Management of bacteremia associated with tunneled-cuffed hemodialysis catheters

The dominant problem associated with the use of tunneled-cuffed catheters is infection. When this occurs, two issues must be addressed: treatment of the infection and management of the catheter. The purpose of this 2-yr study was to report the results of a prospective observational series in which catheter management was based on the clinical picture presented by the patient. Data were collected on patients with catheter-related bacteremia (CRB) dealt with in one of three ways: (1) minimal symptoms with a normal-appearing tunnel and exit site (exchange over guidewire within 48 h of antibiotic initiation [Xchng group], 49 cases); (2) minimal symptoms but with tunnel or exit site infection (exchange over a guidewire with creation of a new tunnel [Nutunl group], 28 cases); and (3) severe clinical symptoms (catheter removal with delayed replacement after defervescence [Delay group], 37 cases). All cases were treated immediately with empiric antibiotics followed by 3 wk of antibiotic therapy based on culture sensitivities. A cure was defined as a 45-d symptom-free interval after antibiotic therapy was complete. A cure rate total of 87.8% for the Xchng group, 75% for the Nutunl group, and 86.5% for the Delay group was seen for the 114 episodes of CRB. It is concluded that in selected patients, catheter exchange over a guidewire within 48 h of antibiotic initiation followed by 3 wk of specific antibiotic therapy is a viable treatment option. Additionally, replacing the catheter in patients presenting with severe symptoms of sepsis as soon as they have defervesced is a reasonable approach to therapy.     

Prevention and management of catheter-related infection in hemodialysis patients

Central venous catheter-related infections have been associated with high morbidity, mortality, and costs. Catheter use in chronic hemodialysis patients has been recognized as distinct from other patient populations who require central venous access, leading to recent adaptations in guidelines-recommended diagnosis for catheter-related bacteremia (CRB). This review will discuss the epidemiology and pathogenesis of hemodialysis CRB, in addition to a focus on interventions that have favorably affected CRB outcomes. These include: (1) the use of prophylactic topical antimicrobial ointments at the catheter exit site, (2) the use of prophylactic catheter locking solutions for the prevention of CRB, (3) strategies for management of the catheter in CRB, and (4) the use of vascular access managers and quality initiative programs.     

Clinical management of dialysis catheter-related bacteremia with concurrent exit-site infection

Dialysis catheter-related bacteremia (CRB) can frequently be treated with systemic antibiotics, in conjunction with an antibiotic lock, in an attempt to salvage the catheter. It is unknown whether CRB associated with an exit-site infection can be treated with such an approach. We retrospectively queried a prospective, computerized vascular access database, and identified 1436 episodes of CRB, of which 64 cases had a concurrent exit site. The frequency of concurrent exit-site infection was 9.6% with Staphylococcus epidermidis, 6.1% with Staphylococcus aureus, and only 0.7% with Gram negative CRB (p < 0.001 for Staphylococcus vs. Gram negative rods). Five serious complications (four major sepses and one endocarditis) occurred in 24 patients with S. aureus infection, but none in 32 episodes of S. epidermidis infection (p = 0.01). Catheter survival was significantly shorter in patients with S. aureus infections. The median catheter survival (without infection or dysfunction) was 14 days with S. aureus vs. 30 days with S. epidermidis infection (p = 0.035). In conclusion, concurrent exit-site infection is seen most commonly in association with Staphylococcal CRB. When the infecting organism is S. epidermidis, attempted salvage with systemic antibiotics and an antibiotic lock is reasonable. However, prompt catheter removal is indicated when the pathogen is S. aureus.     

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.     

Use of prophylactic topical or intraluminal antibiotics for hemodialysis catheters

This Practice Point commentary discusses the findings and limitations of a meta-analysis that evaluated the use of prophylactic antibiotics for hemodialysis catheters. Use of prophylactic topical antibiotics at the catheter exit site was associated with a significant reduction in catheter-related bacteremia, exit-site infections, catheter removals due to secondary complications, hospitalizations for infection, and patient mortality. Use of prophylactic intraluminal antibiotic instillation was associated with a significantly reduced risk of catheter-related bacteremia and need for catheter removal. This commentary highlights the issues that should be considered when interpreting and generalizing these results, including the variability of antibiotic type and catheter type (nontunneled vs tunneled), the use of co-interventions in the various trials, and potential publication bias. The known benefits of prophylactic antibiotic use in patients with hemodialysis catheters are strongly supported by this meta-analysis.     

