Spontaneous bacterial peritonitis
See Peritoneal dialysis-associated peritonitis for PD peritonitis
Background
- Abreviation: SBP
- Develops in large, clinically obvious ascites 2/2 cirrhosis
- Normal flora translocate across the bowel wall into the peritoneum
- 30% of ascitic pts will develop SBP in a given year
- There is no platelet count or INR that is a contraindication to paracentesis
Clinical Features
- Fever (70%)
- Abdominal pain (diffuse) (60%)
- Altered mental status (55%)
- ~15% of patients have no signs/symptoms
Differential Diagnosis
Diffuse Abdominal pain
- Abdominal aortic aneurysm
- Acute gastroenteritis
- Aortoenteric fisulta
- Appendicitis (early)
- Bowel obstruction
- Bowel perforation
- Diabetic ketoacidosis
- Gastroparesis
- Hernia
- Hypercalcemia
- Inflammatory bowel disease
- Mesenteric ischemia
- Pancreatitis
- Peritonitis
- Sickle cell crisis
- Spontaneous bacterial peritonitis
- Volvulus
Diagnosis
Work-Up
- Ascitic Fluid
- Cell count, glucose, protein, gm stain, culture (10cc in blood culture bottle), LDH, alk phos
- Consider alternative diagnoses at the same time
Fluid Analysis
- Paracentesis results supporting a diagnosis of SBP:
- Total WBC >500
- Absolute neutrophil count > 250
- Bacteria on gram stain (single type)
- SAAG > 1.1
- Protein < 1, Glucose > 50 (otherwise concern for secondary bacterial peritonitis)
Spontaneous versus secondary bacterial peritonitis
- Importance of distinction
- Mortality of secondary bacterial peritonitis ~100% if tx is only abx without sx
- Mortality of unnecessary sx in pt w/ SBP ~80%
- Laboratory findings
- Secondary bacterial peritonitis strongly suggested by:
- Neutrocytic fluid (PMN ≥250) w/ two or more of the following:
- Total protein concentration >1 g/dL (10 g/L)
- Glucose concentration <50 mg/dL (2.8 mmol/L)
- LDH greater than upper limit of normal for serum
- Ascitic alk phos >240
- Gram Stain
- Large numbers of different bacterial forms
- Neutrocytic fluid (PMN ≥250) w/ two or more of the following:
- Secondary bacterial peritonitis strongly suggested by:
- Imaging
- If evidence of secondary bacterial peritonitis obtain abdominal imaging
- If no evidence of free air or contrast extravasation then surgery is not indicated
- If evidence of secondary bacterial peritonitis obtain abdominal imaging
Treatment
- Antibiotics
- SBP
- Broad-spectrum covering enterobacter (63%), pneumococcus (15%), entercocci (10%)
- Anaerobes causative agent <1%
- 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
- 3rd-generation cephalosporin is agent of choice:
- Secondary bacterial peritonitis
- 3rd-generation cephalosporin + metronidazole
- Surgery
- SBP
- Albumin
- Reduces renal failure and hospital mortality
- 1.5gm/kg at diagnosis; 1gm/kg on day 3
Disposition
- Can consider discharge w/ PO abx if pt has mild, uncomplicated disease and close f/u
See Also
References
- Paracentesis. N Engl J Med 2006; 355