The efficacy of cuff-shaving combined with negative pressure wound therapy in refractory exit-site and tunnel infections: a single center experience.

BACKGROUND: Refractory exit-site infections (ESIs) and tunnel infections (TIs) are challenging complications for patients undergoing peritoneal dialysis (PD). This study compared the outcomes of surgical intervention, notably the cuff-shaving (CS) procedure coupled with negative-pressure wound therapy (NPWT), and conservative management strategies for patients with refractory ESI and TI. METHODS: We retrospectively reviewed patients who underwent PD at our center, focusing on the incidence and management of ESI and TI. We evaluated and compared treatment outcomes, including ESI scores, frequency of ESI and/or TI, identification of causative microorganisms, and duration of catheter survival or time until removal. RESULTS: We identified 97 episodes of catheter-related ESI and/or TI across 71 patients with an incidence rate of 0.15 episodes per patient-year. Of the 23 patients with refractory ESI and/or TI, surgical intervention was performed in 8, while 15 chose conservative management. In the one-month follow-up, patients who underwent CS combined with NPWT showed no complications such as leakage, and their local symptoms resolved completely. The mean PD catheter survival time was significantly longer in the surgical group (29.38 ± 7.25 months) than in the conservative group (7.86 ± 2.13 months). Surgical intervention demonstrated a significantly higher therapeutic efficacy and extended catheter survival. CONCLUSIONS: The combination of CS and NPWT as a surgical approach is crucial for eradicating infectious foci and significantly improving the longevity of PD catheter function. This integrated surgical strategy offers a promising solution for the management of refractory ESI and TI in patients undergoing PD.

Tunnel ultrasound can guide the use of peritoneal dialysis catheter exit site relocation by external splicing and cuff removal in refractory tunnel infection.

BACKGROUND: Peritoneal dialysis (PD) catheter related infections continue to be a major cause of morbidity and transfer to hemodialysis (HD) in PD patients. The treatment of tunnel infection (TI) could be challenging, especially when the infection involves the superficial cuff requiring the removal of the catheter. To spare the patient the loss of the catheter and the transfer to HD, several mini-invasive surgical techniques have been proposed as rescue therapy. Furthermore, nowadays, the rapid growth of digital technology has enormously increased the diagnostic sensibility of the echo signal allowing to accurately defines the extent of the infectious process along the PD catheter tunnel. METHODS: Between 1st January 2020 and 31st December 2021 seven patients who underwent exit-site relocation by external splicing and cuff removal at our institution due to refractory TI were included in the study. All patients were followed until 12 months after the procedure. As soon as TI was defined refractory to the medical therapy, an ultrasonographic examination of the catheter tunnel was performed to define the extent of the infectious episode. RESULTS: Among the 7 infectious episodes, 4 were caused by P. aeruginosa, and 3 by S. aureus. Around the superficial cuff the hypo/anechoic collections detected by ultrasounds showed a mean diameter of 3.05 ± 0.79 mm. The exit-site relocation by external splicing and cuff removal was successful in all cases (7/7, 100%). CONCLUSIONS: In our experience the use of exit site relocation by external splicing and cuff removal as rescue therapy for TI with positive ultrasounds for TI limited to superficial cuff involvement and without secondary peritonitis, yielded to promising results with a success rate of 100%. This preliminary experience underlines the paramount usefulness of tunnel echography in accurately defining the extent of TI and, consequently, guiding the choice of the therapeutical approach in refractory TI.

The tunnel infection in PD: Up in the air.

Catheter-related tunnel infection may lead to peritonitis and discontinuation of performing high-quality peritoneal dialysis (PD). Tunnel infection is commonly caused by Staphylococcus aureus. Gas-forming bacterial infection is rare in patients with PD and even exceedingly rare when such a infection spreads along the PD catheter tract. The first case of emphysematous PD catheter infection is presented here.

Peritoneal Dialysis-Associated Peritonitis Caused by Achromobacter xylosoxidans: A Case Report and Literature Review.

