Distribution of RET mutations and evaluation of treatment approaches in hereditary medullary thyroid carcinoma in Turkey

Objective: This retrospective multicenter study, centrally conducted and supported by the Society of Endocrinology and Metabolism of Turkey, aimed to evaluate the impact of free RET proto-oncogene testing in medullary thyroid carcinoma (MTC) patients. Surgical timing, adequacy of the treatment, and frequency of prophylactic thyroidectomy (PTx) in mutation carriers were also assessed. Methods: Genetic testing for MTC and pheochromocytoma was conducted between July 2008 and January 2012 in 512 patients. Application forms and RET mutation analyses of these patients whose blood samples were sent from various centers around Turkey were assessed retrospectively. An evaluation form was sent to the physicians of the eligible 319 patients who had confirmed sporadic MTC, familial MTC (FMTC), multiple endocrine neoplasia type 2 (MEN2), or who were mutation carriers. Physicians were asked to give information about the surgical history, latest calcitonin levels, morbidity, mortality, genetic screening, and PTx among family members. Twenty-five centers responded by filling in the forms of 192 patients. Results: Among the 319 patients, RET mutation was detected in 71 (22.3%). Cys634Arg mutation was the most prevalent mutation (43.7%), followed by Val804Met in 18 patients (25.4%), and Cys634Tyr in 6 patients (8.5%). Among 192 MTC patients, the diagnosis was sporadic MTC in 146 (76.4%), FMTC in 14 (7.3%), MEN2A in 15 patients (7.9%), and MEN2B in one patient. The number of mutation carriers among 154 apparently sporadic MTC patients was 8 (5.2%). Ten patients were submitted to PTx out of twenty-four mutation carriers at a mean age of 35 +/- 19 years. Conclusion: Turkish people have a similar RET proto-oncogene mutation distribution when compared to other Mediterranean countries. Despite free RET gene testing, the number of the PTx in Turkey is limited and relatively late in the life span of the carriers. This is mainly due to patient and family incompliance and incomplete family counselling.SEM

Should neck pain in a patient with Hashimoto's thyroiditis be underestimated? A case and review of the literature

Hashimoto's Thyroiditis (HT) is an autoimmune disease and the most frequent cause of hypothyroidism. Subacute thyroiditis (SAT) overlapping HT is a rare entity. A 69-year-old female patient with HT and multinodular goiter has been followed on levothyroxine replacement therapy for 7 years. She presented with neck pain radiating to the right ear persisting for 2 months. She was prescribed analgesics and antibiotics by other physicians during that period, which did not work. Her vital signs were stable with no tachycardia or fever. The right lobe of the thyroid gland was tender on palpation. Her TSH level was 3.94 mIU/ml, ESR 23 mm/h, CRP 3.2 mg/l, WBC 4900/μl at presentation. Thyroid ultrasonography revealed a hypoechoic area over the tender lobe. Power Doppler imaging revealed almost no blood flow in that area. She was started on methylprednisolone 32 mg/day. At day 10 of therapy, her symptoms had completely resolved. Ultrasonography repeated showed that the hypoechoic area had disappeared. Glucocorticoid dosage was tapered and stopped. Emergence of subacute thyroiditis in a case with preexisting Hashimoto's thyroiditis is a quite rare condition, but should be kept in mind along with a painful attack of HT in the differential diagnosis

Metformin Decreases Thyroid Volume and Nodule Size in Subjects with Insulin Resistance: A Preliminary Study

Objective: The aim of this study was to investigate the effects of metformin on thyroid volume and nodule size. Subjects and Methods: Prospective data were gathered on 100 newly diagnosed subjects with insulin resistance (68 female, 32 male) between August 2008 and May 2010. Each subject followed a standard diet and exercise program, and received 1,700 mg/day of metformin therapy for 6 months. The height, weight, waist circumference (WC) and thyroid hormone levels of each subject were measured. Additionally, the dimensions of the thyroid lobes and maximum diameter of each thyroid nodule were determined by ultrasonography. BMI and thyroid volumes were also calculated. Insulin resistance was estimated by homeostasis model assessment. All these parameters were measured at the beginning and at the end of the treatment period. Results: BMI and WC decreased significantly after metformin therapy (34.5 +/- 5.1 vs. 32.7 +/- 4.8, p < 0.0001, and 106.3 +/- 11.8 vs. 101.8 +/- 19.0 cm, p = 0.008, respectively). Insulin resistance also decreased after metformin therapy (4.5 +/- 1.9 vs. 2.9 +/- 1.7, p < 0.0001). The mean thyroid volume (22.5 +/- 11.2 vs. 20.3 +/- 10.4 ml, p < 0.0001) and mean thyroid nodule size (12.9 +/- 7.6 vs. 11.7 +/- 7.2 mm, p < 0.0001) also decreased after treatment. Conclusion: In subjects with insulin resistance, metformin therapy significantly decreased thyroid volume and nodule size. (C) 2015 S. Karger AG, Base

