What are the KDOQI (Kidney Disease Outcomes Quality Initiative) guidelines for managing Enterobacter cloacae infection in a tunneled dialysis catheter?

Management of Enterobacter cloacae Infection in a Tunneled Dialysis Catheter

For Enterobacter cloacae infection in a tunneled dialysis catheter, the recommended approach is to use systemic antibiotics with antibiotic lock therapy for 14 days in clinically stable patients without tunnel infection, with catheter removal if clinical deterioration occurs or bacteremia persists or relapses. 1, 2

Initial Assessment and Management

• Begin parenteral antibiotic therapy immediately with coverage for gram-negative bacilli, particularly targeting Enterobacter cloacae based on local susceptibility patterns 2
• Obtain paired blood cultures from the catheter and a peripheral vein before starting antibiotics to confirm catheter-related bloodstream infection (CRBSI) 1
• Perform clinical evaluation to rule out tunnel infection, exit site infection, or other complications such as septic thrombosis, endocarditis, or metastatic infection 1
• Adjust antibiotic therapy based on culture and susceptibility results once available 2

Catheter Management Decision Algorithm

For Uncomplicated Infection (No Tunnel Infection, Patient Clinically Stable):

• Attempt catheter salvage with systemic antibiotics plus antibiotic lock therapy for 14 days 1, 2
• Antibiotic lock therapy should contain high concentrations of appropriate antibiotics based on susceptibility testing 1
• Monitor closely with clinical evaluation and additional blood cultures; remove catheter if clinical deterioration occurs 1
• Success rates for catheter salvage with antibiotic lock therapy for gram-negative infections are approximately 60-62% 3

For Complicated Infection:

• Remove the catheter immediately if any of the following are present 1, 2:
  • Tunnel infection or port abscess
  • Septic thrombosis, endocarditis, or osteomyelitis
  • Clinical deterioration despite appropriate antibiotic therapy
  • Persistent or relapsing bacteremia despite appropriate treatment
• Treat with systemic antibiotics for 4-6 weeks for complicated infections with metastatic spread 1

Antibiotic Lock Therapy Protocol

• Prepare antibiotic lock solution with concentrations 100-1000 times higher than the minimum inhibitory concentration (MIC) for the isolated organism 1
• Instill the antibiotic lock solution into the catheter lumen after each dialysis session and allow it to dwell until the next session 1, 3
• Continue antibiotic lock therapy for the full 14-day course in conjunction with systemic antibiotics 1, 2
• Be aware that antibiotic lock therapy has shown modest success rates (51-59%) in eradicating CRBSI 3, 4

Follow-up and Monitoring

• Obtain surveillance blood cultures after completion of antibiotic therapy to confirm clearance of infection 2, 3
• If catheter removal is necessary, wait until blood cultures have been negative for at least 48 hours before placing a new tunneled catheter 2
• For patients with hypoalbuminemia (serum albumin <3.5 g/dL), be aware of increased risk for recurrent bacteremia with replacement catheters 5

Special Considerations for Enterobacter cloacae

• Enterobacter species can develop resistance during therapy, particularly to third-generation cephalosporins due to inducible AmpC beta-lactamases 2
• Consider carbapenems or fourth-generation cephalosporins for definitive therapy based on susceptibility results 2
• Catheter salvage rates for gram-negative rod infections are comparable to those for gram-positive infections when using antibiotic lock therapy 3, 6

Pitfalls and Caveats

• Failure to recognize tunnel infection or other complications may lead to inappropriate attempts at catheter salvage 1
• Inadequate dwell time or concentration of antibiotic lock solution reduces effectiveness 1
• Secondary infections, particularly with Candida species, may occur during antibiotic lock therapy and require catheter removal 4
• Recurrent bacteremia within 90 days should prompt catheter removal and extended antibiotic therapy 7
• Guidewire exchange may be an alternative to complete catheter removal and delayed replacement in selected cases, with similar infection-free survival times 5, 6