Introduction: Goiter is one of the most common thyroid disorders, yet its etiology is still not completely understood. Previous studies suggested a possible genetic predisposition in combination of environmental factors. The importance of an ethnic hereditary factor in goiter prevalence has rarely been studied. Israel has a diverse ethnic composition: Jews, Muslim and Druze. A previous study of the Israeli Druze has demonstrated that they are genetically a population isolate. The prevalence of goiter in the Israeli Druze has yet to be studied. Objectives: The purpose of this study is to examine goiter prevalence in the Druze population of northern Israel compared with Jewish and Muslim populations in the same region. Methods: A retrospective study of adult patients presented with goiter to the head and neck clinic in Ziv medical center between 2019-2021. Only patients from the same geographical area were included in the analysis. Patient files were reviewed for their demographic data and other goiter related clinical characteristics. Results: A total of 392 patients were included in the study. Of the reviewed files 235 were Jewish, 123 Druze and 34 Muslims. The overall incidence of goiter in the Druze group was 6.92% (CI 5.75-8.25) compared to 4.11% in the Jewish (CI 3.60-4.67) group and 7.21% (CI 4.99-10.08) in the Muslim group. Conclusions: Goiter prevalence in the Druze population is higher compared to the Jewish population in northern Israel. Further studies of possible genetic factors are warranted. A larger study of goiter in the Israeli Muslims is also warranted.

Background: DICER1, cancer predisposition syndrome (CPS), seems to escape timely diagnosis in pediatric patients. Case report 1: A 16-year-old female patient was referred to the endocrinology ward due to a large goiter. Her medical history indicated normal sexual maturation, with menarche occurring at 13.5 years. Over the past 2.5 years, she developed pronounced androgenic symptoms, including a deepened male voice, facial, back and neckline acne, hirsutism, and menstrual irregularities leading to secondary amenorrhoea. A thyroid ultrasound identified a multinodular goiter with cystic-solid lesions containing calcifi-cations. An abdominal ultrasound identified a 5.7x6.9 cm solid mass in the right adnexal region, displacing the uterus to the left. Histopathological examination confirmed a Sertoli-Leydig cell tumor. The patient was subjected to total thyroidectomy. Histopathology revealed benign follicular cell-derived neoplasms. Thyroid follicular nodular disease was diagnosed bilaterally. DNA analysis using NGS, confirmed by the Sanger method, revealed a pathogenic heterozygotic variant c.2953>T [p.Gln985*] in exon 18 of DICER1 gene. Case report 2: A 12-year-old male patient was admitted to the pediatric surgery unit due to a 33 ml goiter. A month prior to admission, the patient discovered a palpable nodule in his neck, accompanied by hoarseness. An ultrasound revealed a multinodular goiter. Molecular analysis revealed a pathogenic heterozygotic variant c.2782C>T [p.Gln928Ter] in exon 17 of DICER1 gene. Subsequently, a total thyroidectomy was performed, and histopathological examination revealed thyroid follicular nodu-lar disease bilaterally. Conclusion: Multinodular goiter, although rare in pediatric population, when accompanied by characteristic ultrasound and histopathological features, and by additional features such as androgen excess, warrants exclusion of DICER1 syndrome.

Obstructive sleep apnea (OSA) may be linked to various factors that narrow the upper airways, such as obesity, adenotonsillar hypertrophy and craniofacial abnormalities. Hypothyroidism has also been described as a risk factor for OSA. However, the implication of goiter independently of thyroid function in the occurrence of OSA remains unclear. We present the case of a 66-year-old patient, with a large compressive multinodular goiter for whom total thyroidectomy was indicated. During the preoperative assessment, the patient showed a body mass index (BMI) of 37.8 kg/m2 with symptoms of OSA. Respiratory polygraphy confirmed the diagnosis of severe OSA (apnea hypopnea index: AHI=32) and treatment with continuous positive airway pressure (CPAP) was initiated prior to thyroid surgery. Surprisingly, after total thyroidectomy, OSA symptoms disappeared and the patient abandoned CPAP therapy. Subsequent respiratory polygraphy after thyroidectomy showed a decrease in AHI to a normal value (AHI < 5). Interestingly, there was no change in BMI or other factors explaining the resolution of OSA, except for thyroidectomy. This case report suggests that goiter can be considered a risk factor for OSA. However, prospective studies are needed to accurately assess the effects of goiter on occurrence of OSA according to its dimensions and local extension.

Iodide is an essential micronutrient present in very small quantities in the human body, with a fundamental action for the adequate synthesis of thyroid hormones, which are critical for cell differentiation, growth and metabolism. In the form of iodide, iodine is widely distributed in the environment, although in an irregular manner, occurring in abundant amounts in the oceans and in coastal areas and scarcely found on islands and mountains. The diet is the main source of iodine, whose intake varies according to the amount present in soil and water and according to eating habits. Governmental policies have been adopted to satisfy and guarantee the necessary daily supply of iodine, such as fortification of industrialized salt for domestic iodine consumption or addition to the bread commonly consumed in a given region, or the offer of iodized oil to the population, or even iodine supplementation through medications. Iodide deficiency is the main avoidable cause of brain damage to fetuses and children, as well as retardation of psychomotor development. Thyroid hormones are almost universally involved in the development and proliferation of fetal neural tissue. Permanent lesions of the cerebral cortex, hippocampus and cerebellum may occur, with loss of, or damage to the brainstem or spinal cord, affecting cortical areas that integrate highly specialized stimuli, which become poorly defined on an anatomical basis, including silent areas of the associative cortex. One of the more significant metabolic problems due to dietary iodine deficiency is the presence of goiter (increased volume of the thyroid gland). Thyroid carcinoma is the most frequent endocrine neoplasia affecting the human species and plasma iodine concentration is related to the development of specific subtypes of this neoplasia. An increased prevalence of follicular carcinoma, a more aggressive tumor, has been observed in areas of iodine deficiency, while the correction of this deficiency is associated with a higher prevalence of papilliferous carcinoma, a less aggressive form. CONCLUSION: An ideal plasma iodide concentration is necessary to insure the proper mental development of fetuses and young children and to minimize the aggressiveness of thyroid cancer from follicular cells in humans.

It has been reported that prostaglandin I2, such as epoprostenol, develops Grave's disease. A 34-year-old woman was diagnosed with idiopathic pulmonary arterial hypertension and started receiving continuous intravenous epoprostenol. Three years after starting epoprostenol, she started complaining of neck swelling and was diagnosed with Grave’s disease. Thyroid function was controlled by thiamazole and levothyroxine. Nevertheless, her thyroid gland enlargement worsened as epoprostenol dose was titrated. After 23 years of treatment with epoprostenol, she suddenly experienced respiratory failure with a giant goiter leading to airway stenosis and passed away. The autopsy confirmed a giant goiter associated with hyperthyroidism and airway stenosis. We experienced a case of idiopathic pulmonary hypertension with a giant goiter and airway stenosis after long-term intravenous epoprostenol therapy.