Department of Gastroenterology, Hospital Universitari Mutua Terrassa, University of Barcelona, Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas-CIBERehd, Terrassa, Barcelona, Spain.
J Crohns Colitis. 2012 Sep;6(8):861-6. doi: 10.1016/j.crohns.2012.01.016. Epub 2012 Feb 15.
It has been suggested that high titres of tTG are associated with elevated positive predictive values (PPV) for celiac disease. However, the PPV of a strongly positive tTG will depend on the celiac disease prevalence in the different risk groups of the disease
To assess the PPV of a strongly positive tTG for celiac disease. In addition, to calculate the post-test probability for celiac disease of a strongly positive tTG in a setting of routine clinical practice.
145 consecutive celiac disease patients with positive tTG, and with a small bowel biopsy were included. The PPV for different cut-off points of tTG levels for the diagnosis of celiac disease was assessed. In addition, the cut-offs associated with higher PPV were used to calculate the positive likelihood ratio. A simulation in a setting of routine clinical practice was performed to calculate the post-test probability of celiac disease.
No cut-off level was associated with a PPV of 100%. A cut-off of 80 U/mL (11.4×upper normal limit) was associated with the higher PPV value of 98.6%. In the most frequent clinical situations, which in general have a pre-test probability <10%, the post-test probability after having a strongly positive tTG was 90% or less.
A strongly positive tTG should not be enough to diagnose celiac disease in the most frequent clinical situations, small bowel biopsy remaining as the gold standard in these cases.
已有研究表明，抗组织转谷氨酰胺酶（tTG）抗体滴度较高与乳糜泻的阳性预测值（PPV）升高有关。然而，强阳性 tTG 的 PPV 将取决于不同疾病风险组的乳糜泻患病率。
评估强阳性 tTG 对乳糜泻的 PPV。此外，在常规临床实践中计算强阳性 tTG 对乳糜泻的患病后概率。
纳入 145 例 tTG 阳性且小肠活检阳性的乳糜泻患者。评估不同 tTG 水平截断值对乳糜泻诊断的 PPV。此外，使用与较高 PPV 相关的截断值计算阳性似然比。在常规临床实践中进行模拟，以计算乳糜泻的患病后概率。
没有截断值与 100%的 PPV 相关。80 U/mL（正常值上限的 11.4 倍）的截断值与 98.6%的较高 PPV 值相关。在最常见的临床情况下，一般来说，患病前概率<10%，在强阳性 tTG 后患病后概率<90%。
在最常见的临床情况下，强阳性 tTG 不足以诊断乳糜泻，在这些情况下，小肠活检仍然是金标准。
