Celiac disease (CD) is a gluten-sensitive enthesopathy occurring in genetically predisposed individuals that is caused by a permanent intolerance to gluten. The major environmental factor associated with the risk of developing celiac-related complications is persistent exposure to dietary gluten. The aim of this study was to determine the prevalence of lower limb enthesopathy in CD patients at first diagnosis compared with CD patients on a gluten-free diet (GFD). Fifty-five untreated CD patients (group A) and 55 CD patients on a GFD from at least 1 year (group B), matched for age and sex, attending gastroenterology outpatient clinic of the University Federico II of Naples, were enrolled in this study. All patients underwent clinical and ultrasonography examination. Among group A, 27 (49.8 %) patients presented at least one entheseal alteration as compared with 15 patients (27.2 %) of group B (prevalence rate ratio 1.83, I.C. 95 % = 0.48-7.01; p < 0.001). The Glasgow ultrasound enthesitis scoring system (GUESS) was significantly higher in patients of group A than in patients of group B. In conclusion, our study shows that enthesopathy is more frequent in untreated CD subjects with positive anti-tissue transglutaminase antibodies title, as compared to those on GFD and absence of serum anti-tissue transglutaminase antibodies title.