Hüseyin Anıl Korkmaz

The effect of antiepileptic drugs on thyroid function in children

BACKGROUND Limited and conflicting data exist for the influence of antiepileptic drugs on thyroid function in children. OBJECTIVE The aim of this study was to investigate the effects of phenobarbital, valproate, carbamazepine, oxcarbazepine, and levetiracetam monotherapy on thyroid function in daily clinical practice during a 12-month treatment period. METHOD A total of 223 children (103 females and 120 males) with new onset and controlled epilepsy treated with valproate (n=129), phenobarbital (n=33), carbamazepine (n=36), oxcarbazepine (n=14), levetiracetam (n=11) were enrolled in the study. Serum free thyroxine (fT4) and thyroid-stimulating hormone (TSH) levels were measured before and at first, sixth and twelfth months of therapy. RESULTS At baseline, average fT4 and TSH concentrations were not different between the drug groups. Valproate-treated patients had decreased fT4 and increased TSH levels at months 1, 6, and 12. Carbamazepine-treated patients had decreased fT4 levels at months 1, 6, and 12 and increased TSH levels at months 1, and 6. Phenobarbital-treated patients had decreased fT4 levels at months 1, and 6, and increased TSH levels at months 6 and 12. Oxcarbazepine-treated patients had decreased fT4 levels at month 1. Levetiracetam-treated patients showed no significant change of fT4 and TSH at any times. The frequency of subclinical hypothyroidism at month 12 was 28% in valproate, 21.4% in oxcarbazepine, 18.2% in phenobarbital, 13.9% in carbamazepine, and 0% in levetiracetam groups. CONCLUSION Our data suggest that all antiepileptic drugs studied except levetiracetam had varying degrees of deleterious effects on thyroid function.

Can neutrophil/lymphocyte ratio be a novel biomarker of inflammation in children with asthma?

Neutrophils are known to play a role in airway inflammation and are activated in inflammatory lung diseases such as asthma. In adult studies the neutrophil/lymphocyte ratio (NLR) was found to be a possible biomarker for both airway and systemic inflammation. However, there is a limited understanding regarding NLR in the pediatric age group. To assess NLR as a biomarker for inflammation in pediatric asthma, 54 children admitted to hospital with exacerbation of asthma between March and October 2013 were enrolled into our study. Complete blood counts were obtained during both exacerbation and an asymptomatic period covering at least 3 months after exacerbation. NLRs of the study group during both exacerbation and the asymptomatic period were compared and these two datasets were then compared with the control group. The study group comprised 27 boys (50%) and 27 girls (50%) with a mean age of 120 ± 36 months. Of the total number of patients, 3.7% had mild, 94.4% had moderate, and 1.9% had severe exacerbation of asthma. The NLRs of the study group were found to be significantly higher during exacerbation compared with both the asymptomatic period and the control group (P = 0.017, P = 0.003). Our study suggests that NLR may be effective and usable measurable biomarker for determining inflammation in cases of pediatric asthma during acute exacerbation period. However, a broad analysis of dependent and independent variables in further prospective studies, is still required. Trial registration: Not applicable.

Molecular diagnosis of maturity-onset diabetes of the young (MODY) in Turkish children by using targeted next-generation sequencing.

Abstract Aim: To perform molecular analysis of pediatric maturity onset diabetes of the young (MODY) patients by next-generation sequencing, which enables simultaneous analysis of multiple genes in a single test, to determine the genetic etiology of a group of Turkish children clinically diagnosed as MODY, and to assess genotype-phenotype relationship. Methods: Forty-two children diagnosed with MODY and their parents were enrolled in the study. Clinical and laboratory characteristics of the patients at the time of diagnosis were obtained from hospital records. Molecular analyses of GCK, HNF1A, HNF4A, HNF1B, PDX1, NEUROD1, KLF11, CEL, PAX4, INS, and BLK genes were performed on genomic DNA by using next-generation sequencing. Pathogenicity for novel mutations was assessed by bioinformatics prediction software programs and segregation analyses. Results: A mutation in MODY genes was identified in 12 (29%) of the cases. GCK mutations were detected in eight cases, and HNF1B, HNF1A, PDX1, and BLK mutations in the others. We identified five novel missense mutations – three in GCK (p.Val338Met, p.Cys252Ser, and p.Val86Ala), one in HNF1A (p.Cys241Ter), and one in PDX1 (p.Gly55Asp), which we believe to be pathogenic. Conclusion: The results of this study showed that mutations in the GCK gene are the leading cause of MODY in our population. Moreover, genetic diagnosis could be made in 29% of Turkish patients, and five novel mutations were identified.

