Analysis of correlation between intestinal microflora and intestinal mucosa immune in the elderly / 中华老年医学杂志

ABSTRACT

Objective To investigate the characteristics of intestinal microflora and its effect on fecal secretory immunoglobulin A (sIgA) in the elderly. Methods All 104 cases were assigned to two groups the control group (healthy adults, age<60 years ,n=36) and the elderly group (healthy elderly persons, age ≥60 years, n=68). Feces samples of all cases were cultured under both aerobic and anaerobic conditions for the 6 bacteria (4 kinds of anaerobes and 2 kinds of aerobes) and the yeasts. The ratio of bifidobaeterium to Enterobacteria (the ratio of B/E) was calculated, which reflected personal colonization resistance. The fecal sIgA was also measured. Results Compared with control group, the number of fecal bifidobacterium and the ratio of B/E were significantly decreased in elderly group[(9.1±1.1)vs. (10.2±0.8)lgCFU/g,P<0. 01 ;(1. 02±0.14) vs. (1.24± 0. 18), P < 0. 01], and the number of enterobacteria and peptostreptococcus was significantly increased in elderly group [(9.2±1.3) vs. (8. 2±0.7) lgCFU/g, P < 0. 05 ; (8. 5 ±1.4) vs. (7.1 ± 1.6)lgCFU/g, P<0. 05]. The fecal slgA was much lower than that in control group [(652.9± 184.3) vs. (793. 5±150. 3)μg/ml, P<0. 05]. Moreover, the quantity change of bifidobacterium was correlated with the concentration of fecal sIgA(r=0. 562, P<0. 01). Conclusions The number of fecal bifidobacterium is significantly decreased, while the number of enterobacteria and peptostreptococcus is significantly increased in elderly persons. The colonization resistance is significantly decreased and the intestinal immuno-barrier function is injuried in elderly persons, which have influenced the intestinal microflora.