Thyroid Ultrasonography Helps to Identify Patients with Diffuse Lymphocytic Thyroiditis who Are Prone to Develop Hypothyroidism*

OBJECTIVE: Graves' disease leads to thyroid enlargement and to reduction of tissue echogenicity. Our purpose was to correlate grey scale ultrasonography of the thyroid gland with clinical and laboratory findings in patients with Graves' disease. DESIGN: Fifty-three patients with Graves'disease were included in our study, 100 euthyroid volunteers served as control group. Free thyroxine (FT(4)), TSH and TRAb (TSH receptor antibodies) values were measured and correlated with sonographic echogenicity of the thyroid gland. METHODS: All patients and control persons underwent ultrasonographical histogram analyses under standardized conditions. Mean densities of the thyroid tissues were determined in grey scales (GWE). RESULTS: Compared with controls with homogeneous thyroid lobes of normal size (25.6 +/- 2.0GWE, mean +/- S.D.) echogenicity in patients with Graves' disease was significantly lower (21.3 +/- 3. 3GWE, mean +/- S.D., P < 0.0001). Among the patients with Graves' disease significant differences of thyroid echo levels were revealed for patients with suppressed (20.4 +/- 3.1 GWE, mean +/- S.D., n=34) and normalized TSH values (22.5 +/- 3.6GWE, mean +/- S.D., n=19, P < 0.02). Significantly lower echogenicities were also measured in cases of persistent elevated TRAb levels (19.9 +/- 2.9GWE, mean +/- S.D., n=31) in comparison with normal TRAb levels (22.9 +/- 3.5 GWE, mean +/- S.D., n=22, P < 0.0015). No correlation could be verified between echogenicity and either still elevated or already normalized FT(4) values or the thyroid volume. In coincidence of hyperthyroidism and Graves' ophthalmopathy (19.7 +/- 3.5GWE, mean +/- S.D., n=23) significantly lower echogenicity was measured than in the absence of ophthalmological symptoms (22.3 +/- 3.3GWE, mean +/- S.D., n=30, P < 0.016). Patients needing active antithyroid drug treatment revealed significantly lower thyroid echogenicity (20.3 +/- 3.1 GWE, mean +/- S.D., n=40) than patients in remission (23.7 +/- 3.4 GWE, mean +/- S.D., n=13, P < 0.001). Statistical evaluation was carried out using Student's t-test. CONCLUSIONS: Standardized grey scale histogram analysis allows for supplementary judgements of thyroid function and degree of autoimmune activity in Graves' disease. Whether these values help to estimate the risk of recurrence of hyperthyroidism after withdrawal of antithyroid medication should be evaluated in a prospective study.

Section: Discussionmentioning

confidence: 99%

Standardized grey scale ultrasonography in Graves' disease: correlation to autoimmune activity

Schiemann

Gellner

Riemann

et al. 1999

“…Moreover, thyroid ultrasonography (Toshiba Nemio, 9 MHz linear transducer, with power Doppler imaging) was performed. The thyroid gland volume was estimated, and the structure was assessed for homogeneity, echogenicity and vascularity, especially valuable in cases of suspicion of chronic autoimmune thyroiditis, on a modified semiquantitative scale: 1 -normal, 2 -borderline, 3 -suspect and 4 -typical (18,19). If necessary (due to borderline screening values), the tests for screening were repeated together with further assays: free triiodothyronine (RIA, Immunotech, Beckman Coulter, RR, 2.5-5.7 pmol/l, CV, 6.4%) and Tg-Ab (RIA, Immunotech, Beckman Coulter, RR, !100 IU/ml, CV, 10.4%).…”

Section: Methodsmentioning

confidence: 99%

Universal screening detects two-times more thyroid disorders in early pregnancy than targeted high-risk case finding

