Peritonitis in recent years: clinical findings and predictors of treatment response of 170 episodes at a single Brazilian center

Linking clinical manifestations and causative organisms may provide clues for the treatment of peritoneal dialysis-associated peritonitis

INTRODUCTION

Different initial manifestations of peritoneal dialysis-associated peritonitis (PDAP) may depend on the type of pathogenic organism. We investigated the association between the clinical characteristics of PDAP and susceptibility to vancomycin and investigated the possibility of using vancomycin monotherapy alone as an initial treatment regimen for some PDAP patients to avoid unnecessary antibiotic exposure and secondary infection.

METHODS

Patients with culture-positive PDAP were retrospectively analyzed and divided into two groups: peritonitis with only cloudy effluent (PDAP-cloudy) or with cloudy effluent, abdominal pain and/or fever (PDAP-multi). The bacterial culture of PD effluent and antibiotic sensitivity test results were compared between groups. Logistic regression was used to investigate factors predicting susceptibility to vancomycin.

RESULTS

Of 162 episodes of peritonitis which had a positive bacterial culture of PD fluid, 30 peritonitis were in the PDAP-cloudy group, and 132 peritonitis were in the PDAP-multi group. Thirty (100%) peritonitis in the PDAP-cloudy group had gram-positive bacterial infections, which was significantly greater than that in the PDAP-multi group (51.5%) (P < 0.001). Twenty-nine (96.7%) peritonitis in the PDAP-cloudy group were susceptible to vancomycin, compared to 67 (50.8%) in the PDAP-multi group (P < 0.001). The specificity of PDAP-cloudy for vancomycin-sensitive peritonitis was 98.48%. Only one patient (3.3%) in the PDAP-cloudy group experienced vancomycin-resistant peritonitis caused by Enterococcus gallinarum, which could neither be covered by vancomycin nor by the initial antibiotic regimen recommended by the current ISPD guidelines. The presence of only cloudy effluent was an independent predictor of susceptibility to vancomycin according to multivariate analysis (OR = 27.678, 95% CI 3.191-240.103, p = 0.003), in addition to PD effluent WBC counts (OR = 0.988, 95% CI 0.980-0.996, p = 0.004), diabetes mellitus (OR = 3.646, 95% CI 1.580-8.416, p = 0.002), first episode peritonitis (OR = 0.447, 95% CI 0.207-0.962, p = 0.039) and residual renal creatinine clearance (OR = 0.956, 95% CI 0.918-0.995, p = 0.027). Addition of these characteristics increased the AUC to 0.813 (95% CI 0.0.749-0.878, P < 0.001). The specificity of presenting with only cloudy effluent for vancomycin-sensitive peritonitis was 98.48%.

CONCLUSIONS

Cloudy dialysate, as the only symptom at PDAP onset, was an independent predictor of vancomycin-sensitive PDAP, which is an important new insight that may guide the choice of initial antibiotic treatment.

Successfully Treated Roseomonas mucosa-induced Peritonitis Diagnosed by Mass Spectrometry

Roseomonas mucosa is difficult to identify using routine analytical techniques. We herein report a case of peritoneal dialysis (PD)-related peritonitis caused by R. mucosa identified using matrix-assisted laser desorption/ionization-time-of-flight (MALDI-TOF) mass spectrometry (MS). A 70-year-old woman was admitted to our hospital with PD-related peritonitis. Blood agar medium of dialysate culture derived colony pale pink in color, and the organism was identified as R. mucosa using MALDI-TOF MS. She was successfully treated with ciprofloxacin and meropenem without catheter removal. To our knowledge, this is the first case of R. mucosa peritonitis in which technique failure has been avoided.

Listeria monocytogenes-associated spontaneous bacterial peritonitis in France: a nationwide observational study of 208 cases

BACKGROUND

Listeriosis is a foodborne infection caused by Listeria monocytogenes. Three main forms of listeriosis are well characterised, but little is known about L monocytogenes-associated spontaneous bacterial peritonitis. We used data from the French national surveillance of listeriosis to perform a nationwide retrospective study.

