Endocrine Abstracts

Congenital morphological thyroid abnormalities can be classified as hemiagenesis or total agenesis, lingual thyroid, substernal thyroid, thyroglossal ductus remnant. Hemiagenesis with absence of one lobe or lobe and isthmus is very rare, it was found in 4 of 7000 scans in one study. The left lobe is absent four times as often as the right lobe, and women are about three times more likely than men to have this developmental defect. Usually diagnosing this condition is not very easy, because it can be confused with a hyperfunctioning thyroid nodule with a marked suppression of all other thyroid tissue. Generally it presents with symptoms of hyperthyroidism, but hypothyroidism or euthyroidism can also be observed. Our 18 year old female patient presented with symptoms of palpitation, dysphagia, insomnia. On physical examination her thyroid was palpable. She had no neck or thyroid operation in the history. Laboratory data revealed euthyroidism, thyroglobuline antibody and thyroid peroxidase antibody testing were all negative. Ultrasonography revealed left lobe and isthmus agenesis, enlargement of the right lobe with multiple cystic nodules in different sizes. Scintiscan findings with technetium Tc 99 m pertechnetate also showed left lobe and isthmus agenesis. We wanted to report this condition because of its rare occurence and diagnostic problems. Generally it is diagnosed when there are other thyroid abnormalities. In the patients who have unilateral radionuclide uptake on the scintiscan, a doppler ultrasonography of all the thyroid tissue must be performed for to prevent the futile therapeutic interventions.