Intravascular non-hemodialysis catheter-related infection: Treatment

INTRODUCTION — Issues related to treatment of catheter-related bloodstream infection (CRBSI) will be reviewed here.

Issues related to clinical manifestations, diagnosis, and prevention of intravascular catheter-related infection are discussed separately. (See "Intravascular non-hemodialysis catheter-related infection: Clinical manifestations and diagnosis" and "Routine care and maintenance of intravenous devices".)

Issues related to infection associated with hemodialysis catheters are discussed separately. (See "Tunneled hemodialysis catheter-related bloodstream infection (CRBSI): Management and prevention" and "Central venous catheters: Overview of complications and prevention in adults", section on 'Catheter-related infection'.)

Issues related to catheter infection due to Candida species are discussed further separately. (See "Management of candidemia and invasive candidiasis in adults" and "Treatment of Candida infection in neonates" and "Candidemia and invasive candidiasis in children: Management".)

UNCOMPLICATED VERSUS COMPLICATED INFECTION — Management of CRBSI often depends on whether the infection is uncomplicated or complicated.

For infections due to organisms other than Staphylococcus aureus (S. aureus), we consider uncomplicated infections to meet the following criteria:

●Catheter removed within five days of diagnosis

●Negative follow-up blood cultures within 24 to 72 hours after initial positive culture

●Defervescence within 72 hours of initial positive culture

●No symptoms or signs of metastatic infection

●No other indwelling intravascular prosthetic devices (eg, vascular grafts)

For infections due to S. aureus, an additional criterion for uncomplicated CRBSI is an echocardiogram without evidence of endocarditis [1].

MANAGEMENT OF CATHETER-RELATED BLOODSTREAM INFECTION — In general, management of CRBSI consists of catheter removal and systemic antibiotic therapy [2].

Indications for ID consultation — Infectious disease (ID) consultation should be pursued in the following circumstances:

●Infection due to Staphylococcus aureus, Pseudomonas aeruginosa, drug-resistant gram-negative bacilli, or Candida spp

●Patients who are unable to undergo catheter removal

●Patients with endovascular implant or orthopedic hardware

●Patients with complications of bloodstream infection such as infective endocarditis (IE), septic thrombophlebitis, metastatic musculoskeletal infection, mycotic aneurysm, or vascular graft infection

Empiric antibiotic therapy — The initial choice of empiric antibiotic therapy for treatment of catheter-related bloodstream infection (CRBSI) depends on the severity of illness, the risk factors for infection, and the likely pathogens [2].

The microbiology of catheter infections is discussed further separately (see "Intravascular catheter-related infection: Epidemiology, pathogenesis, and microbiology", section on 'Microbiology').

Empiric antibiotic therapy for treatment of CRBSI should be guided by Gram stain results, if available and positive for microorganisms [2]:

●For CRBSI due to gram-positive organisms, empiric therapy consists of vancomycin. In institutions with high rates of infection due to methicillin-resistant S. aureus (MRSA) isolates with vancomycin minimum inhibitory concentration ≥2 mcg/mL, an alternative agent such as daptomycin should be used [3]. Daptomycin may also be used in units with high rates of infection due to VRE. Linezolid is not an appropriate agent for empiric therapy of CRBSI [4].

Additional agents with activity against CoNS and MRSA that might be used to treat CRBSI include ceftaroline, telavancin, and dalbavancin [5]. Clinical data regarding efficacy of these agents for treatment of CRBSI are limited. (See "Infection due to coagulase-negative staphylococci: Treatment" and "Clinical approach to Staphylococcus aureus bacteremia in adults".)

●For CRBSI due to gram-negative bacilli, empiric therapy should be guided by clinical circumstances:

•In patients with neutropenia, severe burns, or hemodynamic instability, treatment with an antipseudomonal beta-lactam antibiotic is appropriate; examples include ceftazidime, cefepime, piperacillin-tazobactam, imipenem, and meropenem.

For patients with hemodynamic instability and in health care settings where local resistance suggests <90 percent susceptibility to antipseudomonal beta-lactams, administration of a second antipseudomonal agent (such as an aminoglycoside or ciprofloxacin) is appropriate while awaiting culture results; once susceptibilities are known, monotherapy may be administered [6]. An aminoglycoside should not be used as monotherapy. (See "Gram-negative bacillary bacteremia in adults" and "Pseudomonas aeruginosa bacteremia and endocarditis" and "Principles of antimicrobial therapy of Pseudomonas aeruginosa infections".)

