Decrease in infections with the introduction of mupirocin cream at the peritoneal dialysis catheter exit site

Staphylococcus aureus associated peritonitis and catheter exit site infections (ESI) are an important cause of hospitalization and catheter loss in the patients undergoing chronic peritoneal dialysis (PD). We aimed to determine the potential effectiveness of the application of mupirocin cream at the catheter exit site in preventing exit site infection and peritonitis. METHODS: This prospective historically controlled study was done in a total of 86 patients who entered our PD program from April 1999 to January 2001. They were instructed to apply Mupirocin cream 2% to the exit site daily or on alternate days. The patients were not screened to determine whether they were staphylococcus aureus carriers. One hundred and thirteen patients on PD prior to April 1999 acted as historical controls. Both groups were followed prospectively for a period of 22 months. RESULTS: In the study group application of mupirocin lead to a significant reduction in the incidence rate of both exit site infections overall (0.43 vs. 0.09; p<0.0001) and ESI due staphylococcus aureus (0.14 vs. 0.02; p=0.004) amounting to a relative reduction of 79% and 85% respectively. Although the overall incidence of peritonitis did not change (0.28 vs. 0.26; p=0.7) there was a significant reduction in peritonitis caused by staphylococcus aureus (0.07 vs. 0; p=0.01) Although only one catheter required removal in the mupirocin group as against 5 in the control group, this was not statistically significant. CONCLUSIONS: Mupirocin application at the exit site significantly lowers the incidence of ESI and peritonitis caused by staphylococcus aureus without any significant side effects.     

Do topical antibiotics reduce exit site infection rates and peritonitis episodes in peritoneal dialysis patients? The Pan Thames Renal Audit

Background and objectives: Peritonitis is the major cause of peritoneal dialysis (PD) technique failure. Prophylactic topical antibiotics have been reported to reduce peritoneal dialysis catheter exit site infections (ESI) and peritonitis rates. Methods: We audited the effect of different exit site practices in the 12 Pan Thames and South East England PD centres, on ESIs and peritonitis between 2005 and 2008. Results: PD patients used prophylactic mupirocin (n=1,270), gentamicin (n=502) and no prophylactic antibiotics (n=1,203); annualised ESI rates were reduced with mupirocin (median 0.18, interquartile range [IQR] 0.13-0.23, patient episodes per year, vs. median 0.32, IQR 0.24-0.69, for no antibiotic prophylaxis, p<0.01). Gentamicin treatment was not significantly lower (median 0.29, IQR 0.21-0.47). Staphylococcal ESIs accounted for 39.6% in the no antibiotic group and fell to 25.7% with mupirocin and 28.2% with gentamicin. Despite the reduction in ESIs, there was no significant reduction in peritonitis rates (no antibiotics: median 0.56, IQR 0.5-0.65; mupirocin: median 0.55, IQR 0.53-0.75; and gentamicin: median 0.47, IQR 0.32-0.65). In particular, mupirocin did not reduce Staphylococcus aureus peritonitis rates. Conclusions: Topical antibiotics have been reported to reduce both ESI and peritonitis rates in controlled trials, and although in this audit of routine clinical practice, topical mupirocin did reduce overall ESI rates and both mupirocin and gentamicin reduced S. aureus ESIs, neither reduced overall peritonitis rates.     

Pseudomonas exit site infections in continuous ambulatory peritoneal dialysis patients.

The purpose of this study is to examine the natural history of Pseudomonas aeruginosa exit site infections in continuous ambulatory peritoneal dialysis (CAPD) patients treated with oral ciprofloxacin and local exit site care. A retrospective view was undertaken of 18 episodes of P. aeruginosa exit site infections developing in 17 patients maintained on CAPD during 1989 and 1990. Standardized therapy for the exit site infection consisted of oral ciprofloxacin (500 mg twice daily) and local exit site care with antiseptic agents. Fifteen (83%) of 18 of the pseudomonas exit site infections resolved with therapy. Three episodes (17%) required catheter removal to successfully eradicate the infection. Four of the 15 patients whose exit site infections resolved developed P. aeruginosa peritonitis 2 to 9 months after the clinical resolution of the exit site infection. The majority of pseudomonas exit site infections in CAPD patients can be successfully treated with oral ciprofloxacin and local care. Approximately 17% of the patients in this study required catheter removal to successfully eradicate the infection and an additional 22% of the patients developed pseudomonas peritonitis several months after the resolution of the exit site infection.     