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.     

Chlorhexidine-based antiseptic solutions effectively reduce catheter-related bacteremia

The aim of this retrospective study was to investigate if the application of chlorhexidine-based solutions (ChloraPrep®) to the exit site and the hub of long-term hemodialysis catheters could prevent catheter-related bacteremia (CRB) and prolong catheter survival when compared with povidone–iodine solutions. There were 20,784 catheter days observed. Povidone–iodine solutions (Betadine®) were used in the first half of the study and ChloraPrep® was used in the second half for all the patients. Both groups received chlorhexidine-impregnated dressings at the exit sites. The use of Chloraprep® significantly decreased the incidence of CRB (1.0 vs 2.2/1,000 catheter days, respectively, P?=?0.0415), and hospitalization due to CRB (1.8 days vs 4.1 days/1,000 catheter days, respectively, P?=?0.0416). The incidence of exit site infection was similar for the two groups. Both the period of overall catheter survival (207.6 days vs 161.1 days, P?=?0.0535) and that of infection-free catheter survival (122.0 days vs 106.9 days, P?=?0.1100) tended to be longer for the catheters cleansed with ChloraPrep®, with no statistical significance. In conclusion, chlorhexidine-based solutions are more effective for the prevention of CRB than povidone–iodine solutions. This positive impact cannot be explained by decreased number of exit site infections. This study supports the notion that the catheter hub is the entry site for CRB.     

We Avoid Antibiotic Lock Solutions due to Fear of Antibiotic Resistance

Hemodialysis catheter‐related bacteremia (CRB) is the most common complication associated with catheter use in dialysis patients and portends a high morbidity and mortality. Current CDC and KDIGO guidelines recommend treating CRBs with systemic antibiotics in conjunction with catheter replacement, although the latter has limitations. Antibiotic lock solutions (ABLs) are very effective in both prevention and treatment of CRBs in hemodialysis patients and may be a preferred alternative to catheter replacement especially in patients where catheter salvage is a priority. Previous smaller observational studies have raised concerns of a potential increase in antibiotic resistance associated with the widespread use of ABLs. Review of the recent literature does not support this claim.     

Corynebacterium striatum peritoneal dialysis catheter exit site infection

BACKGROUND: Regarded as normal flora of the human skin and mucus membranes, non-diphtheria corynebacteria are frequently dismissed as contaminants or harmless colonizers. Recently, the pathogenic potential of C. striatum has been realized in immunocompromised patients with indwelling medical devices and previous antibiotic exposure. OBJECTIVE: We report here the diagnosis, treatment and clinical outcome of a peritoneal dialysis patient with a C. striatum infection of the catheter exit site. The aim is to present important features to assist in identifying clinically significant infections and provide guidelines for treatment. RESULTS: An immunocompromised patient with previous antimicrobial exposure developed an acute dialysis catheter exit site infection. C. striatum was isolated in pure growth. After initial treatment failure with oral antibiotics and intensified wound care, a satisfactory outcome was ultimately achieved without relapse or loss of the catheter with a 1-month course of vancomycin, 1 g intravenously, administered at 5-day intervals. CONCLUSIONS: The virulent capacity of Corynebacterium species should not be underestimated, particularly in high-risk patients. The presence of clinical signs of infection with isolation of the organism in pure culture and the presence of Gram-positive rods on direct Gram stain, especially in association with a leukocyte reaction, supports a cause and effect relationship. Because corynebacteria may be multiresistant, susceptibility testing should be performed on clinically significant isolates. Initial antibiotic selection is influenced by the severity of the infection, however, current experience favors vancomycin in significant infections.     

