Banu Kucukemre Aydin

Rare Causes of Primary Adrenal Insufficiency: Genetic and Clinical Characterization of a Large Nationwide Cohort

Context: Primary adrenal insufficiency (PAI) is a life-threatening condition that is often due to monogenic causes in children. Although congenital adrenal hyperplasia occurs commonly, several other important molecular causes have been reported, often with overlapping clinical and biochemical features. The relative prevalence of these conditions is not known, but making a specific diagnosis can have important implications for management. Objective: The objective of the study was to investigate the clinical and molecular genetic characteristics of a nationwide cohort of children with PAI of unknown etiology. Design: A structured questionnaire was used to evaluate clinical, biochemical, and imaging data. Genetic analysis was performed using Haloplex capture and next-generation sequencing. Patients with congenital adrenal hyperplasia, adrenoleukodystrophy, autoimmune adrenal insufficiency, or obvious syndromic PAI were excluded. Setting: The study was conducted in 19 tertiary pediatric endocrinology clinics. Patients: Ninety-five children (48 females, aged 0–18 y, eight familial) with PAI of unknown etiology participated in the study. Results: A genetic diagnosis was obtained in 77 patients (81%). The range of etiologies was as follows: MC2R (n = 25), NR0B1 (n = 12), STAR (n = 11), CYP11A1 (n = 9), MRAP (n = 9), NNT (n = 7), ABCD1 (n = 2), NR5A1 (n = 1), and AAAS (n = 1). Recurrent mutations occurred in several genes, such as c.560delT in MC2R, p.R451W in CYP11A1, and c.IVS3ds+1delG in MRAP. Several important clinical and molecular insights emerged. Conclusion: This is the largest nationwide study of the molecular genetics of childhood PAI undertaken. Achieving a molecular diagnosis in more than 80% of children has important translational impact for counseling families, presymptomatic diagnosis, personalized treatment (eg, mineralocorticoid replacement), predicting comorbidities (eg, neurological, puberty/fertility), and targeting clinical genetic testing in the future.

Thyroid dyshormonogenesis is mainly caused by TPO mutations in consanguineous community

In this study, we aimed to investigate the genetic background of thyroid dyshormonogenesis (TDH).

Adherence to Growth Hormone Therapy: Results of a Multicenter Study

OBJECTIVE To evaluate the adherence to growth hormone (GH) therapy and identify the influencing factors and outcomes in children. METHODS A total of 217 GH-naïve patients in 6 pediatric endocrinology clinics were enrolled in the study. Structured questionnaires were filled out and patients were evaluated at the initiation and 3rd, 6th, and 12th months of therapy. Patients were categorized into 4 adherence segments based on percentage of doses omitted at each evaluation period, classified as excellent if 0%, good if 5%, fair if 5 to 10%, and poor if > 10%. RESULTS There was a decrement in adherence to GH therapy during the study period (P = .006). Patients who showed excellent and good adherence to therapy had better growth velocity and growth velocity standard deviation scores (SDSs) (P = .014 and P = .015, respectively). A negative correlation between growth velocity SDS and number of missed injections was also observed (r = -.412; P = .007). A positive correlation between delta insulin-like growth factor-1 (IGF-1) SDS and growth velocity was demonstrated (r = .239; P = .042). IGF-1 levels were significantly higher in patients who showed excellent and good adherence to therapy (P = .01). Adherence was better in boys than in girls (P = .035), but adherence rates were not associated with age, cause of GH treatment, socioeconomic status, person who administered the injections, type of injection device, or GH product. CONCLUSION Poor adherence to GH therapy was common in our group of patients and was one of the factors underlying suboptimal growth during therapy. Before considering other problems that can affect growth, clinicians should confirm good adherence to therapy.

TSHR is the main causative locus in autosomal recessively inherited thyroid dysgenesis.

Abstract Congenital hypothyroidism (CH) is the most common neonatal endocrine disorder and results in mental retardation if untreated. Eighty-five percent of CH cases are due to disruptions in thyroid organogenesis and are mostly sporadic, but about 2% of thyroid dysgenesis is familial, indicating the involvement of genetic factors in the aetiology of the disease. In this study, we aimed to investigate the Mendelian (single-gene) causes of non-syndromic and non-goitrous congenital hypothyroidism (CHNG) in consanguineous or multicase families. Here we report the results of the second part (n=105) of our large cohort (n=244), representing the largest such cohort in the literature, and interpret the overall results of the whole cohort. Additionally, 50 sporadic cases with thyroid dysgenesis and 400 unaffected control subjects were included in the study. In familial cases, first, we performed potential linkage analysis of four known genes causing CHNG (TSHR, PAX8, TSHB, and NKX2-5) using microsatellite markers and then examined the presence of mutations in these genes by direct sequencing. In addition, in silico analyses of the predicted structural effects of TSHR mutations were performed and related to the mutation specific disease phenotype. We detected eight new TSHR mutations and a PAX8 mutation but no mutations in TSHB and NKX2-5. None of the biallelic TSHR mutations detected in familial cases were present in the cohort of 50 sporadic cases. Genotype/phenotype relationships were established between TSHR mutations and resulting clinical presentations. Here we conclude that TSHR mutations are the main detectable cause of autosomal recessively inherited thyroid dysgenesis. We also outline a new genetic testing strategy for the investigation of suspected autosomal recessive non-goitrous CH.

