A Boy with 46,XX Karyotype (SRY double-positive) having a Leydig Cell Tumor.

Leydig cell tumors are the most common type of testicular sex cord stromal tumors. Presence of Y chromosome is associated with tumor risk in sex development disorder (DSD), however tumor development without Y chromosome are extremely rare. A 16-year-old boy diagnosed with Leydig cell tumor due to a mass in the right testis was referred after the right orchiectomy. In physical examination, left testis was 10 ml, and a labium residue in penoscrotal region with bilateral gynecomastia was present. Karyotype was 46,XX, and SRY was double-positive in FISH analysis. Ifosfamide, carboplatin and etoposide chemotherapy was initiated due to Leydig cell tumor. Here, we report the first pediatric case having 46,XX, SRY double-positive testicular DSD with Leydig cell tumor.

Basal Serum Neurokinin B Levels in Differentiating Idiopathic Central Precocious Puberty from Premature Thelarche.

OBJECTIVE: To find out the diagnostic role of kisspeptin and neurokinin B in idiopathic central precocious puberty (ICPP) and premature thelarche (PT). METHODS: The girls who presented with early breast development before the age of 8 years were evaluated. Patients with intracranial pathologies were excluded. Basal and stimulated follicle-stimulating hormone/luteinizing hormone (LH) levels and basal neurokinin B/kisspeptin levels were measured. Patients who had peak value of LH >5 mIU/mL and a bone age (BA)/chronological age (CA) ratio >1.1 were diagnosed as central precocious puberty (CPP), while cases who did not meet these criteria were diagnosed as PT. Healthy age-matched prepubertal girls were included as the control group. RESULTS: The study group contained 25 girls with ICPP (7±0.8 years), 35 girls with PT (6.8±0.7 years), and 30 controls (6.7±0.7 years). Basal serum kisspeptin and neurokinin B levels were 2.36±0.47 ng/mL and 2.61±0.32 ng/mL, respectively in the ICPP group, 2.23±0.43 ng/mL and 2.24±0.23 ng/mL, respectively in the PT group, and 1.92±0.33 ng/mL and 2.03±0.24 ng/mL, respectively in the controls. Both kisspeptin and neurokinin B levels were higher in the ICPP and PT groups compared to controls (p<0.05). Moreover, basal neurokinin B level was different between ICPP and PT groups (p<0.01). A serum neurokinin B level of 2.42 ng/mL provided the most appropriate level to differentiate ICPP from PT, with a sensitivity of 84% and specificity of 77.1%. CONCLUSION: Differentiation of CPP from PT is sometime difficult, and there is a need for a simple method for the differential diagnosis. Our results suggest that basal serum neurokinin B level can be used as an adjunctive parameter to differentiate ICCP from PT.

A Novel Null Mutation in P450 Aromatase Gene (CYP19A1) Associated with Development of Hypoplastic Ovaries in Humans.

OBJECTIVE: The CYP19A1 gene product aromatase is responsible for estrogen synthesis and androgen/estrogen equilibrium in many tissues, particularly in the placenta and gonads. Aromatase deficiency can cause various clinical phenotypes resulting from excessive androgen accumulation and insufficient estrogen synthesis during the pre- and postnatal periods. In this study, our aim was to determine the clinical characteristics and CYP19A1 mutations in three patients from a large Turkish pedigree. METHODS: The cases were the newborns referred to our clinic for clitoromegaly and labial fusion. Virilizing signs such as severe acne formation, voice deepening, and clitoromegaly were noted in the mothers during pregnancy. Preliminary diagnosis was aromatase deficiency. Therefore, direct DNA sequencing of CYP19A1 was performed in samples from parents (n=5) and patients (n=3). RESULTS: In all patients, a novel homozygous insertion mutation in the fifth exon (568insC) was found to cause a frameshift in the open reading frame and to truncate the protein prior to the heme-binding region which is crucial for enzymatic activity. The parents were found to be heterozygous for this mutation. Additionally, all patients had hypoplastic ovaries instead of cystic and enlarged ovaries. CONCLUSION: A novel 568C insertion mutation in CYP19A1 can lead to severe aromatase deficiency. Homozygosity for this mutation is associated with the development of hypoplastic ovaries. This finding provides an important genetic marker for understanding the physiological function of aromatase in fetal ovarian development.