Nontuberculous mycobacterial exit-site infection and abscess in a peritoneal dialysis patient

Nontuberculous mycobacterial infections of peritoneal dialysis catheter exit sites have rarely been reported in patients on peritoneal dialysis. We report here a case of Mycobacterium abscessus exit site infection with abdominal wall abscess formation in an adolescent on peritoneal dialysis, which required long-term antibiotic therapy, peritoneal dialysis catheter removal, and surgical debridement of the abscess. Nontuberculous mycobacteria should be considered as a possible causative organism for an exit site infection that fails to respond to usual antibiotic therapy. Nontuberculous mycobacterial exit site infections may require peritoneal dialysis catheter removal and surgical debridement.     

Antibiotic Lock for Treatment of Tunneled Hemodialysis Catheter Bacteremia

Catheter‐related bacteremia is a major cause of morbidity and mortality among catheter‐dependent hemodialysis patients. Microorganism biofilm matrix formation in the catheter is the pathogenic process of this entity. Administration of systemic antibiotics and removal of the offending catheter is the most logical treatment. This article discusses an alternative option, instillation of an antibiotic‐lock solution into the lumen of the catheter plus systemic antibiotic therapy. Recent studies suggest that this strategy could treat the infection and salvage the catheter, thus avoiding the need for further interventional procedures including but not limited to the removal of the catheter, placement of a temporary catheter, and finally placement of a new permanent catheter. The implementation of this effective approach will reduce morbidity and possibly reduce the cost and interventions associated with it.     

Antibiotic lock technique reduces the incidence of temporary catheter-related infections

BACKGROUND: In the hemodialytic population, infections are the second leading cause of death; access infections account for a large proportion of this mortality. The antibiotic lock technique has been applied to infected tunneled catheters as rescue or prophylaxis medication to reduce infection rates. In addition, application of topical antibiotic ointments to tunneled and non-tunneled catheters also prevents exit site infections. METHODS: 17 patients with 25 catheters participated in our study from March 2004 - February 2005. The catheter lock comprised of mixed cefazolin (5 mg/dl) with heparin (2,500 IU/ml) and mupirocin was topically applied to the area (2 x 2 cm) surrounding the catheter exit site. RESULTS: The catheter infection rate was reduced from 12.7 times/1,000 catheter days to 5.02 times/1,000 catheter days in patients with jugular vein catheters. The total catheter-related infection rate was 14.9 times/1,000 catheter days in the control group and 4.1 times/1,000 catheter days in the study group. The reduction in catheter infections was more evident in a subgroup of non-diabetic patients, and in those with femoral catheters. CONCLUSION: The use of antibiotic lock and topical antibiotics significantly reduces the incidence of temporary catheter-related infections, especially in non-diabetic patients and in those with femoral catheters.     

Prevention of catheter-related bacteremia in children on hemodialysis: time for action

This editorial commentary discusses the strategies for prevention of catheter-related bacteremia (CRB) in children on hemodialysis, which is associated with high morbidity and the increase of hospital cost. There is evidence that the use of arteriovenous fistulae in children on hemodialysis is associated with lower infection rates. Therefore, the use of catheters in these patients should be decreased by improving arteriovenous fistulae use rates or by increasing peritoneal dialysis patient recruitment. However, despite the wide adoption of such policies, hemodialysis catheters are still being used in a significant number of cases. For these patients, implementation of effective strategies for preventing contamination of the catheter hub should be a priority. The appropriate recording and evaluation of CRB rates are important for assessing preventive policies. In addition, the successful management of a CRB is essential for preventing recurrence of bacteremia. Recently it was documented in a number of randomized clinical trials that antimicrobial lock solutions were effective for preventing CRB. It is suggested that the use of antimicrobial locks should be considered in children who are at high risk of developing CRB, with caution for their long-term use, because of the possibility of bacterial resistance. Now is the time for action, and all preventive steps should be performed simultaneously to minimize the risk of CRB.     

Central venous dialysis catheters: catheter-associated infection

Tunneled dialysis catheters (TDC) are extensively used for long-term venous hemodialysis access and their use is frequently associated with infectious complications. Catheter-related bacteremia (CRB) is the most common and important infection associated with TDC use and may be caused by a wide variety of Gram-positive or Gram-negative organisms. Prevention of CRB can be difficult despite use of rigorous infection-control techniques for catheter insertion and access. A number of antibacterial catheter-packing solutions hold promise for reduction of CRB. Treatment of CRB with antibiotics alone yields poor results and may increase the risk for other infectious complications, especially endocarditis. In selected cases where initial infection control can be achieved with antibiotics, guidewire exchange of the TDC results in cure rates equivalent to those of TDC removal and subsequent replacement. Dialysis programs should monitor TDC infections with attention to incidence, bacteriology, and outcomes.     

