developed. In most circumstances, peritonitis due to methicillin-resistant staphylococci responds to vancomycin. If vancomycin cannot be used due to allergy and/or non-susceptibility, there is increasing evidence that linezolid and daptomycin are the drugs of choice. It is reasonable to start linezolid orally or intravenously, but subsequent dose reduction may be necessary in case of myelosuppression. Daptomycin can be given intravenously or intraperitoneally and has excellent anti-biofilm activity. Other treatment options for drug-resistant Gram-positive bacterial peritonitis include teicoplanin, tigecycline and quinupristin/dalfopristin. Teicoplanin is not available in some countries (e.g. the USA). Tigecycline can only be given intravenously. Quinupristin/dalfopristin is ineffective against Enterococcus faecalis and there is only low-quality evidence to support its efficacy in the treatment of peritonitis. Effective newer antibiotics against drug-resistant Gram-negative bacteria are lacking. Polymyxins can be considered, but evidence on its efficacy is limited. In this review, we will discuss the potential use of newer antibiotics in the treatment of drug-resistant bacterial peritonitis in PD patients.

Efficacy of antibiotic therapy for peritoneal dialysis-associated peritonitis: a proportional meta-analysis

Background

The choice of antimicrobials for initial treatment of peritoneal dialysis (PD)-related peritonitis is crucial for a favorable outcome. There is no consensus about the best therapy; few prospective controlled studies have been published, and the only published systematic reviews did not report superiority of any class of antimicrobials. The objective of this review was to analyze the results of PD peritonitis treatment in adult patients by employing a new methodology, the proportional meta-analysis.

Methods

A review of the literature was conducted. There was no language restriction. Studies were obtained from MEDLINE, EMBASE, and LILACS. The inclusion criteria were: (a) case series and RCTs with the number of reported patients in each study greater than five, (b) use of any antibiotic therapy for initial treatment (e.g., cefazolin plus gentamicin or vancomycin plus gentamicin), for Gram-positive (e.g., vancomycin or a first generation cephalosporin), or for Gram-negative rods (e.g., gentamicin, ceftazidime, and fluoroquinolone), (c) patients with PD-related peritonitis, and (d) studies specifying the rates of resolution. A proportional meta-analysis was performed on outcomes using a random-effects model, and the pooled resolution rates were calculated.

Results

A total of 64 studies (32 for initial treatment and negative culture, 28 reporting treatment for Gram-positive rods and 24 reporting treatment for Gram-negative rods) and 21 RCTs met all inclusion criteria (14 for initial treatment and negative culture, 8 reporting treatment for Gram-positive rods and 8 reporting treatment for Gram-negative rods). The pooled resolution rate of ceftazidime plus glycopeptide as initial treatment (pooled proportion = 86% [95% CI 0.82–0.89]) was significantly higher than first generation cephalosporin plus aminoglycosides (pooled proportion = 66% [95% CI 0.57–0.75]) and significantly higher than glycopeptides plus aminoglycosides (pooled proportion = 75% [95% CI 0.69–0.80]. Other comparisons of regimens used for either initial treatment, treatment for Gram-positive rods or Gram-negative rods did not show statistically significant differences.

Conclusion

We showed that the association of a glycopeptide plus ceftazidime is superior to other regimens for initial treatment of PD peritonitis. This result should be carefully analyzed and does not exclude the necessity of monitoring the local microbiologic profile in each dialysis center to choice the initial therapeutic protocol.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2334-14-445) contains supplementary material, which is available to authorized users.

Outcomes of chronic dialysis in Korean children with respect to survival rates and causes of death

Purpose

Adult Korean patients on chronic dialysis have a 9-year survival rate of 50%, with cardiovascular problems being the most significant cause of death. The 2011 annual report of the North American Pediatric Renal Trials and Collaborative Studies group reported 3-year survival rates of 93.4% and relatively poorer survival in younger patients.

Methods

In this study, we have reviewed data from Korean Pediatric Chronic Kidney Disease Registry from 2002 to 2010 to assess survival rates and causes of death in Korean children on chronic dialysis.

Results

The overall estimated patient survival rates were 98.4%, 94.4%, and 92.1% at 1, 3, and 5 years, respectively. No significant difference was observed in survival rates between patients on peritoneal dialysis and those on hemodialysis. Patients for whom dialysis was initiated before 2 years of age (n=40) had significantly lower survival rates than those for whom dialysis was initiated at 6-11 years of age (n=140). In all, 26 patients had died; the mortality rate was 19.9 per 1,000 patient years. The most common causes of death were infections and comorbidities such as malignancy and central nervous system (CNS) or liver diseases.

