Secondary bacterial peritonitis in cirrhotic patients with ascites

Bacterial peritonitis in patients with cirrhosis has a wide variety of clinical presentations. We report a group of 21 cirrhotic patients with secondary peritonitis from intra-abdominal sources. Seven had infected ascites. All of them had unrecognized secondary peritonitis which was diagnosed and treated as spontaneous (primary) bacterial peritonitis (SBP). Ascitic fluid analysis yielded a mean white blood cell count of 23,750 +/- 10,935/cu mm with 91.5% polymorphonuclear leukocytes, significantly higher than patients surveyed with SBP, 1,757 +/- 2,154/cu mm (P less than .001). Ascitic fluid protein levels were also higher than those typically seen in SBP: 4.4 +/- 1.5 gm/dl vs 0.8 +/- 0.4 gm/dl (P less than .001). The ascites: serum protein ratio was consistent with an exudate in those patients with secondary peritonitis (0.7 +/- 0.2) in contrast to typically infected transudate in patients with SBP (0.15 +/- 0.05) (P less than .001). Bacteriologic determination was similar: single organisms with Escherichia coli the most common. Often the clinical features and ascitic fluid analysis will not differentiate spontaneous from secondary peritonitis. It is, therefore, clinically prudent to consider secondary bacterial peritonitis in cirrhotic patients, especially with ascitic fluid WBC counts in excess of 5,000/cu mm and protein levels of greater than or equal to 2.5 gm/dl. Noninvasive diagnostic procedures should be included to search for sources of intra-abdominal infection.