•In the absence of neutropenia, severe burns, or hemodynamic instability, monotherapy with ceftriaxone or another agent with activity against gram-negative organisms is reasonable; empiric antipseudomonal coverage is generally not necessary. (See "Gram-negative bacillary bacteremia in adults".)

•Patients known to be colonized with drug-resistant organisms should receive empiric antibiotic therapy selected accordingly.

●Issues related to treatment of candidemia are discussed separately. (See "Management of candidemia and invasive candidiasis in adults" and "Treatment of Candida infection in neonates" and "Candidemia and invasive candidiasis in children: Management", section on 'Antifungal agents'.)

Selecting a catheter management strategy — In general, management of CRBSI consists of catheter removal and systemic antibiotic therapy [2].

If catheter removal is not feasible (eg, there is no alternative access site or sites are limited, the patient has a bleeding diathesis, patient declines removal, or quality of life issues take priority over the need for catheter reinsertion at another site), a decision regarding catheter salvage or guidewire exchange must be made. These issues are discussed below.

Removal — Catheter removal (in addition to administration of systemic antimicrobial therapy) is warranted in the following circumstances, given high likelihood of progressive infection with antibiotic therapy alone (table 1) [2,7-10]:

●Sepsis

●Hemodynamic instability

●Presence of concomitant endocarditis or evidence of metastatic infection

●Presence of suppurative thrombophlebitis

●Presence of a propagating clot

●Persistent bacteremia after 72 hours of appropriate antimicrobial therapy

●Subcutaneously tunneled central venous catheter tunnel tract infection or subcutaneous port reservoir infection

In addition, catheter removal is warranted in the setting of infection with the following pathogens, given relatively high virulence and relatively low likelihood of treatment response with antibiotic therapy alone:

●S. aureus

●P. aeruginosa

●Drug-resistant gram-negative bacilli

●Candida spp (see "Management of candidemia and invasive candidiasis in adults")

●Mycobacteria spp

In patients with CRBSI due to S. aureus, catheter retention has been associated with a low success rate; most patients eventually relapse and require removal of the catheter [8-12]. Early catheter removal (within three days of bacteremia onset) has been associated with lower relapse rates and lower rates of hematogenous complications. In a prospective study including 324 patients with CRBSI due to S. aureus, failure to pursue catheter removal was associated with increased risk for hematogenous complications (relative risk 2.28, 95% CI 1.22-4.27) [9]. Similarly, in a retrospective study including 304 episodes of CRBSI due to S. aureus, a higher relapse rate was observed among patients whose catheter was retained beyond three days after bacteremia onset than among those whose catheter was removed or exchanged within the first three days of bacteremia onset (12.7 versus 4.7 percent) [11].

In patients with CRBSI due to drug-resistant gram-negative bacteria, delayed catheter removal has been associated with increased mortality [13-15]. In a retrospective study including more than 70 patients with CRBSI due to a gram-negative organism, delayed catheter removal in the setting of drug-resistant infection was associated with increased 30-day mortality (odds ratio 6.8, 95% CI 1.8-26.6) [13].

In patients with CRBSI due to Enterococcus spp, catheter removal is preferred [2,16,17]; in patients for whom catheter removal is not readily feasible, catheter salvage may be attempted. In a retrospective study including 111 patients with CRBSI due to Enterococcus (of whom 74 percent underwent catheter removal), catheter retention was an independent predictor of mortality (odds ratio 3.3, 95% CI 1.2-9.3) [17]. In another study including 64 patients with dialysis catheters and CRBSI due to Enterococcus, catheter salvage was successful in 61 percent of cases [18]. (See 'Salvage' below.)

In patients with CRBSI due to organisms of relatively low virulence that are difficult to eradicate (such as Bacillus spp, Micrococcus spp, or Cutibacterium spp [formerly Propionibacterium spp]), catheter removal may be warranted if bacteremia persists and blood culture contamination has been ruled out (eg, based on multiple positive culture results with at least one sample drawn from a peripheral vein) [19,20]. However, catheter salvage with antibiotic lock therapy (ALT) may be feasible in some cases. (See 'Salvage' below and "Intravascular non-hemodialysis catheter-related infection: Clinical manifestations and diagnosis".)

