Spontaneous Bacterial Peritonitis Information - symptom, cause, picture, treatment of
Spontaneous Bacterial Peritonitis
Spontaneous Bacterial Peritonitis Information
"Spontaneous" bacterial infection of ascitic fluid occurs in the absence of an apparent intra-abdominal source of infection. It is seen with few exceptions in patients with ascites caused by chronic liver disease. Translocation of enteric bacteria across the gut wall or mesenteric lymphatics leads to seeding of the ascitic fluid, as may bacteremia from other sites. Approximately 20–30% of cirrhotic patients with ascites develop spontaneous peritonitis; however, the incidence is greater than 40% in patients with ascitic fluid total protein < 1 g/dL, probably due to decreased ascitic fluid opsonic activity.
Virtually all cases of spontaneous bacterial peritonitis are caused by a monomicrobial infection. The most common pathogens are enteric gram-negative bacteria (E coli, Klebsiella pneumoniae, Enterococcus species) or gram-positive bacteria (Streptococcus pneumoniae, viridans streptococci). Anaerobic bacteria are not associated with spontaneous bacterial peritonitis.
Clinical Findings of Spontaneous Bacterial Peritonitis
Symptoms and Signs of Spontaneous Bacterial Peritonitis
Eighty to 90 percent of patients with spontaneous bacterial peritonitis are symptomatic; in many cases the presentation is subtle. Spontaneous bacterial peritonitis may be present in 20% of patients hospitalized with chronic liver disease in the absence of any suggestive symptoms or signs.
The most common symptoms are fever and abdominal pain, present in two-thirds of patients. Spontaneous bacterial peritonitis may also present with a change in mental status due to exacerbation or precipitation of hepatic encephalopathy, or sudden worsening of renal function. Physical examination typically demonstrates signs of chronic liver disease with ascites. Abdominal tenderness is present in less than 50% of patients, and its presence suggests other processes.
Treatment of Spontaneous Bacterial Peritonitis
Empirical therapy for spontaneous bacterial peritonitis should be initiated with a third-generation cephalosporin such as cefotaxime (dosage: 2 g intravenously every 8–12 hours depending on renal function), which covers 98% of causative agents of this disorder. If enterococcus infection is suspected, ampicillin may be added. Because of a high risk of nephrotoxicity in patients with chronic liver disease, aminoglycosides should not be used. Although the optimal duration of therapy is unknown, a course of 5 days is sufficient in most patients, or until the ascites fluid PMN count decreases to < 250 cells/L. Renal failure develops in up to 40% of patients and is a major cause of death. In patients given intravenous albumin, 1.5 g/kg on day 1 and 1 g/kg on day 3, the incidence of renal failure and mortality are reduced both during hospitalization and at follow-up. Patients with suspected secondary bacterial peritonitis should be given broad-spectrum coverage for enteric aerobic and anaerobic flora with a third-generation cephalosporin and metronidazole pending identification and definitive (usually surgical) treatment of the cause. In fact, the most effective treatment for spontaneous bacterial peritonitis is liver transplant.
Prognosis of Spontaneous Bacterial Peritonitis
The mortality rate of spontaneous bacterial peritonitis exceeds 30%. However, if the disease is recognized and treated early, the rate is less than 10%. As the majority of patients have underlying severe liver disease, many may die of liver failure, hepatorenal syndrome, or bleeding complications from portal hypertension.