Tveito Kari, Hetta Anne Kristine, Askedal Mia, Brunborg Cathrine, Sandvik Leiv, Løberg Else Marit, Skar Viggo
Department of Medicine, Lovisenberg Diakonale Hospital, Lovisenberggata 17, Oslo, Norway.
Scand J Gastroenterol. 2009;44(7):813-9. doi: 10.1080/00365520902846233.
The H(2)-sorbitol breath test (H(2)-SBT) has previously been suggested as a screening tool for coeliac disease. We developed an alternative (13)C-sorbitol breath test ((13)C-SBT). The aim of the study was to compare the diagnostic properties of the H(2)-SBT and the (13)C-SBT in a clinical setting.
Thirty-nine coeliac patients, 40 patient controls (mainly patients with irritable bowel syndrome) and 26 healthy volunteers underwent the breath tests. The patients were given an oral load of 5 g sorbitol and 100 mg (13)C-sorbitol dissolved in 250 ml tap-water. H(2), CH(4) and (13)CO(2) concentrations were measured in end-expiratory breath samples every 30 min for 4 h. Increased H(2) concentration > or =20 ppm from basal values was used as the cut-off for the H(2)-SBT.
The H(2)-SBT had a sensitivity of 71%, a specificity of 46% versus healthy controls, and a specificity of 25% versus patient controls. Individuals with methane-producing intestinal flora had significantly lower peak H(2) concentrations than non-methane producers. The (13)C-SBT reached maximal combined sensitivity/specificity (74%/85%) for both control groups after 1 h. A diagnostic algorithm which stratified patients into high-, moderate- and low risk for coeliac disease was proposed. Following the algorithm, 62% of coeliac patients were detected with 100% specificity. The (13)C-SBT, but not the H(2)-SBT, correlated with age and serum IgA tissue-transglutaminase antibody levels in coeliac patients.
The novel (13)C-SBT has superior diagnostic properties compared to the H(2)-SBT, which has unsatisfactory specificity in clinical practice. The 1-h (13)C-SBT may be a useful supplemental test when investigating for coeliac disease.
氢-山梨醇呼气试验(H(2)-SBT)此前被提议作为乳糜泻的筛查工具。我们开发了一种替代的碳-13-山梨醇呼气试验((13)C-SBT)。本研究的目的是在临床环境中比较H(2)-SBT和(13)C-SBT的诊断特性。
39例乳糜泻患者、40例患者对照(主要为肠易激综合征患者)和26名健康志愿者接受了呼气试验。给患者口服5克山梨醇和100毫克碳-13-山梨醇,溶于250毫升自来水中。在4小时内,每隔30分钟测量一次终末呼气样本中的氢气(H(2))、甲烷(CH(4))和二氧化碳-13((13)CO(2))浓度。氢气浓度较基础值升高≥20 ppm被用作H(2)-SBT的临界值。
H(2)-SBT对健康对照的敏感性为71%,特异性为46%;对患者对照的特异性为25%。肠道菌群能产生甲烷的个体,其氢气峰值浓度显著低于不产生甲烷的个体。(13)C-SBT在1小时后对两个对照组均达到最大综合敏感性/特异性(74%/85%)。提出了一种将患者分为乳糜泻高、中、低风险的诊断算法。按照该算法,62%的乳糜泻患者被检测出,特异性为100%。在乳糜泻患者中,(13)C-SBT与年龄和血清IgA组织转谷氨酰胺酶抗体水平相关,而H(2)-SBT则不然。
新型的(13)C-SBT与H(2)-SBT相比具有更优的诊断特性,H(2)-SBT在临床实践中的特异性不尽人意。1小时的(13)C-SBT在调查乳糜泻时可能是一种有用的补充检测方法。