A successful unrelated peripheral blood stem cell transplantation with reduced intensity-conditioning regimen in a patient with late-onset purine nucleoside phosphorylase deficiency.

PNP deficiency is a rare combined immunodeficiency with autosomal recessive mode of inheritance. The immunodeficiency is progressive with normal immune functions at birth, but then, T-cell deficiency with variable B-cell functions usually presents by the age of two yr. The only curative treatment for PNP deficiency is hematopoietic stem cell transplantation. Here, we present a 13-yr-old girl with late-onset PNP deficiency. Despite many complications of infections, she was successfully transplanted with a reduced intensity-conditioning regimen from an HLA-identical unrelated donor.

Wolcott-Rallison syndrome due to a novel mutation (R491X) in EIF2AK3 gene.

Wolcott-Rallison syndrome (WRS) is a rare autosomal recessive disorder characterized by early-onset diabetes, spondyloepiphyseal dysplasia, tendency to skeletal fractures secondary to osteopenia, and growth retardation. Mutations in the eukaryotic translation initiation factor 2α kinase (EIF2AK3) gene are responsible for this disorder. Here, we describe a boy with neonatal diabetes, diagnosed at 2 months of age, who developed severe growth retardation and a skeletal fracture during the follow-up period. The patient's skeletal X-ray revealed findings of skeletal dysplasia. A clinical diagnosis of WRS was confirmed by the identification of a novel homozygous nonsense mutation (R491X) in exon 9 of the EIF2AK3 gene. The aim of this report is to raise the awareness for Wolcott-Rallison syndrome in cases presenting with isolated neonatal diabetes. This patient demonstrates that the other findings of this syndrome might be obscured by a diagnosis of isolated neonatal diabetes.

Analysis of TPO gene in Turkish children with iodide organification defect: identification of a novel mutation.

The objective was to determine molecular genetic analysis of the TPO gene in Turkish children with iodide organification defect (IOD). Patients with a diagnosis of primary hypothyroidism were evaluated. Subjects having a definite diagnosis of autoimmune thyroiditis, thyroid gland dysplasia and, or iodine deficiency were excluded. A total of 10 patients from nine unrelated Turkish families, with an unknown etiology of hypothyroidism, and with a presumptive diagnosis of IOD were included in the study. A perchlorate discharge test (PDT) was performed to all subjects, and sequence analysis of TPO gene was applied in patients with a positive PDT. Five out of 10 patients have a total IOD, while the five remaining patients have a partial IOD according to PDT results. In two sisters, one has a partial and the other one has a total IOD a novel homozygous nonsense p.Q315X mutation was found in exon 8. Additionally, a previously known homozygous missense p.R314W mutation was detected in the same exon in another patient with a total IOD. No TPO gene mutation was detected in any of the seven remaining patients. Two different TPO gene mutations were found to be responsible for IOD in two unrelated Turkish families from the same ethnic background. More subjects should be screened for detecting the prevalence and spectrum profile of TPO mutations in our population that might be helpful for understanding the pathophysiology of congenital hypothyroidism.

Permanent neonatal diabetes mellitus caused by a novel homozygous (T168A) glucokinase (GCK) mutation: initial response to oral sulphonylurea therapy.

