Peritonitis in continuous ambulatory peritoneal dialysis: impact of a compulsory switch from a standard to a Y-connector system in a single North American Center

Chronic Peritoneal Dialysis: Seven-Year Experience in a Large Hispanic Program

Objective

To analyze the clinical results of our patient population on continuous ambulatory peritoneal dialysis (CAPD) and continuous cycling peritoneal dialysis (CCPD) in relation to treatment modality systems, compliance, rehabilitation characteristics, complications, and survivals.

Design

The medical records of all patients trained on CAPD or CCPD between 1985 and 1992 were reviewed for the above-mentioned outcome objectives.

Setting

Outpatient CAPD facility affiliated to a tertiary care community hospital.

Patients

The total of 305 patients trained during the study period were studied.

Main Outcome Measures

The patients were studied for age, sex, primary renal disease, peritoneal dialysis modality, need of assistance from a partner during the dialysis procedure, causes of transfer and hospitalization, peritonitis, rehabilitation, patient compliance, and outcome including mortality.

Results

Patient population: 179 (58.7%) males and 126 (41.3%) females, aged 1-80 years(mean47.2±15.09) with a total observation time of 15753 patient-months. The most common diagnosis of the renal disease was diabetic nephropathy (41%). Peritonitis was the main cause of hospitalizations(36.7%) and of transfers (69.5%). Patient survival at one, two, and three years was 87.9%, 76.6%, and 67.0%, respectively. Likewise, technique survival was 65.5%,45.5%, and 30.6%. Peritonitis rate for CAPD has improved from 1.9 episodes per patient-year to 1.2 episodes per patient-year and an overall rate of 1.5 episodes per patient-year.

Conclusions

The experience in a large Hispanic program shows a good patient survival rate. Although there is a trend to a lower peritonitis rate, this continues to be the main cause of transfer, hospitalization, and one of the main causes of death.

Continuous Ambulatory Peritoneal Dialysis Connection Systems

The history of the various connection systems proposed and tried during the first 15 years of clinlcal application of continuous ambulatory peritoneal dialysis (CAPD) is reviewed.

In order to understand the reasons for their success or lack of success, the main technical and operating characteristics regarding their efficacy In preventing peritonitis are examined in detail, together with a range of other pros and cons (I.e., reliability, simplicity, ease of use, cost, aesthetlcal aspects).

The result Is an updated state-of-the-art review In the field of CAPD connectology, with a look at future trends.

A Prospective Randomized Study of the Effect of a Subcutaneously “Buried” Peritoneal Dialysis Catheter Technique versus Standard Technique on the Incidence of Peritonitis and Exit-Site Infection

♦ Objective

A new method for implantation of peritoneal dialysis (PD) catheters was described in 1991. The distal part of the catheter is buried subcutaneously and exteriorized at the start of PD. This study was designed to evaluate the effect of such a subcutaneous rest period on the incidence of peritonitis and exit-site infections (ESI).

♦ Design

Sixty patients were randomized to either the new method (B group; n = 30) or to not having the distal part buried subcutaneously (NB group; n = 30). Sixty-five patients (NS group) were not randomized as they had to start PD within 1 – 2 weeks after implantation. The Moncrief–Popovich catheter was used in the B and NB groups and a standard Tenckhoff catheter was used in the NS group.

♦ Patients

Patients scheduled for PD treatment, judged not in need of PD for at least 6 weeks after implantation.

♦ Results

There was no statistically significant difference in the cumulative probability of not developing peritonitis during the first 6, 12, and 24 months. The incidence of the first episode of peritonitis was 1/40, 1/26, and 1/33 treatment-months in the B, NB, and NS groups, respectively. The incidence of ESI was 1/103 and 1/95 treatment-months in the B and NS groups, respectively. The cumulative probability of not developing ESI was similar in both groups. There were no episodes of ESI in the NB group. The difference in the number of ESI between the NB and NS groups was significant ( p < 0.05).

♦ Conclusions

Subcutaneous burying of the distal catheter segment prior to starting PD does not reduce the risk of contracting peritonitis or exit-site infection.

Improving Outcome of Capd: Twenty-Five Years’ Experience in a Single Korean Center

Background

Continuous ambulatory peritoneal dialysis (CAPD) is an established treatment for end-stage renal disease (ESRD). We investigated the outcome of CAPD over a period of 25 years at our institution.

Methods

CAPD has been performed in 2301 patients in 25 years. After excluding patients with less than 3 months of follow-up and missing data, we evaluated 1656 patients who started peritoneal dialysis between November 1981 and December 2005. Data for sex, age, primary disease, co-morbidities, follow-up duration, cause of death, and cause of technique failure were collected. We also examined data for urea kinetic modeling (UKM), beginning in 1990, and peritonitis episodes, including causative organisms, starting in 1992.