Thyroid volume in patients with glucose metabolism disorders

Objective: Thyroid volume and the prevalence of thyroid nodules are higher in patients with insulin resistance. A relationship between thyroid volume and glucose metabolism disorders (GMD) has not as yet been clarified. The present retrospective study aimed to investigate the association between GMD and thyroid volume. Subjects and methods: We investigated the data of 2,630 patients who were evaluated for thyroid biopsy in our hospital. The study population included 602 patients with GMD, 554 patients with diabetes mellitus (DM) and 1,474 patients with normal glucose metabolism as a control group. We obtained the levels of serum thyroid stimulating hormone (TSH) and the thyroid volumes of those patients retrospectively. Results: The median ages for the control group, GMD group and DM group were 55 (15-91) years, 60 (27-97) years, and 65 (27-91) years respectively and there was a statistically significant difference between the groups with regard to age and gender (p < 0.001). Levels of TSH were similar in all groups. The median total thyroid volumes for patients with DM and GMD were significantly higher than that of the control group [22.5 (3-202) mL, 20.2 (4-190) mL, and 19.2 (3-168) mL respectively, p <= 0.001 for all parameters]. Also the median total thyroid volume for patients with DM was significantly higher than that of the GMD group (p < 0.001). According to the correlation analysis, thyroid volume was significantly correlated with age (r = 0.92, p < 0.001) and TSH (r = 0.435, p < 0.001). Age, gender, TSH levels, GMD and DM diagnosis were independently correlated with thyroid volume. Conclusion: The thyroid gland is one of the target tissues of metabolic disorders. We reported a positive correlation between GMD/type 2 DM and thyroid volume. Further controlled, prospective, randomized studies on this subject are required to gain more information

Thyroid Nodules Are More Prevalent in Subjects with Colon Polyps, Independent of Insulin Resistance

Objective: Colorectal polyps and thyroid nodules are common disorders linked to hyperinsulinemia and metabolic syndrome (Mets). The direct association between these two diseases is not clear. We aimed to analyze the prevalence of thyroid nodules in subjects with and without colorectal polyps. The secondary aim was to establish the prevalence of Mets and its parameters in both disorders and to determine if insulin resistance and hyperinsulinemia are common underlying pathophysiological mechanisms. Subjects and Methods: One hundred and five subjects with colorectal polyps (71 males, 34 females) and 68 controls (28 males, 40 females) were enrolled. The parameters of Mets together with TSH, insulin, low-density lipoprotein cholesterol, and homeostasis model for assessment of insulin resistance levels were calculated. We performed thyroid ultrasonography in all participants. Results: The prevalence of Mets was similar in the colorectal polyp and control groups (37.1 vs. 37.3%, p = 0.982). The prevalence of Mets was nonsignificantly higher in subjects with a documented thyroid nodule compared to subjects without a thyroid nodule (43.0 vs. 32.6%, p = 0.205). The prevalence of thyroid nodules in subjects with colorectal polyps was significantly higher than in subjects without polyps (52.9 vs. 35.3%, p = 0.017). Compared to subjects with no colorectal polyps, we established a significant increase in the odds of having thyroid nodules (OR 2.05; 95% CI: 1.097-3.860, p = 0.017). The presence of colorectal polyps and age in the adjusted model were established to be independent risk factors for having thyroid nodules (p = 0.025 and p = 0.007, respectively). Conclusion: These results may support the presence of other common mechanisms in the development of these two pathologies other than insulin resistance and hyperinsulinemia. (C) 2019 The Author(s) Published by S. Karger AG, Base

A comparison of glycemic effects of glimepiride, repaglinide, and insulin glargine in type 2 diabetes mellitus during Ramadan fasting

Although diabetics may be exempted from Ramadan fasting, many patients still insist on this worship. Aim of the present study is to compare the effects of glimepiride, repaglinide, and insulin glargine in type 2 diabetics during Ramadan fasting on the glucose metabolism. Patients, who were willing to fast, were treated with glimepiride (n = 21), repaglinide (n = 18), and insulin glargine (n = 10). Sixteen non-fasting control type 2 diabetics matched for age, sex, and body mass index were also included. Fasting blood glucose (FBG), post-prandial blood glucose (PBG), HbA1c, and fructosamine as well as lipid metabolism were evaluated in pre-Ramadan, post-Ramadan, and I-month post-Ramadan time points. There was no significant change from pre-Ramadan in FBG, PBG, and HbA1c variables in fasting diabetics at post-Ramadan and 1-month post-Ramadan. However, PBG was found higher in non-fasting control diabetics at post-Ramadan and 1-month post-Ramadan (p < 0.05 and p < 0.001, respectively). In fructosamine levels, a significant increase was noted both in fasting group and non-fasting group at 1-month post-Ramadan (p < 0.01 for all). However, no significant difference was found in the comparison of the changes in fructosamine levels between fasting group and non-fasting group. Risk of hypoglycemia did not significantly differ between fasting and non-fasting diabetics. There was no significant difference between three drug therapies regarding glucose metabolism and rate of hypoglycemia. No adverse effects on plasma lipids were noted in fasting diabetics. In this fasting sample of patients with type 2 diabetes, glimepiride, repaglinide, and insulin glargine did not produce significant changes in glucose and lipid parameters. (c) 2006 Elsevier Ireland Ltd. All rights reserved