Catheter removal based on the above pathogen-related considerations must be weighed against the clinical indication for the catheter and the risks associated with removal and replacement of a catheter at another site.

Catheter removal is not necessary for patients with unexplained fever who are hemodynamically stable in the absence of documented bloodstream infection [21-24].

The duration of antibiotic therapy following catheter removal depends on the pathogen. (See 'Catheter removed' below.)

Salvage — Catheter salvage refers to retention of the catheter while treating the CRBSI; we typically suggest antibiotic lock therapy (ALT) in addition to systemic antimicrobial therapy if catheter salvage is attempted [25-27] (see 'Antibiotic lock therapy' below). Catheter salvage should not be attempted in patients with a condition warranting catheter removal (table 1). (See 'Removal' above.)

In the absence of complications, catheter salvage is reasonable in the setting of CRBSI due to CoNS and drug-susceptible Enterobacteriaceae (eg, E. coli, Klebsiella species, Enterobacter species).

In patients with CRBSI due to Enterococcus spp, catheter removal is preferred; however, catheter salvage may be attempted in patients for whom catheter removal is not readily feasible [2,16].

Circumstances precluding catheter salvage include septic thrombophlebitis, endocarditis, metastatic musculoskeletal infection, and inability to draw back and/or flush the catheter.

For children with CRBSI, some pediatricians favor attempting catheter salvage when feasible, given greater difficulty with vascular access among children than among adults; several studies have reported successful catheter salvage among children [28-30].

The duration of therapy in the setting of catheter salvage depends on the pathogen. (See 'Catheter salvaged' below.)

Guidewire exchange — Guidewire exchange of the catheter should not be performed in patients with a condition warranting catheter removal. (See 'Removal' above.)

For situations in which catheter removal is not readily feasible, catheter salvage is preferable to guidewire exchange. (See 'Salvage' above.)

Guidewire exchange of the catheter is a management approach of last resort (eg, only in patients for whom continued access is essential and alternative vascular access is absolutely impossible due to high risk for mechanical complications or bleeding during catheter reinsertion). These caveats are important since the new catheter is inserted into a likely infected tract, and removing the old catheter will seed the tract if not yet infected. Most studies describing successful management of CRBSI via guidewire exchange have been small, uncontrolled studies [31-35].

Patients who undergo guidewire exchange should receive systemic antimicrobial therapy and ALT; the clinical approach is the same as for catheter salvage. (See 'Catheter salvaged' below.)

Subsequent management

Catheter removed

Directed systemic antibiotic therapy and duration

Coagulase-negative Staphylococcus — Issues related to catheter management for CRBSI due to CoNS are discussed above. (See 'Selecting a catheter management strategy' above.)

Antimicrobial agents for treatment of CRBSI due to staphylococci are summarized in the table (table 2). The optimal duration of antibiotic therapy for CRBSI due to CoNS is uncertain [2]; our approach is as follows:

●For patients with no endovascular implant or orthopedic hardware and uncomplicated CRBSI due to CoNS who undergo catheter removal with rapid clearance of bacteremia, we favor systemic antimicrobial therapy for five to seven days. (See 'Uncomplicated versus complicated infection' above.)

●For patients with endovascular implant or orthopedic hardware (in the absence of evidence for IE or orthopedic hardware infection) and uncomplicated CRBSI due to CoNS who undergo catheter removal with rapid clearance of bacteremia, we favor systemic antimicrobial therapy for 14 days. We extend the course empirically to account for the possibility of foreign material seeding. (See 'Uncomplicated versus complicated infection' above.)

Issues related to management of IE and orthopedic hardware infection are discussed separately. (See "Antimicrobial therapy of left-sided native valve endocarditis" and "Prosthetic valve endocarditis: Epidemiology, clinical manifestations, and diagnosis" and "Prosthetic joint infection: Treatment" and "Catheter-related septic thrombophlebitis".)

CRBSI due to Staphylococcus lugdunensis should be managed as for S. aureus (see 'Staphylococcus aureus' below). Issues related to S. lugdunensis infection are discussed further separately. (See "Staphylococcus lugdunensis".)

