Department of Clinical and Experimental Medical Sciences, Unit of Pediatrics, University Hospital of Udine, Piazzale S. Maria Misericordia 1, 33100, Udine, Italy.
Department of Laboratory Medicine, Institute of Clinical Pathology, University Hospital of Udine, Udine, Italy.
Ital J Pediatr. 2017 Aug 10;43(1):70. doi: 10.1186/s13052-017-0392-6.
The onset of coeliac disease (CD) in the first year of life is uncommon and the diagnosis can be challenging due to the suboptimal sensitivity of tissue transglutaminase antibodies (tTG) at this age and the many other possible causes of malabsorption in infants. Antibodies to deamidated gliadin peptides (anti-DGPs), especially IgG, may appear earlier than IgA anti-tTG in very young children with CD.
We report here on an 8-month-old child who was evaluated for failure to thrive, constipation and developmental delay. The symptoms started following gluten introduction in the diet. Laboratory tests showed high fecal elastase concentration, normal serum IgA levels with positive IgG and IgA anti-DGPs, whereas anti-tTG were not detected. The duodenal biopsy revealed a complete villous atrophy (Marsh-Oberhuber 3C). The culture of biopsy fragments in the presence of gliadin peptides did not stimulate the production of IgA anti-endomysial antibodies. Genetic testing proved the child was positive for HLA-DQ2 (DQA105; DQB102) and HLA-DQ8 (DQA103, DQB10302). Having initiated the gluten-free diet, the symptoms disappeared and the infant experienced rapid catch-up growth with normalization of psychomotor development.
This case report highlights the utility of anti-DGPs for screening infants with suspected CD. The pattern with positivity for IgG and IgA anti-DGPs only is rare in IgA-competent children with biopsy-proven CD. It could be explained in infancy as immaturity of the adaptive immune system.
乳糜泻（CD）在生命的第一年发病并不常见，由于该年龄段组织转谷氨酰胺酶抗体（tTG）的敏感性不足，以及婴儿吸收不良的许多其他可能原因，诊断具有挑战性。抗脱酰胺麦胶蛋白肽抗体（抗-DGPs），尤其是 IgG，可能在非常年幼的 CD 儿童中比 IgA 抗 tTG 更早出现。
我们在此报告一例 8 个月大的患儿，因生长不良、便秘和发育迟缓而就诊。症状始于饮食中引入麸质后。实验室检查显示粪便弹性蛋白酶浓度高，血清 IgA 水平正常，IgG 和 IgA 抗-DGPs 阳性，而抗 tTG 未检出。十二指肠活检显示绒毛完全萎缩（Marsh-Oberhuber 3C）。在存在麦胶肽的情况下培养活检片段并未刺激 IgA 抗内肌层抗体的产生。基因检测证实患儿 HLA-DQ2（DQA105；DQB102）和 HLA-DQ8（DQA103，DQB10302）阳性。开始无麸质饮食后，症状消失，婴儿迅速赶上生长，精神运动发育正常。
本病例报告强调了抗-DGPs 用于筛查疑似 CD 婴儿的效用。在活检证实的 CD 患儿中，仅有 IgG 和 IgA 抗-DGPs 阳性的模式很少见。在婴儿期可能是适应性免疫系统不成熟的原因。