Conclusion

The outcomes observed in this study were better than those observed in adults and comparable to those observed in pediatric studies in other countries. To improve the outcomes of children on chronic dialysis, it is necessary to prevent dialysis-related complications such as infection, congestive heart failure, or CNS hemorrhage and best control treatable comorbidities.

Escherichia coli Peritonitis in peritoneal dialysis: the prevalence, antibiotic resistance and clinical outcomes in a South China dialysis center

INTRODUCTION

Escherichia coli (E. coli) peritonitis is a frequent, serious complication of peritoneal dialysis (PD). The extended-spectrum β-lactamase (ESBL)-producing E. coli peritonitis is associated with poorer prognosis and its incidence has been on continuous increase during the last decades. However, the clinical course and outcomes of E. coli peritonitis remain largely unclear.

METHODS

All of the E. coli peritonitis episodes that occurred in our dialysis unit from 2006 to 2011 were reviewed. The polymicrobial episodes were excluded.

RESULTS

In total, ninety episodes of monomicrobial E. coli peritonitis occurred in 68 individuals, corresponding to a rate of 0.027 episodes per patient-year. E. coli was the leading cause (59.2%) of monomicrobial gram-negative peritonitis. ESBL-producing strains accounted for 35.5% of E. coli peritonitis. The complete cure rate and treatment failure rate of E. coli peritonitis were 77.8% and 10.0% respectively. Patients with preceding peritonitis had a higher risk of ESBL production as compared to those without peritonitis history [odds ratio (OR): 5.286; 95% confidence interval (CI): 2.018 - 13.843; p = 0.001]. The risk of treatment failure was significantly increased when the patient had a baseline score of Charlson Comorbidity Index (CCI) above 3 (OR: 6.155; 95% CI: 1.198 - 31.612; p = 0.03), or had diabetes mellitus (OR: 8.457; 95% CI: 1.838 - 38.91; p = 0.006), or hypoalbuminemia (≤ 30g/l) on admission (OR: 13.714; 95% CI: 1.602 - 117.428; p = 0.01). Prolonging the treatment course from 2 to 3 weeks or more reduced the risk of relapse and repeat significantly (p < 0.05).

CONCLUSIONS

E. coli peritonitis remains a common complication of PD. The clinical outcomes of E. coli peritonitis are relatively favorable despite the high ESBL rate. A history of peritonitis is associated with increased risk for ESBL development. The severity of baseline comorbidities, the presence of diabetes mellitus and hypoalbuminemia at admission are associated with poor outcomes.

Predictors of residual renal function decline in patients undergoing continuous ambulatory peritoneal dialysis

BACKGROUND

Residual renal function (RRF) is an important prognostic indicator in continuous ambulatory peritoneal dialysis (CAPD) patients. We determined the predictors of RRF loss in a cohort of incident CAPD patients.

METHODS

We reviewed the record of 645 incident CAPD patients. RRF loss is represented by the slope of decline of residual glomerular filtration rate (GFR) as well as the time to anuria.

RESULTS

The average rate of residual GFR decline was -0.083 ± 0.094 mL/min/month. The rate of residual GFR decline was faster with a higher proteinuria (r = -0.506, p < 0.0001) and baseline residual GFR (r = -0.560, p < 0.0001). Multivariate analysis showed that proteinuria, baseline residual GFR, and the use of diuretics were independent predictors of residual GFR decline. Cox proportional hazard model showed that proteinuria, glucose exposure, and the number of peritonitis episodes were independent predictors of progression to anuria, while a higher baseline GFR was protective. Each 1 g/day of proteinuria is associated with a 13.2% increase in the risk of progressing to anuria, each 10 g/day higher glucose exposure is associated with a 2.5% increase in risk, while each peritonitis episode confers a 3.8% increase in risk.

CONCLUSIONS

Our study shows that factors predicting the loss of residual solute clearance and urine output are different. Proteinuria, baseline residual GFR, and the use of diuretics are independently related to the rate of RRF decline in CAPD patients, while proteinuria, glucose exposure, and the number of peritonitis episodes are independent predictors for the development of anuria. The role of anti-proteinuric therapy and measures to prevent peritonitis episodes in the preservation of RRF should be tested in future studies.

