Evans Kate E, Leeds John S, Sanders David S
Gastroenterology & Liver Unit, Royal Hallamshire Hospital, Sheffield.
Practitioner. 2009 Oct;253(1722):19-22, 2.
Recent population studies show that coeliac disease affects around 1 in 100 people. The estimated ratio of diagnosed to undiagnosed individuals is 1:8, and the average delay in diagnosis is reported to be 11 years. The contemporary coeliac patient is diagnosed between the ages of 40 and 60, has normal or even high BMI, and subtle symptoms. Patients are often identified in screening groups which would include those with type 1 diabetes, autoimmune thyroid disease, or a first-degree relative with coeliac disease. The presence of relevant symptoms is not essential for a diagnosis of coeliac disease. Additionally, positive serological testing alone is not sufficient to confirm the diagnosis. Endomysial antibody (EMA) and tissue transglutaminase (TTG) have a combined sensitivity and specificity of > 90% when used in combination in selected populations. However, false positives occur in conditions such as inflammatory bowel disease, and autoimmune disease. Conversely antibody-negative disease accounts for around 9% of cases. IgA deficiency is a cause of false negatives and levels should be checked at the same time as EMA and TTG. Patients must consume a gluten-containing diet for six weeks before serological testing and biopsy if necessary. All those with positive serological tests, and those for whom clinical suspicion is high even if seronegative, should be referred to a gastroenterologist for a duodenal biopsy to confirm or exclude coeliac disease. Diagnosis requires the demonstration of villous atrophy in the small bowel which improves when gluten is withdrawn.
近期的人口研究表明，乳糜泻影响着约每100人中的1人。据估计，已确诊与未确诊个体的比例为1:8，据报道平均诊断延迟为11年。当代乳糜泻患者在40至60岁之间被诊断出来，体重指数（BMI）正常甚至偏高，且症状不明显。患者通常在筛查群体中被发现，这些群体包括1型糖尿病患者、自身免疫性甲状腺疾病患者或有乳糜泻的一级亲属。出现相关症状对于乳糜泻的诊断并非必要条件。此外，仅血清学检测呈阳性不足以确诊。在特定人群中联合使用时，肌内膜抗体（EMA）和组织转谷氨酰胺酶（TTG）的联合敏感性和特异性>90%。然而，在炎症性肠病和自身免疫性疾病等情况下会出现假阳性。相反，抗体阴性的病例约占9%。IgA缺乏是假阴性的一个原因，应在检测EMA和TTG的同时检查其水平。必要时，患者在进行血清学检测和活检前必须食用含麸质饮食六周。所有血清学检测呈阳性的患者，以及即使血清学检测阴性但临床怀疑度高的患者，都应转诊至胃肠病学家处进行十二指肠活检，以确诊或排除乳糜泻。诊断需要证明小肠绒毛萎缩，在去除麸质后会有所改善。