A five-year study of the microbiologic results of exit site infections and peritonitis in continuous ambulatory peritoneal dialysis

We studied the culture results from 321 continuous ambulatory peritoneal dialysis (CAPD) related infections (exit site, tunnel infections, and peritonitis) in 137 patients over a 5-year period to determine the contribution of exit site and tunnel infections to peritonitis and catheter loss. Seventeen percent of peritonitis episodes were associated temporally and by microbiologic results with exit site or tunnel infections. Twenty-one percent of exit site and tunnel infections and 20% of peritonitis episodes resulted in catheter loss. Peritonitis due to Staphylococcus aureus was more likely to be associated with an exit site or tunnel infection and was more likely to result in loss of the catheter than peritonitis due to Staphylococcus epidermidis. Peritonitis and exit site infections due to Pseudomonas sp also frequently resulted in catheter removal. We found that exit site infections cause significant morbidity in CAPD patients. Further studies in this area are needed.     

Prevention of Peritonitis in Peritoneal Dialysis

Reducing the frequency of peritonitis for patients undergoing peritoneal dialysis (PD) continues to be a challenge. This review focuses on recent updates in catheter care and other patient factors that influence infection rates. An experienced nursing staff plays an important role in teaching proper PD technique to new patients, but nursing staff must be cognizant of each patient's unique educational needs. Over time, many patients become less adherent to proper dialysis technique, such as washing hands or wearing a mask. This behavior is associated with higher risk of peritonitis and is modifiable with re‐training. Prophylactic antibiotics before PD catheter placement can decrease the infection risk immediately after catheter placement. In addition, some studies suggest that prophylaxis against fungal superinfection after antibiotic exposure is effective in reducing fungal peritonitis, although larger randomized studies are needed before this practice can be recommended for all patients. Over time, exit site and nasal colonization with pathogenic organisms can lead to exit‐site infections and peritonitis. For patients with Staphylococcus aureus colonization, exit‐site prophylaxis with either mupirocin or gentamicin cream reduces clinical infection with this organism. Although there are limited data for support, antibiotic prophylaxis before gastrointestinal, gynecologic, or dental procedures may also help reduce the risk of peritonitis.     

New insights on preventing and managing peritonitis

Methods to prevent peritonitis are an essential component of any successful peritoneal dialysis (PD) program. Careful attention to training of the parents and child on the proper technique of PD and avoidance of manual spiking by using an assist device for the cycler, or use of the double-bag system for continuous ambulatory PD, should decrease risk of peritonitis from touch contamination. Secondly, reduction of peritonitis can be achieved through reduction of exit site infections by use of mupirocin antibiotic cream at the exit site of the PD catheter as part of routine care. If an exit site infection develops and is refractory to therapy, then the PD catheter can be successfully replaced as a single procedure, to reduce the risk of peritonitis. The third step in reducing the risk of peritonitis is to avoid repetitive episodes with the same organism. This may again involve replacing the catheter; as long as the effluent can be cleared, this again can be performed as a single procedure, thus allowing the child to avoid the trauma of hemodialysis. The focus in pediatric PD programs must always be on preserving the peritoneal membrane, and not on preservation of the catheter. With careful attention, peritonitis can become an uncommon event.     

A randomized controlled trial of topical exit site mupirocin application in patients with tunnelled, cuffed haemodialysis catheters.

