Serum kisspeptin, neurokinin B and inhibin B levels can be used as alternative parameters to distinguish idiopathic CPP from premature thelarche in the early stages of puberty.

OBJECTIVE: There is controversial results about serum kisspeptin, neurokinin-B (NKB), anti-Müllerian hormone (AMH) and inhibin B (INHB) levels in girls with central precocious puberty (CPP). Aim of this study is to evaluate serum levels of these four peptides in patients presented with early pubertal signs, and to evaluate their diagnostic validity in the diagnosis of CPP. DESIGN: Cross-sectional study. PATIENTS: Study included 99 girls (51 CPP, 48 premature thelarche [PT]) whose breast development started before 8 years and 42 age-matched healthy prepubertal girls. Clinical findings, antropometric measurements, laboratory and radiological findings were recorded. Gonadotropin-releasing hormone (GnRH) stimulation test was performed in all cases with early breast development. MEASUREMENTS: Kisspeptin, NKB, INHB and AMH levels were measured in fasting serum samples using enzyme-linked immunosorbent assay method. RESULTS: There was no statistically significant difference between mean ages of girls with CPP (7.1 ± 1.2 years), PT (7.2 ± 1.3 years) and prepubertal controls (7.0 ± 1.0 years). Serum kisspeptin, NKB and INHB levels were higher in CPP group compared to PT and control groups, while serum AMH level was lower in CPP group. Serum kisspeptin, NKB, and INHB were all positively correlated with bone age (BA) advancement, and peak luteinizing hormone in GnRH test. Multiple stepwise regression analysis revealed that the most important factors used to differentiate CPP from PT were advanced BA, serum kisspeptin, NKB and INHB levels (AUC: 0.819, p < .001). CONCLUSIONS: We, first showed in the same patients' group that serum kisspeptin, NKB and INHB were higher in patients with CPP and can be used as alternative parameters to distinguish CPP from PT.

Systematic genetic testing for recessively inherited monogenic diabetes: a cross-sectional study in paediatric diabetes clinics.

AIMS/HYPOTHESIS: Current clinical guidelines for childhood-onset monogenic diabetes outside infancy are mainly focused on identifying and testing for dominantly inherited, predominantly MODY genes. There are no systematic studies of the recessively inherited causes of monogenic diabetes that are likely to be more common in populations with high rates of consanguinity. We aimed to determine the contribution of recessive causes of monogenic diabetes in paediatric diabetes clinics and to identify clinical criteria by which to select individuals for recessive monogenic diabetes testing. METHODS: We conducted a cross-sectional study of 1093 children from seven paediatric diabetes clinics across Turkey (a population with high rates of consanguinity). We undertook genetic testing of 50 known dominant and recessive causes of monogenic diabetes for 236 children at low risk of type 1 diabetes. As a comparison, we used monogenic diabetes cases from UK paediatric diabetes clinics (a population with low rates of consanguinity). RESULTS: Thirty-four children in the Turkish cohort had monogenic diabetes, equating to a minimal prevalence of 3.1%, similar to that in the UK cohort (p = 0.40). Forty-one per cent (14/34) had autosomal recessive causes in contrast to 1.6% (2/122) in the UK monogenic diabetes cohort (p < 0.0001). All conventional criteria for identifying monogenic diabetes (parental diabetes, not requiring insulin treatment, HbA1c ≤ 58 mmol/mol [≤7.5%] and a composite clinical probability of MODY >10%) assisted the identification of the dominant (all p ≤ 0.0003) but not recessive cases (all p ≥ 0.2) in Turkey. The presence of certain non-autoimmune extra-pancreatic features greatly assisted the identification of recessive (p < 0.0001, OR 66.9) but not dominant cases. CONCLUSIONS/INTERPRETATION: Recessively inherited mutations are a common cause of monogenic diabetes in populations with high rates of consanguinity. Present MODY-focused genetic testing strategies do not identify affected individuals. To detect all cases of monogenic paediatric diabetes, it is crucial that recessive genes are included in genetic panels and that children are selected for testing if they have certain non-autoimmune extra-pancreatic features in addition to current criteria.

