Spontaneous Bacterial Peritonitis (SBP) Diagnosis & Treatment — free guideline decision tool

This tool diagnoses and treats spontaneous bacterial peritonitis using ascitic-fluid PMN, acquisition setting, and prior history, with empiric antibiotics, albumin, and prophylaxis.

PMN ≥ 250/mm³ → SBP. Community → cefotaxime/ceftriaxone; nosocomial/high-resistance → broad-spectrum per local resistance. Albumin 1.5 g/kg day 1 + 1 g/kg day 3. Prior history → long-term quinolone prophylaxis.

Use to confirm SBP at PMN ≥ 250/mm³, choose empiric antibiotics by setting, add albumin to reduce hepatorenal syndrome, and decide secondary prophylaxis.

Albumin alongside antibiotics is most beneficial when creatinine > 1 mg/dL, BUN > 30, or bilirubin > 4, where it reduces hepatorenal syndrome and death. (original synthesis · not guideline verbatim) A 48 h ascitic-PMN recheck assesses response; an insufficient drop prompts adjustment or exclusion of secondary peritonitis. Non-selective β-blockers are stopped in hypotensive or refractory SBP.

For licensed clinicians and clinical researchers. Interpret results with history, investigations and local protocols; not a diagnosis or prescription, and not a substitute for multidisciplinary decision-making or local guidelines.

Inputs: Ascitic-fluid neutrophils (PMN) ≥ 250/mm³ (confirms SBP), Acquisition setting Community-acquired, Prior SBP history Present → Result: Disposition Empiric antibiotics + albumin（Diagnosis: Ascitic PMN ≥ 250/mm³ (with or without positive culture) diagnoses SBP; all hospitalized cirrhotic ascites or suspected infection should have diagnostic paracentesis, bedside inoculation of ≥ 10 mL ascites into blood-culture bottles plus blood cultures, without waiting for results, Antibiotics: Community-acquired: third-generation cephalosporin (cefotaxime 2 g q8h, or ceftriaxone) first-line; course usually ≥ 5 days and until ascitic PMN < 250, recheck ascitic PMN at 48 h to assess response (insufficient drop needs adjustment or exclusion of secondary peritonitis), Albumin: 1.5 g/kg on diagnosis day + 1 g/kg on day 3 (especially creatinine > 1 mg/dL, BUN > 30, or bilirubin > 4), reducing hepatorenal syndrome and mortality） Inputs: Ascitic-fluid neutrophils (PMN) < 250/mm³, Acquisition setting Nosocomial / recent antibiotics / high resistance risk, Prior SBP history Absent → Result: Diagnosis PMN < 250: does not support SBP（Interpretation: Ascitic neutrophils (PMN) < 250/mm³: does not meet SBP criteria; correlate clinically to seek another infection source, repeat paracentesis if needed, Caveat: With strong clinical suspicion (fever, abdominal pain/tenderness, encephalopathy, or renal injury), empiric treatment may still be given with ascitic + blood cultures sent; a positive culture with PMN < 250 is monomicrobial non-neutrocytic bacterascites, individualized, Basis: AASLD/EASL guidelines on cirrhotic ascites and SBP）