title: Does TSH Trigger the Anti-thyroid Autoimmune Processes? Observation on a Large Cohort of Naive Patients with Thyroid Hemiagenesis.
abstract: Thyroid hemiagenesis (THA) is a rare abnormality characterized by the absence of one thyroid lobe. Elevated thyroid stimulating hormone (TSH) level and higher incidence of thyroid diseases were reported in THA. The aim of the study is to evaluate the thyroid autoimmunity incidence in patients with THA and influence of higher than average TSH level on thyroid volume (TV) and its change with age. The study included a group of naive patients with THA and a control group of subjects with bilobate thyroid. All patients underwent clinical examination, thyroid ultrasound, scintiscan and laboratory tests. In the studied and control group the presence of thyroid autoantibodies (TAb) was evaluated. The THA group consisted of 65 patients. In THA group 53.85 % of patients were positive for TAb. Patients with positive TAb were older (46.0 ± 18.3 years) than those with negative (35.0 ± 19.8 years); p = 0.02. The incidence of TAb was lower in controls (13.85 %, p < 0.0001). In the study group, positive correlation between the age and TV (r = 0.46, p = 0.0001), and negative correlations between the age and TSH level (r = -0.31, p = 0.01), and TSH concentration and TV (r = -0.35, p = 0.004) were found. In a subgroup of 30 patients with THA negative for TAb, even stronger correlations were observed. The median single lobe volume and median TSH level were higher in patients with THA when compared to controls (13.60 vs 8.20 ml, p < 0.0001; 3.23 vs 1.48 µU/ml, p < 0.0001, respectively). Patients with THA constitute an in vivo model of long-term thyroid TSH overstimulation. Further studies are needed to reveal, whether TSH overstimulation may be the trigger for thyroid autoimmunity.
authors.affiliation: Department of Endocrinology, Metabolism and Internal Medicine, Poznan University of Medical Sciences, Przybyszewskiego 49, 60-355, Poznan, Poland.
authors.forename: Ewelina
authors.initials: E
authors.lastname: Szczepanek-Parulska
authors.affiliation: Department of Endocrinology, Metabolism and Internal Medicine, Poznan University of Medical Sciences, Przybyszewskiego 49, 60-355, Poznan, Poland.
authors.forename: Ariadna
authors.initials: A
authors.lastname: Zybek-Kocik
authors.affiliation: Department of Endocrinology, Metabolism and Internal Medicine, Poznan University of Medical Sciences, Przybyszewskiego 49, 60-355, Poznan, Poland.
authors.forename: Kosma
authors.initials: K
authors.lastname: Woliński
authors.affiliation: Department of Biochemistry and Molecular Biology, Center of Postgraduate Medical Education, Warsaw, Poland.
authors.forename: Barbara
authors.initials: B
authors.lastname: Czarnocka
authors.affiliation: Department of Endocrinology, Metabolism and Internal Medicine, Poznan University of Medical Sciences, Przybyszewskiego 49, 60-355, Poznan, Poland. mruchala@ump.edu.pl.
authors.forename: Marek
authors.initials: M
authors.lastname: Ruchała
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001323:Autoantibodies / Q000276:immunology*; D016022:Case-Control Studies; D002648:Child; D015331:Cohort Studies; D005260:Female; D006042:Goiter / Q000276:immunology; D006801:Humans; D008297:Male; D008875:Middle Aged; D013961:Thyroid Gland / Q000276:immunology*; D013963:Thyroid Hormones / Q000378:metabolism; D013972:Thyrotropin / Q000276:immunology*; D055815:Young Adult
chemical_list: D001323:Autoantibodies; D013963:Thyroid Hormones; D013972:Thyrotropin
keywords: Autoimmunity; Hormone secretion; Nodular goiter; Thyroid