BACKGROUND: Central venous catheters are frequently needed for the provision of haemodialysis, but their clinical usefulness is severely limited by infectious complications. The risk of such infections can be reduced by topical application of mupirocin to the exit sites of non-cuffed catheters or by the use of tunnelled, cuffed catheters. Whether mupirocin offers any additional protection against infection in patients with tunnelled, cuffed haemodialysis catheters has not been studied. METHODS: An open-label, randomized controlled trial was performed comparing the effect of thrice-weekly exit site application of mupirocin (mupirocin group) vs no ointment (control group) on infection rates and catheter survival in patients receiving haemodialysis via a newly inserted, tunnelled, cuffed central venous catheter. All patients were followed until catheter removal and were monitored for the development of exit site infections and catheter-associated bacteraemias. RESULTS: Fifty patients were enrolled in the study. Both the mupirocin (n=27) and control (n=23) groups were similar at baseline with respect to demographic characteristics, comorbid illnesses and causes of renal failure. Compared with controls, mupirocin-treated patients experienced significantly fewer catheter-related bacteraemias (7 vs 35%, P<0.01) and a longer time to first bacteraemia (log rank score 8.68, P<0.01). The beneficial effect of mupirocin was entirely attributable to a reduction in staphylococcal infection (log rank 10.69, P=0.001) and was still observed when only patients without prior nasal Staphylococcus aureus carriage were included in the analysis (log rank score 6.33, P=0.01). Median catheter survival was also significantly longer in the mupirocin group (108 vs 31 days, log rank score 5.9, P<0.05). Mupirocin use was not associated with any adverse patient effects or the induction of antimicrobial resistance. CONCLUSIONS: Thrice-weekly application of mupirocin to tunnelled, cuffed haemodialysis catheter exit sites is associated with a marked reduction in line-related sepsis and a prolongation of catheter survival.     

Routine use of mupirocin at the peritoneal catheter exit site and mupirocin resistance: still low after 7 years.

OBJECTIVE: The purpose of this study (the third in a series of similar studies) is to evaluate the prevalence of Staphylococcus aureus (SA), methicillin-resistant SA (MRSA) and mupirocin-resistant SA (MuRSA) carriers in a peritoneal dialysis centre where patients have been instructed to use prophylactic mupirocin ointment at the catheter exit site over the last 7 years. METHODS: Swabs were taken from catheter exit site, nares, axillae and groin in 147 chronic peritoneal dialysis out-patients between November 2003 and January 2004. Axillae/groin and nasal samples were pooled and cultured in the same medium, whereas exit site swabs were cultured separately. All SA isolated were tested for methicillin and mupirocin resistance using oxacillin screening plates and E-test strips. RESULTS: Sixteen of 147 patients (10.9%) were found to be SA carriers: of these 13 (8.8%) had a positive nasal/axillae/groin culture; two (1.4%) had both nasal/axillae/groin- and exit site-positive culture; and one (0.7%) had only exit site-positive culture. In these 16 SA carriers, we found mupirocin-resistant strains (MuRSA) in four patients (25%) and MRSA in two patients (12.5%). Among the four MuRSA carriers, one had both nasal/axillae/groin- and exit site-positive culture and three had only nasal/axillae/groin-positive culture. Three high-level resistance and one low-level resistance MuRSA carriers were isolated. One MuRSA strain was also methicillin resistant. All MRSA strains were sensitive to vancomycin and rifampicin. CONCLUSION: After 7 years' routine use of prophylactic mupirocin ointment at the catheter exit site in non-selected chronic peritoneal dialysis patients, MuRSA was found in 25% of SA strains isolated or in 2.7% of the patients. Compared with our previous study, 3 years earlier, there is no significant increase in the MuRSA prevalence in peritoneal dialysis patients who routinely apply mupirocin ointment at the catheter exit site.     

The impact of topical mupirocin on peritoneal dialysis infection in Singapore General Hospital.