Staphylococcus aureus — In general, management of CRBSI due to S. aureus consists of catheter removal and systemic antibiotic therapy [2]. (See 'Selecting a catheter management strategy' above.)

Initial antibiotic therapy for treatment of CRBSI due to S. aureus consists of vancomycin, pending susceptibility data. Patients with CRBSI due to methicillin-susceptible S. aureus should be switched to nafcillin, oxacillin, or cefazolin (table 2).

For adults with uncomplicated CRBSI due to S. aureus who undergo catheter removal, we favor systemic antimicrobial therapy for 14 days [2]. In children, the duration of therapy is ≥7 days. (See 'Uncomplicated versus complicated infection' above.)

Issues related to S. aureus bacteremia are discussed further separately. (See "Clinical approach to Staphylococcus aureus bacteremia in adults" and "Staphylococcus aureus bacteremia in children: Management and outcome".)

Enterococcus — In general, management of CRBSI due to Enterococcus spp consists of catheter removal and systemic antibiotic therapy [2,16,17]. (See 'Selecting a catheter management strategy' above.)

Treatment of CRBSI due to susceptible enterococci consists of ampicillin; vancomycin should be used if the pathogen is resistant to ampicillin (table 2). In the setting of CRBSI due to ampicillin- and vancomycin-resistant enterococci, daptomycin or linezolid may be used, based on antibiotic susceptibility results. (See "Treatment of enterococcal infections", section on 'Bacteremia'.)

In the absence of endocarditis, monotherapy is reasonable. In retrospective studies of monotherapy versus combination therapy, no significant differences in outcomes have been observed [36,37].

For patients with uncomplicated CRBSI due to Enterococcus spp who undergo catheter removal, we favor systemic antimicrobial therapy for 7 to 14 days [2]. (See 'Uncomplicated versus complicated infection' above.)

Issues related to enterococcal bacteremia are discussed further separately. (See "Treatment of enterococcal infections", section on 'Bacteremia'.)

Gram-negative bacilli — Issues related to catheter management for CRBSI due to gram-negative bacilli are discussed above. (See 'Selecting a catheter management strategy' above.)

Issues related to empiric therapy are discussed above. (See 'Empiric antibiotic therapy' above.)

Once susceptibility data are available, directed therapy with a single active agent is appropriate if bacteremia has cleared within 48 hours (table 2).

For patients with uncomplicated CRBSI due to gram-negative bacilli who undergo catheter removal, we favor systemic antimicrobial therapy for 7 to 14 days [38,39]. (See 'Uncomplicated versus complicated infection' above.)

Candida — In general, management of CRBSI due to Candida species consists of catheter removal and systemic antifungal therapy [2]. (See 'Selecting a catheter management strategy' above.)

Issues related to catheter infection due to Candida species are discussed further separately. (See "Management of candidemia and invasive candidiasis in adults" and "Treatment of Candida infection in neonates" and "Candidemia and invasive candidiasis in children: Management".)

Monitoring and catheter replacement — Patients with CRBSI must be monitored closely for relapse or signs of metastatic infection. Surveillance blood cultures should be drawn following initiation of antibiotic therapy to demonstrate clearance of bacteremia.

Data are mixed on when a catheter should be replaced after removal [40-42]. Until more definitive data become available, we generally wait at least two to three days if a catheter needs to be reinserted, understanding that the outcomes are best when no catheter is reinserted. Ideally, at the time of catheter replacement, the patient should be hemodynamically stable with negative blood cultures for at least 48 to 72 hours (at least five days for detection of recurrent candidemia) and have no sequelae of bloodstream infection.

Catheter salvaged — Catheter salvage refers to retention of the catheter while treating the CRBSI; we typically suggest ALT in addition to systemic antimicrobial therapy if catheter salvage is attempted. (See 'Salvage' above.)

Directed systemic antibiotic therapy and duration

Coagulase-negative Staphylococcus — Issues related to catheter management for CRBSI due to CoNS are discussed above. (See 'Selecting a catheter management strategy' above.)