Clinical, biochemical, and echocardiographic evaluation of neonates with vitamin D deficiency due to maternal vitamin D deficiency.

OBJECTIVE: There are a few number of case reports and small-scale case series reporting dilated cardiomyopathy due to vitamin D-deficient rickets. The present study evaluates the clinical, biochemical, and echocardiographic features of neonates with vitamin D deficiency. PATIENTS AND METHODS: In this prospective single-arm observational study, echocardiographic evaluation was performed on all patients before vitamin D3 and calcium replacement. Following remission of biochemical features of vitamin D deficiency, control echocardiography was performed. Biochemical and echocardiographic characteristics of the present cohort were compared with those of 27 previously published cases with dilated cardiomyopathy due to vitamin D deficiency. RESULTS: The study included 148 cases (95 males). In the echocardiographic evaluation, none of the patients had dilated cardiomyopathy. All of the mothers were also vitamin D deficient and treated accordingly. Comparison of patients with normocalcaemia and hypocalcaemia at presentation revealed no statistically significant difference between the ejection fraction and shortening fraction, while left ventricle end-diastolic diameter and left ventricle end-systolic diameter were higher in patients with hypocalcaemia. Previously published historical cases were older and had more severe biochemical features of vitamin D deficiency. CONCLUSION: To the best of our knowledge, in this first and largest cohort of neonates with vitamin D deficiency, we did not detect dilated cardiomyopathy. Early recognition and detection before developing actual rickets and preventing prolonged hypocalcaemia are critically important to alleviate cardiac complications.

Neonatal diabetes due to homozygous INS gene promoter mutations: Highly variable phenotype, remission and early relapse during the first 3 years of life.

Neonatal diabetes mellitus (NDM) is a rare form of monogenic diabetes presenting within the first 6 months of life. INS gene promoter mutations have been shown to cause both remitting/relapsing and permanent NDM. We, herein, present three interesting patients with INS gene promoter mutations. Two cousins with an identical homozygous c.-331C > G mutation presented with NDM. The first cousin had nonremitting diabetes and still requires multidose insulin injections at the current age of 6.1 years. However, the other cousin's diabetes remitted at the age of 9 months, and she is still in remission at the age of 3 years with no medication or dietary intervention required (latest HbA1c was 4.9%). The third patient had NDM also due to a homozygous INS promoter c.-331C>A mutation. Her diabetes remitted at the age of 2 months and relapsed at the age of 2.6 years with severe diabetic ketoacidosis (DKA). Distinct clinical phenotype and relapse with severe DKA in one of the three cases suggest that INS promotor mutations can cause a heterogeneous phenotype and even cases exhibiting remission can relapse unpredictably. Therefore, as the age of relapse is unpredictable, close follow-up and family education on diabetes symptoms are essential for cases with remitting/relapsing diabetes due to INS gene mutations.

Ion Transporters, Channelopathies, and Glucose Disorders.

Ion channels and transporters play essential roles in excitable cells including cardiac, skeletal and smooth muscle cells, neurons, and endocrine cells. In pancreatic beta-cells, for example, potassium KATP channels link the metabolic signals generated inside the cell to changes in the beta-cell membrane potential, and ultimately regulate insulin secretion. Mutations in the genes encoding some ion transporter and channel proteins lead to disorders of glucose homeostasis (hyperinsulinaemic hypoglycaemia and different forms of diabetes mellitus). Pancreatic KATP, Non-KATP, and some calcium channelopathies and MCT1 transporter defects can lead to various forms of hyperinsulinaemic hypoglycaemia (HH). Mutations in the genes encoding the pancreatic KATP channels can also lead to different types of diabetes (including neonatal diabetes mellitus (NDM) and Maturity Onset Diabetes of the Young, MODY), and defects in the solute carrier family 2 member 2 (SLC2A2) leads to diabetes mellitus as part of the Fanconi-Bickel syndrome. Variants or polymorphisms in some ion channel genes and transporters have been reported in association with type 2 diabetes mellitus.

Permanent neonatal diabetes mellitus and neurological abnormalities due to a novel homozygous missense mutation in NEUROD1.

