Ewelina Szczepanek

Increased risk of thyroid pathology in patients with thyroid hemiagenesis: results of a large cohort case-control study

OBJECTIVE Thyroid hemiagenesis (THA) is an anomaly resulting from the developmental failure of one thyroid lobe. Etiopathogenesis, clinical significance, and management of patients in whom THA is diagnosed are still a matter of debate. The aim of the study is to provide the first systematic analysis of a large cohort of subjects with THA. DESIGN Forty patients with THA are described in comparison to a control group of 80 subjects with fully developed thyroid gland. METHODS Serum concentrations of thyrotropin (TSH), free thyroxine (FT(4)), free triiodothyronine (FT(3)), and thyroid autoantibodies were measured. In 37 patients, thyroid ultrasonography and Tc-99m thyroid scintiscan were performed, followed by fine-needle aspiration biopsy if indicated. The remaining archival three cases were diagnosed with the use of I-131 scintiscan under basal conditions and after TSH stimulation. RESULTS Patients with THA, while usually clinically euthyroid, presented with significantly higher levels of TSH and FT(3) as well as with higher FT(3)/FT(4) concentration in comparison to the control group. Furthermore, a higher incidence of associated functional, morphological, and autoimmune thyroid disorders in patients with THA was observed when compared to subjects with bilobate thyroid (P<0.05). CONCLUSIONS Our results revealed that individuals with THA are more likely to develop thyroid pathology. The observed high incidence of associated pathologies is presumably due to long-lasting TSH overstimulation. Therefore, THA diagnosis should be followed by systematic observation and adequate levothyroxine treatment in patients with elevated TSH level.

Prospective echocardiographic evaluation of patients with endogenous subclinical hyperthyroidism and after restoring euthyroidism

Objectives  Clinical significance of, and the need for, treatment in subclinical hyperthyroidism (sHT) is still a matter of debate. The aim of the study was to assess the impact of sHT on echocardiographic parameters.

FOXE1 Polyalanine Tract Length Polymorphism in Patients with Thyroid Hemiagenesis and Subjects with Normal Thyroid

Background/Aims: Recent studies have pointed to the correlation between FOXE1 polyalanine tract (FOXE1-polyAla) length polymorphism and genetic susceptibility to thyroid dysgenesis causing congenital hypothyroidism. The objective of this study was a first assessment of the role of FOXE1-polyAla expansion in the genetic background of thyroid hemiagenesis (TH). Methods: The group studied consisted of 40 patients with TH, including 6 familial cases and a control group of 89 subjects with a normal thyroid. The polyAla tract and flanking sequence of FOXE1 was amplified using conventional PCR. Subsequently, capillary electrophoresis was performed to estimate the length of products. Results: A short variant of FOXE1-polyAla, containing 12 alanines, was present in 5 control subjects (5.6%), but was not found in TH. The incidence of longer variants (≧16 codons) of FOXE1-polyAla was significantly higher in patients with the familial form of TH in comparison to those with sporadic TH (p = 0.003) and controls (p = 0.005). Conclusions: There is high polymorphic variability of FOXE1-polyAla in both groups. Shorter variants of FOXE1-polyAla are underrepresented in subjects with familial TH. Therefore, FOXE1-polyAla tract expansion may contribute to the molecular background of familial but not sporadic forms of TH. Further studies are still required to confirm such findings.

The influence of subclinical hyperthyroidism on blood pressure, heart rate variability, and prevalence of arrhythmias.

BACKGROUND The impact of subclinical hyperthyroidism (sHT) on the cardiovascular system still needs to be elucidated. The aim of the study was to prospectively assess blood pressure (BP), variability in heart rate, and the prevalence of arrhythmias in patients with sHT, both before and after they are restored to the euthyroid state. METHODS The study group consisted of 44 normotensive patients (37 women, 7 men), aged 22-65 years (mean±SD: 45.9±11.0) with sHT. Enrolled patients were drawn from 1080 patients referred to our department for treatment of hyperthyroidism. Study patients were treated with radioiodine treatment to restore the euthyroid state. Ambulatory BP monitoring and Holter electrocardiography were performed (i) when sHT was diagnosed and (ii) at least 6 months after they became euthyroid. RESULTS sHT in comparison to the euthyroid state was associated with higher (109.3±7.1 vs. 107.1±7.7 mmHg) nocturnal systolic mean BP (p=0.035) and BP load (14.8 vs. 10.2%, p=0.033), mean diastolic BP (66.4±6.6 vs. 64.8±6.6 mmHg, p=0.047), and mean arterial pressure (80.8±43.1 vs. 79.3±43.6 mmHg, p=0.049). Moreover, significant changes in both the time and frequency domain measures of heart rate variability (HRV) were observed: decrease of the square root of the mean squared differences of successive NN intervals (rMSSD) (45.68±34.1 vs. 65.09±50.6 ms, p=0.03) and the low frequency power (LF) (5.71±0.99 vs. 6.0±1.01 ms(2), p=0.049) as well as increase of QT interval dispersion (58.25±28.5 vs. 46.90±12.1 ms, p=0.020). This was accompanied by a clinically insignificant increase in the frequency of ventricular extrasystoles (VES) (3.1±7.4 vs. 0.6±1.2 per hour, p=0.048) and increased mean heart rate (78.4±6.8 vs. 76.0±8.0 beats/min, p=0.004). Some of the parameters correlated positively with thyroid hormones: nocturnal diastolic BP with free triiodothyronine (FT(3)) (r=0.397, p=0.008), rMSSD with free thyroxine (FT(4)) (r=0.389, p=0.013), and QT interval dispersion with FT(4) (r=0.450, p=0.004). CONCLUSIONS The study suggests that sHT in comparison to euthyroid status may be associated with a statistically significant but probably clinically insignificant increase of QT interval dispersion, prevalence of VES, elevated nocturnal arterial BP, and changes in HRV. These findings broaden our understanding of the cardiovascular effects of sHT.