Management of central diabetes insipidus with oral desmopressin lyophilisate in infants

Abstract Aim: To assess the efficiency of oral desmopressin lyophilisate (ODL) in neonatal central diabetes insipidus (CDI). Methods: The characteristics of four newborns with CDI treated with ODL were evaluated. Results: Four newborns with polyuria and hypernatremia were included [male, 2 (50%); mean postnatal age, 19±17 days]. At the time of hypernatremia, the mean serum and urine osmolality values were 310±16 and 179±48 mOsm/kg, respectively. Antidiuretic hormone levels were undetectable (<0.5 pmol/L) in all cases. Magnetic resonance imaging revealed anatomical malformations in all cases. ODL (60 μg/tablet) dissolved in water (3–5 mL) was initiated with a dose of 5 μg/kg/day in two equal doses, together with limitation of water intake to avoid hyponatremia. Serum sodium levels returned to normal in a mean duration of 58±9.9 h with a mean decline rate of 0.37±0.1 mEq/L/h after desmopressin administration. Rehospitalization was required for one of the infants because of hypernatremia due to non-compliance. No episode of hyponatremia was encountered. Weight gain and growth of the infants were normal during the mean follow-up duration of 8.5±1 months. Conclusions: ODL appears to be practical and safe in the treatment of CDI during the first year of life.

Impact of insulin resistance on insulin-like growth factor-1/insulin like growth factor-binding protein-3 axis and on early weight gain in small for gestational age infants.

Objective: To assess insulin-like growth factor-1 (IGF-1)/IGF-binding protein-3 (IGFBP-3) axis and insulin resistance (IR) and the relationship of these parameters with growth in appropriate for gestational age (AGA) and small for gestational age (SGA) infants at birth and in early infancy. Methods: Postnatal blood samples for measurement of glucose, insulin, IGF-1, and IGFBP-3 were taken from 60 infants (30 AGA and 30 SGA) at birth and at one, three, and six months of age. Both SGA and AGA infants were divided into two groups: growing well and not growing well. Blood glucose, insulin, IGF-1, and IGFBP-3 values were assessed in all infants. Results: Homeostasis model assessment-IR (HOMA-IR) values in well-growing SGA infants in the third and sixth months were found to be higher than in not well-growing SGA infants (3.9±0.8 vs. 1.0±0.3 at 3 months and 3.3±0.9 vs. 2.4±0.9 at 6 months, p<0.05). IGF-1 levels in well-growing SGA infants at 3 and 6 months were found to be higher than those in not well-growing SGA infants (83.80±44.50 vs. 73.50±17.60 ng/mL at 3 months and 95.12±50.74 vs. 87.67±22.91 ng/mL at 6 months, p<0.05). The IGF-1 values were significantly lower in well-growing SGA infants than in well-growing AGA infants (83.80±44.50 vs. 103.31±30.81 ng/mL at 3 months and 95.12±50.74 vs. 110.87±26.44 ng/mL at 6 months, p<0.05). Conclusions: This study demonstrates the effects of accelerated early infant growth on IGF-1/IGFBP-3 axis in SGA-born infants. Conflict of interest:None declared.

Neonatal seizure as a manifestation of unrecognized maternal hyperparathyroidism.

Maternal hypercalcemia suppresses parathyroid activity in the fetus resulting in impaired parathyroid responsiveness to hypocalcemia after birth. Resultant hypocalcemia may be severe and prolonged and rarely may lead to convulsions. Here, we present a newborn infant admitted to the pediatric emergency department at age two weeks with recurrent tonic convulsions due to asymptomatic maternal hyperparathyroidism and vitamin D deficiency. Physicians should be aware that undiagnosed maternal hyperparathyroidism can cause severe hypocalcemia in the newborn. Conflict of interest:None declared.