The basic helix-loop-helix (bHLH) transcription factor, neuronal differentiation 1 (NEUROD1) (also known as BETA2) is involved in the development of neural elements and endocrine pancreas. Less than 10 reports of adult-onset non-insulin-dependent diabetes mellitus (NIDDM) due to heterozygous NEUROD1 mutations and 2 cases with permanent neonatal diabetes mellitus (PNDM) and neurological abnormalities due to homozygous NEUROD1 mutations have been published. A 13 year-old female was referred to endocrine department due to hyperglycemia. She was on insulin therapy following a diagnosis of neonatal diabetes mellitus (NDM) at the age of 9-weeks but missed regular follow-up. Parents are second cousin. There was a significant family history of adult onset NIDDM including patient's father. Auxological measurements were within normal ranges. On laboratory examination blood glucose was 33.2 mmol/L with undetectable c-peptide and glycosylated hemoglobin level of 8.9% (73.8 mmol/mol). She had developed difficulty in walking at the age of 4 years which had worsened over time. On further evaluation, a diagnosis of visual impairment, mental retardation, ataxic gait, retinitis pigmentosa and sensory-neural deafness were considered. Cranial magnetic resonance imaging revealed cerebellar hypoplasia. Molecular genetic analysis using targeted next generation sequencing detected a novel homozygous missense mutation, p.Ile150Asn(c.449T>A), in NEUROD1. Both parents and 2 unaffected siblings were heterozygous for the mutation. We report the third case of PNDM with neurological abnormalities caused by homozygous NEUROD1 mutation, the first caused by a missense mutation. Heterozygous carriers of the p.Ile150Asn mutation were either unaffected or diagnosed with diabetes in adulthood. It is currently unclear whether the NEUROD1 heterozygous mutation has contributed to diabetes development in these individuals.

Phenotypic severity of homozygous GCK mutations causing neonatal or childhood-onset diabetes is primarily mediated through effects on protein stability.

Mutations in glucokinase (GCK) cause a spectrum of glycemic disorders. Heterozygous loss-of-function mutations cause mild fasting hyperglycemia irrespective of mutation severity due to compensation from the unaffected allele. Conversely, homozygous loss-of-function mutations cause permanent neonatal diabetes requiring lifelong insulin treatment. This study aimed to determine the relationship between in vitro mutation severity and clinical phenotype in a large international case series of patients with homozygous GCK mutations. Clinical characteristics for 30 patients with diabetes due to homozygous GCK mutations (19 unique mutations, including 16 missense) were compiled and assigned a clinical severity grade (CSG) based on birth weight and age at diagnosis. The majority (28 of 30) of subjects were diagnosed before 9 months, with the remaining two at 9 and 15 years. These are the first two cases of a homozygous GCK mutation diagnosed outside infancy. Recombinant mutant GCK proteins were analyzed for kinetic and thermostability characteristics and assigned a relative activity index (RAI) or relative stability index (RSI) value. Six of 16 missense mutations exhibited severe kinetic defects (RAI ≤ 0.01). There was no correlation between CSG and RAI (r(2) = 0.05, P = 0.39), indicating that kinetics alone did not explain the phenotype. Eighty percent of the remaining mutations showed reduced thermostability, the exceptions being the two later-onset mutations which exhibited increased thermostability. Comparison of CSG with RSI detected a highly significant correlation (r(2) = 0.74, P = 0.002). We report the largest case series of homozygous GCK mutations to date and demonstrate that they can cause childhood-onset diabetes, with protein instability being the major determinant of mutation severity.

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.

Severe Hypercalcemia in a Child With Acute Lymphoblastic Leukemia Relapse: Successful Management With Combination of Calcitonin and Bisphosphonate.

Hypercalcemia is a rare complication of hematological malignancy in children. An 8-year-old girl with CALLA (+) Pre-B-cell ALL developed hypercalcemia during bone marrow relapse. She had nausea, vomiting, leg pain, polyuria, polydipsia, and muscle weakness. At the time of relapse, the ionized calcium level was 1.99 mmol/L. Rehydration with 0.9% saline and furosemide and methylprednisolone (MP) treatment were used for the treatment of hypercalcemia. The serum ionized calcium level increased to 2.2 mmol/L despite hydration, furosemide, and MP treatment. Then, a single-dose pamidronate (1 mg/kg/dose) was administered. Despite pamidronate treatment, the calcium level continued to rise. Next, calcitonin at a dose of 8 IU/kg/dose, 4 doses per day, was added to the treatment. After commencement of calcitonin treatment, her ionized calcium level decreased to normal reference ranges. In conclusion, because of the postponed effect of bisphosphonate treatment, pamidronate and calcitonin combination is an effective treatment option in the early resolution of malignancy-related hypercalcemia.