Thyroid Hormones in Children on Antiepileptic Therapy

ABSTRACT The aim of this study was to evaluate the thyroid function alterations in a group of epileptic children taking antiepileptic drugs (AEDs). Patients demographic data and the free throxine (fT4) and thyroid-stimulating hormone (TSH) levels at the beginning of the treatment and at the third, sixth and ninth months of AED treatment were recorded retrospectively. A total of 106 children, 59 males and 47 females, were enrolled in the study. Mean patient age was 3.7 years, ranging between 3 months and 14 years. In total, 54% of patients were on valproic acid (VPA), 16% phenobarbital (PB), 14% were on carbamazepine (CBZ), 6% were on oxcarbazepine (OXC), 5% were on levetiracetam, and 5% were on topiramate therapy. There were no significant differences in average fT4 values between the drug groups. But the mean fT4 levels of the patients on VPA therapy showed a clear decrease within the observation period. No significant difference in average TSH values between the groups was detected in the beginning and in the third and sixth month. However, in the ninth month, a significant increase in TSH values was found in the VPA group (p = 0.007). In the patients taking VPA, average TSH values rose progressively while staying within normal limits. During follow-up, thyroid dysfunction were found in 21 patients (19.6%). A statistically significant relationship was found between severe electroencephalography (EEG) findings and thyroid dysfunction (p = 0.041). It was concluded that epileptic children with severe EEG findings and using VPA could have thyroid dysfunction. These patients should be followed up closely by thyroid function tests during treatment.

The exon 3-deleted/full-length growth hormone receptor polymorphism and response to growth hormone therapy in growth hormone deficiency and Turner syndrome: a multicenter study.

Background/Aim: The exon 3-deleted/full-length (d3/fl) growth hormone (GH) receptor (GHR) polymorphism has been associated with responsiveness to GH therapy in some diagnostic groups. However, there are still controversies on this issue. To evaluate the effect of the GHR exon 3 polymorphism on growth after 1 and 2 years of GH therapy in Turkish patients with GH deficiency (GHD) and Turner’s syndrome (TS) and the distribution of GHR exon 3 isoforms. Materials and Methods: 218 patients with GHD (125 males/93 females) and 43 patients with TS were included in the study. The control group included 477 healthy adults aged from 18 to 57 years (54 females/423 males). Anthropometric parameters and insulin-like growth factor (IGF)-1 and IGF binding protein (IGFBP)-3 were evaluated annually. GHR isoforms were studied using simple multiplex PCR. Height and body mass index were expressed as standard deviation score (SDS). Results: There were no differences among TS, GHD and healthy adults regarding the distribution of GHR exon 3 isoforms (fl/fl, fl/d3 and d3/d3). There was a significant increase in height SDS in both diagnostic groups on GH therapy; however, there were neither differences in height SDS and Δheight velocity between fl/fl, fl/d3 and d3/d3 groups nor a correlation between the distribution of GHR exon 3 isoforms and change in IGF-1 SDS and IGFBP-3 SDS levels on GH therapy in either of the diagnostic groups. There was also no gender difference in GHR isoforms in healthy adults. Conclusion: The results suggest that responsiveness to GH therapy does not depend on the exon 3 GHR genotypes in GHD and TS patients.

Turner syndrome and associated problems in turkish children: A multicenter study

Objective: Turner syndrome (TS) is a chromosomal disorder caused by complete or partial X chromosome monosomy that manifests various clinical features depending on the karyotype and on the genetic background of affected girls. This study aimed to systematically investigate the key clinical features of TS in relationship to karyotype in a large pediatric Turkish patient population. Methods: Our retrospective study included 842 karyotype-proven TS patients aged 0-18 years who were evaluated in 35 different centers in Turkey in the years 2013-2014. Results: The most common karyotype was 45,X (50.7%), followed by 45,X/46,XX (10.8%), 46,X,i(Xq) (10.1%) and 45,X/46,X,i(Xq) (9.5%). Mean age at diagnosis was 10.2±4.4 years. The most common presenting complaints were short stature and delayed puberty. Among patients diagnosed before age one year, the ratio of karyotype 45,X was significantly higher than that of other karyotype groups. Cardiac defects (bicuspid aortic valve, coarctation of the aorta and aortic stenosis) were the most common congenital anomalies, occurring in 25% of the TS cases. This was followed by urinary system anomalies (horseshoe kidney, double collector duct system and renal rotation) detected in 16.3%. Hashimoto’s thyroiditis was found in 11.1% of patients, gastrointestinal abnormalities in 8.9%, ear nose and throat problems in 22.6%, dermatologic problems in 21.8% and osteoporosis in 15.3%. Learning difficulties and/or psychosocial problems were encountered in 39.1%. Insulin resistance and impaired fasting glucose were detected in 3.4% and 2.2%, respectively. Dyslipidemia prevalence was 11.4%. Conclusion: This comprehensive study systematically evaluated the largest group of karyotype-proven TS girls to date. The karyotype distribution, congenital anomaly and comorbidity profile closely parallel that from other countries and support the need for close medical surveillance of these complex patients throughout their lifespan.