Achromobacter xylosoxidans is a gram-negative bacterium that is responsible for rare peritonitis associated with peritoneal dialysis (PD). We present a case of a 64-year-old woman with a medical history of end-stage renal disease undergoing PD who was admitted to the emergency department with abdominal pain and nausea. Physical examination and laboratory studies revealed peritoneal signs and laboratory abnormalities consistent with peritonitis. Intraperitoneal catheter dysfunction was identified and subsequently resolved via laparoscopy. Following a peritoneal fluid culture, A xylosoxidans was identified, leading to the initiation of intraperitoneal meropenem treatment. After an initial improvement, the patient developed an ileus and recurrent abdominal symptoms, and further peritoneal cultures remained positive for A xylosoxidans. Subsequent treatment included intravenous meropenem and vancomycin for Clostridium difficile colitis. Owing to the high likelihood of biofilm formation on the PD catheter by A xylosoxidans, the catheter was removed, and the patient transitioned to hemodialysis. Intravenous meropenem was continued for 2 weeks post-catheter removal. This case highlights the challenges in managing recurrent peritonitis in PD patients caused by multidrug-resistant A xylosoxidans. A high index of suspicion, appropriate microbiological identification, and targeted intraperitoneal and systemic antibiotic treatment, along with catheter management, are crucial in achieving a favorable outcome in such cases.

[Fungal peritoneal dialysis catheter-related exit-site infection combined with tunnel infection: A case report].

Peritoneal dialysis (PD) catheter-related infection (i.e. exit-site infection and tunnel infection) is one of the main causes of PD-related peritonitis. If it cannot be controlled effectively, it could lead to PD technique failure. Therefore, timely and effective diagnosis and treatment and active prevention so as to reduce PD catheter-related infection is an important treatment goal in PD patients. PD catheter exit-site infection (ESI) and tunnel infection can be caused by a variety of microorganisms, mainly bacteria, while fungi are very rare. Few public data can be used to guide treatment of PD catheter-related fungal infection, and there is no related report in China till now. Once fungal peritonitis occurred, the patient can only withdraw from PD treatment. Here, we report a case of fungal PD catheter ESI combined with tunnel infection which was successfully diagnosed and treated in our PD center. A 71-year-old woman came to clinic because of "PD for 5 years, secretions from exit site for 8 days and aggravation for 1 day". The patient suffered from peritonitis, ESI and tunnel infection for many times in the past 5 years, involving a variety of pathogens. Eight days before, she found white viscous discharge from exit site. The subcutaneous cuff completely came out of it and rubbed its skin. The Schaefer exit-site score was 3 points. Due to the suspected ESI 2 months before, the discharge swab for bacterial culture was positive for Pseudomonas aeruginosa, so the exit site swab for bacterial culture was done again, and gentamicin injection was applied topically once a day for empirical treatment. The exit site was evaluated one day before: The subcutaneous tunnel was significantly swollen and slightly tender at 2.5 cm away from the exit site, and with white medium amount of viscous secretions. The exit-site score increased to 4 points. Routine test of dialysis effluent was (-). The bacterial culture of the exit-site discharge was rechecked twice, and Candida parapsilosis was positive for two times, so the diagnosis of fungal PD catheter ESI combined with tunnel infection was clear. Immediately we searched for the causes of ESI and tunnel infection. We found that the patient had a suspicious history of gray toenail on the foot. The toenail smear was positive for fungi and visible hyphae. She washed feet with hands every day, and washed clothes on a low bench every day, which made the exit-site and tunnel squeezed for a long time. Based on the above causes, we gave her comprehensive treatment as follows: For ESI and tunnel fungal infections, fluco-nazole was used systemically according to the drug sensitivity results, and miconazole cream was applied to the exit-site locally. For the subcutaneous cuff that came out completely, daily iodophor disinfection was given locally. At the same time, local antifungal treatment was given to the foot. We followed up closely during treatment, evaluated the exit-site every 2-3 days, and took photos of the exit-site to dynamically observe the effect. After 14 days of treatment, the exit-site score continued to be 0-1, the bacterial culture of the exit-site was negative, the cuff culture was negative, and the tunnel B-ultrasound was normal. The patient had been followed up regularly once a month for 60 months, no ESI and tunnel infection occurred. Fungal PD catheter ESI and tunnel infection are rare complications of PD. When the standard anti-infection treatment is ineffective, the possibility of fungal infection should be considered, so as to avoid prolonged use of antibiotics, aggravating fungal infection, and even progressing to fungal peritonitis, leading to withdrawal from PD. Accurate exit-site evaluation is helpful for timely diagnosis and early treatment of ESI and tunnel infection. The exit-site discharge culture and drug sensitivity test before treatment are helpful to identify the pathogen and adjust subsequent treatment. At the same time, repeated discharge culture is required in order to exclude positive fungal culture results caused by contamination. Once fungal catheter-related infection is diagnosed, we should search for possible causes actively, subsequent targeted and comprehensive treatment plays a decisive role for the prognosis of patients.

