幽门螺杆菌菌株类型与儿童上消化道疾病的关系

Relationship between the types of Helicobacter pylori strains and chronic upper gastrointestinal diseases in children

目的幽门螺杆菌(Helicobacter pylori,Hp)感染已被确立为是引起慢性浅表性胃炎和消化性溃疡的重要病因,是胃癌和胃黏膜相关性淋巴样组织(MALT)淋巴瘤的重要危险因素。Hp的致病性与毒力有关,而细胞毒素相关蛋白(CagA)和空泡毒素(VcaA)是Hp的主要毒力因子之一。该研究通过了解Hp菌株类型与儿童胃十二指肠疾病类型及胃窦黏膜病理组织学变化的关系,探讨Hp感染的分型诊断是否有助于判断儿童胃十二指肠疾病的严重程度。方法采用免疫印迹法对115例有上消化道症状的患儿进行Hp的血清学分型,并行胃镜检查,观察胃十二指肠疾病类型。取胃窦黏膜经Harris配方苏木精染色观察胃窦黏膜病理组织学变化、亚甲基蓝染色观察Hp感染情况。结果115例患儿中检出HpⅠ型菌株84例(73.0%),中间型菌株21例(18.3%),Ⅱ型菌株10例(8.7%);Ⅰ型菌株引起胃窦黏膜中、重度炎症分别为83例、1例;中间型菌株引起胃窦黏膜中度炎症21例;Ⅱ型菌株引起胃窦黏膜轻度炎症2例,中度炎症8例,经统计学处理,各型菌株在引起胃窦黏膜炎症程度上差异有显著性(χ2=15.444,P<0.01),Ⅰ型菌株感染引起胃窦黏膜炎症程度最重,Ⅱ型菌株感染引起胃窦黏膜炎症程度最轻;而在活动性、萎缩的发生率上,各型差异无显著性(P>0.05);在淋巴滤泡形成的发生率上,各型差异有显著性(χ2=10.171,P<0.01)。各型菌株引起胃镜下胃、十二指肠疾病类型的构成比无明显差异(P>0.05)。结论该地区儿童Hp感染以Ⅰ型菌株最为多见。各型菌株100%存在胃窦黏膜组织学改变。Ⅰ型菌株感染所致胃窦黏膜炎症程度最重,且引起淋巴滤泡形成的发生率最高。Hp感染的分型诊断无助于对儿童胃、十二指肠疾病类型的判断,但有助于对儿童胃、十二指肠疾病病情的判断,Ⅰ型菌株感染者需要更为积极的治疗,对于Hp感染的儿童无论其血清分型如何,均应引起重视,并长期随访。

Objective To study the relationship of the types of Helicobacter pylori （ H. pylori） strains with the classification and the severity of chronic gastro-duodenal diseases in children. Methods One hundred and fifteen children with chronic upper gastrointestinal symptoms who were diagnosed as H. pylori infection by gastroscopy were enrolled in this study. H. pylori strains were serotyped by immunoblot technique. The gastric biopsy specimens of all patients were studied histologically. Results Type I H. pylori strains were confirmed in 84 cases （ 73.0% ）, intermediate type strains in 21 cases （18.3%）, and type II strains in 10 cases （8.7%）. Type I H. pylori strains infection caused a moderate gastric mucosal inflammation in 83 cases and a severe inflammation in 1 case. Intermediate type H. pylori strains infection caused a moderate gastric mucosal inflammation in 21 cases. Type Ⅱ H. pylori strains infection caused a mild gastric mucosal inflammation in 2 cases and a moderate inflammation in 8 cases. Different types of H. pylori strains resulted in different severity of gastric mucosal inflammation （ X^2 = 15. 444, P 〈 0.01 ）. The gastric mucosal inflammation due to type Ⅰ H. pylori strains was the most severe, while the inflammation due to type II H. pylori strains was relatively mild. The incidence of nodulus lymphaticus of gastric mucosa due to type I, type II and intermediate type H. pylori strains infection was 76.2%, 47.6% and 40.0%, respectively（X^2 = 10. 171, P 〈 0.01 ）. The classification of chronic gastro-duodenal diseases was not associated with the types of H. pylori strains. Conclusions Type I strains were the leading cause of H.pylori infection in children, All of types of H. pylori strains can cause pathohistologic changes of gastric mucosa, Type I H, pylori strains infection can result in the most severe gastric mucosal inflammation and the highest incidence of nodulus lymphaticus, The immunoblot serotyping of H, pylori strains may be useless for the classification of chronic upper gastrointestinal diseases but it is helpful for the evaluation of the severity of the diseases in children.