Predictors and outcome of catheter-related bacteremia in children on chronic hemodialysis

Tunneled central venous catheters are often used in children on chronic hemodialysis. This study was done to evaluate the spectrum of catheter-related bacteremia (CRB) and to determine predictors of recurrent CRB in children on hemodialysis. Chart review was performed in 59 children from a pediatric dialysis unit with chronic, tunneled, cuffed hemodialysis catheters between January 1999 and December 2003. CRB was diagnosed in 48 of 59 (81%) patients. The incidence of CRB was 4.8/1,000 catheter days. Overall catheter survival (290±216 days) was significantly longer than infection-free catheter survival (210±167 days, p<0.05). Organisms isolated were gram-positive in 67%, gram-negative in 14%, and polymicrobial in 19%. Systemic antibiotics cleared CRB in 34% and an additional 23% cleared with the inclusion of antibiotic-heparin locks; 43% required catheter exchange. There was a significant likelihood of early catheter exchange with polymicrobial CRB (p<0.01). Catheter loss occurred from infection in 63%. Risk factors for CRB included young age (<10 years) and presence of human immunodeficiency virus (HIV) infection. Patients with >2 initial positive blood cultures (p<0.0001) had a significantly higher rate of recurrence after 6 weeks of initial treatment. In conclusion, CRB remains a major determinant of catheter loss. However, overall catheter survival is longer than infection-free catheter survival, suggesting that systemic antibiotics with antibiotic-heparin locks should be the initial step in the management of CRB and this approach may salvage some catheters.     

Avoiding trouble down the line: the management and prevention of hemodialysis catheter-related infections

Over the last 2 decades, hemodialysis catheter use has increased. Annually, approximately 30% of patients using a central venous catheter (CVC) experience a septic or bacteremic episode and are subsequently at risk of its associated long-term complications and mortality. Because of the serious clinical and financial impact of hemodialysis catheter-related bacteremias (HCRIs), standardized, validated definitions based on the hemodialysis patient population are necessary in order to better diagnose, monitor, and report HCRI for patient quality assurance and research purposes. The pathophysiology of HCRI involves a complex interaction between a triad that consists of the host patient, the infecting microorganism, and the vehicle catheter. Although the microorganism contribution in the pathogenesis of HCRI is likely most important, certain patient and catheter-related characteristics may be more amenable to manipulation. The key to managing HCRI is on prophylaxis against the initial microorganism catheter adherence and subsequent biofilm development. General and specific prophylactic maneuvers directed at both an intravascular and extraluminal route of microorganism entry are discussed including antibiotic- and silver-impregnated catheters and dressings, subcutaneous access devices, and topical prophylaxis at the exit site. In addition to systemic antibiotic use, the 3 methods of HRCI treatment using catheter salvage, guidewire exchange, and concurrent antibiotic lock are compared. The outcome and complications of HCRI may be serious and highlight the importance of careful, continual infection surveillance. Although the use of a multidisciplinary hemodialysis infection control team is desirable, staffing education and physician feedback have been shown to improve adherence to infection control guidelines and reduce HCRI.     

Outcome and complications of temporary haemodialysis catheters.