OBJECTIVE: To evaluate the clinical response to sulphonylurea treatment in a child with a homozygous T168A GCK (glucokinase) mutation, causing permanent neonatal diabetes mellitus (PNDM). STUDY DESIGN: Oral glibenclamide was given for 3 months. Pancreatic beta cell function was assessed by a glucagon stimulation test. Mutant and wild-type (WT) GCK were characterized. RESULTS: Sulphonylurea treatment resulted in a 12-fold increase in basal and stimulated C-peptide levels. HbA1c levels were reduced from 9.4% to 8.1% on a reduced insulin dose (0.85 to 0.60 U/kg/day). Mutant T168A-GST-GCK showed reduced kinetic activity (0.02 fold) compared to WT. CONCLUSIONS: Sulphonylureas can close the adenosine triphosphate (ATP)-sensitive potassium channel and elicit insulin secretion, but the ATP generated from metabolism is insufficient to fully restore insulin secretory capacity. Nonetheless, sulphonylurea treatment should be tried in patients with GCK-PNDM, particularly those with mutations resulting in less severe kinetic defects, in whom improved glycemic control may be obtained with lower doses of insulin.

Bone metabolism markers and bone mineral density in children with neurofibromatosis type-1.

Some experimental studies suggested that there may be a bone formation defect rather than a disorder in bone resorption in patients NF1. The aim of this study was to determine bone mineral density (BMD) with dual-energy X-ray absorptiometry (DEXA) and investigate specific bone formation and bone resorption and bone turnover markers in children with NF1. Thirty-two children and adolescents (16 boys, 16 girls; 16 prepubertal, 16 pubertal) with NF1 were recruited. Their age ranged from 3 to 17 years. They were compared with matched healthy children. Dual-energy X-ray absorptiometry were applied to 26 patients and 27 controls. Nine of 32 subjects with NF1 had a skeletal abnormality. BMD of the lumbar spine, and femoral neck in NF1 patients significantly decreased compared to that of healthy subjects. They were also significantly decreased in pubertal patients when compared to pubertal controls and in prepubertal patients when compared to prepubertal controls. Patients with skeletal abnormalities were found to have significantly lower level of osteocalcin when compared to patients without skeletal abnormality. Other biochemical markers did not exhibit any difference between the groups. In conclusion, our findings suggest that bone formation markers rather than DEXA could be good predictors of skeletal abnormalities among NF1 patients. However, in our study the number of the NF1 patients with skeletal abnormality and the number of bone formation markers studied were all limited. It is appropriate to perform larger studies with other bone formation markers beside osteocalcin.

A family with a novel TSH receptor activating germline mutation (p.Ala485Val).

Autosomal dominant nonautoimmune hyperthyroidism (ADNAH) is caused by gain of function mutations in the TSH receptor (TSHr) gene and characterized by toxic thyroid hyperplasia with a variable age of onset in the absence of thyroid antibodies and clinical symptoms of autoimmune thyroid disease in at least two generations. We report here a Turkish family with a novel TSHr gene mutation with distinct features all consistent with ADNAH. Thyroid function tests of the proband were as follows: free T3: 13.1 pg/ml (N: 1.8-4.6); free T4: 5.1 ng/dl (N: 0.9-1.7); TSH: 0.01 microIU/ml (N: 0.2-4.2); and TSH receptor antibody: 2 IU/ml (N: 0-10). A heterozygous missense mutation in exon 10 of the TSHr gene (c.1454C>T) resulting in the substitution of valine for alanine at codon 485 (p.Ala485Val) was found in the father and his son and daughter. This mutation had arisen de novo in the father. Functional studies of the novel TSHr germline mutation demonstrated a higher constitutive activation of adenyl cyclase than wild type without any effect on phospholipase C activity. In conclusion, our data indicate that gain of function germline mutations in the TSHr gene should be investigated in families with members suffering from thyrotoxicosis and progressive growth of goiter, but without clinical and biochemical evidence of autoimmune thyroid disease. In addition, patients harboring the same mutation of the TSHr gene may show wide phenotypic variability with respect to the age at onset, and severity of hyperthyroidism and thyroid growth.