Spontaneous Bacterial Peritonitis

1. Spontaneous Bacterial Peritonitis Katherine Yu May 2014

2. Objectives • Know how to diagnose spontaneous bacterial peritonitis (SBP) • Know how to treat SBP • Know the indications for the primary prophylaxis of SBP and the treatment regimen

3. Case • A 45 year old man is admitted to the hospital for a two day history of fever and abdominal pain. His medical history is notable for cirrhosis due to chronic hepatitis C, esophageal varices, ascites, and minimal hepatic encephalopathy. • On physical exam, T 36.5C, BP 100/50, P 84, RR 20. BMI 28. Abdominal exam discloses distension consistent with ascites. • Labs: WBC 3.5, Hgb 10, Plt 70. Cr 1.8. Total bilirubin 4. ALT 30, AST 40. Diagnostic paracentesis discloses a cell count of 2,000/microliter with 20% neutrophils, a total protein level 1 g/dL, and an albumin of 0.7 g/dL. Ascitic fluid culture is positive. • What is his diagnosis? • What is the most appropriate treatment?

4. Diagnosis • SBP is diagnosed by an ascites cell count of ≥ 250 PMNs/mm3 and a positive ascitic fluid culture • How to calculate the number of PMNs in ascitic fluid: • Ascitic fluid cell count multiplied by the percentage of PMNs • Example: • Ascitic fluid cell count is 1,000 and there are 30% PMNs • The number of PMNs is 1,000 x 0.3 = 300

5. Diagnosis • Be aware there is also culture negative neutrocytic ascites (CNNA) with ≥ 250 PMNs/mm3 but with negative ascites culture.

6. Treatment • Cefotaxime 2 gm IV q8 hours for 5 days • Oral fluoroquinolone can be used for uncomplicated SBP (stable renal and hepatic function and no encephalopathy) • The addition of IV albumin 1.5 g/kg at the time of diagnosis and 1 g/kg on day three may increase survival and reduce the rate of renal impairment when compared with antibiotics alone • If patient is not improving, consider repeat paracentesis at 48 hours

7. Indications for Prophylaxis • Primary prophylaxis: • If ascitic fluid total protein (AFTP) < 1.5 & Na <130, Cr >1.2 or Child-Pugh score B • Secondary prophylaxis: • If prior history of SBP • Regimen: • norfloxacin 400 mg po daily -OR - • Bactrim DS daily • Benefits of prophylaxis: • Improves 1 year survival probability • Reduces 1 year probability of SBP

8. Back to the case • A 45 year old man is admitted to the hospital for a two day history of fever and abdominal pain. His medical history is notable for cirrhosis due to chronic hepatitis C, esophageal varices, ascites, and minimal hepatic encephalopathy. • On physical exam, T 36.5C, BP 100/50, P 84, RR 20. BMI 28. Abdominal exam discloses distension consistent with ascites. • Labs: WBC 3.5, Hgb 10, Plt 70. Cr 1.8. Total bilirubin 4. ALT 30, AST 40. Diagnostic paracentesis discloses a cell count of 2,000/microliter with 20% neutrophils, a total protein level 1 g/dL, and an albumin of 0.7 g/dL. Ascitic fluid culture is positive. • What is his diagnosis? • What is the most appropriate treatment?

9. Summary • Spontaneous bacterial peritonitis (SBP) is diagnosed by an ascites fluid cell count of ≥ 250 PMNs and a positive ascites fluid culture. • Treatment of SBP is IV cefotaxime 2 gm IV q8 hours and IV albumin 1.5 g/kg on day one and 1 g/kg on day 3. The concomitant use of albumin with antibiotic therapy is associated with a survival benefit compared with antibiotic therapy alone. • Primary prophylaxis of SBP is indicated if ascitic fluid total protein (AFTP) < 1.5 & Na <130, Cr >1.2 or Child-Pugh score B. The treatment is daily oral norfloxacin or Bactrim DS.