Early identification of local infections in central venous catheters for hemodialysis: A systematic review.

BACKGROUND: The use of central venous catheters (CVC) is associated with higher morbidity and mortality, related to infectious complications, contributing to poorer clinical outcomes and increased healthcare costs. According to the literature, the incidence of local infections related to CVC for hemodialysis is highly variable. This variability is related to differences in definitions of catheter-related infections. OBJECTIVE: To identify signs and symptoms for determining local infections (exit site and tunnel tract infections) used in the literature in tunnelled and nontunnelled CVC for hemodialysis. DESIGN: Systematic review METHODS: Structured electronic searches were conducted in five electronic databases, from 1 January 2000-31 August 2022, using key words and specific vocabulary, as well as manual searches in several journals. Additionally, vascular access clinical guidelines and infection control clinical guidelines were reviewed. RESULTS: After validity analysis, we selected 40 studies and seven clinical guidelines. The definitions of exit site infection and tunnel infection used in the different studies were heterogeneous. Among the studies, seven (17,5 %) used the definitions of exit site and tunnel infection based on a clinical practice guideline. Three of the studies (7.5 %) used the Twardowski scale definition of exit site infection or a modification. The remaining 30 studies (75 %) used different combinations of signs and symptoms. CONCLUSIONS: Definitions of local CVC infections are highly heterogeneous in the revised literature. It is necessary to establish a consensus regarding the definitions of hemodialysis CVC exit site and tunnel infections. REGISTRATION: PROSPERO (CRD42022351097).

Utility of ultrasonographic examination in catheter-related infections in peritoneal dialysis: a clinical approach.

Peritoneal dialysis- (PD) related infections continue to be a major cause of morbidity and mortality in patients on renal replacement therapy via PD. However, despite the great efforts in the prevention of PD-related infectious episodes, approximately one third of technical failures are still caused by peritonitis. Recent studies support the theory that ascribes to exit-site and tunnel infections a direct role in causing peritonitis. Hence, prompt exit site infection/tunnel infection diagnosis would allow the timely start of the most appropriate treatment, thereby decreasing the potential complications and enhancing technique survival. Ultrasound examination is a simple, rapid, non-invasive and widely available procedure for tunnel evaluation in PD catheter-related infections. In case of an exit site infection, ultrasound examination has greater sensitivity in diagnosing simultaneous tunnel infection compared to the physical exam alone. This allows distinguishing the exit site infection, which will likely respond to antibiotic therapy, from infections that are likely to be refractory to medical therapy. In case of a tunnel infection, the ultrasound allows localizing the catheter portion involved in the infectious process, thus providing significant prognostic information. In addition, ultrasound performed after two weeks of antibiotic administration allows monitoring patient response to therapy. However, there is no evidence of the usefulness of ultrasound examination as a screening tool for the early diagnosis of tunnel infections in asymptomatic PD patients.

The use of mini-invasive surgical techniques to treat refractory exit-site and tunnel infections in peritoneal dialysis patients: a clinical approach.

