儿童幽门螺杆菌感染的家庭聚集现象的研究──附60户检测结果分析

The study of intrafamilial clustering of Helicobacter pylori infection in children.

目的:探讨广西儿童幽门螺杆菌(Hp)感染的可能途径。方法:采用聚合酶链反应-限制性片段长度多态性(PCR-RFLP)方法分析60户家庭133例样本伴有上消化道症状的儿童及其一级亲属唾液和胃黏膜中的Hp尿素酶C(UreC)基因,比较两种限制性核酸内切酶HhaⅠ与AluⅠ酶切复合类型(RFLP-C),评价儿童获得Hp的可能途径。结果:在调查的60户中,儿童与其亲属Hp感染或非感染状态一致者占49户(82%),感染状态不一致者占11户(18%),P<0.001。从78个Hp阳性的家庭成员中共确定22个独立的Hp酶切类型。从25%(7/28)Hp阳性儿童、33%(10/30)Hp阳性亲属的唾液扩增出Hp,唾液与相应胃黏膜中的HpRFLP-C酶切类型一致。92%(67/73)胃体与胃窦Hp的RFLP-C类型一致。84%(26/31)先证者感染的Hp与其亲属感染的Hp类型相同,16%(5/31)与亲属的Hp类型不同。结论:PCR-RFLP分析HpUreC基因的酶切类型分辨率较高,扩增样本方法简便,适用于Hp的流行病学研究。Hp感染患者唾液与胃黏膜中扩增出的HpUreC基因RFLP-C酶切类型完全一致,同一家庭内感染的HpUreC基因RFLP类型高度相符,提示家庭内成员的口-口传播可能是儿童期获得Hp的重要模式。

Objective:To explore the possible source and tr ansmission route of Helicobacter pylori(Hp )within family mem-bers.Methods :Polymerase chain reaction-restric tion fragment length polymorphism(PCR-RFLP)method was used to analyze gastric mucosa and saliva in 133subjects belonging to 60families.Results:Thirty-one of 60(52%,31/60)family members were in con-cordance with Hp infection,and 18of 60(30%,18/60)families were in concordance withou t Hp infection.On the contrast,only7of 60families(12%,7/60)and 4of 60(7%,4/60)families were in disagreement with o r without Hp infection.Analysis of the PCR-RFLP patterns revealed that22distinct RFLP types was detected i n 78Hp-positive family members.Hp w as detected in saliva by PCR in 7of 28infected child ren(25%)and 10of 30infected relatives(33%)and their RFLP digest patterns in saliva and gastric mucosa were identical.S ixty-seven of 73specimens(92%)yielded identical digest patterns f rom the specimens from antrum and corpus,indicating that multiple strains of Hp infection was uncommon in this series.Twenty-six of 31(84%)infected children with their relatives share d identical digest patterns of Hp.Conclusion:PCR-RFLP provides a useful ,reliable,reproducible and highly discriminatory typing sc heme for epidemiological study of Hp infection;The high concordance of Hp genotypes among in-trafamilial members indicates that oral-oral transmission within fami ly members may be the most common way f or children infected with Hp in Southern China.[