Endotoxin levels in cirrhotic rats with sterile and infected ascites.

Endotoxin levels were measured in sterile and bacterially infected ascites in a rat model of phenobarbital and carbon tetrachloride induced cirrhosis was used. An improved chromogenic substrate assay was used to measure endotoxin. All rat ascites specimens were positive for endotoxin. In culture-negative ascites (n = 8), it ranged from 0.05 EU/ml to 0.14 EU/ml (0.08 +/- 0.04 EU/ml, mean +/- SD) (Escherichia coli 0111:B4 endotoxin was used as a reference). In culture-positive ascites (premortem n = 3, postmortem n = 1), it ranged from 0.78 EU/ml to 1.8 EU/ml (1.29 +/- 0.59 EU/ml, mean +/- SD). All rats with premortem culture-positive ascites died within two days. This model is useful to study ascites endotoxin levels. In this study, increasing levels of ascites endotoxin correlated with spontaneous bacterial peritonitis and death.