迁延性慢性腹泻病患儿回肠末端纹状缘肽酶及双糖酶活性的初步研究

摘要 目的 测定迁延性慢性（迁慢性）腹泻病患儿回肠末端纹状缘肽酶及双糖酶活性水平，探讨回肠末端黏膜组织学形态与纹状缘肽酶、双糖酶活性水平的关系。方法 收集结肠镜检查患儿回肠末端黏膜标本行病理学检查，以迁慢性腹泻病及非腹泻病组患儿为观察对象，两组中病理学检查为慢性炎症者为慢性炎症组，余为黏膜正常组。非腹泻病组中病理学检查结果正常者为对照组，测定回肠末端黏膜标本中纹状缘肽酶和双糖酶活性水平。结果 2007年7月至2008年3月在广州医学院附属广州市儿童医院共收集到27例回肠黏膜标本，光镜下见其绒毛形态均正常，病理学检查10/27（37.0％）例有慢性炎症。迁慢性腹泻病组纹状缘肽酶及双糖酶活性水平与对照组差异均无统计学意义（P>0.05），慢性炎症组纹状缘肽酶及双糖酶活性水平与黏膜正常组差异均无统计学意义（P>0.05）。结论 回肠末端黏膜绒毛正常的迁慢性腹泻病患儿，其纹状缘肽酶及双糖酶活性水平无明显变化。慢性炎症且绒毛正常的回肠末端黏膜，其纹状缘肽酶活性及双糖酶无明显变化。

Preliminary study on the activities of terminal ileum mucosal brush border peptidase and disaccharidase in children with persistent diarrhea and chronic diarrhea

bstract Objective To investigate the changes of terminal ileum brush border peptidase and disaccharidase activities in persistent diarrhea and chronic diarrhea children. To investigate the relationship between ileum mucosal histology and the ileal brush border peptidase and disaccharidase activities.Methods The terminal ileal mucosal specimens were collected from children who were taken enteroscopy during July 2007 to March 2008 in our hospital.Two ileal mucosal specimens were obtained from the terminal ileum endoscopically. One was stored intact at -80℃ for assaying of brush border peptidases and disaccharidase activities，and another was placed in 10% formalin for histologic examination. All children were divided into two groups, persisting diarrhea and chronic diarrhea group and non diarrhea group. The terminal ileal mucosal histologic changes were graded according to the Marsh classification as follows: normal villus, mild villous atrophy, moderate villous atrophy and severe villus atrophy. If there was no villous atrophy, they were classified into two groups according to McHugh : normal terminal ileum mucosa and chronically inflamed terminal ileum mucosa. The ileal brush border peptidase and disaccharidase activities of persistent diarrhea and chronic diarrhea group were compared to non diarrhea group with normal mucosa. Protein concentrations in homogenates were determined according to the method of BCA. Enzyme activities in homogenates were expressed as international units per gram of protein .One unit corresponded to the hydrolysis of 1 μmol of substrate per minute under the assay conditions. All data were analyzed by SPSS version 14.The normality of brush border disaccharidases activities were determined by Kolmogorov Smirnov test, if the data were not normally distributed, a logarithmic transformation was performed to normalize the data. All the results were represented as mean±standard deviation. Differences between groups were determined by two group t test, P values <0.05 was considered to be significant.Results Terminal ileal mucosal specimens were collected from 27 children, 12 chilidren were persistent diarrhea and chronic diarrheas. Fifteen children were non diarrhea group who accepted colonoscopy owing to the gastrointestinal symptoms such as hemafecia，abdominal pain, swollen, polypus, pale, etc. Of the 27 children,20 were boys and 7 were girls(2.86∶1). Ages ranged from 1 to 12 years (mean age, 5 years).All ileal mucosal villi were normal, but there were 17 children with normal terminal ileum mucosa and 10 children with chronically inflamed terminal ileum mucosa. In the diarrhea group, there were 6 children with normal mucosa and 6 children with chronically inflamed mucosa.In other disease group, there were 11 children with normal mucosa and 4 children with chronically inflamed mucosa. No differences statistically in ileum peptidase and disaccharidases activity values were observed between diarrhea group and control group. No differences statistically in ileum brush border peptidase and disaccharidases activity values were observed between normal terminal ileum mucosa and chronically inflamed terminal ileum mucosa. Conclusions The level of ileal mucosa peptidase and disaccharidases activities were not changes in persistent diarrhea and chronic diarrhea children with normal villi. There were no obvious changes in the level of peptidase and disaccharidases activities in chronically inflamed terminal ileum mucosa if the villus was normal.