Antimicrobial agents for treatment of CRBSI due to staphylococci are summarized in the table (table 2). The optimal duration of antibiotic therapy for CRBSI due to CoNS is uncertain [2]; our approach is as follows:

●For patients with no endovascular implant or orthopedic hardware and uncomplicated CRBSI due to CoNS who are unable to undergo catheter removal, we favor systemic antimicrobial therapy and ALT for 10 to 14 days. (See 'Uncomplicated versus complicated infection' above and 'Antibiotic lock therapy' below.)

●For patients with endovascular implant or orthopedic hardware (in the absence of evidence for IE, endovascular infection, or orthopedic hardware infection) and uncomplicated CRBSI due to CoNS who are unable to undergo catheter removal, we favor systemic antimicrobial therapy and ALT for 14 to 21 days. This approach should be limited to situations in which symptoms of bacteremia were of short duration before antibiotics were started (≤2 days), with resolution of bacteremia within 48 hours after starting antibiotics; such patients should have repeat transthoracic echocardiogram before antibiotics are discontinued. If these criteria are not met and catheter removal is not feasible, we favor extending the duration of treatment to four to six weeks. (See 'Uncomplicated versus complicated infection' above and 'Antibiotic lock therapy' below.)

Issues related to management of IE and orthopedic hardware infection are discussed separately. (See "Antimicrobial therapy of left-sided native valve endocarditis" and "Prosthetic valve endocarditis: Epidemiology, clinical manifestations, and diagnosis" and "Prosthetic joint infection: Treatment" and "Catheter-related septic thrombophlebitis".)

CRBSI due to S. lugdunensis should be managed as for S. aureus (see 'Staphylococcus aureus' below). Issues related to S. lugdunensis infection are discussed further separately. (See "Staphylococcus lugdunensis".)

Staphylococcus aureus — In general, management of CRBSI due to S. aureus consists of catheter removal and systemic antibiotic therapy [2]. (See 'Selecting a catheter management strategy' above.)

Initial antibiotic therapy for treatment of CRBSI due to S. aureus consists of vancomycin, pending susceptibility data. Patients with CRBSI due to methicillin-susceptible S. aureus should be switched to nafcillin, oxacillin, or cefazolin (table 2).

For adults with uncomplicated CRBSI due to S. aureus who are unable to undergo catheter removal, we favor systemic antimicrobial therapy and ALT for 28 days [2]. In children, the duration of therapy is ≥14 days. (See 'Uncomplicated versus complicated infection' above and 'Antibiotic lock therapy' below.)

Issues related to S. aureus bacteremia are discussed further separately. (See "Clinical approach to Staphylococcus aureus bacteremia in adults" and "Staphylococcus aureus bacteremia in children: Management and outcome".)

Enterococcus — In patients with CRBSI due to Enterococcus spp, catheter removal is preferred [2,16,17]; in patients for whom catheter removal is not readily feasible, catheter salvage may be attempted. (See 'Selecting a catheter management strategy' above.)

Treatment of CRBSI due to susceptible enterococci consists of ampicillin; vancomycin should be used if the pathogen is resistant to ampicillin (table 2). In the setting of CRBSI due to ampicillin- and vancomycin-resistant enterococci, daptomycin or linezolid may be used, based on antibiotic susceptibility results. (See "Treatment of enterococcal infections", section on 'Bacteremia'.)

In the absence of endocarditis, monotherapy is reasonable. In retrospective studies of monotherapy versus combination therapy, no significant differences in outcomes have been observed [36,37].

For patients with uncomplicated CRBSI due to Enterococcus spp who are unable to undergo catheter removal, we favor systemic antimicrobial therapy and ALT for 14 days [2]. (See 'Uncomplicated versus complicated infection' above and 'Antibiotic lock therapy' below.)

Issues related to enterococcal bacteremia are discussed further separately. (See "Treatment of enterococcal infections", section on 'Bacteremia'.)

Gram-negative bacilli — Issues related to catheter management for CRBSI due to gram-negative bacilli are discussed above. (See 'Selecting a catheter management strategy' above.)

Issues related to empiric therapy are discussed above. (See 'Empiric antibiotic therapy' above.)

Once susceptibility data are available, directed therapy with a single active agent is appropriate if bacteremia has cleared within 48 hours (table 2).

For patients with uncomplicated CRBSI due to gram-negative bacilli are unable to undergo catheter removal, we favor systemic antimicrobial therapy and ALT 14 days. (See 'Uncomplicated versus complicated infection' above and 'Antibiotic lock therapy' below.)

