Spontaneous Bacterial PeritonitisKatherine YuMay 2014

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

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?

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

DiagnosisType Ascites cell

count/mm3Ascites culture

Spontaneous bacterial peritonitis (SBP)

≥ 250 PMNs Usually polymicrobial.

Microbiology: 70% GNR (E. coli, Klebsiella), 30% GPC (enterococcus, S. pneumo). Less commonly nosocomial (fungi, pseudomonas)

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

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

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

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?

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.