Iodine Status in Cyprus and Neighboring Countries: A Review Article

Despite the implementation of global iodine supplementation initiatives in the past decade, the problem of iodine deficiency persists as a significant public health concern in numerous countries. Although cretinism is now rare in developed countries, iodine deficiency can still lead to less severe cognitive deficits, which can negatively impact academic achievement, intellectual capacity, and work productivity. There is a scarcity of studies regarding the status of Cyprus, and the global database does not have any information pertaining to the prevalence of iodine deficiency in Cyprus. The geographical setting of the research is of importance as it pertains to the separation of Cyprus into two distinct areas. One region is predominantly inhabited by Greek Cypriots, where the practice of salt iodization is not mandatory. Conversely, the other region is primarily inhabited by Turkish Cypriots, who may potentially experience higher amounts of iodine contact due to their reliance on food imports from Turkey, where salt-iodisation is compulsory. The main objective of this study is to provide an overview of recent research conducted on the prevalence of iodine deficiency in Cyprus and neighboring Mediterranean nations. In this study, we assess the current method and subsequently offer public health recommendations for future research endeavors.

Molecular diagnosis in patients with monogenic diabetes mellitus, and detection of a novel candidate gene

AIM

We aimed to investigate molecular genetic basis of monogenic diabetes (DM) and novel responsible candidate genes with targeted Next Generation Sequencing (NGS) and Whole Exome Sequencing (WES).

METHODS

A hundred cases presenting with clinical findings and a family history of monogenic DM were included in the study. Molecular analysis was performed using an NGS panel including 14 genes. Following targeted NGS, WES was planned in cases in whom no variant was detected.

RESULTS

Thirty different disease-causing variants in seven different genes were detected in thirty-five (35 %) cases with targeted NGS approach. Most common pathogenic variant was found in GCK gene in 25 (25 %) cases. Four different variants were detected in 4 (4 %) patients in ABCC8 gene. In 45 of 65 cases; WES analyses were done. A heterozygous c.2635C > T(p.Gln879Ter) variant was detected in IFIH1 gene in a patient with incidental hyperglycemia. In the segregation analysis affected mother was shown to be heterozygous for the same variant.

CONCLUSION

Molecular etiology was determined in 35 % cases with the NGS targeted panel. Seventeen novel variants in monogenic DM genes have been identified. A candidate gene determined by WES analysis in a case that could not be diagnosed with NGS panel in this study.

Non-Invasive Screening Test Paradox in a Case Born with Mixed Gonadal Dysgenesis (45,X/46,Xy)

Noninvasive prenatal testing (NIPT) is commonly used to screen for fetal trisomy 13, 18, and 21 and often for sex chromosomal aneuploidies (SCAs). Although the testing is also used for sex chromosomal aneuploidies, it is not as efficient as it is for common trisomies. In this particular study, we present a case for whom the NIPT diagnosis was originally 45,X and who was diagnosed with mixed gonadal dysgenesis 45,X/46,XY after birth. A 38-year-old [G3P3] pregnant woman underwent NIPT at 15 weeks' gestation and was found to be at probable risk for 45,X. Because cordocentesis is an invasive procedure, the pregnant woman did not want to undergo cordocentesis. Consequently, postnatal cytogenetic analysis was performed and the baby's karyotype was shown to be 45,X/46,X,+mar?. No numerical and/or structural anomalies were observed in the karyotypes of parents and siblings. Based on the microarray analysis of the analyzed sample, one copy of the X chromosome was detected in all cells and the presence of one copy of the Y chromosome was detected in a ~40% mosaic state: arr(X) x1,(Y)x1[0.4]. SRY gene duplication on Y chromosome was confirmed by fluorescence in situ hybridization (FISH) and microarray analysis. The patient's clinical examination showed ambiguous genitalia (clitoromegaly) and dysmorphic facial features. The baby underwent surgery for aortic coarctation. The results were consistent with a genetic diagnosis of 45,X/46,XY mixed gonadal dysgenesis. Genetic counselling was offered to the family. In conclusion, NIPT still has potential limitations in correctly identifying sex chromosomes and mosaicism that may mislead clinicians and families.

Characterization of a Novel Frameshift Mutation Within the TRPS1 Gene Causing Trichorhinophalangeal Syndrome Type 1 in a Kindred Cypriot Family

Trichorhinophalangeal syndrome (TRPS) is an extremely rare autosomal dominant multisystem disorder characterized by craniofacial and skeletal abnormalities. Three subtypes of TRPS have been described: TRPS type I, TRPS type II, and TRPS type III. Mutations in the TRPS1 gene can cause both TRPS type I and TRPS type III. Therefore, the genotype-phenotype correlation is crucial to determine the subtype. The current family study from Cyprus involves affected patients from 4 generations who presented with alopecia, unoperated umbilical hernia, caput quadratum, long philtrum, depressed nasal bridge, frontal bossing, pes planus, beaked nose, and some deformities in hands and feet. Sequence analysis of the TRPS1 gene revealed a novel c.2854_2858del (p.Asn952ArgfsTer2) frameshift variant leading to a premature stop codon. To the best of our knowledge, we report here the first case of a Turkish Cypriot family of 4 generations with a novel frameshift mutation leading to truncated protein in the TRPS1 gene causing TRPS type I clinical phenotype. Overall, as the genotype and phenotype correlation in TRPSI is still uncertain and complex, the present outcome can enhance our knowledge of this complicated, rare, and severe genetic disorder.