METHODS

All patients with L monocytogenes isolated by culture from a peritoneal fluid sample in France between April 1, 1993, and Dec 31, 2022, were included. Individuals for whom bacterial peritonitis was not confirmed and those who also had another type of invasive listeriosis were excluded. A standardised checklist was used to collect demographic, clinical, and biological data as well as antibiotic treatment and follow-up data. The primary outcome was to determine the characteristics of L monocytogenes-associated spontaneous bacterial peritonitis. We did descriptive analyses and assessed risk factors for 1-month mortality using an exploratory multivariable Cox model analysis.

FINDINGS

Among the 8768 L monocytogenes cases reported, 208 (2%) were patients with L monocytogenes-associated spontaneous bacterial peritonitis. Mean age was 65 years (SD 13), 50 (24%) of 208 patients were female, and 158 (76%) were male (no data on race or ethnicity were available). 200 (98%) of 205 patients with L monocytogenes-associated spontaneous bacterial peritonitis with available data had immunosuppressive comorbidities, including cirrhosis (148 [74%] of 201 with available data), ongoing alcoholism (58 [62%] of 94), and ongoing neoplasia (60 [31%] of 195). Causes of ascites included cirrhosis (146 [70%] of 208), ongoing neoplasia (26 [13%]), end-stage heart failure (13 [6%]), and peritoneal dialysis (11 [5%]). Among those with available data, presentation was pauci-symptomatic and non-specific; only 67 (50%) of 135 patients presented with fever, 49 (37%) of 132 with abdominal pain, and 27 (21%) of 129 with diarrhoea. 61 (29%) of 208 patients were dead at 1 month, 92 (44%) were dead at 3 months, and 109 (52%) were dead at 6 months after diagnosis. Ongoing neoplasia (hazard ratio 2·42 [95% CI 1·05-5·56]; p=0·039), septic shock (8·03 [2·66-24·02]; p=0·0021), and high blood leukocyte count (1·05 [1·00-1·09]; p=0·045) were independently associated with 1-month mortality.

INTERPRETATION

Despite the non-specific and mild presentation of L monocytogenes-associated spontaneous bacterial peritonitis, the outcome is poor and similar to that of neurolisteriosis, and so identification of L monocytogenes in ascitic fluid samples requires urgent parenteral amoxicillin-based treatment to avoid a fatal outcome.

FUNDING

Institut Pasteur, Inserm, and French Public Health Agency.

TRANSLATION

For the French translation of the abstract see Supplementary Materials section.

Periton Diyalizi İle ilişkili Peritonitlerin İrdelenmesi

Objective: In this study, it was aimed to determine the causative microorganisms isolated in peritonitis attacks in peritoneal dialysis (PD) patients in our hospital and methicilline resistance rate in Staphlococci. Material and methods: 194 patients in the peritoneal dialysis unit of XXXXl Training and Research Hospital, Nephrology Clinic, between January 2009 and 2020, were evaluated retrospectively in terms of peritonitis development, causative microorganisms and methicillin resistance in Stapylococci, which is the most common causative agent. Results: Peritonitis attack developed in 149 out of a total of 194 patients. The causative agent has been isolated in 91 (61%) of the patients who developed peritonitis. When we look at the order of frequency among all microorganisms isolated, methicillin-susceptible Staphylococci (MHS) 59 (44.02%), methicillin-resistant Staphylococci (MRS) 28 (20.89%), Escherichia coli 12 (8.95%), Streptococcus spp 12 (8.95%), Enterobacter spp 7 (5.22%), Pseudomonas spp 4 (2.98%), diphtheroid bacilli 4 (2.98%), Klebsiella spp 2 (1.49%), Acinetobacter spp 1 (0.07%), a total of 129 bacteria, including five fungi were detected. Methicillin resistance rate was 32.18% among Staphylococci, which was found to be the most common causative agent. Conclusion: There is a need for studies with large patient groups to show the agents of peritonitis and the change in the resistance profile these microorganisms. Key words: Peritoneal Dialysis, Peritonitis, Methicillin Resistance

Chi-square automatic interaction detector decision tree analysis model: Predicting cefmetazole response in intra-abdominal infection

BACKGROUND

Cefmetazole is used as the first-line treatment for intra-abdominal infections. However, only a few studies have investigated the risk factors for cefmetazole treatment failure.

AIMS

This study aimed to develop a decision tree-based predictive model to assess the effectiveness of cefmetazole in initial intra-abdominal infection treatment to improve the clinical treatment strategies.