BACKGROUND: The use of temporary haemodialysis catheters is often complicated by mechanical or infectious complications. Risk factors for these complications and optimal management to reduce their incidence are largely unknown. METHODS: We conducted a prospective study of 105 haemodialysis catheters (79 subclavian, 26 jugular) inserted in 52 patients in order to identify patient outcomes and to analyse the effect of patient and catheter factors on the incidence of infectious complications by multivariate analysis. RESULTS: Fifty-nine per cent of catheters were removed for a suspected complication. Catheter-related bacteraemia (CRB) was diagnosed in 17 catheters (16%), giving a bacteraemia rate of 6.5 episodes per 1000 catheter days. Subgroup analysis revealed a higher risk of CRB with the use of the internal jugular compared with the subclavian site (hazard ratio 3.97, P=0.02). Age, diabetes or catheter exchange over a guidewire did not alter the risk of CRB. The cumulative risk of developing CRB increased in a linear fashion as the period of catheterization increased. Exit-site infection was the cause for removal in eight catheters (8%). Although the number of exit-site infections was small, the risk of exit-site infection was increased in diabetic patients (hazard ratio 10, P=0.03) and the jugular position (hazard ratio 6.5, P=0.01) but not by age or catheter exchange over a guidewire. Staphylococcus aureus and coagulase-negative staphylococcus accounted for all proven episodes of CRB. Exit-site infection was associated with a mixture of Gram-positive and Gram-negative organisms. CONCLUSIONS: Temporary haemodialysis catheters have a high failure rate associated with a significant rate of complications. Use of the internal jugular site is associated with a significantly higher risk of infectious complications and methods to reduce this risk should be considered if this site is used.     

Persistent and recurrent skin infection with small-colony variant methicillin-resistant Staphylococcus aureus

S. aureus is one of the problematic bacteria, capable to develop resistance mechanisms to all antibiotics that the bacteria are naturally susceptible. A particular phenotypic mechanism, especially against the antibiotics that repressed the synthesis of the cellular wall and aminoglycosides, was evidenced in subpopulations that grows in small-colonies and represents auxotrophic mutants for hemin, menadione or thymidine. This type of strains has been isolated most frequently from patients with osteomyelitis, septic arthritis or pulmonary infections after a long period of antibiotic treatment. The authors present the case of a patient with persistent and recurrent staphylococcal infection of the peritoneal dialysis exit site, treated with different antibiotics (ciprofloxacin, vancomycin, amoxicillin and clavulanic acid, cephalexin) from witch has been isolated a small-colony strain of methicillin-resistant S. aureus. Therapeutic failure can be explain by the slow multiplication of this strain in vivo, persistence into phagocytes and the protection offered by biofilm from the surface of the catheter. Bacteriologic diagnosis in these cases is difficult because of the culture, biochemical and susceptibility testing particularities of these strains. All these may lead failure to identification small colony variants of S. aureus and mis-evaluation of the frequency of infection with these strains in patients with long-term antibiotherapy.     

Bacterial biofilms in patients with indwelling urinary catheters

Bacteria have a basic survival strategy: to colonize surfaces and grow as biofilm communities embedded in a gel-like polysaccharide matrix. The catheterized urinary tract provides ideal conditions for the development of enormous biofilm populations. Many bacterial species colonize indwelling catheters as biofilms, inducing complications in patients' care. The most troublesome complications are the crystalline biofilms that can occlude the catheter lumen and trigger episodes of pyelonephritis and septicemia. The crystalline biofilms result from infection by urease-producing bacteria, particularly Proteus mirabilis. Urease raises the urinary pH and drives the formation of calcium phosphate and magnesium phosphate crystals in the biofilm. All types of catheter are vulnerable to encrustation by these biofilms, and clinical prevention strategies are clearly needed, as bacteria growing in the biofilm mode are resistant to antibiotics. Evidence indicates that treatment of symptomatic, catheter-associated urinary tract infection is more effective if biofilm-laden catheters are changed before antibiotic treatment is initiated. Infection with P. mirabilis exposes the many faults of currently available catheters, and plenty of scope exists for improvement in both their design and production; manufacturers should take up the challenge to improve patient outcomes.     

Xanthomonas maltophilia infection in chronic peritoneal dialysis patients

Xanthomonas maltophilia infection has only been occasionally reported in patients receiving chronic peritoneal dialysis. We describe four cases of Xanthomonas maltophilia infection associated with chronic peritoneal dialysis. Two patients presented with peritonitis and two with exit site infection. All patients were diabetics, who immediately prior to the study had not received antibiotic therapy. Failure to respond to multiple antibiotic therapy resulted in catheter removal in both patients with peritonitis. In those patients with only exit site infections, dialysis could be continued following antibiotic therapy and catheter replacement in one. Catheter loss in our patients was directly attributed to peritonitis with Xanthomonas maltophilia infection.