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Diagnosis and management of pediatric nephrolithiasis/nephrocalcinosis is a very complex and challenging task for every pediatrician. It is based on correct. disease history taking, which may guide to the mode of inheritance (dominant, recessive, x-linked). Ethnicity and consanguinity should also be investigated since they predispose to high prevalence of certain disorders. One should always begin with cheap and available screening tests. Herein we will review clinical, biochemical, metabolic and genetic characteristics of the inherited diseases which lead to nephrolithiasis/nephrocalcinosis, such as: idiopathic hypercalciuria, renal hypophosphatemia, renal tubular acidosis, idiopathic infantile hypercalcemia, Dent disease, familial hypomagnesemia with hypercalciuria and nephrocalcinosis, hypocitraturia, cystinuria, primary hyperoxaluria and renal hypouricemia. Modern genetic techniques such as next generation sequencing enable nowadays diagnosis of rare disease using only a blood sample, trough massive parallel resequencing of many genes. This is very helpful for anuric patients or on dialysis where blood and urine biochemistry are not informative. Genetic testing also replaces invasive liver biopsy or unpleasant acidification tests and enables prenatal or early postnatal diagnosis.

Context: Loss-of-function mutations in makorin ring finger 3 (MKRN3), an imprinted gene located on the long arm of chromosome 15, have been recognized recently as a cause of familial central precocious puberty (CPP) in humans. MKRN3 has a potential inhibitory effect on GnRH secretion., Objectives: The objective of the study was to investigate potential MKRN3 sequence variations as well as copy number and methylation abnormalities of the 15q11 locus in patients with apparently sporadic CPP., Setting and Participants: We studied 215 unrelated children (207 girls and eight boys) from three university medical centers with a diagnosis of CPP. All but two of these patients (213 cases) reported no family history of premature sexual development. First-degree relatives of patients with identified MKRN3 variants were included for genetic analysis., Main Outcome Measures: All 215 CPP patients were screened for MKRN3 mutations by automatic sequencing. Multiplex ligation-dependent probe amplification was performed in a partially overlapping cohort of 52 patients., Results: We identified five novel heterozygous mutations in MKRN3 in eight unrelated girls with CPP. Four were frame shift mutations predicted to encode truncated proteins and one was a missense mutation, which was suggested to be deleterious by in silico analysis. All patients with MKRN3 mutations had classical features of CPP with a median age of onset at 6 years. Copy number and methylation abnormalities at the 15q11 locus were not detected in the patients tested for these abnormalities. Segregation analysis was possible in five of the eight girls with MKRN3 mutations; in all cases, the mutation was inherited on the paternal allele., Conclusions: We have identified novel inherited MKRN3 defects in children with apparently sporadic CPP, supporting a fundamental role of this peptide in the suppression of the reproductive axis.

Septo-Optic Dysplasia (SOD) is a rare disorder with postulated genetic and environmental etiology. Whilst initially considered as a very rare disease (defined as incidence of approx. 1 in 50,000 births) recent data gave a reported incidence of 1 in 10,000, with equal sex distribution. The diagnosis of SOD is predominantly a clinical one, and made with the presence of two or more features of the classic triad: 1) hypopituitarism, 2) optic nerve hypoplasia, and 3) midline brain defects, typically absence or hypoplasia of the septum pellucidum and/or corpus callosum. Hypopituitarism ranges from isolated to multiple hormone deficits, with diabetes insipidus in a minority. The condition is heterogeneous and may also manifest additional brain defects. Although homozygous mutations in the homeobox gene HESX1 have been identified in SOD, these are uncommon and genetic diagnosis can be made in only <1% of patients with autosomal recessive inheritance. Autosomal dominant inheritance has also been reported. SOX2, SOX3 and OTX2 mutations have also been identified in some forms of SOD. The aetiology of SOD is uncertain but viral infections, environmental teratogens and vascular or degenerative damage have been postulated to account for its sporadic occurrence. Other factors (endogenous or exogenous) include parental age, parity, smoking, alcohol and substance abuse, antenatal bleeding, and ethnicity. Cocaine abuse during pregnancy, which is a potent vasoconstrictor has recently been identified as a potential external cause. The phenotype of SOD is highly variable; the clinical picture may include visual impairment, short stature, obesity and sleep-wake inversion. Approximately 75-80% of patients exhibit optic nerve hypoplasia, which may be the first presenting feature. Pituitary insufficiency may evolve over time, and children with possible SOD must be kept under careful endocrine follow-up. Untreated hormonal abnormalities will further jeopardize neurodevelopment of children with SOD and could also lead to life-threatening adrenal crises. The attention should be focussed on early diagnosis and treatment and education of paediatricians how to recognize this complex disorder.

