Catheter-related septic thrombophlebitis

INTRODUCTION — Catheter-related septic thrombophlebitis is a complication of catheter-related bloodstream infection (CRBSI). This usually involves inflammation and suppuration within the wall of the vein, infected thrombus within the lumen, surrounding soft tissue inflammation, and persistent bacteremia [1].

The epidemiology, microbiology, clinical manifestations, diagnosis, and treatment of catheter-related septic thrombophlebitis will be reviewed here.

Issues related to the epidemiology, pathogenesis, microbiology, clinical manifestations, diagnosis, treatment and prevention of CRBSI are discussed separately. (See "Intravascular catheter-related infection: Epidemiology, pathogenesis, and microbiology" and "Intravascular non-hemodialysis catheter-related infection: Clinical manifestations and diagnosis" and "Intravascular non-hemodialysis catheter-related infection: Treatment" and "Routine care and maintenance of intravenous devices".)

EPIDEMIOLOGY — Catheter-related septic thrombophlebitis is a relatively uncommon complication of catheter-related bloodstream infection (CRBSI); in one series including 102 episodes of CRBSI, suppurative thrombophlebitis was observed in 7 percent of cases [2].

Risk factors for catheter-related septic thrombophlebitis include burns [3], cut-downs in burn patients for vein access [4], glucocorticoid use [5], and injection drug use [6]. Burn patients may be at particular risk due to a variety of factors (eg, altered skin flora, impairment of local defense due to loss of skin integrity) [3]. (See "Burn wound infection and sepsis".)

MICROBIOLOGY — The microbiology of catheter-related septic thrombophlebitis reflects the microbiology of catheter-related bloodstream infection. The most common cause is Staphylococcus aureus [6,7]; streptococci and Enterobacteriaceae are also well-described pathogens [6,7]. Burn patients may have polymicrobial infection [8]. (See "Intravascular catheter-related infection: Epidemiology, pathogenesis, and microbiology", section on 'Microbiology'.)

CLINICAL MANIFESTATIONS AND DIAGNOSIS — Catheter-related septic thrombophlebitis should be suspected in patients with catheter-related bloodstream infection and persistent bacteremia after 72 hours of appropriate antibiotic therapy. Additional clinical manifestations may include fever, erythema, tenderness, a palpable cord, and purulent drainage at the site of the involved vessel [6-8]. Complications of septic thrombophlebitis include intravascular abscess, septic pulmonary emboli, and secondary pneumonia; these may also be presenting manifestations [9-12].

The diagnosis of catheter-related septic thrombophlebitis may be established based on radiographic evidence of thrombosis together with microbiology data. The presence of venous thrombosis may be established via duplex ultrasonography, contrast venography, or computed tomography scan with contrast [13]; the microbiologic diagnosis can be made based on culture of blood or purulent material expressed or surgically drained from the site. (See "Intravascular non-hemodialysis catheter-related infection: Clinical manifestations and diagnosis", section on 'Diagnosis'.)

DIFFERENTIAL DIAGNOSIS — Catheter-related septic thrombophlebitis is a complication of catheter-related bloodstream infection (CRBSI); the differential diagnosis of CRBSI is discussed separately. (See "Intravascular non-hemodialysis catheter-related infection: Clinical manifestations and diagnosis", section on 'Differential diagnosis'.)

MANAGEMENT — Principles of management include removing the focus of infection (eg, catheter removal), prompt administration of intravenous antibiotics, and consideration regarding the need for anticoagulation or surgical intervention.

Catheter removal — Catheter removal is warranted in the setting of septic thrombophlebitis, given high likelihood of progressive infection with antibiotic therapy alone.

In a retrospective study including 128 patients with S. aureus catheter-related septic thrombosis, central venous catheter removal or exchange within 48 hours of bacteremia onset was the only intervention with an association trend for fever and microbiologic resolution within 72 hours; these interventions were performed in 70 percent of patients with treatment success and 51 percent of patients with treatment failure [13].

Issues related to catheter removal for patients with catheter-related bloodstream infection (CRBSI) are discussed further separately. (See "Intravascular non-hemodialysis catheter-related infection: Treatment", section on 'Selecting a catheter management strategy'.)

Antibiotic therapy — The approach to selection of empiric and directed antibiotic therapy for catheter-related septic thrombophlebitis is the same as for treatment of CRBSI (table 1). Antibiotics should be tailored to culture and susceptibility data when available. (See "Intravascular non-hemodialysis catheter-related infection: Treatment".)

After 48 to 72 hours of antibiotic therapy, we repeat duplex ultrasonography to evaluate for thrombus extension. Considerations regarding anticoagulation are discussed below. (See 'Role of anticoagulation' below.)

The optimal duration of antibiotic therapy for septic thrombophlebitis is uncertain. Given infection involving the vessel wall, we favor continuation of parenteral antimicrobial therapy for four weeks (rather than shorter durations as used for treatment of CRBSI in the absence of thrombus).

This approach is supported by a retrospective study including 128 patients with cancer and catheter-related septic thrombophlebitis due to S. aureus; higher all-cause mortality was observed among patients who received less than 28 days of therapy (31 versus 5 percent) [13].