Evaluation of the Efficacy and Safety of 3 Different Management Protocols in Pediatric Diabetic Ketoacidosis

OBJECTIVE

Management protocols for pediatric diabetic ketoacidosis (DKA) vary considerably among medical centers. The aim of this study was to investigate the efficacy and safety of 3 different fluid protocols in the management of DKA.

METHODS

Fluid management protocols with sodium contents of 75, 100, and 154 mEq/L NaCl were compared. In all groups, after the initial rehydration, the protocols differed from each other in terms of the maintenance fluid, which had different rates of infusion and sodium contents. Clinical status and blood glucose levels were checked every hour during the first 12 hours. Biochemical tests were repeated at 2, 6, 12, 24, and 36 hours.

RESULTS

The medical records of 144 patients were evaluated. Cerebral edema developed in 18% of the patients. The incidence of cerebral edema was lowest in the group that received fluid therapy with a sodium content of 154 mEq/L NaCl at least 4 to 6 hours and had a constant rate of infusion for 48 hours. The patients with cerebral edema had lower initial pH and HCO3 and severe dehydration with higher initial plasma osmolality. There was no significant difference between the groups in terms of the recovery times of blood glucose, pH, HCO3, and the time of transition to subcutaneous insulin therapy.

CONCLUSIONS

Severity of acidosis and dehydration are associated with the development of cerebral edema. It can be concluded that fluid therapy with higher Na content and a constant maintenance rate may present less risk for the patient with DKA.

Identification of a Novel De Novo COMP Gene Variant as a Likely Cause of Pseudoachondroplasia

Next-generation sequencing technology and advanced sequence analysis techniques are markedly speeding up the identification of gene variants causing rare genetic diseases. Pseudoachondroplasia (PSACH, MIM 177170) is a rare disease inherited in an autosomal dominant manner. It is known that variations in the cartilage oligomeric matrix protein (COMP) gene are associated with the disease. Here, we report a 39-month-old boy with short stature. He gave visible growth and development delayed phenotype after 12 months. Further genetic resequencing analysis was carried out to identified the disease-causing variant. Furthermore, computational approaches were used to characterize the effect of the variant. In this study, we identify and report a novel variation in the COMP gene, c.1420_1422del (p.Asn47del), causing a spontaneous form of PSACH in our patient. Our in silico model indicated that any mutational changes in this region are very susceptible to PASCH phenotype. Overall, this study is the first PSACH case in the Turkish Cypriot population. Moreover, this finding contributes to the concept that the genotype-phenotype correlation in COMP is still unknown and also improves our understanding of this complex disorder.

Unusual Glycemic Presentations in a Child with a Novel Heterozygous Intragenic INSR Deletion

BACKGROUND

Mutations of the insulin receptor (INSR) gene lead to a wide spectrum of inherited insulin resistance (IR) syndromes. Among these, type A-IR, usually caused by dominant negative INSR mutations, generally presents peri-pubertally in girls.

CASE

A 2.8-year-old girl was referred due to recurrent postprandial and fasting hypoglycemia. She had been born at full-term with birth weight 1.89 kg, and had developed transient neonatal diabetes. Examination showed satisfactory growth, reduced adipose tissue, acanthosis nigricans, and isolated thelarche. After 12 h of fasting, she developed hypoglycemia (glucose 2.8 mmol/L), with inappropriately raised plasma insulin concentration of 5.4 mU/L and suppressed fatty acids and ketone bodies. Oral glucose tolerance testing showed severely increased plasma insulin concentration (>300 mU/L) with hypoglycemia (glucose 1.6 mmol/L) at 2.5 h. She was initially managed on dietary modifications, cornstarch, and then trialed on acarbose for postprandial hyperinsulinemic hypoglycemia (PPHH) with some response. However, she was noted to have increased frequency of hyperglycemia after a couple of years of treatment. She was then switched to metformin and continued to have dietary carbohydrate modification including cornstarch that improved fasting tolerance, hyperglycemia, and postprandial hypoglycemia. Genetic testing identified heterozygous deletion of the last exon of the INSR gene, exon 22.

CONCLUSION

We present a case of type A-IR, caused by a novel INSR deletion, presenting unusually early with transient neonatal diabetes, followed by episodes of hypoglycemia and hyperglycemia during later childhood. Early life presentations, including neonatal diabetes and PPHH, should lead to consideration of type A-IR.