Infectious complications in dialysis--epidemiology and outcomes

This Review focuses on the changing epidemiology of infections among patients with end-stage renal disease who are undergoing dialysis. In particular, bloodstream infections related to vascular access in patients undergoing hemodialysis, and peritonitis in patients undergoing peritoneal dialysis, are highlighted. Gram-positive (staphylococcal and enterococcal) bloodstream infections and Gram-negative peritonitis (especially extended-spectrum β-lactamase-producing organisms) contribute substantially to excess health-care use owing to infection caused by dialysis access. Although the management of peritoneal-dialysis-related peritonitis has been hampered by a dearth of randomized, controlled studies, epidemiological data have provided useful information. To overcome the problem of differing methods used to monitor infections within various dialysis centers, uniform reporting systems for vascular-access-related infection and peritoneal-dialysis-related peritonitis, as recommended by the Centers for Disease Control and Prevention and the International Society for Peritoneal Dialysis, respectively, are discussed. Infections unrelated to the port of entry for dialysis are also examined, namely hepatitis and respiratory infection. To address the disease burden, we examine the infection-related mortality as well as the implications for subsequent cardiovascular mortality.

A comparative study of sterility levels in continuous ambulatory peritoneal dialysis system

INTRODUCTION

Peritonitis remains a serious risk associated with continuous ambulatory peritoneal dialysis (CAPD), although better patient education programs and such technological advances as improved automated connecting devices have greatly decreased its incidence over the past 20 years. The automated devices have a good resistance to contamination, but they rely on an external electrical power source and are not easily portable. There has, therefore, been a need for a highly sterile nonelectric manual connecting device to complement the automated devices already in use. Such a manual device has recently been developed. We compared the level of sterility after touch contamination in this new device with levels in 2 other connecting devices: a conventional device with a manual cap (JMS Co. Ltd., Hiroshima, Japan), and a powered total containment device (JMS Co. Ltd.).

METHOD

Five bacteria frequently causing CAPD-related peritonitis (Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans) were separately applied to the tip of each connecting device, and peritoneal washing fluid was injected as in a routine exchange. We used a membrane filter method to determine whether the route had been contaminated by the washing fluid.

RESULTS

In the conventional device with a manual cap, 3 to 4 colony-forming units (CFUs) of S. aureus were detected in 2 of 10 drainage samples, 8 CFUs of E. coli in 1 of 10 drainage samples, and 1 CFU of E. coli in the injection fluid. In contrast, no contamination was detected in the automated connecting device or the new manual cap device.

CONCLUSION

This study confirmed that the new device has a risk of touch contamination lower than that of the conventional manual cap device and equal to that of the automated device. Being easily portable and not reliant on an external power source, the new device should be useful in various situations.

Repeat peritonitis in peritoneal dialysis: retrospective review of 181 consecutive cases

BACKGROUND AND OBJECTIVES

The clinical behavior of repeat-peritonitis episodes, defined as peritonitis with the same organism occurring more than 4 weeks after completion of therapy for a prior episode, is poorly understood.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We compared outcomes of 181 episodes of repeat peritonitis from 1995 to 2009 (Repeat Group) with 91 episodes of relapsing peritonitis (Relapsing Group) and 125 episodes of peritonitis preceded 4 weeks or longer by another episode with a different organism (Control Group).

RESULTS

In Repeat Group, 24% were due to Staphylococcus aureus, as compared with 5.5% in Relapsing Group and 15% in Control Group. The majority of the organisms causing relapsing peritonitis were Gram negative (62%), whereas the majority of that in Repeat Group were Gram positive (56%). Repeat Group had a lower complete-cure rate (70.7% versus 54.9%) than Relapsing Group, but rates of primary response, catheter removal, and mortality were similar. Repeat Group had a higher primary response rate (89.0% versus 73.6%) and a lower rate of catheter removal (6.1% versus 15.2%) than Control Group, whereas the complete-cure rate and mortality were similar. Repeat Group had a higher risk of developing relapsing (14.3% versus 2.2%) and repeat peritonitis (26.1% versus 5.4%) than Control Group, whereas the risk of recurrent peritonitis was similar.

