Spontaneous Bacterial Peritonitis. This post will cover the points you need to know for your board exams as well as for teaching residents on the daily rounds. Please don't use the information here to treat your patients.
Spontaneous Bacterial Peritonitis SBP is a common encounter with patients with liver cirrhosis as the ascitic fluid lacks the protein needed to guard against pathogens. The risk increases with variceal bleeding, use of proton pump inhibitors and low protein levels.
Don't be tricked by a patient with no symptoms or signs of peritonitis. Empirically start antibiotics in ascites patients coming with worsening renal function, encephalopathy or worsening jaundice.
The majority of cases of SBP are caused by Enterobacteriaceae (Escherichia coli and Klebsiella pneumoniae) and gram-positive cocci (Streptococcus pneumoniae, Staphylococcus species, and Enterococcus species) and hence 3rd generation cephalosporins are the mainstay of treatment.
The most common antibiotic used in treatment of Spontaneous Bacterial Peritonitis practically is intravenous ceftriaxone once daily as opposed to the recommended cefotaxime every 8 hours. In case of allergy to beta-lactams then ciprofloxacin or levofloxacin can be used.
Administration of intravenous albumin improved mortality and decreased renal failure in SBP patients.
Gram stain of paracentesis fluid is usually negative, but it will have PMN>250 in SBP and the cultures will come back positive in few days. The clinical picture will improve slowly so don't rush to change them. If symptom persists or worsen then consider broadening the antibiotic coverage.
Suspect bowel perforation if ascitic PMN>1000 or the ascitic culture is polymicrobial.
Prophylactic antibiotics are used in high-risk patients. Risk factors for SBP includes history of SBP, history of GI bleeding and total ascites protein less than 1g/dL
Patients might find this book helpful: Your Complete Guide to Liver Health.
The information in this post is not for patients and shouldn't be used in treating patients. Please refer to your doctor for medical advice.