METHODS

This retrospective cohort study included adult patients who were unexpectedly hospitalized due to intra-abdominal infections between 2003 and 2020 and initially treated with cefmetazole. The primary outcome was clinical intra-abdominal infection improvement. The chi-square automatic interaction detector decision tree analysis was used to create a predictive model for clinical improvement after cefmetazole treatment.

RESULTS

Among 2,194 patients, 1,807 (82.4%) showed clinical improvement post-treatment; their mean age was 48.7 (standard deviation: 18.8) years, and 1,213 (55.3%) patients were men. The intra-abdomせinal infections were appendicitis (n = 1,186, 54.1%), diverticulitis (n = 334, 15.2%), and pancreatitis (n = 285, 13.0%). The chi-square automatic interaction detector decision tree analysis identified the intra-abdominal infection type, C-reactive protein level, heart rate, and body temperature as predictive factors by categorizing patients into seven groups. The area under the receiver operating characteristic curve was 0.71 (95% confidence interval: 0.68-0.73).

CONCLUSION

This predictive model is easily understandable visually and may be applied in clinical practice.

First Case Report of Sphingobium lactosutens as a Human Pathogen Causing Peritoneal Dialysis-Related Peritonitis

Novel pathogens keep evolving from time to time. In this article, we describe a rare case of the bacterium Sphingobium lactosutens causing peritoneal dialysis-related peritonitis in a patient who presented to our dialysis clinic with typical features of abdominal pain and diffuse abdominal tenderness and was successfully treated with the intraperitoneal antibiotic therapy. There were only very few cases of infections caused by Sphingobium species before. Here, we discuss the infections caused by other Sphingobium species, probable sources of infection, clinical findings, and susceptibility patterns. We also aim to create awareness about this rare bacterial pathogen and emphasize the need for more research to successfully treat and prevent future infections.

Peritoneal Dialysis Guidelines 2019 Part 1 (Position paper of the Japanese Society for Dialysis Therapy)

Approximately 10 years have passed since the Peritoneal Dialysis Guidelines were formulated in 2009. Much evidence has been reported during the succeeding years, which were not taken into consideration in the previous guidelines, e.g., the next peritoneal dialysis PD trial of encapsulating peritoneal sclerosis (EPS) in Japan, the significance of angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs), the effects of icodextrin solution, new developments in peritoneal pathology, and a new international recommendation on a proposal for exit-site management. It is essential to incorporate these new developments into the new clinical practice guidelines. Meanwhile, the process of creating such guidelines has changed dramatically worldwide and differs from the process of creating what were “clinical practice guides.” For this revision, we not only conducted systematic reviews using global standard methods but also decided to adopt a two-part structure to create a reference tool, which could be used widely by the society’s members attending a variety of patients. Through a working group consensus, it was decided that Part 1 would present conventional descriptions and Part 2 would pose clinical questions (CQs) in a systematic review format. Thus, Part 1 vastly covers PD that would satisfy the requirements of the members of the Japanese Society for Dialysis Therapy (JSDT). This article is the duplicated publication from the Japanese version of the guidelines and has been reproduced with permission from the JSDT.

Incidence and characteristics of methicillin-resistant coagulase-negative Staphylococcus aureus in peritoneal dialysis-associated peritonitis in a single center using molecular methods

PURPOSE

Peritonitis is a serious complication of peritoneal dialysis and coagulase-negative Staphylococcus (CNS) is the most frequent cause of peritoneal dialysis (PD)-infections in many centers. This study aimed to investigate the molecular epidemiology of CNS isolated from PD-peritonitis in a Brazilian single center, focusing on the genetic determinants conferring methicillin resistance.

METHODS

Bacterial strains were isolated from peritoneal fluid of patients presenting PD-peritonitis, identified by phenotypic and molecular methods, and those identified as CNS were submitted to mecA detection, SCCmec, pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST).

RESULTS

Over the 18-year period of this study (1995-2011), a total of 878 peritonitis episodes were diagnosed in this unit, 115 were caused by coagulase-negative staphylococci of which 72 by Staphylococcus epidermidis. mecA gene was detected in 55 CNS (47.8%), more frequently on the more recent years. SCCmec type III was the most frequent cassette, followed by SCCmec type IV and SCCmec type II. A diverstity of pulsotypes was observed among the S. epidermidis isolates, but five clusters (based on the 80% cutoff) were identified. Diversified sequence types (ST02, ST05, ST06, ST09, ST23, ST59 and ST371) were detected.