Antibiotic lock therapy — ALT refers to instillation of a concentrated antibiotic solution into the catheter lumen with the intention of achieving a drug level high enough to kill bacteria within the biofilm of the catheter.

ALT is a useful adjunctive therapy (administered together with systemic antibiotic therapy) for treatment of CRBSI for circumstances in which the catheter cannot be removed [2,25,43-49]. It is most commonly used for management of CRBSI due to CoNS and drug-susceptible Enterobacteriaceae.

For patients on total parenteral nutrition or other continuous infusions, ALT may not be feasible because there is insufficient time for the antibiotic solution to dwell within the line. For multilumen catheters, ALT may be rotated between lumens, although this practice has not been studied formally.

Issues related to ALT are discussed further separately. (See "Lock therapy for treatment and prevention of intravascular non-hemodialysis catheter-related infection".)

Monitoring and indications for catheter removal — Patients with CRBSI must be monitored closely for relapse or signs of metastatic infection. Surveillance blood cultures should be drawn following initiation of antibiotic therapy to demonstrate clearance of bacteremia.

Laboratory monitoring should be performed as dictated by the systemic antibiotic regimen. (See "Outpatient parenteral antimicrobial therapy", section on 'Monitoring'.)

Presence of persistent symptoms and/or persistently positive blood cultures 72 hours after initiation of appropriate antibiotic therapy should prompt catheter removal. In addition, evaluation for complications of CRBSI (including suppurative thrombophlebitis, endocarditis, and metastatic foci of infection) should be pursued. (See "Intravascular non-hemodialysis catheter-related infection: Clinical manifestations and diagnosis", section on 'Complications'.)

Catheter exchanged over a guidewire — Patients who undergo guidewire exchange should receive systemic antimicrobial therapy and ALT; the clinical approach is the same as for catheter salvage. (See 'Catheter salvaged' above.)

MANAGEMENT OF CATHETER COLONIZATION — In the setting of a single positive catheter-drawn blood culture positive for coagulase-negative staphylococci or other potential skin contaminant, with concomitant negative peripheral-drawn blood cultures, the findings may be attributable to colonization of the catheter hub, rather than catheter infection. (See "Intravascular non-hemodialysis catheter-related infection: Clinical manifestations and diagnosis", section on 'Interpreting blood culture results'.)

In such circumstances, there may be increased risk for subsequent development of catheter-related bloodstream infection (CRBSI), especially if the catheter is left in place. We favor following the patient closely for clinical manifestations of CRBSI and obtaining additional peripheral percutaneous blood cultures. Alternative approaches include catheter removal (if feasible) or administration of antibiotic lock therapy (without systemic therapy). (See 'Antibiotic lock therapy' above.)

Blood cultures growing S. aureus should be considered clinically significant. (See "Intravascular non-hemodialysis catheter-related infection: Clinical manifestations and diagnosis", section on 'Interpreting blood culture results'.)

SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Venous access".)

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●Basics topic (see "Patient education: Central line infections (The Basics)")

SUMMARY AND RECOMMENDATIONS

●General management – In general, management of catheter-related bloodstream infection (CRBSI) consists of catheter removal (if feasible) and systemic antibiotic therapy. If catheter removal is not feasible (eg, there is no alternative access site or access sites are limited, the patient has a bleeding diathesis, the patient declines removal, or quality of life issues take priority over the need for catheter reinsertion at another site), a decision regarding catheter salvage or guidewire exchange must be made. (See 'Management of catheter-related bloodstream infection' above.)

●Infectious disease consultation – Infectious disease consultation should be pursued in the following circumstances (see 'Indications for ID consultation' above):

•Infection due to Staphylococcus aureus, Pseudomonas aeruginosa, drug-resistant gram-negative bacilli, or Candida spp

•Patients who are unable to undergo catheter removal

•Patients with endovascular implant or orthopedic hardware

•Patients with complications of bloodstream infection such as infective endocarditis, septic thrombophlebitis, metastatic musculoskeletal infection, mycotic aneurysm, or vascular graft infection

●Indications for catheter removal – We suggest catheter removal (in addition to administration of systemic antimicrobial therapy) for circumstances in which the likelihood of progressive infection is high with antibiotic therapy alone (Grade 2C). These include (table 1) (see 'Removal' above):