Horáček¹,

Špitálníková²,

Dlabalova

et al. 2010

100

Objective: Screening of thyroid disorders in pregnancy has been controversial. Recent recommendations favour targeted high-risk case finding, though this approach may miss a significant number of those affected. We aimed to assess the prevalence of accepted high-risk criteria in women with autoimmune thyroiditis and/or hypothyroidism detected from universal screening in an iodinesufficient population. Design: In 400 non-selected women in the 9-11th gestational week, thyroid-related tests were performed, and those with abnormalities were offered consultation. Methods: TSH was determined by IRMA, and the upper cut-off value for screening was set at 3.5 mIU/l. For free thyroxine (FT 4 ) and thyroperoxidase antibodies (TPO-Ab), RIAs were used, with cut-offs of !10 pmol/l and O50 IU/ml respectively. Endocrinological consultation included Doppler ultrasonography and was aimed to confirm autoimmune thyroiditis and/or hypothyroidism. The prevalence of consensus high-risk criteria was assessed. Results: Among the 400 women, 65 (16.3%) had R1 abnormality: higher TSH was found in 10.3%, lower FT 4 in 2% and positive TPO-Ab in 8.3%. Fifty-one women were examined and followed up. Levo-T 4 treatment was initiated in 49 women for autoimmune thyroiditis (in 42), hypothyroidism (in 34) or both (in 27). Only 22 (45%) of 49 treated women fulfilled R1 high-risk criterion: most commonly family history (31%), history of miscarriage or preterm delivery (14%) and personal history (8%). Conclusions: Over half (55%) of pregnant women with abnormalities suggestive of autoimmune thyroiditis and/or hypothyroidism would be missed if only those with high-risk criteria were examined. A more extensive screening of thyroid autoimmunity and dysfunction seems warranted.

“…Over the last decade, ultrasound (US) scans proved to be a valuable tool for the diagnostic work-up of thyroid diseases (1)(2)(3)(4)(5)(6)(7)(8). Besides estimation of thyroid volume and identification of non-palpable thyroid nodules (9), US scans are able to characterize the echographic structure of thyroid tissue (10).…”

Section: Introductionmentioning

confidence: 99%

“…The interface between thyroid cells and the colloid exhibits an elevated acoustic impedance, causing high-frequency acoustic waves to be reflected back to the probe. In autoimmune thyroid diseases (AITDs), however, both lymphocytic infiltration and disruption of normal tissue architecture cause a reduction in thyroid echogenicity (1,4,6,10,11). Thyroid hypoechogenicity is currently viewed as an early sign of thyroid autoimmunity, which may be present even when the thyroid disorder is not suspected from a clinical point of view (4,6,7,12,13).…”

Section: Introductionmentioning

confidence: 99%

A hypoechoic pattern of the thyroid at ultrasound does not indicate autoimmune thyroid diseases in patients with morbid obesity

Rotondi¹,

Cappelli²,

Leporati³

et al. 2010

Objective: Thyroid ultrasound (US) scan is a valuable tool for diagnosing thyroid diseases. In autoimmune thyroid disease (AITD), an hypoechoic pattern of the thyroid at US is related to circulating thyroid antibodies (Abs). The aim of this study was to evaluate the diagnostic accuracy of thyroid US for the detection of AITD in patients with morbid obesity. Design: Thyroid US scans showing an hypoechoic pattern of the thyroid were collected from 105 morbid obese patients (body mass index (BMI) O40 kg/m 2 ) and 105 non-obese patients (BMI%30 kg/m 2 ). Results: A thyroid hypoechoic pattern at US was consistent with clinical/biochemical features of AITD in 90/105 (85.7%) non-obese patients and in 22/105 (20.9%) morbid-obese patients (P!0.0001). By performing a complete thyroid work-up, including clinical examination, thyroid morphology, serum hormones, and auto-Ab measurements, the discrepancy between the US pattern and the results of the thyroid Ab tests was justified in 6/15 non-obese patients, and only in 1/83 morbid obese patients. Thus, an unexplained hypoechoic pattern of the thyroid at US, defined as negative tests for thyroid Ab and absence of justifying thyroid disturbances, was found in 2/105 (1.9%) non-obese patients and in 68/105 (64.8%) morbid obese patients (P!0.0001). Conclusions: Our results suggest that i) morbid obesity may affect thyroid morphology, and ii) an hypoechoic pattern of the thyroid at US, a well-established parameter for diagnosing AITD, has a poor diagnostic accuracy when patients with morbid obesity are taken into account.