CONCLUSIONS

Detection of SCCmec type III among coagulase-negative Staphylococcus underscores the role of hospital environments as potential source of methicillin-resistant Staphylococcus causing peritonitis in PD patients.

Risk factors for peritonitis in patients on continuous ambulatory peritoneal dialysis who undergo colonoscopy: a retrospective multicentre study

BACKGROUND

Colonoscopy is associated with a risk of peritonitis in patients on peritoneal dialysis. However, no study has yet described the risk factors in play.

METHODS

This was a retrospective multicentre study. The medical records of patients on continuous ambulatory peritoneal dialysis (CAPD) who underwent colonoscopy from January 2003 to December 2012 were analysed. We recorded demographic characteristics, colonoscopic factors, use of prophylactic antibiotics, and development of peritonitis. Colonoscopy-related peritonitis was defined as peritonitis developing within 1 week after colonoscopy. Demographic and clinical characteristics were compared between patients who did and those who did not develop peritonitis.

RESULTS

During the study period, 236 patients on CAPD underwent colonoscopy, of whom 9 (3.8%) developed peritonitis. The rates of polypectomy/endoscopic mucosal resection were significantly higher in the peritonitis group than in the no peritonitis group (66.7 vs. 23.4%, p = 0.009). Prophylactic antibiotics were prescribed before colonoscopy in 65 patients; none developed peritonitis. No patient who developed peritonitis received prophylactic antibiotics (p = 0.067).

CONCLUSIONS

Advanced procedures including polypectomy or endoscopic mucosal resection increase colonoscopy-related peritonitis in patients on CAPD. Randomized controlled trials to investigate whether prophylactic antibiotics are needed to prevent peritonitis in all CAPD patients are warranted.

Peritonitis in Children on Chronic Peritoneal Dialysis: The Experience of a Large National Pediatric Cohort

BACKGROUND

We performed this study to evaluate the incidence, risk factors, microbiology, treatment, and outcome of peritonitis in pediatric Peritoneal dialysis (PD) patients at a nationwide prospective study.

METHODOLOGY

Patients younger than 18 years recruited in the BRAZPD II study from 2004 to 2011, who presented their first peritonitis episode, were included in the study.

RESULTS

We found 125 first episodes of peritonitis in 491 children PD patients (0.43 episodes/patient-year). Patients free of peritonitis episode constituted 75.6% in 1 year. Culture-negative episodes were very high (59.2%) and gram-positive (GP) bacteria were the most commonly found organisms (58.8%). First-generation cephalosporin was the initial choice to cover GP (40.5%) and aminoglycosides was the most prescribed antibiotics used for gram-negative agents (27.5%). Treatment failure was 26.4%. Technique failure (TF) occurred in 12.1% and peritonitis was the main cause (65.1%). Pseudomonas (p = 0.04) and negative cultures (p < 0.001) were identified as predictors of TF.

CONCLUSION

Peritonitis remains a common complication of PD in children and negative cultures and pseudomonas had a negative impact on TF.

Risk factors and outcomes of high peritonitis rate in continuous ambulatory peritoneal dialysis patients: A retrospective study

Peritonitis remains a major complication of peritoneal dialysis (PD). A high peritonitis rate (HPR) affects continuous ambulatory peritoneal dialysis (CAPD) patients' technique survival and mortality. Predictors and outcomes of HPR, rather than the first peritonitis episode, were rarely studied in the Chinese population. In this study, we examined the risk factors associated with HPR and its effects on clinical outcomes in CAPD patients.This is a single center, retrospective, observational cohort study. A total of 294 patients who developing at least 1 episode of peritonitis were followed up from March 1st, 2002, to July 31, 2014, in our PD center. Multivariate logistic regression was used to determine the factors associated with HPR, and the Cox proportional hazard model was conducted to assess the effects of HPR on clinical outcomes.During the study period of 2917.5 patient-years, 489 episodes of peritonitis were recorded, and the total peritonitis rate was 0.168 episodes per patient-year. The multivariate analysis showed that factors associated with HPR include a quick occurrence of peritonitis after CAPD initiation (shorter than 12 months), and a low serum albumin level at the start of CAPD. In the Cox proportional hazard model, HPR was a significant predictor of technique failure. There were no differences between HPR and low peritonitis rate (LPR) group for all-cause mortality. However, when the peritonitis rate was considered as a continuous variable, a positive correlation was observed between the peritonitis rate and mortality.We found the quick peritonitis occurrence after CAPD and the low serum albumin level before CAPD were strongly associated with an HPR. Also, our results verified that HPR was positively correlated with technique failure. More importantly, the increase in the peritonitis rate suggested a higher risk of all-cause mortality.These results may help to identify and target patients who are at higher risk of HPR at the start of CAPD and to take interventions to reduce peritonitis incidence and improve clinical outcomes.

