Hamlet A, Thoreson A C, Nilsson O, Svennerholm A M, Olbe L
Centre for Gastroenterological Research, Sahlgrenska University Hospital, Göteborg, Sweden.
Gastroenterology. 1999 Feb;116(2):259-68. doi: 10.1016/s0016-5085(99)70121-6.
BACKGROUND & AIMS: It is unclear why only a minority of subjects infected by Helicobacter pylori develop duodenal ulcers (DU). The aim of this study was to investigate whether the number and type of H. pylori strains in the duodenum of patients with DU may play a critical role.
Twenty-one patients with DU and 20 asymptomatic subjects with antral H. pylori infection were studied. Paired biopsy specimens were taken from the antrum and from each quadrant of the duodenal bulb. Analyses included extent of duodenal gastric metaplasia, severity of duodenitis, bacterial density, presence of the cagA gene, and vacuolating cytotoxin activity.
H. pylori was cultured from duodenal biopsy specimens in 95% of patients with DU and 80% of asymptomatic subjects. Both groups had a similar bacterial density and proportion of cagA-positive strains in the antrum (86% vs. 75%), but patients with DU had a 20-fold higher density of H. pylori and a higher proportion of cagA-positive strains in the duodenal bulb (81% vs. 30%). Active duodenitis was present only in patients with DU infected by cagA positive strains in the duodenum.
The results suggest that a high density of cagA-positive strains in the duodenum with severe duodenitis are important determinants of DU disease.
目前尚不清楚为何仅有少数幽门螺杆菌感染患者会发生十二指肠溃疡（DU）。本研究旨在探讨DU患者十二指肠中幽门螺杆菌菌株的数量和类型是否可能起关键作用。
对21例DU患者和20例无症状胃窦幽门螺杆菌感染受试者进行研究。从胃窦和十二指肠球部的每个象限获取配对活检标本。分析包括十二指肠胃化生程度、十二指肠炎严重程度、细菌密度、cagA基因的存在情况以及空泡毒素活性。
95%的DU患者和80%的无症状受试者的十二指肠活检标本中培养出幽门螺杆菌。两组在胃窦中的细菌密度和cagA阳性菌株比例相似（86%对75%），但DU患者十二指肠球部的幽门螺杆菌密度高20倍，cagA阳性菌株比例更高（81%对30%）。仅在十二指肠中感染cagA阳性菌株的DU患者中存在活动性十二指肠炎。
结果表明，十二指肠中cagA阳性菌株的高密度与严重的十二指肠炎是DU疾病的重要决定因素。
