EFFECT OF SELECTIVE BOWEL DECONTAMINATION WITH NORFLOXACIN ON SPONTANEOUS BACTERIAL PERITONITIS, TRANSLOCATION, AND SURVIVAL IN AN ANIMAL-MODEL OF CIRRHOSIS

Selective bowel decontamination with the orally administered quinolone antibiotic, norfloxacin, has been shown to suppress gut gram-negative bacteria and help prevent gram-negative infections in cirrhotic patie nts who are at high risk of bacterial infection. Because this drug doe s not eradicate gram-positive organisms, it is conceivable that gram-p ositives could replace the sup pressed gram-negatives in the gut and l ead to subsequent infection. Also the effect of norfloxacin on translo cation (as defined by culture positivity of mesenteric lymph nodes) ha s received little attention. In this study, the effect of oral norflox acin on translocation, bacterial peritonitis, and survival was investi gated in an animal model of carbon tetrachloride-induced cirrhosis and ascites. Treated rats received daily doses of orally administered nor floxacin from the onset of cirrhosis until they died or were killed. C ontrols received no antibiotic. Norfloxacin led to a reduction in bact erial peritonitis from 70% in untreated cirrhotic controls to 28% in t reated cirrhotic rats; these data were statistically significant (P = .012). There was no effect on overall translocation rate (28% with nor floxacin vs. 50% without norfloxacin) (P > .1). Gram-positives were is olated in 100% of the bacterial peritonitis episodes and in 71.4% of c ulture-positive mesenteric lymph nodes in treated animals compared wit h only 25% of peritonitis episodes and 10% of culture-positive mesente ric lymph nodes of untreated cirrhotic controls (P < .01 for peritonit is and P < .05 for translocation), The survival rate was not different between groups (P > .1). Although norfloxacin was associated with a 6 0% reduction in the overall rate of peritonitis, this drug increased t he risk of gram-positive translocation and gram-positive peritonitis, and did not prolong survival in this animal model.