Peritoneal Dialysis-Related Infection in the Older Population

With appropriate training and adequate support, it is possible to keep the peritonitis rate of elderly peritoneal dialysis (PD) patients at a highly respectable level. In general, the latest recommendations for the treatment and prevention of PD-related infections by the International Society for Peritoneal Dialysis (ISPD) are applicable to older patients. However, there are minor differences in the spectrum of causative organisms amongst elderly patients, with coagulase-negative staphylococcal species (CNSS) and Enterobacteriaceae species being more common in elderly patients. Elderly PD patients who develop peritonitis have an excessive short-term mortality, and, amongst elderly patients, a high burden of comorbid load increases the risk of relapsing episodes. In addition, technical problems, social difficulties, and concomitant comorbid diseases often have profound effects on the risk of peritonitis as well as its management.

Evidence-based medicine: An update on treatments for peritoneal dialysis-related peritonitis

Peritonitis continues to be a major complication of peritoneal dialysis (PD), and adequate treatment is crucial for a favorable outcome. There is no consensus regarding the optimal therapeutic regimen, and few prospective controlled studies have been published. The objective of this manuscript is to review the results of PD peritonitis treatment reported in narrative reviews, systematic reviews, and proportional meta-analyses. Two narrative reviews, the only existing systematic review and its update published between 1991 and 2014 were included. In addition, we reported the results of a proportional meta-analysis published by our group. Results from systematic reviews of randomized control trials (RCT) and quasi-RCT were not able to identify any optimal antimicrobial treatment, but glycopeptide regimens were more likely to achieve a complete cure than a first generation cephalosporin. Compared to urokinase, simultaneous catheter removal and replacement resulted in better outcomes. Continuous and intermittent IP antibiotic use had similar outcomes. Intraperitoneal antibiotics were superior to intravenous antibiotics in reducing treatment failure. In the proportional meta-analysis of RCTs and the case series, the resolution rate (86%) of ceftazidime plus glycopeptide as initial treatment was significantly higher than first generation cephalosporin plus aminoglycosides (66%) and glycopeptides plus aminoglycosides (75%). Other comparisons of regimens used for either initial treatment or treatment of gram-positive rods or gram-negative rods did not show statistically significant differences. The superiority of a combination of a glycopeptide and a third generation cephalosporin was also reported by a narrative review study published in 1991, which reported an 88% resolution rate.

Pasteurella species peritoneal dialysis-associated peritonitis: Household pets as a risk factor

Peritoneal dialysis (PD) is an alternative to hemodialysis that is preferable for some patients; however, is it associated with increased risk for peritonitis due to the catheter insertion in the peritoneum. A particular risk factor for peritonitis in patients undergoing PD is exposure to household pets because one of the most common causative organisms, Pasteurella multocida, is known to colonize the upper respiratory tract in the majority of cats and dogs. This review includes both a review of PD-associated peritonitis cases occuring in patients enrolled in the Manitoba Renal Program and a review of cases published in the literature. Recommendations for therapy are also described.

BACKGROUND:

Pasteurella species are Gram-negative coccobacilli that are a part of the normal oropharyngeal flora of numerous domestic animals. They have been recognized as a rare but significant cause of peritonitis in patients undergoing peritoneal dialysis (PD). A consensus about management strategies for PD-associated peritonitis caused by Pasteurella species currently does not exist.

METHODS:

The microbiological database serving the Manitoba Renal Program was searched from 1997 to 2013 for cases of Pasteurella species PD-associated peritonitis, and charts were reviewed. PubMed was searched for case reports and data were abstracted.

