The influence of gluten free diet on quantitative ultrasound of proximal phalanxes in children and adolescents with type 1 diabetes mellitus and celiac disease

A reduced bone mineral density has been reported in patients with untreated celiac disease (CD) as well as in patients with poorly controlled type 1 diabetes mellitus (T1DM). The aim of this study was to evaluate the bone mineral status by phalangeal quantitative ultrasound in 52 children and adolescents with both diseases (mean age 13.3 ± 4.9 years). As a control group 50 patients with T1DM and no CD (age 12.2 ± 4.0 years) were studied. The following bone parameters, amplitude-dependent speed of sound (AD-SoS) and bone transmission time (BTT) were considered and expressed as z score. Compliance to gluten free diet and long term glycemic control (mean of four determinations of HbA1c in the last year) were also assessed.The lowest mean AD-SoS z score values were found in patients with T1DM and CD, who reported transgressions to gluten free diet and exhibited positivity for serum anti-tissue transglutaminase antibodies (tTG) and/or endomysial antibodies (EmA), compared with patients with occasional transgressions but negative for anti-tTG and/or -EmA, patients strictly adherent to the diet, and patients who suffered only from diabetes (ANOVA p = 0.021). No difference was found between patients with diabetes alone and patients with both diseases strictly adherent to gluten free diet. Prevalence of osteopenia (z AD-SoS values < − 2 SD) was higher in patients with T1DM and CD and poor compliance to the diet (45.5%) compared with patients with T1DM (8%) or patients with both diseases strictly compliant to diet (12.9%) (p = 0.015). A negative correlation between Ad-SoS z score and HbA1c (r − 0.236, p = 0.036) was found when patients with T1DM and patients with T1DM and CD, who strictly adhere to the diet, were pooled.In conclusion the quality of bone as assessed by phalangeal ultrasound in patients with T1DM and CD, who strictly adhere to gluten free diet, is similar to that found in T1DM patients. A higher prevalence of osteopenia is present in patients with both diseases who reported habitual transgressions to gluten free diet. The gluten free diet, as well as the optimization of glycemic control, plays an important role in preventing the osteopenic status caused by the clustering of these two chronic diseases.