Results

Compared to incident patients from 1981 – 1992, mean age and incidence of ESRD caused by diabetic nephropathy increased in patients from 1993 to 2005. Technique survival after 5 and 10 years was 71.9% and 48.1% respectively. Technique survival was significantly higher in patients who started CAPD after 1992 than in those who started before 1992. Peritonitis was the main reason for technique failure. Overall peritonitis rate was 0.38 episodes per patient-year, with a significant downward trend to 0.29 per patient-year over 10 years, corresponding to a decrease in gram-positive peritonitis. Patient survival after 5 and 10 years was 69.8% and 51.8% respectively. Patient survival improved significantly during 1992 – 2005 compared to 1981 – 1992 after adjustment for age, gender, diabetes, and cardiovascular comorbidities [hazard ratio (HR) 0.68, p < 0.01]. Subgroup analysis based on UKM revealed that dialysis adequacy did not affect patient survival. However, diabetes (HR 2.78, p < 0.001), older age (per 1 year: HR 1.06; p < 0.001), serum albumin level (per 1 g/dL: increase, HR 0.52; p < 0.05), and cardiovascular comorbidities (HR 2.32, p < 0.01) were identified as significant risk factors.

Conclusion

Technique survival has improved due partly to a decrease in peritonitis, which was attributed to a decrease in gram-positive peritonitis. Patient survival has also improved considering increases in aged patients and ESRD caused by diabetes. The mortality rate of CAPD is still high in older, diabetic, malnourished, and cardiovascular diseased patients. A more careful management of higher risk groups will be needed to improve the outcome of CAPD patients in the future.

A comparison of peritonitis rates from the United States Renal Data System database: CAPD versus continuous cycling peritoneal dialysis patients

BACKGROUND

Previous comparisons of peritonitis rates between continuous ambulatory peritoneal dialysis (CAPD) and continuous cycling peritoneal dialysis (CCPD) have produced varying results.

METHODS

Using United States Renal Data System data, the authors evaluated peritonitis rates in 1994 through 1997 incident CAPD (n = 9,190) and CCPD (n = 2,785) Medicare patients. Patients were characterized during a 6-month entry period (months 4 through 9) and followed for a maximum of 2 years (months 10 through 33). Medicare claims data provided the date of the first peritonitis episode during the follow-up period. The time to first peritonitis after 9 months of PD was compared by the log-rank test, and then by Cox regression with adjustment for peritoneal dialysis modality, age, sex, race, primary end-stage renal disease (ESRD) diagnosis, number of entry-period hospital days, peritonitis during the entry period, hematocrit value, and congestive heart failure.

RESULTS

For CAPD and CCPD, the adjusted average months to first peritonitis after 9 months of PD were 17.1 and 16.1, respectively. The probabilities of remaining without a peritonitis episode after 1 year of follow-up were 0.53 and 0.50, respectively ( P = 0.008). The risk of peritonitis was lower for CAPD than for CCPD (relative risk, 0.939; 95% confidence interval, 0.883 to 0.998). Other significant risk factors included age <or=44 years, black race, diabetes as primary ESRD diagnosis, peritonitis during the entry period, greater than 4 entry-period hospital days, and congestive heart failure. Patients treated with recombinant human erythropoietin with a hematocrit value of >or=36% had lower risk of peritonitis.

CONCLUSION

Compared with CCPD, CAPD is associated with a slightly but significantly lower risk for development of a first peritonitis episode after 9 months of peritoneal dialysis therapy.

Peritonitis in an urban peritoneal dialysis program: an analysis of infecting pathogens

We have previously found that race, level of education, and peritoneal dialysis system are factors that significantly and independently influence peritonitis rates in our patient population. We now extend these observations by assessing the pathogens responsible for peritonitis in these subgroups. Between January 1, 1981, and May 15, 1993, 248 peritoneal dialysis patients underwent dialysis at our facility. The rate of peritonitis by pathogen was determined in these patients using the fixed effects Poisson model. Total peritonitis rates in black patients (1.89 episodes/patient-year) were significantly greater compared with white patients (1.11 episodes/patient-year; P < 0.0001). Increased infection rates in black patients were significant for Staphylococcus epidermidis, Staphylococcus aureus, and gram-negative pathogens. The level of education had a negative correlation with peritonitis rates (< or = 8 years, 2.00 episodes/patient-year; 9 to 12 years, 1.64 episodes/patient-year; and > or = 13 years, 1.24 episodes/patient-year) with patients having > or = 13 years of education at the start of dialysis demonstrating a significantly lower total peritonitis rate compared with patients with 9 to 12 years (P = 0.001) or < or = 8 years (P < 0.001) of education. This was accounted for by a significant decrease in infection rates for S epidermidis, polymicrobial, and gram-negative organisms. Finally, patients on automated peritoneal dialysis had significantly lower total peritonitis rates (0.59 episodes/patient-year) compared with patients on either a connect (2.11 episodes/patient-year) or disconnect (1.46 episodes/patient-year) system.(ABSTRACT TRUNCATED AT 250 WORDS)