RESULTS:

Seven new local cases and 30 previously reported cases were analyzed. This infection is clinically similar to other forms of PD peritonitis, with household pet exposure appearing to be the strongest risk factor. Cats are the most commonly implicated pet. Direct contact between the pet and the equipment was commonly reported (25 of 37 patients) but was not necessary for infection to develop. The mean duration of treatment was 15 days. Complication rates were low, with only 11% of patients requiring PD catheter removal. There was no mortality reported.

CONCLUSION:

Pasteurella species are a rare cause of PD-associated peritonitis that can be successfully treated with a two-week course of intraperitoneal antibiotics with a high likelihood of catheter salvage.

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.

Peritoneal dialysis-related peritonitis due to coagulase-negative Staphylococcus: a review of 115 cases in a Brazilian center

BACKGROUND AND OBJECTIVES

Coagulase-negative Staphylococcus (CNS) is the most frequent cause of peritoneal dialysis (PD)-related peritonitis in many centers. This study aimed to describe clinical and microbiologic characteristics of 115 CNS episodes and to determine factors influencing the outcome.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This study reviewed the records of 115 CNS peritonitis episodes that occurred in 74 patients between 1994 and 2011 at a single university center. Peritonitis incidences were calculated for three consecutive 6-year periods (P1, 1994-1999; P2, 2000-2005; P3, 2006-2011) and annually. The production of biofilms, enzymes, and toxins was evaluated. Oxacillin resistance was evaluated based on its minimum inhibitory concentration and the presence of the mecA gene.

RESULTS

The overall incidence of CNS peritonitis was 0.15 episodes per patient per year and did not vary over time (0.12, 0.14, and 0.16 for P1, P2, and P3, respectively; P=0.21). The oxacillin resistance rate was 69.6%. Toxin and enzyme production was infrequent and 36.5% of CNS strains presented the gene encoding biofilm production. The presence of icaAD genes associated with biofilm production was predictive of relapses or repeat episodes (odds ratio [OR], 2.82; 95% confidence interval [95% CI], 1.11 to 7.19; P=0.03). Overall, 70 episodes (60.9%) resolved; oxacillin susceptibility (OR, 4.41; 95% CI, 1.48 to 13.17; P=0.01) and vancomycin use as the first treatment (OR, 22.27; 95% CI, 6.16 to 80.53; P<0.001) were the only independent predictors of resolution.

CONCLUSIONS

Oxacillin resistance and vancomycin use as the first treatment strongly influence the resolution rate in CNS peritonitis, which reinforces the validity of the International Society for Peritoneal Dialysis guidelines on monitoring bacterial resistance to define protocols for initial treatment. These results also suggest that the presence of biofilm is a potential cause of repeat peritonitis episodes.

Novel predictors of peritonitis-related outcomes in the BRAZPD cohort

INTRODUCTION

Peritonitis remains the main cause of peritoneal dialysis (PD) technique failure worldwide, despite significant reductions in infection rates observed over the past decades. Several studies have described risk factors for peritonitis, technique failure and mortality. However, there are scarce data regarding predictors of complications during and after a peritonitis episode. The aim of our study was to analyze predictors of peritonitis-related outcome in the Brazilian Peritoneal Dialysis study (BRAZPD) cohort.

METHODS

All adult incident patients recruited in the BRAZPD Study between December 2004 and October 2007, who remained at least 90 days on PD and presented their first peritonitis episode (n = 474 patients) were included in the study. The endpoints analyzed were non-resolution, death due to a peritonitis episode and long-term technique survival after a peritonitis episode.

RESULTS

In the multivariable regression, non-resolution was independently associated with older age (odds ratio (OR) 1.02; p < 0.01), collagenosis as the primary renal disease (OR 4.6; p < 0.05) and Pseudomonas spp as etiological agent (OR 2.9; p < 0.05). Patients who were transferred from APD to CAPD during peritonitis therapy presented a higher risk of non-response (OR 2.5; p < 0.05). The only factor associated with death during a peritonitis episode was older age (OR 1.04; p < 0.05). Exposure to vancomycin and male gender were the independent predictors of long-term technique failure (OR 2.2; p < 0.01).

CONCLUSION

Apart from confirming previous observations of the negative impact of older age and Pseudomonas spp peritonitis on outcomes, we observed that collagenosis may negatively impact response to treatment and exposure to vancomycin may possibly reduce long-term technique survival. It is important to emphasize that the association of vancomycin with technique failure does not prove causality. These findings shed light on new factors predicting outcome when peritonitis is diagnosed.