CONCLUSIONS

Repeat peritonitis is a distinct clinical entity. Although repeat-peritonitis episodes generally have a satisfactory response to antibiotic, they have a substantial risk of developing further relapsing or repeat peritonitis.

Correlation between hearing loss and peritonitis frequency and administration of ototoxic intraperitoneal antibiotics in patients with CAPD

AIM

Aminoglycosides have been used in the treatment of CAPD peritonitis despite their potential risk for ototoxicity. The ototoxicity risk of intraperitoneally administered aminoglycosides has been investigated by a number of studies. However, their results are somewhat conflicting. The aim of the present study was to examine the frequency of hearing loss and the correlation between the repeated doses of aminoglycosides and hearing loss in CAPD peritonitis therapy.

METHODS

Hearing functions of the CAPD patients who had developed peritonitis and had been treated with various antibiotics including aminoglycosides were compared with those CAPD patients who had never developed peritonitis. Threshold values for hearing were determined through "pure tone audiometry" measurements.

RESULTS

Hearing threshold levels of the patients with history of peritonitis were found to be significantly higher in both lower [pure tone averages - 1 (PTA-1)] and higher [pure tone averages - 2 (PTA-2)] frequencies, when compared to the ones with no history of peritonitis (p values were 0.001 and 0.007, respectively).

CONCLUSION

The present study showed that intraperitoneal aminoglycoside administration in CAPD patients is associated with the development of hearing loss. The severity of hearing loss may range from mild hearing loss to profound deafness. A remarkable correlation exists between the severity of the hearing loss and the repeated and total aminoglycoside dose received.

Persistent symptomatic intra-abdominal collection after catheter removal for PD-related peritonitis

BACKGROUND

Peritoneal dialysis (PD) patients with severe peritonitis require catheter removal. It is often assumed that this approach, together with antibiotics, would eradicate the infection; however, some patients continue to have problems despite catheter removal.

METHOD

We reviewed 30 consecutive PD patients in our center from 1997 to 2008 with recurrent loculated peritoneal collection after catheter removal for severe peritonitis.

RESULTS

Of the 1928 episodes of peritonitis that occurred in 702 patients during the study period, 11.1% required catheter removal and 1.6% developed recurrent peritoneal collection that required percutaneous drainage. Median time to diagnosis of intra-abdominal collection was 12 days after catheter removal (interquartile range 7 - 61 days). In 25 patients (83.3%), aspirate of the abdominal collection was culture negative. In 17 patients (56.7%), the abdominal collection was recurrent and required repeated percutaneous aspiration. Only 3 patients had successful reinsertion of the peritoneal catheter but all had reduced small solute clearance after returning to PD.

CONCLUSION

A small but not negligible proportion of patients with PD-related peritonitis develop recurrent intra-abdominal collection that requires percutaneous drainage after catheter removal. The chance of a successful return to PD is very low in this group of patients. Direct conversion to long-term hemodialysis may avoid unnecessary attempts at peritoneal catheter reinsertion.

Detecting bacterial growth in continuous ambulatory peritoneal dialysis effluent using two culture methods

BACKGROUND/AIMS

The aim of this study was to evaluate the peritonitis-causing bacteria detected in peritoneal fluid using a blood culture bottle in patients undergoing continuous ambulatory peritoneal dialysis (CAPD).

METHODS

One-hundred and eleven dialysates from 43 patients suspected of peritonitis related to CAPD were retrospectively evaluated between May 2000 and February 2008. In all cases, 5 to 10 mL of dialysate was inoculated into a pair of BacT/Alert blood culture bottles, and 50 mL of centrifuged dialysate was simultaneously inoculated into a solid culture media for conventional culture. The results were compared to those of the conventional culture method. Isolated microorganisms were compared between the two methods.

RESULTS

The blood culture method was positive in 78.6% (88 / 112) of dialysate specimens and the conventional culture method in 50% (56 / 112, p < 0.001).

CONCLUSIONS

The blood culture method using the BacT/Alert system is useful for culturing dialysates and improves the positive culture rate in patients with suspected peritonitis compared to the conventional culture method.