In Europe Rare Disease (RD) is the one which affects less than 1/2000, in the USA 1/1250, while in Japan RD is the one that affects fewer than 1/50,000 patients. EU estimates that 5-8000 distinct rare diseases affect 6-8% of the Population. The impact of rare diseases in the health systems is impresssive: at least 3 million patients in the UK, 4 million in Germany, and between 27 and 36 million EU citizens. There is not a precise register for rare diseases in the Republic of Macedonia. Rare diseases are becoming increasingly important as possible targets of new forms of treatment, as a valuable source of a novel insight in fundamental lows of biology, and in the specific mechanisms of many diseases. Molecular methods have created a better diagnosis and oftentimes treatment. Rare diseases pose significant problem for the patients, since their problems are often not recognized by the medical community and shunned by the health insurance. The cumulative costs of diagnosis and treatment of rare diseases is significant for any society and oftentimes not acceptable for developing countries.

Background: The genetic background of idiopathic central precocious puberty (ICPP) is not well understood, and is thought to arise from the effect of multiple genes. Familial ICPP have been reported suggesting the existence of monogenic causes of ICPP. The neurokinin B (NKB) system has recently been implicated in the regulation of the human reproductive axis. In humans, NKB and its receptor are encoded by the TAC3 and TACR3 genes, respectively. Mutations in these genes have been suggested to be causative for ICPP., Methods: ICPP was defined by pubertal onset before 8 yrs of age in girls, and a pubertal LH response to GnRH testing. Twenty eight girls with ICPP were included in the study (age at diagnosis was 5.72±2.59; bone age, 6.12±2.81, height at the start of treatment, 0.90±1.48 SD). LHRH test was performed and was pubertal in all subjects (LH 20.35±32.37 mIU/ml; FSH 23.32±15.72 mIU/ml). The coding regions of TAC and TACR3 were sequenced., Results: No rare variants were detected in TAC and TACR3 in the 28 subjects with ICPP., Conclusions: We confirmed that mutations in TAC and TACR3 are not a common cause for ICPP.

Background: Congenital abnormalities of the kidney and the urinary tract are the most common cause of pediatric kidney failure. These disorders are highly heterogeneous, and the etiologic factors are poorly understood., Methods: We performed genomewide linkage analysis and whole-exome sequencing in a family with an autosomal dominant form of congenital abnormalities of the kidney or urinary tract (seven affected family members). We also performed a sequence analysis in 311 unrelated patients, as well as histologic and functional studies., Results: Linkage analysis identified five regions of the genome that were shared among all affected family members. Exome sequencing identified a single, rare, deleterious variant within these linkage intervals, a heterozygous splice-site mutation in the dual serine-threonine and tyrosine protein kinase gene (DSTYK). This variant, which resulted in aberrant splicing of messenger RNA, was present in all affected family members. Additional, independent DSTYK mutations, including nonsense and splice-site mutations, were detected in 7 of 311 unrelated patients. DSTYK is highly expressed in the maturing epithelia of all major organs, localizing to cell membranes. Knockdown in zebrafish resulted in developmental defects in multiple organs, which suggested loss of fibroblast growth factor (FGF) signaling. Consistent with this finding is the observation that DSTYK colocalizes with FGF receptors in the ureteric bud and metanephric mesenchyme. DSTYK knockdown in human embryonic kidney cells inhibited FGF-stimulated phosphorylation of extracellular-signal-regulated kinase (ERK), the principal signal downstream of receptor tyrosine kinases., Conclusions: We detected independent DSTYK mutations in 2.3% of patients with congenital abnormalities of the kidney or urinary tract, a finding that suggests that DSTYK is a major determinant of human urinary tract development, downstream of FGF signaling. (Funded by the National Institutes of Health and others.).