Peritoneal dialysis-(PD) related infections continue to be a major cause of morbidity and mortality in patients on PD. Although great advances have been made in the prevention and treatment of infectious complications over the past two decades, catheter-related infections represent a significant cause of technical failure in PD. Recent studies support the role of exit-site/tunnel infections in causing peritonitis. Peritonitis secondary to tunnel infection led to catheter loss in most cases. Thus, removing the catheter when exit-site/tunnel infection is refractory to medical therapy has been recommended. This approach requires interrupting PD and, after the placement of a central venous catheter, and transferring the patient to haemodialysis. In order to continue PD, simultaneous catheter removal and replacement of the PD catheter has been suggested. Although simultaneous catheter removal and replacement avoids temporary haemodialysis, it implies the removal/reinsertion of the catheter and the immediate initiation of PD with the risk of mechanical complications, such as leakage and malfunction. Hence, several mini-invasive surgical techniques, such as curettage, cuff-shaving, removal of the superficial cuff, and partial reimplantation of the catheter, have been proposed as rescue treatments. These procedures may allow the rescue of the catheter with a success rate of 70-100%. Therefore, in case of refractory exit-site/tunnel infection, a mini-invasive surgical revision should be considered before removing the catheter.

Simultaneous replacement and removal of the peritoneal catheter is effective in patients with refractory tunnel infections sustained by S. aureus.

BACKGROUND: In tunnel infection (TI) refractory to medical therapy or in case of TI that occurs simultaneously with peritonitis, the removal of the peritoneal catheter has been proposed. This approach requires the interruption of peritoneal dialysis (PD) and the creation of a temporary vascular access. However, simultaneous removal and reinsertion of the PD catheter (SCR) represents another possible therapeutic approach. METHODS: We analysed the outcome of 20 patients (10 men and 10 women, mean age 65.5 ± 16.3 years) treated by CAPD for a mean period of 24.3 ± 14.2 months who underwent to SCR for the treatment of TI unresponsive to medical therapy or TI that occurred simultaneously with peritonitis at Fondazione Ca' Granda Ospedale Maggiore Policlinico. All the patients restarted CAPD exchanges within 24 h from catheter placement. RESULTS: SCR was successful in 80% (16/20) of the cases. In particular, SCR was effective in 100% (11/11) of the TI with or without associated peritonitis sustained by S. aureus. However, SCR failed in 57% (4/7) of TI associated with relapsing peritonitis and in one patient with TI secondary to Enterobacter. No early mechanical complications (within 3 months after SCR) occurred when CAPD was restarted. CONCLUSIONS: SCR of the PD catheter through double-purse string technique represents an effective treatment for TI without or with simultaneously peritonitis sustained by S. aureus avoiding the patient the need for temporary hemodialysis and second surgical procedure. However, SCR could be contraindicated in case of relapsing peritonitis.

High body mass index is a risk factor for transition to hemodialysis or hybrid therapy and peritoneal dialysis-related infection in Japanese patients undergoing peritoneal dialysis.

PURPOSE: Obesity may negatively impact the clinical outcomes of patients undergoing peritoneal dialysis (PD). However, the impact of obesity on PD-related outcomes remains unclear. We herein examined the association of high body mass index (BMI) with complete hemodialysis (HD) transfer, transition to HD and PD/HD hybrid therapy, peritonitis, catheter exit-site and tunnel infection (ESI/TI), and heart failure-related hospitalization. METHODS: This retrospective cohort study included 120 patients who underwent PD-catheter insertion between January 2008 and June 2018. BMI ≥ 25 kg/m2 at the time of PD-catheter insertion was defined as high BMI, and its association with outcomes was analyzed using the log-rank test and Cox proportional hazards models. RESULTS: The follow-up duration was 46.2 (23.3-75.3) months. The time until transfer to HD and hybrid therapy was significantly shorter in the high BMI group than that in the low BMI group, whereas the time until HD transfer was not significantly different between the two groups (P < 0.001 and 0.18, respectively). Peritonitis-free and ESI/TI-free survivals were significantly shorter in the high BMI group than those in the low BMI group (P = 0.006 and 0.03, respectively). After adjusting for age, sex, diabetes mellitus, and estimated glomerular filtration rate, high BMI remained a significant risk factor for transferring to HD and hybrid therapy, peritonitis, and ESI/TI (hazard ratio [HR] 2.60, P < 0.001; HR 2.08, P = 0.01; HR 2.64, P = 0.02, respectively). CONCLUSION: BMI ≥ 25 kg/m2 is a risk factor for transition to HD and hybrid therapy, peritonitis, and ESI/TI, but not for complete HD transfer in Japanese patients with PD.