BACKGROUND: Peritonitis and exit-site infections (ESI) are major causes of morbidity in peritoneal dialysis (PD) patients. The application of topical mupirocin to exit sites reduces such complications, and prolongs life in PD. Since the year 2000, this topical treatment has been used in our hospital on new PD patients. We analysed the results of this protocol, and studied the effects of comorbidities on the incidence of peritonitis. METHODS: We studied 740 incident PD patients, who were divided into two groups based on year of entry into PD (Group 1 from January 1998 to December 1999 inclusive, topical mupirocin not used, and Group 2 from January 2000 to March 2004 inclusive, topical mupirocin used). The variables we studied included gender, age, diabetic status, ischaemic heart disease, peripheral vascular disease, cerebrovascular disease and serum albumin. RESULTS: The application of topical mupirocin at the exit site led to a significant reduction in the rate of peritonitis (0.443 vs 0.339 episodes per patient-year; P<0.0005) and in ESI (0.168 vs 0.156 episodes per patient-year; P<0.005), results attributed primarily by the significant (P<0.005) reduction in Staphylococcus aureus infection. There was also an unexpected lowering of Pseudomonas aeruginosa peritonitis in the mupirocin group (P<0.005). Stepwise multiple logistic regression analysis revealed that only the application of mupirocin and serum albumin levels were significant predictors of peritonitis. CONCLUSIONS: Our study, although retrospective, has demonstrated that the topical use of mupirocin was associated with a significant reduction in ESI and peritonitis and, unexpectedly, with findings of fewer incidences of Pseudomonas peritonitis. Serum albumin level before the initiation of PD was a strong predictor of subsequent peritonitis. Mupirocin, with its low toxicity, ease of application and demonstrable beneficial effect in reducing ESI and peritonitis is now used on all of our incident PD patients.     

Effect of a silver device in preventing catheter-related infections in peritoneal dialysis patients: silver ring prophylaxis at the catheter exit study

Catheter-related infections remain a significant cause of method failure in chronic peritoneal dialysis (PD) therapy. Given the increasing antibiotic resistance, such nonpharmacological strategies as local silver devices attract more interest. To establish whether a silver ring device (designed by Grosse-Siestrup in 1992) mounted onto the PD catheter and placed at the exit site at skin level is effective in preventing exit-site and other catheter-related infections, a prospective 12-month, multicenter, controlled study stratified by diabetes status was conducted. The study subjects were assessed by an extensive structured inventory, including a broad spectrum of control variables, such as age, body mass index (BMI), Staphylococcus aureus carrier status, catheter features, mode and quality of PD therapy, comorbidity, and psychosocial rehabilitation. Ten experienced German outpatient dialysis centers (seven adult, three pediatric) participated in the trial. All eligible patients (n=195) from the study area without catheter-related infections during the ascertainment period were included (incidental subjects undergoing PD therapy for at least 3 months). The main outcome measures were the occurrence of first exit-site infections (primary study end point), sinus tract/tunnel infection, and peritonitis. Ninety-seven patients were assigned to the silver ring and 98 patients to the control group. Baseline characteristics of age, sex, proportion of pediatric and incidental patients, S aureus carrier status, and other variables were similar in both groups. The incidence of infections in the silver ring group versus the control group was as follows: 23 of 97 versus 16 of 98 patients had exit-site infections, 12 of 97 versus 12 of 98 patients had sinus tract/tunnel infections, 16 of 97 versus 18 of 98 patients had peritonitis, respectively. Kaplan-Meier analysis for the probability of an infection-free interval showed no statistical difference (log-rank test) between the two groups. Displacement of the silver ring contributed to study termination in 6% of the study group patients, including two patients with catheter loss. Univariate analysis and multiple logistic regression identified younger age (<50 years), low serum albumin level (<35 g/L), number of previously placed PD catheters, short cuff-exit distance (<2 cm), and S aureus nasal carriage as risk factors for the development of exit-site infections. In conclusion, our study does not show any benefit of the silver ring in preventing catheter-related infections in PD patients. Thus, prevention of infection-related method failure in PD still has to rely on conventional antibiotic treatment strategies and less so on alternative methods.     