Dialysis-associated peritonitis in children

Peritonitis remains a frequent complication of peritoneal dialysis in children and is the most common reason for technique failure. The microbiology is characterized by a predominance of Gram-positive organisms, with fungi responsible for less than 5% of episodes. Data collected by the International Pediatric Peritonitis Registry have revealed a worldwide variation in the bacterial etiology of peritonitis, as well as in the rate of culture-negative peritonitis. Risk factors for infection include young age, the absence of prophylactic antibiotics at catheter placement, spiking of dialysis bags, and the presence of a catheter exit-site or tunnel infection. Clinical symptoms at presentation are somewhat organism specific and can be objectively assessed with a Disease Severity Score. Whereas recommendations for empiric antibiotic therapy in children have been published by the International Society of Peritoneal Dialysis, epidemiologic data and antibiotic susceptibility data suggest that it may be desirable to take the patient- and center-specific history of microorganisms and their sensitivity patterns into account when prescribing initial therapy. The vast majority of patients are treated successfully and continue peritoneal dialysis, with the poorest outcome noted in patients with peritonitis secondary to Gram-negative organisms or fungi and in those with a relapsing infection.

The role of virulence factors in the outcome of staphylococcal peritonitis in CAPD patients

Background

Peritonitis continues to be the most frequent cause of peritoneal dialysis (PD) failure, with an important impact on patient mortality. Gram-positive cocci such as Staphylococcus epidermidis, other coagulase-negative staphylococci (CoNS), and Staphylococcus aureus are the most frequent etiological agents of PD-associated peritonitis worldwide. The objective of the present study was to compare peritonitis caused by S. aureus and CoNS and to evaluate the factors influencing outcome.

Methods

Records of 86 new episodes of staphylococcal peritonitis that occurred between 1996 and 2000 in the Dialysis unit of a single university hospital were studied (35 due to S. aureus, 24 to S. epidermidis and 27 to other CoNS). The production of slime, lipase, lecithinase, nuclease (DNAse), thermonuclease (TNAse), α- and β-hemolysin, enterotoxins (SEA, SEB, SEC, SED) and toxic shock syndrome toxin-1 (TSST-1) was studied in S. aureus and CoNS. Antimicrobial susceptibility was evaluated based on the minimal inhibitory concentration determined by the E-test. Outcome predictors were evaluated by two logistic regression models.

Results

The oxacillin susceptibility rate was 85.7% for S. aureus, 41.6% for S. epidermidis, and 51.8% for other CoNS (p = 0.001). Production of toxins and enzymes, except for enterotoxin A and α-hemolysin, was associated with S. aureus episodes (p < 0.001), whereas slime production was positive in 23.5% of CoNS and 8.6% of S. aureus strains (p = 0.0047). The first model did not include enzymes and toxins due to their association with S. aureus. The odds of resolution were 9.5 times higher for S. epidermidis than for S. aureus (p = 0.02) episodes, and were similar for S. epidermidis and other CoNS (p = 0.8). The resolution odds were 68 times higher for non-slime producers (p = 0.001) and were not influenced by oxacillin resistance among vancomycin-treated cases (p = 0.89). In the second model, the resolution rate was similar for S. aureus and S. epidermidis (p = 0.70), and slime (p = 0.001) and α-hemolysin (p = 0.04) production were independent predictors of non-resolution.

Conclusion

Bacterial species and virulence factors rather than antibiotic resistance influence the outcome of staphylococcal peritonitis.

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

BACKGROUND

The study aim was to examine the frequency, predictors, treatment, and clinical outcomes of peritoneal dialysis-associated polymicrobial peritonitis.

STUDY DESIGN

Observational cohort study using ANZDATA (The Australia and New Zealand Dialysis and Transplant Registry) data.

SETTING & PARTICIPANTS

All Australian peritoneal dialysis patients between October 2003 and December 2006.

PREDICTORS

Age, sex, race, body mass index, baseline renal function, late referral, kidney disease, smoking status, comorbidity, peritoneal permeability, center, state, organisms, and antibiotic regimen.

OUTCOMES & MEASUREMENTS

Polymicrobial peritonitis occurrence, relapse, hospitalization, catheter removal, hemodialysis transfer, and death.

