In an adult patient with cirrhosis and spontaneous bacterial peritonitis treated with ceftriaxone 2 g intravenously daily, is there any benefit to continuing ceftriaxone after clinical improvement and ascitic fluid neutrophil count have fallen below 250 cells/µL?

Continuing Ceftriaxone After SBP Clearance

There is no benefit to continuing ceftriaxone after documented clearance of spontaneous bacterial peritonitis (ascitic fluid neutrophil count <250 cells/µL), and antibiotics should be discontinued at that point. 1, 2

Evidence-Based Treatment Duration

Standard 5-day therapy is sufficient for uncomplicated SBP, and continuation beyond documented clearance provides no additional benefit. 3, 1

• A 5-day course of ceftriaxone is as effective as 10 days of treatment for SBP resolution, with infection resolution rates of 77-98% 3, 1
• Treatment can be safely discontinued once the ascitic fluid PMN count falls below 250 cells/mm³, which typically occurs by day 4-5 of appropriate therapy 1, 2
• One prospective study of 33 cirrhotic patients demonstrated that if the PMN count is <250 cells/mm³ on day 5 of ceftriaxone treatment, the antibiotic can be discontinued without adverse outcomes 2

Monitoring Requirements to Guide Discontinuation

Perform repeat paracentesis at 48 hours to assess treatment response; if PMN count has decreased to <25% of baseline, continue to day 5 and recheck. 3, 1, 4

• Treatment success is defined as a decrease in ascitic neutrophil count to <25% of pre-treatment value by 48 hours 3, 1
• If the PMN count is <250 cells/mm³ at 48 hours and the patient is clinically improving, you can consider stopping at that point rather than completing 5 days 2
• If the PMN count fails to decrease by at least 25% at 48 hours, suspect treatment failure and broaden antibiotic coverage 3, 1

Critical Transition: From Treatment to Prophylaxis

Once SBP has resolved (PMN <250 cells/µL), immediately transition to indefinite secondary prophylaxis with norfloxacin 400 mg daily or ciprofloxacin 500 mg daily—do not continue ceftriaxone. 1, 5

• Patients who survive an episode of SBP have a 70% one-year recurrence rate without prophylaxis 1
• Long-term prophylaxis with norfloxacin reduces SBP recurrence from 68% to 20% 1, 5
• This prophylaxis should continue indefinitely until liver transplantation or death 1

Common Pitfalls to Avoid

Do not confuse treatment duration with prophylaxis duration. 1

• Treatment with ceftriaxone is short-term (5 days or until clearance) 3, 1
• Prophylaxis with quinolones is indefinite and begins after treatment ends 1, 5
• Continuing ceftriaxone beyond clearance exposes patients to unnecessary risks (C. difficile infection, drug-resistant organisms, gallbladder pseudolithiasis) without benefit 6

Do not wait for culture results to guide duration—the PMN count is the key determinant. 1, 4

• Culture-negative neutrocytic ascites should be treated identically to culture-positive SBP 4
• Both have similar morbidity and mortality 4

Exceptions Requiring Extended Therapy

Extend ceftriaxone beyond 5 days only if:

• Clinical response is inadequate at 48-72 hours despite appropriate initial therapy 1
• Culture results reveal resistant organisms requiring longer treatment 1
• Secondary bacterial peritonitis is suspected (multiple organisms, ascitic protein >1 g/dL, LDH > serum upper limit, glucose <50 mg/dL) 1, 4

In these scenarios, the issue is treatment failure or wrong diagnosis—not a need for prolonged therapy after documented clearance.