Catheter Diversion Procedure With Exit-Site Renewal Promotes Peritoneal Dialysis Catheter Survival.

INTRODUCTION: Catheter-related infections such as exit site infection (ESI) and tunnel infection (TI) are major causes of peritoneal dialysis (PD) discontinuation. For ESI/TI treatment, catheter diversion procedure (CDP) with exit-site renewal for catheter salvage presents an alternative to catheter removal. Nevertheless, CDP capability of improving PD catheter survival remains unclear. METHODS: We retrospectively reviewed our hospital patients who started PD during 2001-2019 (n=148): 33 treated for ESI/TI by CDP (CDP group) and 115 treated for ESI/TI using conservative therapy or none (non-CDP group). A "virtual discontinuation group" was designated for patients in the CDP group who had received PD catheter removal instead of CDP and who had stopped PD. Kaplan-Meier analysis and log-rank test PD were used for intergroup catheter survival comparison. Associations between clinical factors and PD discontinuation or death were examined using Cox proportional hazards regression analyses. RESULTS: For patients (76% male, mean age of 61.7±13.0 years), 40 CDP were performed for 33 CDP group patients. Infection-free rates at 30 and 90 days after CDP were, respectively, 90% and 67%. The CDP group PD catheter survival rate was significantly higher than that of virtual discontinuation group (P < .01) and higher than that of the non-CDP group (P = .03). Multivariate analysis revealed independent association of serum albumin concentration (hazard ratio 0.33, 95% confidence interval 0.17-0.67), PD+HD combination therapy (hazard ratio 0.29, 95% confidence interval 0.17-0.49), and CDP (hazard ratio 0.44, 95% confidence interval 0.24-0.80) with PD discontinuation or death. CONCLUSION: Results show that CDP may improve PD catheter survival as an effective and less-invasive surgical treatment for ESI/TI to avoid withdrawal of PD.

[Mini-invasive surgical techniques for rescuing the peritoneal catheter in refractory tunnel infections].

Infections continue to be a major cause of morbidity and mortality in patients on renal replacement therapy with peritoneal dialysis (PD). Despite great efforts in the prevention and treatment of infective complications over the two past decades, catheter-related infections represent the most relevant cause of technical failure. Recent studies support the idea that exit-site/tunnel infections (ESI/TI) have a direct role in causing peritonitis. Since the episodes of peritonitis secondary to TI lead to catheter loss in up to 86% of cases, it is advised to remove the catheter when the ESI/TI does not respond to medical therapy. This approach necessarily entails the interruption of PD and, after the placement of a central venous catheter, the shift to haemodialysis (HD). In order to avoid the change of dialytic method, the simultaneous removal and replacement (SCR) of the PD catheter has also been proposed. Although SCR avoids temporary HD, it requires the removal/reinsertion of the catheter and the immediate initiation of PD, with the risk of mechanical complications such as leakage and malfunction. Several mini-invasive surgical techniques have been employed as rescue procedures: curettage, cuff-shaving, the partial reimplantation of the catheter and the removal of the superficial cuff with the creation of a new exit-site. These procedures allow to save the catheter and have a success rate of 70-100%. Therefore, in case of ESI/TI refractory to antibiotic therapy, a mini-invasive surgical revision must always be considered before removing the catheter.

The impact of the superficial cuff position on the exit site and tunnel infections in CAPD patients.