Evidence in obese children: contribution of tri-ponderal mass index or body mass index to dyslipidemia, obesity-inflammation, and insulin sensitivity

Background Chronic inflammation plays a critical role in the development of obesity-related metabolic dysfunction. The tri-ponderal mass index (TMI) may be more effective than body mass index (BMI) for estimating body fat levels. This study compared the efficacy of BMI and TMI in screening for dyslipidemia, insulin sensitivity, and inflammation in childhood obesity. Methods This study included 80 children who were classified as normal weight, overweight or obese using standardized BMI (BMI standard deviation score [SDS]) and TMI measurements. Fasting blood glucose, insulin, homeostasis model assessment of insulin resistance (HOMA-IR), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C), triglycerides, total cholesterol, liver function enzymes, leptin, serum free fatty acid (FFA), fetuin-A, monocyte chemoattractant protein-1 (MCP-1), tumor necrosis factor-alpha (TNF-α), and interleukin (IL)-6 levels were evaluated using both classification systems. Results LDL-C levels significantly differed within the groups by BMI, and serum FFA levels differed only according to the TMI. Serum MCP-1, TNF-α, IL-6, and fetuin-A levels showed no difference according to the TMI or BMI SDS. Fetuin-A levels did not differ between the insulin-resistant and non-resistant cases. Fetuin-A was the only inflammatory marker positively correlated with BMI. No inflammatory markers correlated with TMI. Fetuin-A, MCP-1, TNF-α, and IL-6 correlated with each other, but not with metabolic parameters. Conclusions BMI SDS and TMI were associated with metabolic disturbances in childhood obesity. Weight versus heightn values may be related more to metabolic parameters than to inflammatory changes.

Headliner in Physiology and Management of Childhood Asthma: Hypothalamic-Pituitary-Adrenal Axis

Asthma is the most common chronic inflammatory disease of children. Inhaled corticosteroids (ICS) are the cornerstone of asthma therapy which are the most effective, commonly used treatment of persistent asthma. Mostly, studies on the relationship between asthma and cortisol have focused on side effects of treatment. Recently, asthmatic patients not treated with ICS have been reported to have an attenuated activity and/or responsiveness of their Hypothalamic-Pituitary- Adrenal (HPA) axis. Moreover, it has been proposed that asthma worsening with stress may be due to a dysfunctional HPA axis, or cortisol insensitivity due to chronic psychological stress through impaired glucocorticoid receptor expression or function. Although long-term ICS treatment might produce adrenal suppression or iatrogenic Cushing syndrome, improvement of adrenal function has also been detected in some of asthmatic cases. Thus, the response scheme of HPA axis still contains undiscovered features in asthma. The management of asthma can be improved by increasing knowledge on the role of HPA axis in asthma pathophysiology. The risk for side effects of ICS can be minimized through increased awareness, early recognition of at-risk patients and regular patient follow-up. This review was written to draw attention to the role of HPA axis in both asthma and its treatment and to illustrate a follow up algorithm of HPA axis in the management of asthma.

Joubert syndrome with multiple pituitary hormone deficiency

Joubert syndrome (JS) and JS-related disorders are a group of developmental delay, multiple congenital anomalies and complex midbrain-hindbrain malformations. A few cases of JS with multiple pituitary hormone deficiency (MPHD) have been reported in literature. Here, we presented an unusual presentation of JS in a newborn with MPHD. This case is intended to draw attention to the rare association of JS and MDPH by increasing the awareness of this syndrome.

A Novel TBX19 Gene Mutation in a Case of Congenital Isolated Adrenocorticotropic Hormone Deficiency Presenting with Recurrent Respiratory Tract Infections

INTRODUCTION

Congenital isolated adrenocorticotropic hormone deficiency (CIAD) is a rare disease characterized by low adrenocorticotropic hormone (ACTH) and cortisol levels. To date, recurrent pulmonary infections in infancy have not been reported as an accompanying symptom of CIAD.

CASE PRESENTATION

A 7-year-old boy was hospitalized nine times for recurrent lower respiratory tract infections. The results of all tests for the possible causes of wheezing were within the normal limits. His ACTH and cortisol levels were persistently low. All other pituitary hormone levels, and adrenal ultrasound and pituitary magnetic resonance imaging results, were normal. Molecular analyses confirmed the diagnosis of CIAD by identifying compound heterozygosity for two mutations in the TBX19 gene. The first was a novel frameshift c.665delG variant in exon 4 of the TBX19 gene, leading to premature termination that was predicted to result in a non-functional truncated protein. The second was a nonsense C-to-T transition in exon 6 of the TBX19 gene, resulting in an arg286-to-ter mutation (dbSNP: rs74315376). Both parents were heterozygous for one of the mutations.

CONCLUSION

Here, we presented a new mutation in the TBX19 gene in a patient with CIAD who presented with recurrent respiratory tract infections. This expands the mutation spectrum in this disorder. To conclude, adrenal insufficiency should be considered in patients with unexplained recurrent infections to prevent a delay in diagnosis.