Sonoelastography in de Quervain Thyroiditis

Sonoelastography is a novel technique, providing an objective estimation of tissue elasticity by measuring the degree of distortion under the application of an external force (1). Recent studies demonstrated exceptional utility of sonoelastography in preoperative evaluation of thyroid nodules because neoplastic transformation is often associated with decreased elasticity of a lesion (1– 4). However, a sonoelastographic picture of de Quervain thyroiditis (dQT) has not yet been described. Herewithin we report cases of dQT in two women, ages 36 and 42 yr, presenting with malaise, pain in the neck, and temperature up to 38 C. Conventional ultrasonography revealed a picture typical for dQT in the first patient, but only minimal changes in the second patient, whereas sonoelastography in both demonstrated markedly decreased elasticity of the affected area (Figs. 1 and 2). Patients were euthyroid (TSH was 0.29 and 0.57 IU/ml, respectively) and had an increased erythrocyte sedimentation rate (48 and 61 mm/h, respectively). The cytological diagnosis of the specimen obtained by fine-needle biopsy was consistent with dQT. Patients were treated with ibuprofen and prednisone, which resulted in total remission. To conclude, obtained results suggest that inflammatory infiltration of thyroid parenchyma in dQT causes decreased thyroid tissue elasticity. Sonoelastography might be useful in diagnosing dQT, selecting regions for biopsy in patients with minimal changes on conventional ultrasonography, as well as in differential diagnosis with Hashimoto’s thyroiditis. Moreover, the coexistence of dQT may affect interpretation of elasticity of concomitant thyroid nodules. Studies on larger groups are required to further assess the usefulness of elastographic evaluation in dQT.

Diagnostic value of radionuclide scanning and ultrasonography in thyroid developmental anomaly imaging

Thyroid is particularly prone to morphogenetic variability. Developmental failure of the thyroid gland is in 85% of cases the underlying cause of congenital hypothyroidism, diagnosed at birth with a frequency of 1:3000-1:4000 newborns. However, the incidence of less severe developmental variants of the thyroid is much higher. Determination of the aetiology of congenital hypothyroidism is crucial for predicting its severity and outcome as well as impacts dose of L-thyroxine during substitution. Thyroid imaging is necessary to establish diagnosis, and it involves mainly thyroid ultrasound examination and scintiscan. Awareness of both the advantages and limitations of sonographic and scintigraphic imaging are central to the successful interpretation of their results and reasonable recommendation of these procedures for patients with thyroid developmental anomalies of different age and clinical picture. Hence, the aim of this review is to provide the most important and up-to-date information on the place of radionuclide scanning and ultrasonography in visualization of different thyroid developmental abnormalities.

The immunohistochemical demonstration of parafollicular cells and evaluation of calcium-phosphate balance in patients with thyroid hemiagenesis

Thyroid hemiagenesis (TH) is characterized by the congenital absence of one thyroid lobe. The aim of this study was to evaluate the calcium-phosphate balance in TH. Twenty patients with TH and 20 controls with a bilobed thyroid were studied. Serum concentrations of total calcium, parathormon and calcitonin were measured. Additionally, the immunohistochemical expression of calcitonin, chromogranin A (chA), neuron-specific enolase (NSE) and calcitonin gene-related peptide (CGRP) was evaluated in surgical specimens from patients with TH and controls. There were no significant differences in biochemical parameters between TH and controls. Positive staining for calcitonin was demonstrated in 3/8 thyroid sections from three patients with TH, but only in 2/33 sections from four controls (p < 0.005). All sections from patients with TH positive for calcitonin also expressed chA, NSE and CGRP. Two sections from controls positive for calcitonin presented an additionally positive reaction for chA, and one of them also for NSE. None presented positive staining for CGRP. Of three TH sections, in one, hyperplasia of C cells of medium grade, and in another hyperplasia of C cells of high grade, could be detected. In the controls, hyperplasia of C cells of low and medium grade was observed. TH was associated with slightly enhanced C cells hyperplasia compared to controls, which might indicate compensatory proliferation. However, the calcium-phosphate balance does not seem to be significantly affected.

Not a Graves' Situation

To physicians, it appeared that the patient surely had Graves’disease, but this was not the case. Several months before hisadmission to the Endocrinology Department, a 48-year-oldman developed rapidly growing eyelid swelling, the feeling ofhaving sand in his eyes, redness of the conjunctivae, diplopia,and photophobia. He worked as a driver, so the symptoms kepthim from his job, and made other everyday activities trulydifficult. Neither a family nor personal history revealed anythyroid disease. The patient did have a history of combinedhyperlipidemia (Table 1), which had been treated with fenofi-brate, 267 mg daily, for 8 years. Atorvastatin, 10 mg everynight, had been added 7 months before the current hospitaliza-tion. (The patient and the local Committee on Human Researchapproved publication of this report.)