From the Guidelines
Risk factors for spontaneous bacterial peritonitis (SBP) include advanced cirrhosis, low ascitic fluid protein levels (below 1.5 g/dL), prior episodes of SBP, gastrointestinal bleeding, and high Child-Pugh or MELD scores, as identified in the most recent guidelines on the management of ascites in cirrhosis 1. These guidelines emphasize the importance of diagnostic paracentesis to rule out SBP in all cirrhotic patients with ascites on hospital admission, particularly in those with GI bleeding, shock, fever, or other signs of systemic inflammation 1. The American Association for the Study of Liver Diseases also highlights the risk of SBP in patients with cirrhosis and acute upper gastrointestinal hemorrhage, recommending short-term selective intestinal decontamination with antibiotics like norfloxacin or IV ceftriaxone to reduce the rate of infections and improve survival 1. Key risk factors for SBP development include:
- Advanced cirrhosis
- Low ascitic fluid protein levels (<1.5 g/dL)
- Prior episodes of SBP
- Gastrointestinal bleeding
- High Child-Pugh or MELD scores
- Malnutrition
- Immunocompromised state
- Invasive procedures like paracentesis
- Proton pump inhibitor use, which may increase risk by reducing gastric acid barrier function
- Genetic factors affecting immune function Patients with these risk factors should be closely monitored, and prophylactic antibiotics, such as norfloxacin 400 mg daily or trimethoprim-sulfamethoxazole, may be recommended for high-risk individuals, especially those with low protein ascites or previous SBP episodes, as supported by studies on primary prophylaxis 1. Early recognition of these risk factors allows for preventive measures and prompt treatment if SBP develops, significantly reducing mortality rates.
From the Research
Risk Factors for Spontaneous Bacterial Peritonitis (SBP)
The risk factors for SBP in patients with cirrhosis and ascites include:
- Child-Pugh stage C 2
- Ascitic fluid polymorph-nuclear cell (PMN) count 2
- Low serum sodium levels 2, 3
- Elevated MELD score 2
- Elevated CRP levels 2
- Gastrointestinal bleeding 3
- Previous episode of SBP 3
- Refractory ascites 4
Patient Characteristics
Patients at high risk for developing SBP often have:
- Advanced liver disease, as indicated by Child-Pugh stage C 2
- Elevated ascitic fluid PMN counts (≥100 cells/μl) 2
- Hyponatremia (<125 mM) 2
- High MELD scores (≥22) 2
- Elevated CRP levels (≥3.5 mg/dl) 2
Clinical Implications
Early recognition and treatment of SBP are crucial to prevent serious morbidity and mortality 2, 4, 5. Antibiotic prophylaxis may be considered for high-risk patients, such as those with a history of SBP or gastrointestinal bleeding 3. Additionally, patients with refractory ascites should be considered for liver transplantation 4.