What is the recommended treatment for a 67-year-old patient with chronic kidney disease on thrice‑weekly hemodialysis who has a pan‑susceptible Acinetobacter baumannii infection of an internal jugular catheter, hypotension, and leukocytosis with neutrophilia?

Treatment of Pan-Susceptible Acinetobacter baumannii Catheter-Related Bloodstream Infection in Hemodialysis Patient with Sepsis

This patient requires immediate catheter removal with placement at a new site, empirical vancomycin plus gram-negative coverage (carbapenem or third-generation cephalosporin), followed by de-escalation to targeted monotherapy once susceptibilities confirm pan-susceptibility, with treatment duration of 10-14 days if symptoms resolve within 2-3 days or 4-6 weeks if bacteremia persists beyond 72 hours. 1

Immediate Catheter Management

Remove the infected catheter immediately and insert a temporary (non-tunneled) catheter at a different anatomical site. 1

• For hemodialysis catheter-related bloodstream infection (CRBSI) due to gram-negative bacilli other than Pseudomonas (which includes Acinetobacter baumannii), the IDSA guidelines allow for initial empirical antibiotics without immediate catheter removal only if the patient is hemodynamically stable 1
• However, this patient presents with hypotension, leukocytosis (WBC 22,000), and neutrophilia—clear signs of severe sepsis 1
• The presence of hemodynamic instability mandates immediate catheter removal rather than attempting catheter salvage 1
• If absolutely no alternative sites exist for catheter insertion, guidewire exchange is acceptable, but given the severity of presentation, removal and placement at a new site is strongly preferred 1

Empirical Antibiotic Therapy

Initiate vancomycin 15-20 mg/kg (actual body weight) after dialysis PLUS a carbapenem (meropenem or imipenem) or third-generation cephalosporin (ceftazidime) dosed for hemodialysis patients. 1

• The IDSA recommends empirical coverage including vancomycin and gram-negative coverage based on local antibiogram for all hemodialysis CRBSI 1
• Options for gram-negative coverage include third-generation cephalosporin, carbapenem, or β-lactam/β-lactamase combination 1
• For pan-susceptible Acinetobacter baumannii, carbapenems (imipenem, meropenem, doripenem) are the mainstay of treatment 2
• Sulbactam-containing regimens (ampicillin-sulbactam) are also highly effective for susceptible strains 1, 2

De-escalation Strategy

Once susceptibilities confirm pan-susceptibility, discontinue vancomycin and continue carbapenem monotherapy or switch to ampicillin-sulbactam if susceptible to sulbactam. 1

• Gram-negative coverage with piperacillin-tazobactam should be discontinued once the pathogen is identified as not requiring dual coverage 1
• For pan-susceptible Acinetobacter, monotherapy with an active agent is appropriate once the patient is clinically stable 1
• Ampicillin-sulbactam is conditionally recommended for Acinetobacter baumannii susceptible to sulbactam, particularly for hospital-acquired/ventilator-associated pneumonia, and can be extrapolated to bloodstream infections 1

Treatment Duration Algorithm

Assess clinical response at 48-72 hours to determine treatment duration: 1

• If symptoms (fever, chills, hemodynamic instability) resolve within 2-3 days AND blood cultures clear AND no metastatic infection is present: Treat for 10-14 days total 1
• If bacteremia persists >72 hours after catheter removal: Extend treatment to 4-6 weeks 1
• If endocarditis or suppurative thrombophlebitis develops: Treat for 4-6 weeks 1
• If osteomyelitis develops: Treat for 6-8 weeks 1

Critical Assessment for Metastatic Complications

Evaluate for endocarditis, suppurative thrombophlebitis, and metastatic seeding before finalizing treatment duration. 1

• Obtain repeat blood cultures 48-72 hours after catheter removal to document clearance 1
• Consider echocardiography if fever persists beyond 72 hours despite appropriate antibiotics and catheter removal 1
• Physical examination should assess for exit site or tunnel infection, though this is less relevant after catheter removal 1

Timing of New Long-Term Catheter Placement

Place a new long-term hemodialysis catheter only after obtaining negative blood cultures. 1

• Do not place a permanent catheter until bacteremia has cleared 1
• Use temporary access until blood cultures are negative 1

Common Pitfalls to Avoid

Do not attempt catheter salvage with antibiotic lock therapy in this hemodynamically unstable patient. 1

• Antibiotic lock therapy is only appropriate for patients who achieve clinical stability within 2-3 days and have no metastatic infection 1
• The presence of hypotension at presentation indicates severe sepsis and mandates catheter removal 1

Do not use polymyxins or tigecycline for pan-susceptible Acinetobacter baumannii. 1, 2

• These agents should be reserved for carbapenem-resistant strains 1, 2
• Carbapenems remain the preferred agents for susceptible strains 2

Do not use cefiderocol for Acinetobacter baumannii bloodstream infections. 1

• The ESCMID guidelines conditionally recommend against cefiderocol for carbapenem-resistant Acinetobacter baumannii (CRAB) due to concerns about mortality in clinical trials 1
• This recommendation applies even more strongly to pan-susceptible strains where better alternatives exist 1

Surveillance After Treatment Completion

This recommendation does not apply since the catheter was removed rather than retained. 1

• Surveillance blood cultures 1 week after antibiotic completion are only necessary if the catheter was retained with antibiotic lock therapy 1
• Since this patient requires catheter removal due to hemodynamic instability, post-treatment surveillance cultures are not mandated by guidelines 1