Peritoneal infections

Peritoneal dialysis related infections include infection of the catheter exit site, subcutaneous pathway, or effluent. Exit-site infections, predominately owing to Staphylococcus aureus, are defined as purulent drainage at the exit site, although erythema may be a less serious type of exit-site infection. Tunnel infections are underdiagnosed clinically, and sonography of the tunnel is useful to delineate the extent of the infection and to evaluate response to antibiotic therapy. S aureus infections occur more frequently in S aureus carriers and immunosuppressed patients and can be reduced by mupirocin prophylaxis either intranasally or at the exit site. Patients with peritonitis present with cloudy effluent and usually pain, although 6% of patients may initially have pain without cloudy effluent. A white blood cell count of 100 or greater per microL, 50% of which are polymorphonuclear cells, has long been the hallmark of peritonitis. Empiric therapy is controversial, with some recommending cefazolin and others vancomycin (with cefatazidime for Gram-negative coverage). The choice should depend on the center's antibiotic sensitivity profile; those centers with a high rate of Enterococcus- or methicillin resistant organisms should use vancomcycin. Peritonitis episodes occurring in association with a tunnel infection with the same organism seldom resolve with antibiotics and require catheter removal. Other indications for catheter removal are refractory peritonitis, relapsing peritonitis, tunnel infection with inner-cuff involvement that does not respond to antibiotic therapy (based on ultrasound criteria), fungal peritonitis, and enteric peritonitis owing to intra abdominal pathology. Centers can reduce dialysis related infections to very low levels by proper catheter selection and insertion, careful selection and training of patients, avoidance of spiking techniques, and use of antibiotic prophylaxis against S. aureus. Further research is required to identify methods to reduce the risk of enteric peritonitis.     

The impact of topical mupirocin on peritoneal dialysis infection rates in Singapore General Hospital.

BACKGROUND: Peritonitis and exit-site infections (ESI) are major causes of technique failure and morbidity in peritoneal dialysis (PD) patients. Topical mupirocin on the exit-site has been shown to reduce such complications and prolong life in PD. Since the year 2000, such an approach has been adopted for our new incident PD population. We now report the results of this new protocol. We also studied the effect of co-morbidity on peritonitis occurrence. METHODS: A total of 740 incident PD patients were studied. Patients were divided into two groups based on year of entry into PD (Group 1 from January 1998-December 1999 without topical mupirocin and Group 2 from January 2000-March 2004 with topical mupirocin). Variables studied included gender, age, diabetic status, ischaemic heart disease, peripheral vascular disease, cerebrovascular disease and serum albumin. RESULTS: Topical mupirocin at the exit-site has led to a significant reduction in peritonitis rate (0.443 vs 0.339 episodes/patient-year; P<0.0005) and ESI (0.168 vs 0.156 episodes/patient-year; P<0.005) attributed primarily to the significant reduction in Staphylococcus aureus infections. There was an unexpected finding of lower Pseudomonas aeruginosa peritonitis in the mupirocin group (P<0.005). Stepwise multiple logistic regression analysis revealed that only mupirocin application and serum albumin were significant predictors of peritonitis. CONCLUSIONS: Our study, although limited by its retrospective nature, demonstrated that topical mupirocin was associated with a significant reduction in ESI and peritonitis with unexpected findings of lower Pseudomonas peritonitis. Serum albumin prior to the initiation of PD was a strong predictor of subsequent peritonitis. Mupirocin, with its low toxicity, ease of application and demonstrable beneficial effect in reducing ESI and peritonitis is now used on all incident PD patients.     

