What is the treatment for vein thrombosis due to infectious causes?

Treatment of Venous Thrombosis Due to Infectious Causes

For venous thrombosis associated with infection, parenteral anticoagulation with therapeutic weight-adjusted low molecular weight heparin (LMWH) or intravenous unfractionated heparin (UFH) is the recommended initial treatment, with LMWH preferred to limit staff exposure and avoid potential heparin resistance. 1

Initial Management

• For patients with venous thrombosis due to infectious causes, prompt initiation of anticoagulation therapy is essential to prevent further thromboembolic events 1
• In patients with septic thrombosis, the involved catheter should be removed, especially when there is suppuration, persistent bacteremia/fungemia, or metastatic infection 1
• Incision and drainage with excision of the infected peripheral vein and any involved tributaries should be performed when infection extends beyond the vein into surrounding tissue 1
• Surgical exploration is needed when infection extends beyond the vein into surrounding tissue 1

Anticoagulation Therapy

• For acutely ill hospitalized patients with proximal DVT or pulmonary embolism due to infection, initial parenteral anticoagulation with therapeutic weight-adjusted LMWH or IV UFH is recommended 1
• LMWH is preferred over UFH in most cases due to:
  • Limited staff exposure 1
  • Reduced risk of heparin resistance 1
  • Superior safety profile and more predictable antithrombotic effects 1
• In patients with severe renal failure (creatinine clearance <25-30 ml/min), UFH with careful monitoring is recommended 1

Special Considerations for Septic Thrombosis

• Heparin should be used in the treatment of septic thrombosis of the great central veins and arteries 1
• Duration of antimicrobial therapy for septic thrombosis of great central veins should be the same as that for endocarditis (4-6 weeks) 1
• For septic thrombosis due to Candida species, a prolonged course of amphotericin B therapy is recommended; fluconazole can be used if the strain is susceptible 1
• Thrombolytic agents in addition to antimicrobial agents are not recommended for patients with catheter-related bloodstream infection and thrombus formation 1

Catheter Management in Catheter-Related Thrombosis

• For infected thrombus, the catheter should be removed 1
• In cases where the catheter is not infected, malpositioned, or obstructed, it may be maintained as it could be useful for local thrombolytic treatment when indicated 1
• Careful removal is advised as there is a risk of embolization of clot partially attached to the catheter which may become dislodged during removal 1

Duration of Therapy

• For patients with COVID-19 and proximal DVT or PE (which may have an infectious component), anticoagulation therapy is recommended for a minimum duration of three months 1
• For other infectious causes of venous thrombosis, the duration of anticoagulation should be at least 3 months 1
• In cases of persistent risk factors or unprovoked VTE, extended treatment beyond 3 months should be considered 2

Thrombolytic Therapy

• Thrombolytic treatment should be considered only for specific subgroups of patients such as:
  • Those with pulmonary embolism presenting with severe right ventricular dysfunction 1
  • Patients with massive ilio-femoral thrombosis at risk for limb gangrene where rapid venous decompression and flow restoration may be desirable 1
  • In patients with COVID-19 and both acute, objectively confirmed PE and hypotension or signs of obstructive shock due to PE, and who are not at high risk of bleeding 1

Monitoring and Follow-up

• Regular monitoring of anticoagulation therapy is essential, especially when using vitamin K antagonists 1
• For patients with persistent risk factors for thrombosis, closer monitoring and potentially longer duration of anticoagulation may be necessary 2

Potential Pitfalls and Complications

• Delaying anticoagulation in patients with confirmed thrombosis increases the risk of embolic events 3
• Premature discontinuation of anticoagulation before resolution of the thrombus may lead to recurrence 3
• Excessive pressure should be avoided when instilling thrombolytic agents into catheters as this could cause rupture or expulsion of the clot into circulation 4
• Bleeding is the most frequent adverse reaction associated with thrombolytics and should be carefully monitored 4