BMC PEDIATR：乳糜泻与婴儿感染有关

　　瑞典Umea大学的Anna Myleus博士及其同事发现，2岁以下婴幼儿的感染可能与乳糜泻风险增加有关。这项研究发表在BMC PEDIATR杂志12月19日在线版上。

　　“这项研究提示，幼儿时期反复发生感染会增加今后罹患乳糜泻的风险。而且我们发现，幼儿时期感染与每日麸质摄入量之间存在协同效应，在开始摄入麸质之前已停止母乳喂养的婴幼儿中这一现象尤其明显。”

　　据研究者介绍，1984~1996年期间瑞典2岁以下幼儿的乳糜泻患病率增加了3倍，此后又出现了下降。“流行趋势变化背后的原因仍不完全清楚”，研究者猜测与感染有关：肠胃炎会增加肠道渗透率，从而增加麸质透出肠道的几率，可能导致乳糜泻风险增高。

　　研究者将2岁前被诊断为乳糜泻的婴幼儿病例与来自全国人口登记的随机匹配对照者进行了对比。

　　病例均在1992~1995年期间获得诊断，全国人口登记覆盖了40%的瑞典儿童人群。研究者利用量表采集乳糜泻病例与对照者的信息，包括家庭特征、婴儿喂养和儿童总体健康情况。最终分析纳入了954名资料完整的儿童，包括373例乳糜泻患儿和581名对照者。

　　分析结果显示，在出生后6个月内发生至少3次感染(不论感染类型如何)，与今后罹患乳糜泻的风险显著增加有关。即使校正婴儿喂养与社会经济地位之后，二者仍然存在关联[比值比(OR)，1.5；95%置信区间(CI)，1.1~2.0；P=0.009]。不仅如此，

　　研究者观察发现，假如婴幼儿在停止母乳喂养之后开始大量摄入膳食麸质，则与摄入少量麸质者相比罹患乳糜泻的风险增加4倍以上(OR，5.6；95%CI，3.1~10；P＜0.001)。

　　研究者指出，并未发现父母报告的肠胃炎与乳糜泻风险增加有关，这可能是因为发生该感染的病例数过少。不过，基于非肠胃炎感染的研究结果提示，不论发生部位如何，感染确实会影响乳糜泻风险，尽管其分子机制仍有待探索。研究者推测，感染引起的微生物群改变可能诱发免疫系统和黏膜屏障变化，从而促进乳糜泻的发生。此外，抗生素可能也起到了一定作用。

　　研究作者无相关利益冲突披露。

Early infections are associated with increased risk for celiac disease: an incident case-referent study

Background

Celiac disease is defined as a 'chronic small intestinal immune-mediated enteropathy precipitated by exposure to dietary gluten in genetically predisposed individuals'. Sweden has experienced an "epidemic" of celiac disease in children below two years of age. Celiac disease etiology is considered multifactorial; however, little is known regarding potential risk- or protecting factors. We present data on the possible association between early infectious episodes and celiac disease, including their possible contribution to the Swedish celiac disease epidemic.

Methods

A population-based incident case-referent study (475 cases, 950 referents) with exposure information obtained via a questionnaire (including family characteristics, infant feeding, and the child's general health) was performed. Celiac disease cases were diagnosed before two years of age, fulfilling the diagnostic criteria of the European Society for Pediatric Gastroenterology, Hepatology and Nutrition. Referents were randomly selected from the national population register after fulfilling matching criteria. The final analyses included 954 children, 373 (79%) cases and 581 (61%) referents, with complete information on main variables of interest in a matched set of one case with one or two referents.

Results

Having three or more parental-reported infectious episodes, regardless of type of infection, during the first six months of life was associated with a significantly increased risk for later celiac disease, and this remained after adjusting for infant feeding and socioeconomic status (odds ratio [OR] 1.5; 95% confidence interval [CI], 1.1-2.0; P=0.014). The celiac disease risk increased synergistically if, in addition to having several infectious episodes, infants were introduced to dietary gluten in large amounts, compared to small or medium amounts, after breastfeeding was discontinued (OR 5.6; 95% CI, 3.1-10; P<0.001).

Conclusion

This study suggests that having repeated infectious episodes early in life increases the risk for later celiac disease. In addition, we found a synergistic effect between early infections and daily amount of gluten intake, more pronounced among infants for whom breastfeeding had been discontinued prior to gluten introduction. Regarding contribution to the Swedish celiac disease epidemic, which partly was attributed to concurrent changes in infant feeding, early infections probably made a minor contribution via the synergistic effect with gluten amount.