Mupirocin application at the exit site in peritoneal dialysis patients: five years of experience

Introduction: In this study, we aimed to analyze the effects of once- or thrice-weekly mupirocin application on peritonitis, exit-site infection (ESI), and antibiotic resistance with mupirocin. Patients and methods: By 2000 mupirocin began to be applied once a week to 33 patients who previously did not use mupirocin at the exit site. By the beginning of 2002, the patients were assigned to two groups. In group I patients continued to apply mupirocin once a week. In group II patients began to apply mupirocin to the exit site three times weekly and we began to obtain cultures from the nares, inguinal area, axillae, and the exit site. Results: A total of 28 episodes of ESI and 41 episodes of peritonitis were seen in 33 patients prior to mupirocin treatment, while a total of 14 episodes of ESI and 34 episodes of peritonitis were observed in all groups of patients who used mupirocin. In a subgroup analysis, 13 episodes of peritonitis and 7 episodes of ESI were determined in group I, while 6 episodes of peritonitis and 1 episode of ESI were determined in group II. Staphylococcus aureus reproduction rate and mupirocin resistance were 2.11 and 0.2%, respectively. Coagulase-negative staphylococcus reproduction rate was 70.56% (MuR: 59.87% and MeR: 33.7%) and 72.6% (MuR: 64.7% and MeR: 33.3%) in groups I and II, respectively. Conclusion: Mupirocin application at the exit sites reduces peritonitis and ESI to a considerable amount, and thrice-weekly application of mupirocin seems to be more efficient compared to once-weekly application.     

Preventing Staphylococcus aureus infection during chronic peritoneal dialysis.

In the interest of studying the prevention of chronic peritoneal dialysis infections, serial studies of the bacterial epidemiology in peritonitis and of antibiotic prophylaxis, respectively, were carried out. For 18 months, prospective evaluation of catheter exist site cultures, performed at the time patients developed acute peritonitis, showed that Staphylococcus aureus peritonitis was associated with concordant S. aureus at the exist site in 85% of cases, significantly more frequent than that for other organisms (P less than 0.02). Furthermore, active inflammation along with concordant culture results at the exit site characterized more than 60% of S. aureus peritonitis cases, also significantly more than that for other organisms (P less than 0.01). Over the ensuing 2 yr, patients beginning chronic peritoneal dialysis with a new percutaneously placed catheter were prospectively entered into a randomized, controlled trial of long-term antibiotic prophylaxis with trimethoprim-sulfamethoxasole. Patients receiving prophylaxis tended to have fewer episodes of peritonitis; however, the lower rate of peritonitis reached statistical significance only comparing patients who were S. aureus carriers at entry into the study to patients who were not S. aureus carriers. In particular, the prophylaxis trial seemed to reduce the specific incidence of S. aureus peritonitis overall, with S. aureus appearing in only 2 of 28 total peritonitis episodes among treated patients as compared with 11 of 37 total episodes among non-treated patients (P less than 0.01). Further analysis of the time to first peritonitis suggests that the effect of prophylaxis was most prominent during the first 3 months of therapy (P less than 0.02) rather than later in the course of treatment.(ABSTRACT TRUNCATED AT 250 WORDS)     

Methicillin-resistant staphylococcal infections in an outpatient peritoneal dialysis program

In view of the increasing concern about hospital-acquired methicillin resistance, we examined the sensitivities and outcome of staphylococcal infections related to outpatient peritoneal dialysis over a 5-year period. Data on all episodes of peritonitis (n = 360) and catheter infections (n = 507) were gathered prospectively from January 1984 to December 1988. The numbers of patients on peritoneal dialysis each year ranged from 136 in 1984 to 109 in 1987. Fifteen methicillin-resistant staphylococcal infections (MRSI) related to outpatient peritoneal dialysis occurred. Three were due to methicillin-resistant Staphylococcus aureus found in infected exit sites (2.3% of all S aureus catheter infections). Two of these infections occurred in a continuous ambulatory peritoneal dialysis (CAPD) patient who carried methicillin-resistant S aureus in his nares. The other 12 methicillin-resistant organisms were coagulase-negative staphylococci that caused peritonitis. There was a significant increase in the percentage of episodes of coagulase-negative staphylococci peritonitis caused by methicillin-resistant organisms; from 5% (3/57) in 1984 through 1986 to 28% (9/32) in 1987 through 1988 (P less than 0.005). In view of the high percentage of coagulase-negative staphylococci peritonitis that is methicillin-resistant, vancomycin rather than cephalosporins should be used for initial treatment.     

