Spontaneous bacterial peritonitis
Clinical Manifestations
- Develops in large, clinically obvious ascites 2/2 cirrhosis
- Fever - 70%
- Abdominal pain (diffuse) - 60%
- Altered mental status - 55%
- ~15% of patients have no signs/symptoms!
Diagnosis
- Paracentesis results supporting a diagnosis of SBP:
- Absolute neutrophil count > 250PMNs/microL
- SAAG > 1.1
- Total protein < 1 and Glucose > 50 (otherwise concern for 2o bacterial peritonitis)
- There is no platelet count or INR that is a contraindication to paracentesis
Distinction of spontaneous from secondary bacterial peritonitis
- Importance
- Mortality of 2o bacterial peritonitis approaches 100 percent if tx is only antibiotics without sx
- Mortality of unncessary ex lap in patient w/ SBP and wrongly suspected 2o bacterial peritonitis ~80%
- Laboratory findings
- Neutrocytic fluid (PMN ≥250) with two or more of following = strong evidence of 2o bacterial peritonitis:
- 1. Total protein concentration >1 g/dL (10 g/L)
- 2. Glucose concentration <50 mg/dL (2.8 mmol/L)
- 3. LDH greater than upper limit of normal for serum
- Should strongly suspect if ascitic alk phos >240
- Gram Stain
- Large numbers of different bacterial forms
- Imaging
- If evidence of 2o bacterial peritonitis obtain abdominal imaging
- If no evidence of free air or contrast extravasation then surgery is not indicated
Treatment
- Antibiotics
- SBP
- Broad-spectrum covering gram + and gram -
- 3rd-generation cephalosporin is agent of choice:
- Cefotaxime 2g IV q8hr or Ceftriaxone 1-2g IV q12-24hr
- If beta-lactam allergy consider ciprofloxacin 400mg IV q12hr
- 2o bacterial peritonitis
- 3rd-generation cephalosporin + metronidazole
- Albumin
- Decreases incidence of renal failure
- 1.5g/kg at time of diagnosis and 1g/kg on day 3
Source
Rosen's, UpToDate, Thomsen TW. Paracentesis. N Engl J Med 2006; 355