MICROBIAL TRANSLOCATION AND IMPAIRMENT OF MUCOSAL IMMUNITY INDUCED BYAN ELEMENTAL DIET IN RATS IS PREVENTED BY SELECTIVE DECONTAMINATION OF THE DIGESTIVE-TRACT
G. Spath et A. Hirner, MICROBIAL TRANSLOCATION AND IMPAIRMENT OF MUCOSAL IMMUNITY INDUCED BYAN ELEMENTAL DIET IN RATS IS PREVENTED BY SELECTIVE DECONTAMINATION OF THE DIGESTIVE-TRACT, The European journal of surgery, 164(3), 1998, pp. 223-228
Objective: To assess the effect of selective decontamination of the di
gestive tract (SDD) on intestinal secretory immunoglobulin A (sIgA) co
ncentrations in a model of intestinal bacterial overgrowth and bacteri
al translocation induced by an elemental diet in rats. Design: Laborat
ory study. Setting: University hospital, Germany. Material: 45 specifi
c pathogen free female Crl:CDR BR rats. Interventions: For 7 days, 3 g
roups of rats were fed orally with standard chow (n = 15), total paren
teral nutrition solution (ORAL-TPN, n = 15), or ORAL-TPN plus tobramyc
in (20 mg/L) and polymyxin E (25 mg/L) (ORAL-TPN + SDD). Main outcome
measures: Bacterial translocation to mesenteric lymph nodes (MLN), num
bers of Gram negative enterobacteria and total aerobic bacteria in the
caecum, and intestinal concentrations of sIgA. Results: The incidence
of bacterial translocation was significantly increased in the group g
iven ORAL-TPN (8/15, 53%) compared with the group given chow (1/15, 7%
, p < 0.01). Supplementation of ORAL-TPN with SDD reduced translocatio
n to 0/15. The ORAL-TPN group had a pronounced overgrowth of aerobic b
acteria in the caecum, mainly by Gram negative enterobacteria, which w
as prevented by the SDD. The concentrations of intestinal sIgA were si
gnificantly reduced in the ORAL-TPN group. SDD resulted in both the so
luble and insoluble sIgA fractions in the gut being within the referen
ce ranges. Conclusion: SDD prevents Gram negative caecal overgrowth an
d translocation to MLN in rodents fed on ORAL-TPN. The significantly r
educed mucosal immunity caused by ORAL TPN alone is restored by SDD, a
lthough one might have expected a further reduction in sIgA concentrat
ions with lower microbial populations than in the ORAL-TPN group. Not
only does SDD not seem to affect the mucosa associated immune system a
dversely, but also depressed mucosal immunity was restored.