Differentiated Thyroid Cancer in Children and Adolescents: Clinicopathological Characteristics of 32 Patients Followed up in our Pediatric Endocrinology Unit.

Objectives: This study aims to investigate the clinical and pathological features of patients with differentiated thyroid cancer (DTC) treated at our tertiary care institution. Methods: Thirty-two children and adolescents followed up with the diagnosis of DTC between 2001 and 2017 were enrolled. We classified patients with DTC into two groups as below and above 10 years of age, and compared their clinical and pathological features. Results: The mean age at presentation was 11.2±4 years. The female/male ratio was 7 (28:4). The diagnosis was papillary thyroid cancer (PTC) in 90.6% (n=29). The frequencies of lymph node and pulmonary metastases were 53.1% and 21.8%, respectively. The groups were comparable in terms of gender, initial clinical signs and tumor histopathology. The mean tumor size was greater in the younger age group (p=0.008). However, there was no difference between the two groups in terms of lymph node and pulmonary metastases. The pathological parameters associated with tumor aggressiveness were also similar between the groups, except lymphovascular invasion. Lymphovascular invasion was more frequent in the younger age group (p=0.01). Patients with lymph node and pulmonary metastases were more likely to have extrathyroidal extension and lymphovascular invasion. Conclusion: PTC was the most common type of DTC and presented with considerable rates of lymph node and pulmonary metastases. Tumor size was greater and lymphovascular invasion was more common in younger patients. Overall prognosis was favorable despite high rates of lymph node and pulmonary metastases.

Clinical indicators that influence a clinician's decision to start L-thyroxine treatment in prematurity with transient hypothyroxinemia.

BACKGROUND: Transient hypothyroxinemia of prematurity (THOP) is defined as a low level of circulating thyroxine (T4), despite low or normal thyroid-stimulating hormone (TSH) levels. AIMS: We aimed to evaluate the incidence of THOP, the clinical and laboratory findings of preterm infants with this condition and the levothyroxine (L-T4) treatment. METHODS: Preterm infants (n = 181) delivered at 24-34 weeks of gestation were evaluated by their thyroid function tests that were performed between the 10th and 20th days of postnatal life and interpreted according to the gestational age (GA) references. Clinical and laboratory characteristics of the patients with THOP and normal thyroid function tests were compared. Patients with THOP and treated with L-T4 were compared with the ones who were not regarding laboratory, and clinical characteristics. RESULTS: Incidence of hypothyroxinemia of prematurity was 45.8% (n = 83). Euthyroidism, primary hypothyroidism, and subclinical hypothyroidism were diagnosed in 47.5% (n = 86), 5% (n = 9) and 1.7% (n = 3) of the patients, respectively. Mean birth weight (BW) and GA were significantly lower in the hypothyroxinemia group than in the euthyroid group (p < 0.001). L-T4 was started in 43% (n = 36) of the patients with THOP. Treatment initiation rate was 44.4% (n = 16) in 24-27 wk, 41.6% (n = 15) in 28-30 wk, and 13.8% (n = 5) in 31-34 wk. As the GA increased, the incidence of THOP and the rate of treatment initiation decreased (p < 0.001). The lowest free thyroxine (FT4) cut-off value was 0.72 ng/dl in the treated group. In addition, incidences of vancomycin + amikacin, caffeine, dopamine treatments, RDS, IVH, BPD, central catheter, FFP transfusion, and ventilator support were higher in the treated group (P < 0.05). CONCLUSION: This study revealed that prevalence of THOP increased as the GA and BW decreased. As the GA decreased, THOP patients requiring L-T4 treatment increased. Additionally, association with comorbid diseases increased the requirement of treatment.

Comparative analyses of surrogates of metabolic syndrome in children and adolescents with metabolically healthy obesity vs. metabolically unhealthy obesity according to Damanhoury's criteria.

OBJECTIVES: Metabolically healthy obesity (MHO) has been reported with varying frequencies in children. The reasons of metabolically healthy phenotype in some obese subjects are unclear. Our aim was to identify the frequency of MHO in obese subjects, to assess the potential associations of demographic characteristics, serum uric acid, alanine transaminase (ALT), pediatric nonalcoholic fatty liver disease fibsosis score probability (PNFS p) with MHO status and to evaluate the differences between MHO and metabolically unhealthy obesity (MUO) with regard to metabolic syndrome surrogates. METHODS: 251 consecutive obese subjects (125 females) aged 7-18 years were included. Subjects were classified as having MHO according to Damanhoury's criteria. Several metabolic variables were measured, PNFS p was calculated by using the formula: z=1.1+(0.34*sqrt(ALT))+ (0.002*ALP)-(1.1*log(platelets)-(0.02*GGT). RESULTS: Median age of the subjects was 12.5 yr (range: 7.0-17.0 yr). The frequency of MHO was 41 %. Subjects with MHO were significantly younger, had lower waist circumference (WC) and waist height ratio (WHtR) and lower HOMA-IR than those without MHO(p<0.05 for all). Frequencies of hyperuricemia, hypertransaminasemia, hepatosteatosis and PNFS p values≥8 were similar betwen the groups. When putatively influential factors associated with MHO status were assessed with logistic regression analysis, only WC(ß=1.03) and HOMA-IR(ß=1.166) emerged as significant factors(Nagelkerke R2=0.142). None of the investigated demographic factors were associated with MHO status. CONCLUSIONS: We found a remarkably high frequency of MHO status. Nevertheless, the absence of decreased frequencies of hyperuricemia, hypertransaminasemia and PNFS in subjects with MHO may suggest the need to reconsider the validity of the criteria defining MHO.

