幽门螺杆菌感染儿童厌食机制研究

The mechanism of anorexia in children with Helicobacter pylori infection

目的探讨Ghrelin表达以及不同幽门螺杆菌(H.pylori)毒力基因型在H.pylori感染患儿厌食发病机制中的作用。方法 H.pylori感染患儿60例,根据临床表现分为厌食(n=30例)和非厌食(n=30例)组。应用RT-PCR方法检测胃黏膜Ghrelin mRNA表达水平,比较两组患儿以及厌食患儿在H.pylori根治前后的差异。同时采用PCR方法检测所有患儿的H.pylori毒力cagA/vacA基因并分型。结果 H.pylori感染厌食患儿胃黏膜GhrelinmRNA表达低于非厌食患儿,两组差异有统计学意义(P<0.01);厌食患儿H.pylori根治后Ghrelin mRNA表达明显升高,与根治前比较差异有统计学意义(P<0.05);同时患儿食欲改善,体质量增长显著。厌食与非厌食患儿感染的H.pylori均为Ⅰ型毒力株,厌食患儿的cagA m1阳性率高于非厌食患儿,厌食患儿的H.pylori基因型以s1/m1多见。结论 Ghrelin在H.pylori感染厌食患儿中表达降低,而H.pylori根治后表达升高,H.pylori可能通过影响Ghrelin分泌而导致厌食;毒力较强的H.pylori vacA s1/m1基因型感染易导致患儿厌食。

Objective To study the expression of Ghrelin and the virulence genes of Helicobacter pylori（H.pylori）in the mechanism of anorexia in children with H.pylori infection.Methods Sixty children with H.pylori infection were recruited and divided into two groups based on the presence of anorexia,anorexia group（n = 30）and non-anorexia group（n = 30）.The expression of Ghrelin mRNA in gastric mucosa was detected by RT-PCR and compared.The cagA/vacA genotyping of H.pylori was isolated and tested by PCR.Results The expression of Ghrelin mRNA in gastric mucosa was significantly decreased in anorexia group than in non-anorexia group（P 0.01）.In anorexia group,the expression of Ghrelin mRNA after H.pylori eradication therapy was significantly increased than before（P 0.05）.Meanwhile,the apptite was improved and the weight gain was significantly increased in anorexia group.The strains of H.pylori isolated were type I in all children.The positive rate of cagA m1 in anorexia group was higher than that in non-anorexia group.More s1/m1 genotypes was found in anorexia group.Conclusions The expression of Ghrelin mRNA was decreased in anorexia children with H.pylori infection and increased after H.pylori eradication therapy.H.pylori may cause anorexia through influencing the Ghrelin secretion.Different genotypes（vacA s1/m1）may be the key factor on the Ghrelin secretion for anorexia children with H.pylori infection.