RESULTS

359 episodes of polymicrobial peritonitis occurred in 324 individuals, representing 10% of all peritonitis episodes during 6,002 patient-years. The organisms isolated included mixed Gram-positive and Gram-negative organisms (41%), pure Gram-negative organisms (22%), pure Gram-positive organisms (25%), and mixed bacteria and fungi (13%). There were no significant independent predictors of polymicrobial peritonitis except for the presence of chronic lung disease. Compared with single-organism infections, polymicrobial peritonitis was associated with higher rates of hospitalization (83% vs 68%; P < 0.001), catheter removal (43% vs 19%; P < 0.001), permanent hemodialysis transfer (38% vs 15%; P < 0.001), and death (4% vs 2%; P = 0.03). Isolation of fungus or Gram-negative bacteria was the primary predictor of adverse clinical outcomes. Pure Gram-positive peritonitis had the best clinical outcomes. Patients who had their catheters removed >1 week after polymicrobial peritonitis onset were significantly more likely to be permanently transferred to hemodialysis therapy than those who had earlier catheter removal (92% vs 81%; P = 0.05).

LIMITATIONS

Limited covariate adjustment. Residual confounding and coding bias could not be excluded.

CONCLUSIONS

Polymicrobial peritonitis can be treated successfully using antibiotics alone without catheter removal in most cases, particularly when only Gram-positive organisms are isolated. Isolation of Gram-negative bacteria (with or without Gram-positive bacteria) or fungi carries a worse prognosis and generally should be treated with early catheter removal and appropriate antimicrobial therapy.

Recurrent and relapsing peritonitis: causative organisms and response to treatment

BACKGROUND

The clinical behavior and optimal treatment of relapsing and recurrent peritonitis episodes in patients undergoing long-term peritoneal dialysis are poorly understood.

STUDY DESIGN

Retrospective study over 14 years.

SETTING & PARTICIPANTS

University dialysis unit; 157 relapsing episodes (same organism or culture-negative episode occurring within 4 weeks of completion of therapy for a prior episode), 125 recurrent episodes (different organism, occurs within 4 weeks of completion of therapy for a prior episode), and 764 control episodes (first peritonitis episode without relapse or recurrence).

PREDICTORS

Exit-site infection, empirical antibiotics.

OUTCOME MEASURES

Primary response (resolution of abdominal pain, clearing of dialysate, and peritoneal dialysis effluent neutrophil count < 100 cells/mL after 10 days of antibiotic therapy), complete cure (resolution by using antibiotics without relapse/recurrence), catheter removal (for any cause while on antibiotic therapy), and mortality.

RESULTS

Compared with the control group, more relapsing episodes were caused by Pseudomonas species (16.6% versus 9.4%) and were culture negative (29.9% versus 16.4%); recurrent infections commonly were caused by Enterococcus species (3.2% versus 1.2%) or other Gram-negative organisms (27.2% versus 11.1%) or had mixed bacterial growth (17.6% versus 12.7%). There were significant differences in primary response, complete cure, and mortality rates among groups (P < 0.001 for all comparisons). Compared with the control and relapsing groups, post hoc analysis showed that the recurrent group had a significantly lower primary response rate (86.4%, 88.5%, and 71.2%, respectively), lower complete cure rate (72.3%, 62.4%, and 42.4%, respectively), and higher mortality rate (7.7%, 7.0%, and 20.8%, respectively).

LIMITATIONS

Retrospective analysis.

CONCLUSION

Relapsing and recurrent peritonitis episodes are caused by different spectra of bacteria and probably represent 2 distinct clinical entities. Recurrent peritonitis episodes had a worse prognosis than relapsing ones.

Antibiotics induce apoptosis of human peritoneal mesothelial cells

The peritoneal mesothelial cell is a critical component of the peritoneal membrane. The intraperitoneal use of several antibiotics to treat bacterial peritonitis is current clinical practice. Our previous study showed that cephalothin (CPL) and cefotaxime (CFT) have cytotoxic effects on human peritoneal mesothelial cells (HPMC), however, the exact mechanism of cytotoxicity has not been elucidated. In the present study, flow cytometry, TdT-mediated dUTP nick-end labelling (TUNEL) staining and electron microscopy were used to detect the apoptosis of HPMCs. Immunofluorescent staining was used to evaluate the cytochrome c distribution pattern. Western blotting was used to assess apoptotic signalling proteins. We found that CPL (0.5 mg/mL) and CFT (1 mg/mL) induced apoptosis of HPMCs, whereas cefazolin (0.5 mg/mL) and ceftriaxone (0.5 mg/mL) failed to induce apoptosis of HPMCs. While the DNA content of CFT- or CPL-treated cells was reduced, as determined by flow cytometry, cefazolin and ceftriaxone had no such effect. The CFT- or CPL-treated cells displayed the features of apoptosis both under the electron microscope and by using TUNEL staining. However, cefazolin and ceftriaxone produced the same result as the medium controls. Furthermore, CFT and CPL increased the expression of Bax and p53, and caused the translocation of cytochrome c from the mitochondria to the cytoplasm. The HPMC treated by CFT but not by CPL induced the cleavage of procaspase-3 to form active caspase-3. In conclusion, cefotaxime and cephalothin induce apoptosis of HPMCs in vitro. Signal transduction may be through the mitochondrial pathway.