Normosmic idiopathic hypogonadotropic hypogonadism due to a novel homozygous nonsense c.C969A (p.Y323X) mutation in the KISS1R gene in three unrelated families.

OBJECTIVE: The spectrum of genetic alterations in cases of hypogonadotropic hypogonadism continue to expand. However, KISS1R mutations remain rare. The aim of this study was to understand the molecular basis of normosmic idiopathic hypogonadotropic hypogonadism. METHODS: Clinical characteristics, hormonal studies and genetic analyses of seven cases with idiopathic normosmic hypogonadotropic hypogonadism (nIHH) from three unrelated consanguineous families are presented. RESULTS: One male presented with absence of pubertal onset and required surgery for severe penoscrotal hypospadias and cryptorchidism, while other two males had absence of pubertal onset. Two of four female cases required replacement therapy for pubertal onset and maintenance, whereas the other two had spontaneous pubertal onset but incomplete maturation. In sequence analysis, we identified a novel homozygous nonsense (p.Y323X) mutation (c.C969A) in the last exon of the KISS1R gene in all clinically affected cases. CONCLUSIONS: We identified a homozygous nonsense mutation in the KISS1R gene in three unrelated families with nIHH, which enabled us to observe the phenotypic consequences of this rare condition. Escape from nonsense-mediated decay, and thus production of abnormal proteins, may account for the variable severity of the phenotype. Although KISS1R mutations are extremely rare and can cause a heterogeneous phenotype, analysis of the KISS1R gene should be a part of genetic analysis of patients with nIHH, to allow better understanding of phenotype-genotype relationship of KISS1R mutations and the underlying genetic basis of patients with nIHH.

Diagnostic utility of the average peak LH levels measured during GnRH stimulation test.

OBJECTIVES: Gonadotropin-releasing hormone (GnRH) test is the gold standard test to evaluate the hypothalamus-pituitary-gonadal (HPG) axis for the diagnosis of central precocious puberty (CPP). However, the diagnosis of cases with clinical features of CPP whilst have borderline peak luteinizing hormone (LH) remain challenges. We aimed to evaluate diagnostic performance of the average of LH levels measured during GnRH stimulation test. METHODS: Cases with diagnosis of CPP and premature thelarche (PT) who had a GnRH stimulation test results were retrospectively reviewed. Anthropometric measurements (weight, height, and body mass index), age and sex-specific standard deviation scores, growth velocity, puberty stages, bone ages, serum FSH, LH, and estradiol levels were measured by electrochemiluminescence immunological method (ECLIA), and the GnRH stimulation test results, which performed by obtaining venous blood samples at basal, 20th, and 40th minutes for FSH and LH measurement, were recorded. RESULTS: A total of 76 girls (38 CPP, 38 PT) were included. We detected an average peak LH cut-off value of 4.25 IU/L with 94.7 % sensitivity and 97.4 % specificity, a 97.3 % positive predictive value, and a 94.9 % negative predictive value in GnRH test to differentiate cases with CPP from PT. CONCLUSIONS: This is the first study evaluating the diagnostic utility of the average of LH levels measured during GnRH stimulation test. We showed that the average of two LH measurements has a high diagnostic performance. Therefore, it can be used as a valid and reliable diagnostic tool for assessment of HPG axis activation, particularly for cases with a borderline peak LH level.

Type A insulin resistance syndrome due to a novel heterozygous c.3486_3503del (p.Arg1163_Ala1168del) INSR gene mutation in an adolescent girl and her mother.

