Prevalence of autoantibodies associated with thyroid and Celiac disease in Ullrich-Turner syndrome in relation to adult height after growth hormone treatment

A prospective, multicenter study of patients with Ullrich-Turner syndrome (UTS) was conducted to estimate the prevalence of autoantibodies to tissue transglutaminase (tTg), thyroid stimulating hormone receptor (TSH-R), thyroglobulin (TG) and thyroid peroxidase (TPO) in relation to adult height after long-term growth hormone (GH) treatment. Out of 347 near-adult (> 16 years) patients with UTS from 96 German centers, whose longitudinal growth was documented within the Pharmacia International Growth Study (KIGS), 188 returned for a standardized follow-up visit at a median chronological age of 18.7 (16.0-23.6) years (bone age > 15 years). Serum samples of 120 patients were obtained for central measurements of TSH, thyroxine (T-4) and free T-4 and autoantibodies by standard immunoassays. Information regarding thyroid disease, karyotype and anthropometric data was extracted from the KIGS database. Thirty-six percent of the patients with UTS had positive TG and/or TPO autoantibodies and 4% had positive tTg autoantibodies, whereas 2% had positive TG and/or TPO autoantibodies as well as positive tTg autoantibodies. TSH-R autoantibodies were undetectable in all patients. The detection of autoantibodies was unrelated to a specific karyotype. Median height standard deviation scores (SDS, UTS) at start of GH treatment (0.43; -1.07, 1.85) and at follow-up (1.36; -0.11, 2.57) were comparable in all patients independent of their antibody status. The total Delta height SDS, however, was higher in patients with negative autoantibody titers (1.08; -0.03, 2.25) compared to those with positive antibody titers (0.68; -0.44, 1.82; p < 0.01). Our study confirms the high prevalence of autoantibodies in patients with UTS predisposing them to autoimmune thyroid disease and celiac disease, and indicates for the first time that autoimmune pathologies may interfere with GH therapy and thus compromise final height. Therefore, medical care for patients with UTS should routinely include screening for these autoimmune disorders in order to assure early detection and appropriate treatment.