Serum concentrations of anti-thyroid peroxidase and anti-thyroglobulin antibodies in children and adolescents without apparent thyroid disorders

Abstract

ObjectiveThe age-dependent prevalence and clinical relevance of anti-thyroid peroxidase (TPOAb) and anti-thyroglobulin (TGAb) antibodies in children and adolescents without thyroid diseases are unknown. The aim of this study was to measure the concentration of these thyroid autoantibodies in a large cohort of hospitalized and out-patient subjects. Additionally, we investigated the correlation of TPOAb and TGAb with thyroid parameters as well as with putative confounding parameters such as standard deviation scores (SDS) of height, BMI–SDS and CRP. MethodsSerum samples from 841 patients with non-thyroid related diseases between 1day post partum and 20years of age were used in a cross-sectional study. TPOAb, TGAb, thyroid parameters (TSH, fT3, fT4 and thyroglobulin) and CRP were measured by the Modular System (Roche, Mannheim). ResultsThe values of TPOAb and TGAb showed an age-dependent maximum of antibody frequency for both genders during the first year of life with concentrations of 163IU/mL and 161IU/mL in the 95th percentile. In girls, a second maximum was observed during puberty with concentrations of 82IU/mL TPOAb and 582IU/mL TGAb in the 95th percentile. Both antibodies correlated significantly (p<0.05) with each other, with fT3, fT4, BMI–SDS (only TPOAb) and CRP and TSH (only TGAb). ConclusionThe prevalence of TPOAb and TGAb was shown to be age-dependent with increased values in the first year of life and during puberty. The increased “physiological” concentrations of TPOAb and TGAb have to be considered when used as diagnostic indicators of autoimmune thyroid disease in a paediatric population.