Role of anticoagulation — The benefit of anticoagulation for management of catheter-related septic thrombophlebitis is uncertain; data are limited to retrospective studies and case reports [13].

In general, we suggest not treating most patients with anticoagulation. In most cases, the major factors associated with induction of vascular inflammation and clotting are addressed by catheter removal and antibiotic administration.

We pursue anticoagulation in the setting of persistent manifestations of infection (such as fever, hemodynamic instability, bacteremia) after 48 to 72 hours of appropriate antimicrobial therapy or duplex ultrasonography evidence of thrombus extension despite appropriate antibiotic therapy.

Thrombolysis in individual case reports has been described [14], but this modality of therapy is rarely considered and is not recommended by the author.

Role of surgery — In general, surgical intervention should be reserved for patients with persistent manifestations of infection despite appropriate antimicrobial therapy and anticoagulation [6,15,16].

Potential surgical interventions include incision and drainage or excision of the affected vein and its tributaries [4,7,17]. Incision and drainage alone may be inadequate since it does not remove the septic focus and recurrent bacteremia can occur [7,18]. In one series including 24 cases of infected cut-downs among burn patients, 7 of 10 treated surgically survived; for 13 of the remaining 14, the diagnosis was only made at autopsy [4].

SUMMARY AND RECOMMENDATIONS

●Pathophysiology and risk factors – Catheter-related septic thrombophlebitis is a relatively uncommon complication of catheter-related bloodstream infection (CRBSI). It typically involves inflammation and suppuration within the wall of the vein, infected thrombus within the lumen, surrounding soft tissue inflammation, and persistent bacteremia. Patients at increased risk include those with burns, glucocorticoid use, and injection drug use. (See 'Introduction' above and 'Epidemiology' above.)

●Microbiology – The microbiology of catheter-related septic thrombophlebitis reflects the microbiology of CRBSI. The most common cause is Staphylococcus aureus; streptococci and Enterobacteriaceae are also well-described pathogens. Burn patients may have polymicrobial infection. (See 'Microbiology' above.)

●Clinical manifestations – Catheter-related septic thrombophlebitis should be suspected in patients with CRBSI and persistent bacteremia after 72 hours of appropriate antibiotic therapy. Additional clinical manifestations may include fever, erythema, tenderness, a palpable cord, and purulent drainage at the site of the involved vessel. Complications of septic thrombophlebitis include intravascular abscess, septic pulmonary emboli, and secondary pneumonia; these may also be presenting manifestations. (See 'Clinical manifestations and diagnosis' above.)

●Diagnosis – The diagnosis of catheter-related septic thrombophlebitis may be established based on radiographic evidence of thrombosis together with microbiology data. The presence of venous thrombosis may be established via duplex ultrasonography, contrast venography, or computed tomography scan with contrast; the microbiologic diagnosis can be made based on culture of blood or purulent material expressed or surgically drained from the site. (See 'Clinical manifestations and diagnosis' above.)

●Management – Principles of management for catheter-related septic thrombophlebitis include removing the focus of infection (eg, catheter removal), prompt administration of intravenous antibiotics, and consideration regarding the need for anticoagulation or surgical intervention (see 'Management' above):

•Role of catheter removal – We suggest catheter removal given high likelihood of progressive infection with antibiotic therapy alone (Grade 2C). (See 'Catheter removal' above and "Intravascular non-hemodialysis catheter-related infection: Treatment", section on 'Selecting a catheter management strategy'.)

•Antibiotic selection – The approach to selection of antibiotic therapy for catheter-related septic thrombophlebitis is the same as for treatment of CRBSI (table 1). Antibiotics should be tailored to culture and susceptibility data when available. After 48 to 72 hours of antibiotic therapy, we repeat duplex ultrasonography to evaluate for thrombus extension. (See 'Antibiotic therapy' above and "Intravascular non-hemodialysis catheter-related infection: Treatment".)

•Duration of therapy – We suggest continuation of parenteral antimicrobial therapy for four weeks (Grade 2C). The optimal duration of antibiotic therapy is uncertain; while shorter durations are given for uncomplicated CRBSI infection, we favor a longer course for infections involving the vessel wall. (See 'Antibiotic therapy' above.)

•Role of anticoagulation – In general, we suggest not treating most patients with anticoagulation (Grade 2C). In most cases, the major factors associated with induction of vascular inflammation and clotting are addressed by catheter removal and antibiotic administration. We pursue anticoagulation in the setting of persistent manifestations of infection (such as fever, hemodynamic instability, bacteremia) after 48 to 72 hours of appropriate antimicrobial therapy or duplex ultrasonography evidence of thrombus extension despite appropriate antibiotic therapy. (See 'Role of anticoagulation' above.)

•Role of surgery – In general, surgical intervention should be reserved for patients with persistent manifestations of infection despite appropriate antimicrobial therapy and anticoagulation. Potential surgical interventions include incision and drainage or excision of the affected vein and its tributaries. (See 'Role of surgery' above.)