Peritoneal dialysis-related peritonitis with Acinetobacter baumannii: a review of seven cases

Peritonitis is still known as an important complication of continuous ambulatory peritoneal dialysis (CAPD). Multi-drug resistant (MDR) Acinetobacter baumannii is an increasing problem worldwide. Moreover, the increasing reports of carbapenem-resistant A. baumannii strains is common. Although peritoneal dialysis-related peritonitis with MDR A. baumannii is rarely reported, infection with this organism always results in serious peritonitis and increases the possibility of dropout or mortality. Here, we present 7 cases of peritonitis caused by A. baumannii species. Among those 7 cases, 2 involved MDR A. baumannii, and 1 involved a carbapenem-resistant strain. All the MDR bacterial infections failed treatment. We also review the literature about Acinetobacter peritonitis and current treatment protocols.

Pathogenic analysis of sputum from ventilator-associated pneumonia in a pediatric intensive care unit

Ventilator-associated pneumonia (VAP) is a common and sometimes fatal complication in pediatric intensive care units (PICU). The aim of our study was to characterize the distribution and drug susceptibility of the pathogens isolated from the sputum of patients with VAP in the PICU of our hospital and to provide support to the administration of antibiotics early and reasonably in the clinic. Our study was conducted between January 2007 and December 2011 at the PICU of the Children’s Hospital of Zhejiang University School of Medicine. The endotracheal aspirates were collected and transported to a microbiology laboratory within 15 min. The pathogens were routinely analyzed and identified with Vitek 60 and Kirby-Bauer disk diffusion methods. Among the 121 VAP patients, 127 pathogenic strains were isolated from sputum specimens. Gram-negative and gram-positive bacteria and fungi accounted for 64.57% (82/127), 29.92% (38/127) and 5.51% (7/127), respectively. Acinetobacter baumannii (25.61%), Escherichia coli (20.27%), Stenotrophomonas maltophilia (20.27%), Klebsiella pneumoniae (16.22%) and Pseudomonas aeruginosa (9.46%) were frequently identified isolates among gram-negative bacteria. Staphylococci were susceptible to vancomycin and linezolid. All fungi were sensitive to the antimicrobial agents. The gram-negative bacteria were more prevalent than gram-positive bacteria and fungi in VAP and demonstrated a higher drug resistance. It is important to administer antimicrobial agents early and reasonably for children with VAP. Knowledge of antibiotic resistance and the characteristics of drug resistance is important for VAP prophylaxis and treatment.

Long-term effects of peritonitis on peritoneal dialysis outcomes

PURPOSE

Prevalence of peritoneal dialysis is low in part because of the perceived high risk for complications such as peritonitis. However, in the most recent era, peritonitis incidence and its effects on patient outcomes may have diminished. The aim of this study was to analyze peritonitis incidence and its impact on patient and technique survival, as well as on the kidney transplantation rate and outcome.

METHODS

All peritoneal dialysis patients from a county hospital between year 2001 and 2011 were retrospectively included. Patients were divided into two groups with respect to peritonitis. The primary composite end-point consisted of a 3-year patient mortality or technique loss. Secondary end-points were patient survival and probability of kidney transplantation with respect to peritonitis history.

RESULTS

Among 85 study patients, there were 61 peritonitis episodes. The incidence of peritonitis was 0.339 ± 0.71 episode per patient per 12 months or one episode per 29.3 ± 22.2 patient-months. The time to peritonitis was shorter, and peritonitis was more likely in patients on continuous ambulatory peritoneal dialysis than in automated peritoneal dialysis patients. Patient and technique survival and transplantation rate were similar in the group with and without peritonitis history. The primary end-point was recorded in 35 % of patients with peritonitis history and in 54 % of those without peritonitis (p = 0.04). In a multivariate analysis, the only variable significantly associated with the primary end-point and with patient survival was patient age at start of peritoneal dialysis.

CONCLUSIONS

In contemporary peritoneal dialysis patients, timely treated peritonitis may not be associated with adverse patient and technique outcomes. The transplantation rate is unaffected by the peritonitis history. Peritoneal dialysis may be promoted as the first dialysis method in appropriate patients.