Mutations in the insulin receptor (INSR) gene may present with variable clinical phenotypes. We report herein a novel heterozygous INSR mutation in an adolescent girl with type A insulin resistance syndrome and her mother.The index case was a 12-year-old girl without obesity who presented with excessive hair growth, especially in the chest and back area, and hyperpigmentation on the back of the neck (acanthosis nigricans). Acanthosis nigricans was first observed at the age of 11 years. On physical examination, the patient had acanthosis nigricans and hypertrichosis with no acne. Systolic and diastolic blood pressure measurement was within the normal range for age and sex. Laboratory tests revealed fasting hyperglycemia, fasting and postprandial hyperinsulinemia, elevated HbA1c level, and biochemical hyperandrogenemia. Fasting plasma lipids were normal. A diagnosis of type A insulin resistance syndrome was considered, and INSR gene mutation analysis was performed. Next generation sequence analysis was performed with the use of primers containing exon/exon-intron junctions in the INSR gene, and a novel heterozygous c.3486_3503delGAGAAACTGCATGGTCGC/p.Arg1163_Ala1168del change was detected in exon 19 of the INSR gene. In segregation analysis, the same variant was detected in the patient's mother, who had a milder clinical phenotype.We reported a novel, heterozygous, p.Arg1163_Ala1168del mutation in exon 19 of the INSR gene in a patient with type A insulin resistance syndrome, expanding the mutation database. The same mutation was associated with variable phenotypical severity in two subjects within the same family.

Severe Early-Onset Obesity and Diabetic Ketoacidosis due to a Novel Homozygous c.169C>T p.Arg57* Variant in CEP19 Gene.

Introduction: Early-onset severe obesity is usually the result of an underlying genetic disorder, and several genes have recently been shown to cause syndromic and nonsyndromic forms of obesity. The "centrosomal protein 19 (CEP19)" gene encodes for a centrosomal and ciliary protein. Homozygous variants in the CEP19 gene are extremely rare causes of early-onset severe monogenic obesity. Herein, we present a Turkish family with early-onset severe obesity with variable features. Methods: Sanger sequencing and whole-exome sequencing were performed to identify the genetic etiology in the family. Results: The index case was a 12-year-old female who presented with severe obesity (BMI of 62.7 kg/m2), metabolic syndrome, and diabetic ketoacidosis. Her nonidentical twin female siblings also had early-onset severe obesity, metabolic syndrome, and diabetes. In addition, one of the affected siblings had situs inversus abdominalis, polysplenia, lumbar vertebral fusion, and abnormal lateralization. A novel homozygous nonsense (c.169C>T, p. Arg57*) pathogenic variant was detected in exon 3 of the CEP19 gene in all affected members of the family. One unaffected sister and unaffected parents were heterozygous for the variant. This variant is predicted to cause a stop codon at amino acid sequence 57, leading to a truncated CEP19 protein. Discussion/Conclusion: Our study expands the phenotypical manifestations and variation database of CEP19 variants. The findings in one of our patients reaffirm its role in the assembly and function of both motile and immotile cilia.

Managing Severe Hypoglycaemia in Patients with Diabetes: Current Challenges and Emerging Therapies.

Hypoglycaemia is common in patients with diabetes mellitus and is a limiting factor for achieving adequate glycaemic control. In the vast majority of cases, hypoglycaemia develops due to the imbalance between food intake and insulin injections. As recurrent hypoglycaemia leads to significant morbidity and mortality, the recognition and immediate treatment of hypoglycaemia in diabetic patients is thus important. In the last 20 years, the introduction of improved insulin analogues, insulin pump therapy, continuous glucose monitoring (CGM), and sensor-augmented pump therapy have all made significant improvements in helping to reduce and prevent hypoglycaemia. In terms of treatment, the American Diabetes Association recommends oral glucose as the first-line treatment option for all conscious patients with hypoglycaemia. The second line of treatment (or first line in unconscious patients) is the use of glucagon. Novel formulations of glucagon include the nasal form, the Gvoke HypoPen which is a ready-to-deliver auto-injector packaged formulation and finally a glucagon analogue, Dasiglucagon. The Dasiglucagon formulation has recently been approved for the treatment of severe hypoglycaemia. It is a ready-to-use, similar to endogenous glucagon and its potency is also the same as native glucagon. It does not require reconstitution before injection and therefore ensures better compliance. Thus, significant improvements including development of newer insulin analogues, insulin pump therapy, continuous glucose monitoring (CGM), sensor-augmented pump therapy and novel formulations of glucagon have all contributed to reducing and preventing hypoglycaemia in diabetic individuals. However, considerable challenges remain as not all patients have access to diabetes technologies and to the newer glucagon formulations to help reduce and prevent hypoglycaemia.