BACKGROUND: Peritoneal dialysis (PD) related infections continue to be a major cause of morbidity and mortality in patients on PD. In the last ten years, in order to reduce cuff and exit-site infections, in continuous ambulatory peritoneal dialysis (CAPD) patients, we have positioned the superficial cuff subcutaneously 4 cm instead of 2 cm internal to the exit-site. METHODS: We analysed the infective episodes occurred in 123 CAPD patients (88 men and 35 women, mean age 62.4 ± 16.8) treated for 3337 months between 1st January 2011 and 31th December 2018 at Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico. RESULTS: 31 of the 123 patients (25.2%) developed 52 episodes of exit site infection, with an incidence of 1 episode every 64.1 patient-months. The cumulative probability of remaining infection free was 80.7% at 12 months and 61.8% at 36 months. Gram-positive organism accounted for 78.7% of exit site infections. Forty-one episodes (87%) were successfully treated with medical therapy. Peritonitis incidence was 1 episode every 51.7 and 1 episode every 49.2 patient-months, in patients with or without a history of exit site infection respectively. The overall incidence of tunnel infection was 1 episode every 278.1 patient-months. CONCLUSIONS: Positioning the superficial cuff subcutaneously at least 4 cm internal to the exit-site might prevent the bacterial cuff colonization and reduce ESIs, tunnel infections and peritonitis.

Use of ultrasounds in PD catheter-related infections: indications and clinical implications / Utilizzo degli ultrasuoni nelle infezioni da catetere peritoneale: indicazioni e risvolti clinici

Peritoneal dialysis (PD) related infections continue to be a major cause of morbidity and mortality in patients undertaking renal replacement therapy with PD. Nevertheless, despite the great effort invested in the prevention of PD infective episodes, almost one third of technical failures are still caused by peritonitis. Recent studies support the idea that there is a direct role of exit-site (ESIs) and tunnel infections (TIs) in causing peritonitis. Hence, both the prompt ESI/TI diagnosis and correct prognostic hypothesis would allow the timely start of an appropriate antibiotic therapy decreasing the associated complications and preserving the PD technique. The ultrasound exam (US) is a simple, rapid, non-invasive and widely available procedure for the tunnel evaluation in PD catheter-related infections. In case of ESI, the US possesses a greater sensibility in diagnosing a simultaneous TI compared to the clinical criterions. This peculiarity allows to distinguish the ESI episodes which will be healed with antibiotic therapy from those refractories to medical therapy. In case of TI, the US permits to localize the catheter portion involved in the infectious process obtaining significant prognostic information; while the US repetition after two weeks of antibiotic allows to monitor the patient responsiveness to the therapy. There is no evidence of the US usefulness as screening tool aimed to the precocious diagnosis of TI in asymptomatic PD patients.

Curvularia infection of corneoscleral tunnel.

Corneoscleral tunnel infection is a potentially sight threatening complication of cataract surgery. Microbiological investigations are mandatory and early surgical intervention helps in achieving favourable outcomes. Fungal infection of tunnel incisions can pose a diagnostic and therapeutic challenge. We report a case of post-operative tunnel infection with curvularia. Prompt surgical intervention and intensive topical therapy helped attain a good tectonic as well as visual recovery.

Catheter-related infections in peritoneal dialysis: comparison of a single center results and the literature data.

BACKGROUND: Catheter-related infections are important causes of morbidity in patients undergoing peritoneal dialysis (PD). There are different protocols of exit site care for the prevention of catheter-related infections. The aim of this study was to evaluate the incidence of catheter-related infections and their complications in our PD center. METHODS: We performed a retrospective, observational study for all patients receiving PD in our center. We observed prevalent patients every year for 5 years. The patients performed the exit-site care three times a week, cleaning the exit site with 10% sodium hypochlorite. From 2017, update of ISPD recommendations suggests the application of antibiotic creams. We recorded the incidence rate of ESI and TI, gentamicin resistance, catheter lost, related post-ESI peritonitis and fungal infections, and we compared our results with the data in the literature. RESULTS: Prevalent patients per year were 117.6 ± 5.5. The "time at risk" was 356.46 years. The median values of TESI (tunnel and exit site infections), TI, gentamicin resistance, related post-ESI peritonitis and fungal infection rate were similar in our results and the literature data. The ESI and the catheter lost caused by infection were significantly lower in our patients. No significant adverse effects, such as skin allergy or intolerance, were reported. CONCLUSIONS: Our results confirm the utility and the safety of routinely exit site care using 10% sodium hypochlorite. This protocol resulted similar to the data reported in the literature. Our analysis of the literature highlighted the wide variation in the infection rate of ESI and TI.