The evidence base for the efficacy of antibiotic prophylaxis in dental practice

INTRODUCTION

People with various medical conditions and devices are suggested candidates for receiving antibiotic prophylaxis before undergoing dental procedures. This practice is controversial, however, owing to the lack of proof of efficacy. The authors conducted a qualitative, systematic review to determine the level of evidence for this practice and whether antibiotic prophylaxis prevents distant site infections in these patients.

METHODS

The authors selected eight groups of patients with specific medical conditions and devices who often are given antibiotic prophylaxis before undergoing invasive dental procedures. The conditions and devices were cardiac-native heart valve disease, prosthetic heart valves and pacemakers; hip, knee and shoulder prosthetic joints; renal dialysis shunts; cerebrospinal fluid shunts; vascular grafts; immunosuppression secondary to cancer and cancer chemotherapy; systemic lupus erythematosus; and insulin-dependent (type 1) diabetes mellitus. The authors thoroughly searched the literature for the years 1966 through 2005 for references indicating some level of support for this practice and graded each publication on the basis of level of evidence.

RESULTS

The authors found formal recommendations in favor of antibiotic prophylaxis for only three of the eight medical conditions: native heart disease, prosthetic heart valves and prosthetic joints. They found no prospective randomized clinical trials and only one clinical study of antibiotic prophylaxis. Only one systematic review and two case series provided weak, if any, support for antibiotic prophylaxis in patients with cardiac conditions. The authors found little or no evidence to support this practice or to demonstrate that it prevents distant site infections for any of these eight groups of patients.

CONCLUSIONS

No definitive, scientific basis exists for the use of prophylactic antibiotics before dental procedures for these eight groups of patients.

Continuous ambulatory peritoneal dialysis peritonitis: broth inoculation culture versus water lysis method

BACKGROUND/AIM

In the setting of empiric antibiotic treatment of peritoneal-dialysis-related peritonitis complications, the speed with which a bacteriological diagnosis can be achieved is of importance. We compare the clinical performance of two culture methods to diagnose the causative microorganisms as suggested by the International Society for Peritoneal Dialysis and the United Kingdom Health Protection Agency.

METHODS

We prospectively evaluated microbiological cultures of peritoneal fluid samples by the direct broth culture versus water lysis. Samples from 17 consecutive patients with dialysis-associated peritonitis were examined.

RESULTS

Of the 17 dialysates cultured, 14 (82.4%) were positive by one of the two methods. The final culture results agreed in 16 of 17 specimens (94.1%). The preliminary organism identification rate by Gram staining with the broth culture method was 70.6%, which was significantly greater than 17.6% by the water lysis method (p = 0.0019). In particular, the broth culture technique demonstrated superior Gram stain performance to identify Gram-positive organisms. Among the 13 dialysate samples positive by both methods, the broth culture method detected organisms faster than the water lysis method (1.3 +/- 0.7 vs. 2.6 +/- 1.6 days, p = 0.005).

CONCLUSIONS

Our results support the routine use of the broth culture technique using BacT/Alert blood culture bottles in order to facilitate early streamlining of empiric antibiotic therapy. Gram staining of sediments after centrifugation is associated with low diagnostic yield. Whether the lysis-centrifugation technique could provide additional value in case of peritonitis with a high likelihood of culture-negative results needs to be evaluated.