Metreleptin Treatment in a Boy with Congenital Generalized Lipodystrophy due to Homozygous c.465_468delGACT (p.T156Rfs*8) Mutation in the BSCL2 Gene: Results From the First-year

Congenital generalized lipodystrophy (CGL) is a rare, autosomal recessive disorder characterized by an almost complete absence of body fat. In CGL, patients may have hyperphagia due to leptin deficiency. Recombinant human leptin (metreleptin) has been suggested as an effective treatment option. We present successful treatment with metreleptin in a boy with CGL and results from the first year of follow-up. An eight-month-old boy presented with excessive hair growth and a muscular appearance. On examination he had hypertrichosis, decreased subcutaneous adipose tissue over the whole body and hepatomegaly. Laboratory investigations revealed hypertriglyceridemia, hyperinsulinemia, elevated liver transaminases and low leptin levels. Molecular genetic analysis detected a homozygous, c.465_468delGACT (p.T156Rfs*8) mutation in the BSCL2 gene. A diagnosis of CGL type 2 was considered. Despite dietary intervention, exercise, and treatment with additional omega-3 and metformin, the hypertriglyceridemia, hyperinsulinemia, and elevated liver transaminase levels worsened. Metreleptin treatment was started and after one year hyperphagia had disappeared, and there was dramatic improvement in levels of insulin, hemoglobin A1c, triglycerides and liver transaminases. Hepatosteatosis was lessened and hepatosplenomegaly was much improved. Metreleptin appears to be an effective treatment option in children with CGL that remarkably improved metabolic complications in the presented case. Initiation of metreleptin treatment in the early period may decrease mortality and morbidity, and increase the quality of life in children with CGL.

Assessment of gonadotrophin suppression in girls treated with GnRH analogue for central precocious puberty; validity of single luteinizing hormone measurement after leuprolide acetate injection.

OBJECTIVE: Intravenous GnRH stimulation test has often been used as gold standard test for the evaluation of hypothalamic-pituitary-gonadal axis in the diagnosis of central precocious puberty (CPP) and in the assessment of pubertal suppression. However, this test is time-consuming, costly and uncomfortable for the patients. We aimed to analyse the validity of single LH sample 90 min after GnRH analogue (GnRHa) administration in the evaluation of gonadotrophin suppression during CPP therapy and to determine a cut-off level for LH indicating adequate suppression. DESIGN: Prospective study. PATIENTS AND METHODS: One hundred and forty-two patients with CPP were included in this study. Peak LH level during iv GnRH stimulation test after the third dose of GnRHa was compared with LH level 90 min after injection of the 3rd dose of GnRHa. RESULTS: There was a positive correlation between LH level following a GnRHa injection and peak LH during standard iv GnRH stimulation test (r = 0·83; P < 0·0001). A LH value of 2·5 mIU/ml or less 90 min after GnRHa injection was considered to be the cut-off for the determination of pubertal suppression (sensitivity and specificity was 100% and 88%, respectively). In 117 patients, gonadotrophin suppression was existed according to both GnRHa and iv GnRH tests. In 25 patients, gonadotrophin suppression was not found in the GnRHa test. However, 16 of them were suppressed according to the iv GnRH test. CONCLUSION: Single LH determination 90 min after GnRHa administration using a cut-off level of 2·5 mIU/ml reflects pubertal suppression with a high sensitivity and specificity. However, this test may fail to show pubertal suppression in some cases. Those patients who appear to be inadequately suppressed should be reassessed using standard iv GnRH stimulation test for optimal dose adjustment.

Evaluation of serum kisspeptin levels in girls in the diagnosis of central precocious puberty and in the assessment of pubertal suppression.