Management of bacterial peritonitis and exit‐site infections in continuous ambulatory peritoneal dialysis*

SUMMARY: Peritonitis and exit‐site infections remain the most important limitations to the delivery of continuous ambulatory peritoneal dialysis (CAPD). Contamination of the peritoneum, from endogenous or exogenous sources, is responsible for most peritonitis episodes. Patients usually present with a cloudy bag, although other causes should be distinguished. Clinical suspicion of peritonitis should be followed rapidly by microbiological examination and empirical treatment. Microbiological confirmation allows for subsequent treatment based on sensitivities. Other interventions such as catheter removal may be appropriate in some patients. Exit‐site infections should also be identified and treated early. Peritonitis may be further prevented by adequate exit‐site care, hygienic methods, and techniques to minimise early contamination of the exit site. Mupirocin may also have a role in preventing infections caused by Staphylococcus aureus.     

Infection with antimicrobial-resistant microorganisms in dialysis patients

The prevalence of antimicrobial-resistant microorganisms in various health care settings, including outpatient dialysis facilities, has increased dramatically in the last decade. Antimicrobial use and patient-to-patient transmission of resistant strains are the two main factors that have contributed to this rapid increase. Methicillin-resistant Staphylococcus aureus (MRSA) and coagulase-negative staphylococci are commonly isolated as a cause of hemodialysis (HD) catheter-related bacteremia and peritoneal dialysis (PD)-related catheter infection and peritonitis. The widespread use of vancomycin in dialysis patients is of concern because of an increase in the prevalence of vancomycin-resistant enterococci (VRE) in dialysis patients. Staphylococci with reduced sensitivity to vancomycin have also appeared in dialysis patients. A more recent problem is the appearance of S. aureus isolates with a high degree of resistance to the topical antimicrobial agent mupirocin. This has been seen in PD patients who have received prophylactic application of mupirocin at the peritoneal catheter exit site. Appropriate antimicrobial use will help protect the efficacy of currently used antibiotics, such as vancomycin. Published guidelines for use of vancomycin should be followed. New antimicrobials such as linezolid and quinupristin/dalfopristin have activity against VRE and MRSA, but resistance to these agents has already occurred. Preventing transmission of antimicrobial-resistant microorganisms in health care settings, including outpatient dialysis facilities, is important in limiting the spread of these resistant organisms.     

Use of pulsed-field gel electrophoresis in the analysis of recurrent Staphylococcus aureus infections in patients on continuous ambulatory peritoneal dialysis

BACKGROUND/AIM: The purpose of this study was to evaluate pulsed-field gel electrophoresis (PFGE) for distinguishing between relapse and reinfection of Staphylococcus aureus infections in patients on continuous ambulatory peritoneal dialysis (CAPD). METHODS: Between July 1993 and May 1997, 4 patients with recurrent CAPD-associated infections caused by S. aureus we enrolled in this study. There were nine episodes of peritonitis, one episode of temporary double lumen catheter infection, and one episode of Hickman catheter infection. A total of eleven S. aureus isolates were collected from peritoneal fluid (n = 9) and blood (n = 2). PFGE typing was applied. RESULTS: In our study, from PFGE typing, the 11 S. aureus isolates were classified into seven patterns. Antibiogram profiling classified only four patterns. Patient A had a reinfection by another strain of S. aureus, and patient B had three episodes of peritonitis caused by the same strain of S. aureus due to exit site infections. Patient C had two episodes of CAPD peritonitis caused by two different strains, respectively. Patient D had four episodes of S. aureus infection (three CAPD peritonitis and one bacteremia); the first two episodes of peritonitis were caused by an identical strain of S. aureus, whereas the subsequent two infections were caused by other organisms. CONCLUSION: PFGE has a high discriminatory power and can be an assistant method to antibiogram profiling for distinguishing relapse from reinfection in CAPD-associated peritonitis.     

