Anti-pituitary antibodies in children with newly diagnosed celiac disease: a novel finding contributing to linear-growth impairment.

Objectives: The possible autoimmune involvement of the pituitary gland in patients with celiac disease (CD) has been suggested but demonstrated in only a few patients on gluten-free diet. We aimed to assess the prevalence and clinical meaning of anti-pituitary antibodies (APA) in children and adolescents with the newly diagnosed CD.

Methods: A total of 119 patients with CD (0.9-15.8 years old) attending the inpatient clinic of University Hospital were recruited for the cross-sectional study. Their height, weight, and body mass index (BMI) were recorded, and insulin-like growth factor-1 (IGF-1) and APA were assayed. APA was also determined in 98 sex- and age-matched controls.

Results: APA were detected in 50 patients (42.0%), 15 of them with high titer (30%) and 35 with low titer (70%), and in 2 control subjects at low titer (2%) (P<0.001). IGF-1 was higher in patients with negative than with low titer (P=0.02) or high titer APA (P=0.03). Height was more reduced in high-titer APA patients than in the negative ones (P<0.01). Height was positively correlated with IGF-1 (P<0.01) and negatively with chronological age (P=0.001). IGF-1 was positively correlated with BMI (P<0.001). For height prediction the regression analysis showed the rank order 1 for chronological age and 2 for IGF-1.

Conclusions: In this paper we have shown a remarkable prevalence of positive APA in newly diagnosed CD patients. High APA titers are associated with height impairment, likely mediated by a reduction of IGF-1, thus suggesting that autoimmune pituitary process could induce a linear-growth impairment.