BACKGROUND: Onset of puberty is dependent on pulsatile secretion of gonadotropin releasing hormone (GnRH). The kisspeptin-GPR54 signaling system has a considerable role in GnRH physiology and induction of puberty. OBJECTIVES: To evaluate kisspeptin levels in girls with central precocious puberty (CPP) at the time of the diagnosis and during follow-up, to determine whether or not kisspeptin may serve as a marker for diagnosis and follow-up of CPP. PATIENTS AND METHODS: Kisspeptin levels of 28 girls with CPP were measured at the time of diagnosis and repeated at the 6th month of therapy after complete pubertal suppression and compared to kisspeptin levels of 13 age-matched prepubertal controls. RESULTS: Kisspeptin levels of girls with CPP (10.2 +/- 2.6 pg/mL) were higher than those in controls (8.6 +/- 1.5 pg/mL (p = 0.019). There was a significant decline in the kisspeptin levels (7.3 +/- 1.3 pg/mL) of girls with CPP after pubertal suppression (p < 0.0001). CONCLUSION: These findings suggest that kisspeptin levels can be used as corroborative evidence for diagnosis of CPP and a valuable parameter for monitoring treatment efficacy.

17beta-hydroxysteroid dehydrogenase type 3 deficiency as a result of a homozygous 7 base pair deletion in 17betaHSD3 gene.

17-beta-Hydroxysteroid dehydrogenase type 3 (17betaHSD-3) converts delta4 androstenedione (A) to testosterone (T) in the testes. This enzyme plays a key role in androgen synthesis and it is essential for normal fetal development of male genitalia. 17betaHSD-3 deficiency is a rare cause of 46,XY disorders of sexual development. Here, we report a 16-year-old 46,XY patient with 17betaHSD-3 deficiency raised as a female and significantly virilized in puberty. A homozygous 7 base pair deletion on exon 10 was determined in HSD17B3 gene (c.777-783del_GATAACC). Our patient had one of the very rare mutations, which was previously unencountered in Turkish patients with 17betaHSD type 3, and she is the second reported case with this deletion.

Vitamin D-deficient rickets mimicking ankylosing spondylitis in an adolescent girl.

Vitamin D-deficient rickets (VDDR) remains an important health problem especially in developing countries. Insufficient dietary intake of vitamin D and inadequate sun exposure increase the risk of vitamin D deficiency. Since their vitamin D requirement is increased, children and adolescents are potentially at higher risk for vitamin D deficiency. In adolescents, vitamin D deficiency causes osteomalacia, osteoporosis and muscle weakness. While osteoporosis is not associated with bone pain, osteomalacia has been associated with isolated or generalized bone pain. The present case suffered from generalized bone pain for three years. She was misdiagnosed as ankylosing spondylitis, which is a seronegative arthropathy, and was treated with corticosteroids and methotrexate, which have potential side effects. Hypocalcemia, hypophosphatemia, elevated alkaline phosphatase level, secondary hyperparathyroidism, and extremely low vitamin D level were consistent with the diagnosis of severe vitamin D deficiency. Complete clinical and biochemical resolution was achieved with vitamin D replacement.

Long-term follow-up of transient neonatal diabetes mellitus due to a novel homozygous c.7734C>T (p.R228C) mutation in ZFP57 gene: relapse at prepubertal age.

OBJECTIVES: Neonatal diabetes mellitus (NDM) is a rare form of monogenic diabetes present within the first six months of life. NDM can be transient (TNdM) or permanent (PNDM). About 70% of TNDM cases have abnormalities in the imprinted region of chromosome 6q24. In TNDM, diabetes remits at infancy whilst may relapse later in life. Chromosome 6q24 related TNDM usually relapses at the pubertal period, while in some cases, relapse occurs earlier. It has been reported that these cases can respond to sulfonylurea treatment, while more evidence and experience are needed. CASE PRESENTATION: Herein, we reported relapse of diabetes at prepubertal age and its response to sulphonylurea therapy in a case with TNDM due to a homozygous c.7734C>T (p.R228C) variant in the ZFP57 gene. CONCLUSIONS: A response to the sulphonylurea monotherapy seems not optimal for relapsed TNDM due to chromosome 6q24 abnormalities.