The association of metabolic syndrome status with sensorineural hearing loss in pediatric obese patients.

OBJECTIVES: The prevalences of pediatric obesity and its associated comorbidities such as metabolic syndrome (metS) are rising. The aim of this study was to evaluate the association of metS status with sensorineural hearing loss in pediatric obese patients. METHODS: A two-center observationalprospective study was designed. In this study, 252 consecutive treatment-naive pediatric obese patients aged 5.8-17.8 yr in a tertiary pediatric Endocrinology outpatient clinic were prospectively enrolled. Following standard clinical and biochemical evaluations, the obese patients were diagnosed as having metabolic syndrome (metS) or not according to Internetional Diabetes Federation Criteria. All the patients were evaluated with tympanometry and pure tone audiometry tests after otomicroscopic examination. Comparative analyses of audiometric evaluations were performed between metS+ and metS- subgroups of the obese patients. RESULTS: The median age of the patients was 12.5 yr (range: 6.0-17.8 yr) and 56.3% of the patients were male. Metabolic syndrome was diagnosed in 82 (32.5%) patients. Age, gender distribution, history of the ventilation tube, and pubertal stage of the metS + patients and metS- counterparts were not statistically different (p > 0.05 for all). Pure tone hearing thresholds at all frequencies (125, 250, 500, 1k, 2k, 4k, 8k) were significantly higher in the metS + group then the metS- group (p˂0.05 for all). The tympanometry results were not statistically different between the two groups (p˃0.05). Abdominal obesity, hypertension, fasting hyperglycemia and dyslipidemia were not associated with increased hearing thresholds in metS + patients (p˃0.05 for all). CONCLUSION: Metabolic syndrome was associated with increased rates of subclinical hearing loss in our cohort. None of the investigated metS components emerged as a positive association with hearing loss in our cohort. Longitudinal follow-up of our cohort may help probe the causality of the association we found.

Loss-of-function variants in SEMA3F and PLXNA3 encoding semaphorin-3F and its receptor plexin-A3 respectively cause idiopathic hypogonadotropic hypogonadism.

PURPOSE: Idiopathic hypogonadotropic hypogonadism (IHH) is characterized by absent puberty and subsequent infertility due to gonadotropin-releasing hormone (GnRH) deficiency. IHH can be accompanied by normal or compromised olfaction (Kallmann syndrome). Several semaphorins are known potent modulators of GnRH, olfactory, and vomeronasal system development. In this study, we investigated the role of Semaphorin-3F signaling in the etiology of IHH. METHODS: We screened 216 IHH patients by exome sequencing. We transiently transfected HEK293T cells with plasmids encoding wild type (WT) or corresponding variants to investigate the functional consequences. We performed fluorescent IHC to assess SEMA3F and PLXNA3 expression both in the nasal region and at the nasal/forebrain junction during the early human fetal development. RESULTS: We identified ten rare missense variants in SEMA3F and PLXNA3 in 15 patients from 11 independent families. Most of these variants were predicted to be deleterious by functional assays. SEMA3F and PLXNA3 are both expressed along the olfactory nerve and intracranial projection of the vomeronasal nerve/terminal nerve. PLXNA1-A3 are expressed in the early migratory GnRH neurons. CONCLUSION: SEMA3F signaling through PLXNA1-A3 is involved in the guidance of GnRH neurons and of olfactory and vomeronasal nerve fibers in humans. Overall, our findings suggest that Semaphorin-3F signaling insufficiency contributes to the pathogenesis of IHH.

Evaluation of the thyroid disorders in children with familial Mediterranean fever.

Although it is well-known that autoimmune thyroid diseases are more common in most of the autoimmune connective tissue diseases, the relationship between autoinflammatory diseases and autoimmune thyroid diseases has not well-evaluated yet and still remains unclear. The aim of this study was to investigate the frequency of autoimmune diseases of the thyroid gland and to evaluate thyroid function tests in children with familial Mediterranean fever. Thyroxine, thyroid-stimulating hormone, and thyroid autoimmune markers such as thyroid peroxidase and thyroglobulin antibodies, and thyroid ultrasound findings of 133 patients with familial Mediterranean fever and 70 healthy controls were evaluated. Serum levels of thyroid-stimulating hormone, free thyroxine, and thyroid autoimmunity markers were similar in patients with familial Mediterranean fever compared with healthy controls. There was no relationship between the duration of the disease and thyroid-stimulating hormone, free thyroxine, anti-thyroid peroxidase, and anti-thyroglobulin levels. This study revealed that incidence of thyroid dysfunction and autoimmunity is not increased in patients with familial Mediterranean fever. In conclusion, routine screening of serum thyroid function tests and thyroid antibody levels is not required in patients with familial Mediterranean fever in the absence of clinical symptoms or family history. Key Points • It is well-known that autoimmune thyroid diseases are common in autoimmune diseases. • The relationship between autoimmune thyroid diseases and autoinflammatory diseases like familial Mediterranean fever is still unclear. • In this study, we report the similar frequency of the autoinflammatory thyroid diseases in patients with familial Mediterranean fever and healthy controls. • A routine screening of serum thyroid function tests and thyroid antibody levels may not be required in patients with familial Mediterranean fever in the absence of clinical symptoms or family history.