Enterobacteriaceae peritonitis complicating peritoneal dialysis: A review of 210 consecutive cases

Enterobacteriaceae peritonitis is a serious complication in peritoneal dialysis (PD), but the clinical course of PD-related Enterobacteriaceae peritonitis remains unclear. We reviewed all Enterobacteriaceae peritonitis in our dialysis unit from 1995 to 2004. During this period, there were 1748 episodes of peritonitis recorded; 210 episodes (12.0%) in 123 patients were caused by Enterobacteriaceae. The most common species was Escherichia coli, accounting for 111 episodes. The primary response rate was 84.8% and complete cure rate was 58.1%. The presence of exit site infection was associated with a lower complete cure rate (43.2 versus 61.3%, P = 0.034). A total of 82 episodes (39.0%) did not respond to single antibiotic treatment despite sensitivity in vitro, and a second antibiotic was added. Patients treated with two antibiotics had a marginally lower risk of relapse and recurrence than those with one antibiotic (21.4 versus 36.1%, P = 0.051). The episodes that had recent antibiotic therapy had a marginally lower complete cure rate (49.3 versus 62.8%, P = 0.06). There was a gradual increase in the prevalence of resistance to several commonly used antibiotics over the years. Recent antibiotic therapy was associated with resistance to cefotaxime, ceftazidime, cefoperazone/sulbactam, and piperacillin/tazobactam. We conclude that Enterobacteriaceae peritonitis is a serious complication of PD. Recent antibiotic therapy is the major risk factor of antibiotic resistance. Exit site infection, and probably recent antibiotic therapy, is associated with poor therapeutic response. Contrary to the current recommendation, treatment with two antibiotics may reduce the risk of relapse and recurrence.

Drug dosage in children with reduced renal function

Drug dosing in paediatric nephrology requires multiple considerations and is therefore time-consuming and error-prone. This review combines dose adjustment guidelines for children with renal failure and information on the immature renal function of neonates and premature babies in order to help both paediatric nephrologists and neonatologists estimate drug doses for their patients.

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

BACKGROUND

Corynebacterium species are part of the normal skin flora. The incidence of nosocomial infections caused by Corynebacterium species have increased substantially over the past two decades. However, the clinical course of Corynebacterium peritonitis complicating peritoneal dialysis remains unclear.

METHOD

We reviewed all the Corynebacterium peritonitis in our dialysis unit from 1995 to 2002. During this period, there were 1485 episodes of peritonitis recorded; 27 (1.8%) of which were caused by Corynebacterium species.

RESULTS

The underlying renal diagnosis and prevalence of comorbid conditions of the 27 patients were similar to our whole dialysis population. The bacteria isolated were resistant to penicillin in 8 cases (29.6%). Three cases (11.1%) had concomitant exit-site infection. The overall primary response rate was 74.1%; the complete cure rate was 37.0%. Episodes that received vancomycin as initial antibiotic had a marginally higher primary response rate (9 in 10 vs 11 in 17 episodes, P = 0.2) and complete cure rates (7 in 10 vs 3 in 17 episodes, P = 0.12) than the episodes that received cephalosporins, although neither of the differences was statistically significant. Thirteen cases (48.1%) had recurrent peritonitis after antibiotic therapy, 8 of which had the recurrent episode at least 30 days after stopping antibiotics (median 54 days, range 43-60 days). Eight recurrent cases (61.5%) were successfully cured by another 3 week course of intra-peritoneal vancomycin.

CONCLUSIONS

Recurrent Corynebacterium peritonitis is common after a 2 week course of antibiotics. Recurrent Corynebacterium peritonitis may be delayed up to 2 months after the antibiotic is stopped. Recurrent peritonitis can usually be cured with a 3 week course of intra-peritoneal vancomycin, which is probably the preferred antibiotic regimen for Corynebacterium peritonitis.

Efficacy of a non-vancomycin-based peritoneal dialysis peritonitis protocol

BACKGROUND

Peritonitis has a significant impact upon morbidity and mortality of peritoneal dialysis (PD) patients. Gram-positive organisms account for the majority of infections and vancomycin is a cost effective broad-spectrum antimicrobial treatment for PD peritonitis, but this may lead to the emergence of multiple antibiotic-resistant organisms. The purpose of the present paper was to evaluate the efficacy of a non-vancomycin-based protocol comprising cephazolin and gentamicin, which was introduced in the present PD population as empirical treatment for peritonitis.

METHODS

The study involved 82 peritonitis episodes over a 4-year period in 58 patients, excluding those with previous methicillin-resistant staphylococcal peritonitis.

RESULTS

With cephazolin and gentamicin there was no apparent difference in response or relapse rates in comparison to reported studies using vancomycin-based first-line therapy protocols.

CONCLUSION

We advocate initial treatment of PD peritonitis with non-vancomycin-based therapy given similar efficacy and the potential for reduction of resistant organisms.