Role of intestinal bacterial overgrowth and intestinal motility in bacterial translocation in experimental cirrhosis.
BACKGROUND
Intestinal bacterial overgrowth (IBO) is related to small bowel motility and has been involved in the pathogenesis of bacterial translocation (BT) in experimental models, and both overgrowing gut flora and translocating bacteria to mesenteric lymph nodes are common features in cirrhosis.


OBJECTIVE
The aims of this study were to analyze cecal aerobic bacteria and intestinal transit in cirrhotic rats, and their relationship with BT, evaluating the role of intestinal bacterial overgrowth and small bowel dismotility in the development of BT in experimental cirrhosis.


METHODS
We included twenty-seven male Sprague-Dawley rats with carbon tetrachloride-induced cirrhosis without ascites and ten controls. Cultures of mesenteric lymph nodes (MLN), peripheral and portal blood, liver, spleen and cecal samples were carried out. Small intestinal transit was determined in ten cirrhotic rats and in ten control rats.


RESULTS
The prevalence of bacterial translocation was 56%. Total cecal aerobic bacteria count was significantly higher in cirrhotic rats than in control rats (p < 0.001). Cirrhotic rats with translocated bacteria had higher total aerobic intestinal counts than culture-negative MLN bacteria (p < 0.05). The prevalence of total intestinal bacterial overgrowth in cirrhotic animals was 67%, and 0% in control animals (p < 0.001). According to BT, total IBO was more frequent in cirrhotic rats with BT versus those without BT (93 vs. 33%) (p < 0.001). Of the translocating bacteria, 95.6% were found to be overgrown in the cecum. The small-intestinal transit was slower in cirrhotic rats (60.5 +/- 12.7 cm vs. 81.2 +/- 5.7 cm) than in control animals (p < 0.001).


CONCLUSIONS
These results suggest that the increase of intestinal aerobic bacteria in experimental cirrhosis is associated with translocation. In addition, IBO is frequent in cirrhotic rats, and is supposed to play an important role in the development of BT. Impaired motility of the small intestine is a common feature in cirrhosis and may be implicated in the pathogenesis of IBO.
Sánchez
E
E
Service of Gastroenteroloyg, Hospital Universitario Marqués de Valdecilla, Santander, Spain.
Casafont
F
F
Guerra
A
A
de Benito
I
I
Pons-Romero
F
F
D000704:Analysis of Variance; D000818:Animals; D001420:Bacteria, Aerobic / Q000254:growth & development* / Q000302:isolation & purification; D018988:Bacterial Translocation; D016022:Case-Control Studies; D005769:Gastrointestinal Motility / Q000502:physiology; D007422:Intestines / Q000382:microbiology*; D008106:Liver Cirrhosis, Experimental / Q000382:microbiology*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley