Gurbuz Erdogan

Iodine status and goiter prevalence in Turkey before mandatory iodization

Endemic goiter is an important public health problem in Turkey. Legislation for mandatory iodization of household salt was passed in July 1999. Current study is aimed at ascertaining the goiter prevalence and iodine nutrition in school-age children (SAC) living in known endemic areas of Turkey. Sonographic thyroid volumes (STV) and urinary iodine concentrations (UIC) of 5,948 SAC from 20 cities were measured between 1997–1999. STV of 31.8% of the SAC examined stayed above the upper-normal limits for the same age and gender recommended by the World Health Organization (WHO). Goiter prevalence ranged between 5 to 56% and median UIC ranged between 14 to 78 μg/l, indicating severe to moderate iodine deficiency (ID) in 14 and mild ID in 6 of the cities surveyed. Neither of the cities was found to have sufficient median UIC levels. The current study shows that endemic goiter is an important public health problem and iodine nutrition is inadequate nationwide. It also provides reliable scientific evidence and shows the need for a controlled and effective iodine supplementation program nationwide. Mandatory iodization of household salt seems to be the essential measure taken for the moment, additional measures may be needed in the near future.

Comparative effects of atorvastatin and simvastatin on the plasma total homocysteine levels in women with polycystic ovary syndrome: a prospective randomized study.

OBJECTIVE To test the hypothesis that statins improve hyperhomocysteinemia in women with polycystic ovary syndrome (PCOS). DESIGN A prospective randomized study. SETTING University Hospital. PATIENT(S) Fifty-two women with PCOS and 52 women matched for age and body mass index as controls. INTERVENTION(S) Patients were randomly divided into two groups for treatment: group 1, atorvastatin, 20 mg daily (n = 26), and group 2, simvastatin, 20 mg daily (n = 26). Blood samples were obtained before and after treatment. MAIN OUTCOME MEASURE(S) Serum homocysteine levels. RESULT(S) After 12 weeks of treatment, serum homocysteine levels in group 1 had decreased from 14.3 +/- 2.9 to 10.6 +/- 1.7 micromol/L; in group 2, the levels decreased from 13.6 +/- 2.1 to 11.1 +/- 1.9 micromol/L. Both two groups, free testosterone and total testosterone declined statistically significantly (38.3% and 36.5%; and 40.6% and 46.0%, respectively). In group 1, vitamin B(12) increased from 362.1 +/- 107 to 478.7 +/- 267 pg/mL; in group 2, it increased from 391.3 +/- 107 to 466 +/- 211 pg/mL, but the change did not reach statistical significance. There was a considerable decline in the homeostatic model assessment index in group 1 (40.0% to 32.1%). CONCLUSION(S) Treatment with statins in women with PCOS leads to decreases in serum homocysteine levels.

Is it useful to routinely biopsy hot nodules in iodine deficient areas

Incidence of nodular thyroid disease as well as that of functioning thyroid nodules (FTN) increases dramatically in iodine deficient (ID) areas. Cancer is extremely rare in FTN; thus, some do not routinely biopsy and treat them with radioactive iodine (RAI) straight away or follow-up. The outcome of 296 patients followed or treated at our institution for solitary or multiple FTN were retrospectively evaluated. Hospital records of 224 female, 72 male patients, with a mean ±SD age of 54.9±12.4 yr and followed for 22 (0–156) months were examined. 175 patients had solitary, 121 had multiple hot or warm nodules. 230 (77.7%) of the patients received RAI treatment. 402 fine needle aspiration biopsies (FNABs) were performed on 260 patients and on 343 FTN (381 benign and 21 suspicious diagnoses). Eleven of the patients were operated for suspicious FNAB results and 10 were followed-up. Only one nodule turned out to be malignant. Malignancy is extremely rare in functioning thyroid nodules (0.34%) and some of malignant cases could be predicted by their suspicious clinical features. Routine practice of treating FTN with RAI therapy is reasonable in clinically low-risk patients. FNAB is reserved for cases with suspicious clinical features, resulting in fewer surgeries and reduced cost.

Natural course of benign thyroid nodules in a moderately iodine‐deficient area

Objective  Few studies using ultrasonographic evaluation have addressed the natural course of benign thyroid nodules. In this study, we present the long‐term analysis of benign, untreated thyroid nodules in a moderately iodine‐deficient area.

More Than a Decade of Iodine Prophylaxis Is Needed to Eradicate Goiter Among School Age Children in a Moderately Iodine-Deficient Region

BACKGROUND There are many studies regarding the effect of iodine supplementation on goiter, but relatively few reports on the duration of iodine supplementation required to eradicate goiter in iodine-deficient regions. In the current study, we aimed to determine goiter prevalence as determined by sonographic methods, as it relates to changes in median urinary iodine concentrations (UIC) among school age children (SAC), ages 9-11. METHODS This study was performed in Ankara, Turkey, before and 5-10 years after mandatory iodination of table salt. Three hundred to 400 SAC from the same primary schools were studied every year by measurement of UIC as part of Turkish Iodine Surveys. Sonographically determined thyroid volume of the SAC had been measured before the mandatory iodination in 1997 and 5-10 years afterward, in 2002 and 2007. The prevalence of goiter in children was evaluated using World Health Organization/International Council for the Control of Iodine Deficiency Disorders recommendations for age and sex. RESULTS Moderate iodine deficiency was present in 1997 (median UIC, 25.5 microg/L), and it improved to mild iodine deficiency in 2001 (median UIC, 87 microg/L). Sufficient iodine intake (median UIC, 117 microg/L) was achieved by the year 2004. Goiter prevalence was 25% in 1997, 12.3% in 2001, and decreased to 1.3% in 2004. CONCLUSION The time required to normalize the prevalence of goiter in SAC living in a moderately iodine-deficient environment was at least a decade. To achieve a goiter rate of less than 5% among SAC, it may require that, as a population, they were born and grew up under conditions of iodine sufficiency.

A Stepwise Approach to the Treatment of Amiodarone-Induced Thyrotoxicosis

Amiodarone-induced thyrotoxicosis (AIT) is a complex therapeutic challenge. Two major forms have been described: type I and type II. Methimazole (MMI) and potassium perchlorate (KCLO(4)) is the treatment of choice for the former, whereas corticosteroids are used for the latter. However, mixed forms appear frequently and it is not easy to prescribe corticosteroids because of side effects. The present study investigated the validity of a stepwise therapeutic approach to AIT. Twenty patients with AIT were given 30-50 mg/d of MMI and 1000 mg/d of KCLO(4) initially for a month. Euthyroidism or a significant decrease in serum thyroid hormone levels could be achieved in 12 of the patients (7 with type I, 5 type II). Prednisolone, 40-48 mg/d was added for the 8 nonresponding patients (7 type I, 1 type II) and euthyroidism was achieved in all. The prednisolone dose was decreased when free thyroxine (T(4)) levels normalized, and MMI was titrated, maintaining euthyroidism until urinary iodine excretion normalized. Mixed forms of AIT may prevail in iodine-deficient areas. Initial classification of the patients may cause unnecessary corticosteroid use in a substantial number of patients with AIT. A stepwise approach is feasible; however, when the patient is gravely ill, MMI, KCLO(4), and prednisolone could be prescribed simultaneously.

Endemic goiter, thiocyanate overload, and selenium status in school-age children.

Iodine deficiency (ID) and related disorders are still major, yet unresolved health concerns. Recently, in a systematic survey of schoolage children (SAC), we reported severe to moderate ID, in Ankara and three cities from Black Sea region of Turkey. The current study attempted to evaluate selenium (Se) status, thiocyanate (SCN−) overload, and their possible contribution to the goiter endemics and thyroid hormone profile observed in these cities. Thyroid ultrasonography was performed and serum Se, SCN−, thyroid hormones, sensitive TSH (sTSH) levels, and urinary iodine concentrations (UICs) were determined from 251 SAC (9–11 yr old).Thyroid volumes (TVs) exceeding recommended upper normal limits and median UIC indicated goitre endemics and moderate to severe ID in the areas studied. Mean serum SCN− concentrations were found to be greater than the controls from the literature. The UIC/SCN− ratio was found to be lowest in Bayburt and Trabzon denoting that SCN− overload may contribute to the goiter endemics. Serum Se concentrations represent a marginal deficiency in the four areas studied. No significant correlations between serum Se concentrations and the other parameters studied (i.e., TV, SCN−, thyroid hormones, sTSH, UIC) was detected.In conclusion, this study showed that selenium is also marginally deficient in the iodine-deficient endemic areas studied, but this has little or no impact on the thyroid hormone profile and the goiter endemics. SCN− overload may contribute to the endemics, especially for the areas where iodine is severely deficient. An effective iodine supplementation program will not only resolve the goiter endemics but also the consequence of SCN− overload as well in the endemic goiter areas studied.

25-Hydroxy vitamin D levels and endothelial vasodilator function in normotensive women

Introduction Vitamin D was shown to be related to endothelial function and blood pressure. Reactive hyperaemia index (RHI) measurement by pulse arterial tonometry is a new method to evaluate vasodilator function of endothelium. We aimed to evaluate the relationship between vitamin D levels and RHI in women. Material and methods We enrolled 56 normotensive, nonsmoker, normolipidemic and normoglycemic women, (23 with 25-OH-vitamin D levels>20 µg/l, and 33 with values lower than 20 µg/l). The cardiologist who was blind for vitamin D results executed measurements by pulse arterial tonometry. The measurement was performed on the lying patient with pre- and post-occlusion measurements of RHI by digital sensors placed on each index finger, by 5 min intervals. Pulse amplitudes were recorded, pre-occlusion and post-occlusion ratio was compared by the software of device. Stepwise linear regression and multiple regression analyses were performed to evaluate predictors of endothelial function. Results The low vitamin D group had a lower RHI value than the normal vitamin D group (p = 0.042). In regression analysis, positive predictors of RHI were serum 25-OHD (β = 0.401; 95% CI 0.010–0.042, p = 0.002), serum albumin (β = 0.315; 95% CI 0.286–2.350, p = 0.013), and, inversely, serum calcium (β = −0.247; 95% CI (−1.347)-(−0.010), p = 0.047). Conclusions Serum 25-hydroxy vitamin D was significantly related to endothelial functions measured as RHI, even in healthy non-smoker women.

Significance of the RET proto-oncogene polymorphisms in Turkish sporadic medullary thyroid carcinoma patients

Several single nucleotide polymorphisms (SNP) of the RET gene have been identified in medullary thyroid carcinoma (MTC) patients as well as in the general population. However, the relevance of SNP for MTC patients is still controversial, whether these allelic variants play other interacting, predisposing or modifying roles in clinical behavior of MTC. The aim of this work is to elaborate allelic frequencies of the RET proto-oncogene polymorphisms in Turkish sporadic MTC patients and to demonstrate if there is an association between SNP and the clinical disease features, specifically the age at onset of MTC and lymph node involvement at diagnosis. We analyzed the allelic frequencies of SNP of the exon 11, 13, 14 and 15 of the RET proto-oncogene in blood samples from 50 sporadic MTC patients, using the polymerase chain reaction methodology followed by DNA sequencing. The observed allelic frequencies were 24% for G691S polymorphism in exon 11, 29% for L769L polymorphism in exon 13, 5% for S836S polymorphism in exon 14, and 26% for S904S polymorphism in exon 15. These frequencies are similar to those reported in other countries. We did not observe any significant association of all four SNP with the age at onset of MTC. Our results indicate a possible association between the presence of lymph node involvement at the time of diagnosis (extent of disease) and L769L or S836S polymorphism. However, it is not possible to draw definitive conclusions that these two polymorphisms play a significant role in clinical behavior of MTC. Further studies are needed to evaluate the role of this polymorphism in the clinical behavior of MTC.

Multiple endocrine neoplasia type 2A/localized cutaneous lichen amyloidosis associated with malignant pheochromocytoma and ganglioneuroma

We hereby present a rare variant of multiple endocrine neoplasia type 2A (MEN2A) associated with a rare skin disease primary cutaneous lichen amyloidosis and discrete malignant pheochromocytoma in both adrenal glands and pancreatic tail, and interestingly accompanied ganglioneuroma located in retroperitoneum in a 34-yr-old female. The presence of composite tumor of pheochromocytoma and ganglioneuroma arising in the adrenal glands has been described previously in MEN2A and in sporadic cases. The patient displayed classical signs and symptoms of catecholamine excess. Biochemical screening proved pheochromocytoma. Computed tomography revealed multiple mass lesions in both adrenal glands. It also showed a large heterogeneous mass that clearly discriminated from right adrenal gland in retroperitoneal location. After surgical exploration, both adrenal glands and the suspicious mass in pancreatic tail were removed successfully together with subtotal resection of the retroperitoneal tumor. Histopathologic examinations confirmed the presence of pheochromocytoma in both adrenal glands as well as pancreatic lesion. A retroperitoneal ganglioneuroma was also present. Symptomatic and biochemical evidence of pheochromocytoma subsided after the operation. Further evaluation for medullary thyroid carcinoma and primary hyperparathy-roidism confirmed MEN2A. Mutation analysis of the ret proto-oncogene revealed a missense point mutation at position 634 in exon 11, which gives rise to the substitution of a cysteine codon with a tyrosine residue.