A novel mutation of AMH in three siblings with persistent Mullerian duct syndrome

Abstract Background: Persistent Mullerian duct syndrome (PMDS) is a rare form of male 46,XY disorder of sex development characterized by the presence of Mullerian duct derivatives in otherwise phenotypically normal males. Aim: To report a novel mutation of the anti-Mullerian hormone (AMH) gene in two of three siblings with PMDS. Cases: A 2-year-old male presented with recurrent left-sided inguinal hernia and absence of right testis. Laparoscopic surgery disclosed Mullerian duct derivates and transverse testicular ectopia. AMH level was found to be low [1.6 ng/mL (normal range 7.4–373.1), 11.42 pmol/L (normal range 52.8–2663.9)]. His 15-year-old and 7-year-old elder brothers were invited, and bilateral undescended testes were noted upon examination. Female reproductive structures were identified during surgery but no transverse testicular ectopia. All cases had 46,XY karyotype. Genetic analyses could be done in two of them and a unique homozygous T to C base substitution was found at position 1591 in the AMH gene. Conclusion: This is the first report of the AMH gene mutation which is referred as p.Y531H (c.1591T>C), which resulted in different phenotypes of PMDS in three siblings.

Genetic variants of estrogen beta and leptin receptors may cause gynecomastia in adolescent

OBJECTIVE Gynecomastia is a benign breast enlargement in males that affects approximately one-third of adolescents. The exact mechanism is not fully understood; however, it has been proposed that estrogen receptors and aromatase enzyme activity may play important roles in the pathogenesis of gynecomastia. While many studies have reported that aromatase enzyme (CYP19) gene polymorphism is associated with gynecomastia, only one study has shown a relationship between estrogen receptor (ER) alpha and beta gene polymorphism and gynecomastia. Thus, the aim of this study was to evaluate the relationships between CYP19 (rs2414096), ER alpha (rs2234693), ER beta (rs4986938), leptin (rs7799039), and leptin receptor (rs1137101) gene polymorphisms and gynecomastia. METHODS This study included 107 male adolescents with gynecomastia and 97 controls. Total serum testosterone (T) and estradiol (E2) levels were measured, and DNA was extracted from whole blood using the PCR-RFLP technique. The polymorphic distributions of CYP19, ER alpha, ER beta, leptin and leptin receptor genes were compared. RESULTS The median E2 level was 12.41 (5.00-65.40) pg/ml in the control group and 16.86 (2.58-78.47) pg/ml in the study group (p<0.001). The median T level was 2.19 (0.04-7.04) ng/ml in the control group and 1.46 (0.13-12.02) ng/ml in the study group (p=0.714). There was a significant relationship between gynecomastia and leptin receptor rs1137101 (p=0.002) and ER beta receptor rs4986938 gene polymorphisms (p=0.002). CONCLUSIONS According to our results, increased E2 level and ER beta gene rs4986938 polymorphism might explain why some adolescents have gynecomastia. Leptin receptor gene rs1137101 polymorphism might affect susceptibility to gynecomastia.

Hypochondroplasia in a Child with 1620C>G (Asn540Lys) Mutation in FGFR3

Hypochondroplasia (HCP) is an autosomal dominant skeletal dysplasia characterized by short extremities, short stature and lumbar lordosis, usually exhibiting a phenotype similar to but milder than achondroplasia (ACP). Fibroblast growth factor receptor 3 gene (FGFR3) mutations in the germline are well-known causes of skeletal syndromes. FGFR3 is a negative regulator of bone growth and all mutations in FGFR3 are gain-of-function mutations that lead to skeletal dysplasias. We report a child who presented with short stature, a relatively long trunk, short legs, short arm span, radiographic evidence of HCP and mild mental retardation. Genetic analysis revealed a heterozygous 1620C>G (Asn540Lys) mutation in FGFR3. To our knowledge, ours is the first case report of HCP with a heterozygous 1620C>G (Asn540Lys) mutation in Turkey. Conflict of interest:None declared.

Two different patterns of mini-puberty in two 46,XY newborns with 17β-hydroxysteroid dehydrogenase type 3 deficiency.

Abstract We report two newborns with female external genitalia and bilateral inguinal swelling who were diagnosed with 17β-hydroxysteroid dehydrogenase type 3 deficiency, a rare cause of 46,XY disorder of sexual development. The first case had normal clitoral size and vaginal and urethral openings, palpable gonads in the inguinal region, low testosterone, and low levels of basal and GNRH-stimulated gonadotropin. The second case had similar external genitalia, low testosterone but borderline basal and normal stimulated gonadotropin levels. Low testosterone/androstenedione ratios (0.22 and 0.24, respectively; normal, >0.8) after human chorionic gonadotropin stimulation indicated 17β-hydroxysteroid dehydrogenase type 3 deficiency. HSD17B3 sequencing revealed a homozygous novel mutation (c.464A>C, p.H155P) in exon 6 in the first case and homozygous c.239G>A (p.R80Q) in exon 3 in the second.