The role of leptin, soluble leptin receptor, adiponectin and visfatin in insulin sensitivity in preterm born children in prepubertal ages.

BACKGROUND There are still controversies whether insulin resistance (IR) develops in preterm born children during early childhood. OBJECTIVE To investigate the role of leptin, soluble leptin receptor (sOB-R), adiponectin, visfatin and insulin sensitivity in the pathogenesis of possible IR in preterm born children during early childhood. PATIENTS AND METODS Twenty-nine preterm small for gestational age (SGA) born children (Group 1) and 25 preterm appropriate for gestational age (AGA) born children (Group 2), matched for gestational age and sex were included in the study. Mean chronological age at investigation was 3.3±0.7years and not different between the groups. Blood samples for fasting blood glucose, insulin, proinsulin, adiponectin, leptin, sOB-R and visfatin were obtained. RESULTS Mean height and weight standard deviation scores (SDS) at investigation were significantly lower in Group 1 than in Group 2, but there was no significant difference in body mass index (BMI) SDS between the groups. Catch-up growth (CUG) was higher in Group 1 than in Group 2. There was no difference regarding homeostasis model assessment for IR (HOMA-IR), leptin, sOB-R, adiponectin, proinsulin and visfatin values between the groups. In the whole group, log visfatin showed a negative correlation with Δweight SDS. There was a positive correlation between HOMA-IR and BMI SDS. Adiponectin levels showed a positive correlation with log visfatin levels in all groups. CONCLUSION Preterm born children whether AGA or SGA do not show IR in early childhood if BMI is normal. Significant differences between the preterm SGA and preterm AGA groups regarding the adipocytokine levels were not detected.

Permanent Neonatal Diabetes Mellitus: Same Mutation, Different Glycemic Control with Sulfonylurea Therapy on Long-Term Follow-up

Permanent neonatal diabetes mellitus (PNDM) is a rare condition presenting before six months of age. Mutations in the genes encoding the ATP-sensitive potassium (KATP) channel are the most common causes. Sulfonylurea (SU) therapy leads to dramatic improvement in diabetes control and quality of life in most patients who carry these mutations. Here, we report the long-term follow-up results of two siblings with PNDM who were treated with insulin until ABCC8 gene mutation was identified, and were successfully transferred to oral SU therapy. After 3.5 years of follow-up on SU, one patient had a very good response, while the other one had a poor response. Bad compliance to diet was thought to be the most probable reason for poor glycemic control in this patient. In conclusion, molecular genetic diagnosis in all patients with PNDM is recommended. Compliance to treatment should be an important aspect of the follow-up of these patients. Conflict of interest:None declared.

Anthropometric findings from birth to adulthood and their relation with karyotpye distribution in Turkish girls with Turner syndrome

To evaluate the anthropometric features of girls with Turner syndrome (TS) at birth and presentation and the effect of karyotype on these parameters. Data were collected from 842 patients with TS from 35 different centers, who were followed‐up between 1984 and 2014 and whose diagnosis age ranged from birth to 18 years. Of the 842 patients, 122 girls who received growth hormone, estrogen or oxandrolone were excluded, and 720 girls were included in the study. In this cohort, the frequency of small for gestational age (SGA) birth was 33%. The frequency of SGA birth was 4.2% (2/48) in preterm and 36% (174/483) in term neonates (P < 0.001). The mean birth length was 1.3 cm shorter and mean birth weight was 0.36 kg lower than that of the normal population. The mean age at diagnosis was 10.1 ± 4.4 years. Mean height, weight and body mass index standard deviation scores at presentation were −3.1 ± 1.7, −1.4 ± 1.5, and 0.4 ± 1.7, respectively. Patients with isochromosome Xq were significantly heavier than those with other karyotype groups (P = 0.007). Age at presentation was negatively correlated and mid‐parental height was positively correlated with height at presentation. Mid‐parental height and age at presentation were the only parameters that were associated with height of children with TS. The frequency of SGA birth was found higher in preterm than term neonates but the mechanism could not be clarified. We found no effect of karyotype on height of girls with TS, whereas weight was greater in 46,X,i(Xq) and 45,X/46,X,i(Xq) karyotype groups.