Continuous ambulatory peritoneal dialysis for patients with severe left ventricular systolic dysfunction and end-stage renal disease

To better define the survival and quality of life of patients with major left ventricular systolic dysfunction and end-stage renal disease treated by continuous ambulatory peritoneal dialysis (CAPD), we reviewed all cases who started CAPD between May 1984 and March 1993 who had an isotopic left ventricular ejection fraction (LVEF) < or = 35%. Seventeen patients (12 men and five women with a mean age of 51.6 +/- 14.9 years) met the inclusion criteria. Mean isotopic LVEF before initiation of CAPD was 24.8% +/- 8.2%. All patients were symptomatic from congestive heart failure. Thirteen patients were classified as New York Heart Association grade III or IV. Continuous ambulatory peritoneal dialysis was associated with a significant improvement of isotopic LVEF, of functional status, and of blood pressure control. In 10 patients with a second measurement on CAPD, LVEF increased from a mean value of 23.2% +/- 9.1% to a mean value of 30.3% +/- 8.1% (P < 0.01). This represents a 30% increase of LVEF. After 6 months on CAPD, 94% of patients were classified as New York Heart Association grade I or II. Actuarial survival rates were 94%, 80%, and 64% at 12, 18, and 24 months, respectively. The mean duration of CAPD was 24 +/- 17 months. These results suggest that current CAPD treatment is an elective modality of treatment in patients with concomitant heart and renal failure.

Race and the risk of peritonitis: an analysis of factors associated with the initial episode

To study how clinical characteristics influence the risk of peritonitis in African American patients with end-stage renal disease treated with continuous ambulatory peritoneal dialysis (CAPD), we examined the risk of developing a first episode of peritonitis among 1,595 new dialysis patients initially treated by CAPD over a two year period in North Carolina, South Carolina, and Georgia (Network 6). Characteristics examined were demographic and socioeconomic factors, functional status, serum albumin and comorbid conditions. There were 538 initial episodes of peritonitis during an average of 8.8 patient months of follow-up; the time to peritonitis for the entire cohort was 26 months. Factors found to be independently associated with a risk for peritonitis were student status (Odds Ratio and 95% Confidence Interval = 2.4; 1.4 to 4.3), rental housing (1.2; 1.0 to 1.5), and substance abuse (1.9; 1.1 to 3.2). African Americans were 60% more likely to have an initial episode of peritonitis during follow-up than whites (1.6; 1.3 to 1.8). The time to the initial episode was 21 months for African Americans versus 32 months for whites (P < 0.001). Even after adjusting for other factors, African Americans were significantly more likely to develop peritonitis (1.5; 1.2 to 1.8). Thus, the increased risk of peritonitis of African American patients treated by CAPD is independent of other demographic, socioeconomic and comorbid characteristics.

Infecting organisms in continuous ambulatory peritoneal dialysis patients on the Y-set

Disconnect systems for performing continuous ambulatory peritoneal dialysis (CAPD) use a flush-before-fill technique that should theoretically reduce the peritonitis caused by touch contamination. However, little information about the infecting organisms in CAPD-related infections using disconnect systems is available. We performed a retrospective matched-case controlled study to define the organisms responsible for the peritonitis and catheter infections seen in CAPD patients using the Y-set without disinfectant. One hundred nineteen patients who began CAPD on the Y-set were matched with 119 patients who began CAPD on the standard spike system. Patients were matched for age, sex, race, insulin dependence, and time on CAPD. Infection data were prospectively collected for all patients. Peritonitis, exit site, and tunnel infection rates (expressed as number of episodes per patient-year) were all significantly lower in the Y-set patients (0.56 v 0.94, 0.68 v 1.08, and 0.14 v 0.22, respectively). The lower peritonitis rate in the Y-set patients compared with that found in the standard spike system patients was due to a reduction in Staphylococcus epidermidis (0.17 v 0.26, P = 0.02), polymicrobial (0.014 v 0.06, P = 0.01), other gram-positive (0.007 v 0.09, P = 0.001), and sterile (0.10 v 0.19, P = 0.008) peritonitis. Rates of Staphylococcus aureus and gram-negative peritonitis were not different among the two groups. S epidermidis (0.12 v 0.23, P = 0.0014) and gram-negative (0.12 v 0.18, P = 0.04) exit site infection rates were also lower in the Y-set patients.(ABSTRACT TRUNCATED AT 250 WORDS)