BACKGROUND: Thyroid hemiagenesis (TH) is a rare congenital abnormality of the thyroid gland, characterised by the absence of one lobe. The true prevalence of this congenital abnormality is not known because the absence of one thyroid lobe usually does not cause clinical symptoms by itself. This study aims to identify the frequency of TH and associated diseases in outpatients referred to our clinic for the first time. SUBJECTS AND METHODS: 6242 outpatients, who were referred to our thyroid clinic between January 2008 and March 2009 and underwent thyroid ultrasonography, were retrospectively analysed. For patients with TH, demographic data, family history of thyroid disorders, drugs administered, thyroid function parameters, thyroid autoantibodies were examined and thyroid sonography was carried out. Tc99m pertechnetate scintigraphy was performed to confirm the diagnosis of hemiagenesis and to rule out coexisting ectopic thyroid tissue. RESULTS: We identified 10 cases of TH in 6242 outpatients with various thyroid disorders, 8 women and 2 men (ratio 4:1), age 21-63 years, indicating a prevalence of 0.16%. Associated thyroid disease in these patients included: 1 patient with nodular Graves' disease, 1 with Hashimoto's thyroiditis, 4 with euthyroid nodular goiters and 2 with euthyroid multinodular goiters. Nine patients were clinically asymptomatic. However, the patient with nodular Graves' disease presented thyrotoxicosis. CONCLUSIONS: TH is a rare congenital anomaly and prevalence of TH in thyroid patients is 0.16%. In our study, the most frequently seen thyroid disease accompanying thyroid hemiagenesis was nodular goiter.
BACKGROUND:Thyroid hemiagenesis (TH) is a rare congenital abnormality of the thyroid gland, characterised by the absence of one lobe. The true prevalence of this congenital abnormality is not known because the absence of one thyroid lobe usually does not cause clinical symptoms by itself. This study aims to identify the frequency of TH and associated diseases in outpatients referred to our clinic for the first time. SUBJECTS AND METHODS: 6242 outpatients, who were referred to our thyroid clinic between January 2008 and March 2009 and underwent thyroid ultrasonography, were retrospectively analysed. For patients with TH, demographic data, family history of thyroid disorders, drugs administered, thyroid function parameters, thyroid autoantibodies were examined and thyroid sonography was carried out. Tc99m pertechnetate scintigraphy was performed to confirm the diagnosis of hemiagenesis and to rule out coexisting ectopic thyroid tissue. RESULTS: We identified 10 cases of TH in 6242 outpatients with various thyroid disorders, 8 women and 2 men (ratio 4:1), age 21-63 years, indicating a prevalence of 0.16%. Associated thyroid disease in these patients included: 1 patient with nodular Graves' disease, 1 with Hashimoto's thyroiditis, 4 with euthyroid nodular goiters and 2 with euthyroid multinodular goiters. Nine patients were clinically asymptomatic. However, the patient with nodular Graves' disease presented thyrotoxicosis. CONCLUSIONS:TH is a rare congenital anomaly and prevalence of TH in thyroid patients is 0.16%. In our study, the most frequently seen thyroid disease accompanying thyroid hemiagenesis was nodular goiter.