Incidence and clinical significance of nasal and pericatheter colonization by Gram-negative bacteria among patients undergoing chronic peritoneal dialysis.

BACKGROUND: Nasal and pericatheter colonization by Staphylococcus aureus portends an increased risk of peritonitis and exit-site infection for peritoneal dialysis (PD) patients. The aim of the present study was to examine the incidence of colonization by other peritoneal pathogens, and more specifically by Gram-negative bacteria (GNB), among PD patients, and to disclose its potential correlation with PD-related infections. METHOD: Over a 3-year period, we prospectively screened 152 PD patients and 99 partners every other month for nasal and pericatheter bacterial colonization (total follow-up for patients 3182 months). We performed 1089 studies in patients and 561 in partners. RESULTS: Although S. aureus and coagulase-negative Staphylococcus spp. predominated both in patients and partners, we recovered GNB from 15.8% (nares) and 22.4% (pericatheter) of the patients and from 29.3% of the partners. Most isolations of GNB were transient and only 7.2% of the patients and 7.1% of the partners had the same GNB isolated in at least two controls from the same sampling site. Older age, male gender, longer follow-up on PD, previous immunosuppressive therapy, low socioeconomic conditions, and a high global incidence of peritonitis were predictive of colonization by GNB. Previous pericatheter mupirocin therapy was also associated with later colonization by GNB. Nasal or pericatheter colonization by bacteria other than S. aureus, particularly GNB, had a poor predictive power for PD-related infections. CONCLUSION: Nasal and pericatheter bacterial colonization is protean in PD patients and their partners, and includes the significant presence of potentially pathogenic GNB. Colonization by GNB was not clearly associated with an increased risk of peritonitis or exit-site infection in these patients.     

Peritoneal fluid and solute transport: influence of treatment time, peritoneal dialysis modality, and peritonitis incidence

The integrity of the peritoneal membrane in peritoneal dialysis (PD) is of major importance for adequate dialysis and fluid balance. However, alterations in peritoneal fluid transport, such as ultrafiltration failure, often develop during long-term PD. To investigate peritoneal solute and fluid transport and to analyze the influence of treatment time, peritonitis incidence, and PD modality (continuous ambulatory PD [CAPD] or automated PD [APD]), a cross-sectional study with an extended peritoneal transport test that used dextran 70 in 2 L of glucose was performed in 23 nonselected chronic PD patients. Compared were long-term (>40 mo) with short-term PD patients (<40 mo), CAPD with APD patients, and those with a peritonitis incidence of >0.25/yr to those with an incidence of <0.25/yr. Dialysate/plasma (D/P) ratio and mass transfer area coefficient of creatinine, lymphatic absorption rate (LAR), transcapillary ultrafiltration, and effective ultrafiltration were measured. Long-term PD patients had higher D/P ratio of creatinine (73.5 +/- 2.3% versus 65.9 +/- 2.2%; P < 0.01) and higher LAR (243 +/- 69 ml/4 h versus 96 +/- 31 ml/4 h; P < 0.03), both resulting in lower effective ultrafiltration (242 +/- 35 ml/4 h versus 324 +/- 30 ml/4 h; P < 0.05). D/P ratio (r = 0.66) and LAR (r = 0.67) were positively correlated to PD duration. Patients on APD compared with those on CAPD and patients with a history of peritonitis compared with those without did not differ in terms of D/P ratio, mass transfer area coefficient, LAR, transcapillary ultrafiltration, and effective ultrafiltration. Lower ultrafiltration after long-term PD is both the result of increased small solute transport and increased lymphatic absorption. APD or CAPD modality and peritonitis incidence do not have a significant influence on small solute transport or fluid kinetics.