•Infection due to S. aureus, P. aeruginosa, drug-resistant gram-negative bacilli, Candida spp, or mycobacteria spp

•Sepsis

•Hemodynamic instability

•Presence of concomitant endocarditis or evidence of metastatic infection

•Presence of suppurative thrombophlebitis

•Presence of a propagating clot

•Persistent bacteremia after 72 hours of appropriate antimicrobial therapy

•Subcutaneously tunneled central venous catheter tunnel tract infection or subcutaneous port reservoir infection

●Catheter salvage – Catheter salvage refers to retention of the catheter while treating the CRBSI. For patients with CRBSI in whom a decision is made to salvage the catheter, we suggest treatment with systemic antibiotics in conjunction with antibiotic lock treatment (ALT), rather than systemic antibiotics alone (Grade 2C). This approach should not be attempted in patients with a condition warranting catheter removal. In the absence of complications, catheter salvage is reasonable in the setting of CRBSI due to coagulase-negative staphylococci (CoNS) and drug-susceptible Enterobacteriaceae. In patients with CRBSI due to Enterococcus spp, catheter removal is preferred; however, catheter salvage may be attempted in patients for whom catheter removal is not readily feasible. (See 'Salvage' above and 'Antibiotic lock therapy' above and "Lock therapy for treatment and prevention of intravascular non-hemodialysis catheter-related infection".)

●For patients with CRBSI due to gram-positive organisms, empiric therapy consists of vancomycin. For patients with CRBSI due to gram-negative organisms, empiric therapy should be guided by clinical circumstances. For patients with neutropenia, severe burns, or hemodynamic instability, an antipseudomonal beta-lactam antibiotic is appropriate. For patients with hemodynamic instability and in health care settings where local resistance suggests <90 percent susceptibility to antipseudomonal beta-lactams, empiric administration of an additional antipseudomonal agent (such as an aminoglycoside or ciprofloxacin) is appropriate. In the absence of above factors, empiric antipseudomonal coverage is generally not necessary. Once identification and susceptibility data are available, treatment should be narrowed to a single targeted agent. (See 'Empiric antibiotic therapy' above.)

●Antimicrobial selection and duration – Antimicrobial agents for treatment of staphylococci, enterococci, Enterobacteriaceae, and Pseudomonas are summarized in the table (table 2). The duration of therapy depends on the pathogen and on whether the catheter was removed, as described in the sections above. Patients with CRBSI must be monitored closely for relapse or signs of metastatic infection. Surveillance blood cultures should be drawn following initiation of antibiotic therapy to demonstrate clearance of bacteremia. (See 'Subsequent management' above.)

●Timing of catheter replacement – For patients who undergo catheter removal, antibiotic therapy should be administered for at least two to three days prior to catheter replacement. At the time of catheter replacement, the patient should be hemodynamically stable with negative blood cultures for at least 48 to 72 hours (at least five days for detection of recurrent candidemia) and no sequelae of bloodstream infection. (See 'Monitoring and catheter replacement' above.)

●Follow-up for catheter salvage – For patients managed with attempted catheter salvage, presence of persistent symptoms and/or persistently positive blood cultures 72 hours after initiation of appropriate antibiotic therapy should prompt catheter removal. In addition, evaluation for complications of CRBSI (including suppurative thrombophlebitis, endocarditis, and metastatic foci of infection) should be pursued. (See 'Monitoring and indications for catheter removal' above.)

●Single positive blood culture – In the setting of a single positive catheter-drawn blood culture positive for CoNS or other potential skin contaminant, with concomitant negative peripheral-drawn blood cultures, the findings may be attributable to colonization of the catheter hub, rather than catheter infection. In such circumstances, there may be increased risk for subsequent development of CRBSI, especially if the catheter is left in place. We favor following the patient closely for clinical manifestations of CRBSI and obtaining additional peripheral percutaneous blood cultures. Alternative approaches include catheter removal (if feasible) or administration of ALT (without systemic therapy). (See 'Management of catheter colonization' above.)

ACKNOWLEDGMENT — The UpToDate editorial staff acknowledges Jeffrey Band, MD, FACP, FIDSA who contributed to an earlier version of this topic review.