In humans, congenital spinal defects occur with an incidence of 0.5-1 per 1000 live births. One of the most severe syndromes with such defects is spondylocostal dysostosis (SCD). Over the past decade, the genetic basis of several forms of autosomal recessive SCD cases has been solved with the identification of four causative genes (DLL3, MESP2, LFNG and HES7). Autosomal dominant forms of SCD have also been reported, but to date no genetic etiology has been described for these. Here, we have used exome capture and next-generation sequencing to identify a stoploss mutation in TBX6 that segregates with disease in two generations of one family. We show that this mutation has a deleterious effect on the transcriptional activation activity of the TBX6 protein, likely due to haploinsufficiency. In mouse, Tbx6 is essential for the patterning of the vertebral precursor tissues, somites; thus, mutation of TBX6 is likely to be causative of SCD in this family. This is the first identification of the genetic cause of an autosomal dominant form of SCD, and also demonstrates the potential of exome sequencing to identify genetic causes of dominant diseases even in small families with few affected individuals.

Objectives: To determine the genetic basis of disordered steroidogenesis in Kuwaiti siblings., Study Design: Two siblings (46,XX and 46,XY) had normal female external genitalia and severe glucocorticoid and mineralocorticoid deficiency presenting in the first month of life. Abdominal ultrasonography showed normal size adrenal glands, suggesting cholesterol side chain cleavage enzyme (P450scc) deficiency. The CYP11A1 gene encoding P450scc and the STAR gene encoding the steroidogenic acute regulatory protein (StAR) were directly sequenced from leukocyte DNA., Results: All exons and intron/exon boundaries of the CYP11A1 gene were normal; the STAR gene was homozygous for a novel 14-base deletion/frameshift in exon 4 (g.4643&#95;4656del), so that no functional protein could be produced. Both parents and an unaffected sibling were heterozygous; zygosity was confirmed with a BsmF1 restriction fragment length polymorphism., Conclusions: Unlike most patients with StAR deficiency, our patients did not have the massive adrenal hyperplasia typical of congenital lipoid adrenal hyperplasia. The distinction between StAR and P450scc deficiency may require gene sequencing., (Copyright © 2013 Mosby, Inc. All rights reserved.)

Background: Hypomethylation of the imprinting control region 1 (ICR 1) at the IGF2/H19 locus on 11p15 is linked to Silver-Russel syndrome (SRS)., Methods and Results: We tested the hypothesis that the severity of the phenotype in SRS patients is dependent on the clinical severity score (CSS) (1). Three SRS patients were clinically scored and their scores ranged between 12, 13 and 13. Two of the three SRS patients (66%) had hypomethylation of one allele., Conclusion: All three patients had high CSS. Nevertheless, only two of them had hypomethylation of one H19 allele. Interestingly, two of them had ventricular septal defects, but only one had H19 hypomethylation. All children had low birth length and weight, a classic facial phenotype, haemihypertrophy (>2.5 cm thinner left arm/leg in comparison to the right one), shorter leg, and striking thinness (BMI of >16.0). One child was operated for cryptorchidismus, and the same child had elbow contracture. Two children had scoliosis. All three children were short (-3 to 5.5 SD), and treatment with GH resulted in growth on the third percentile. Since one child had no hypomethylation and two had a lower degree of hypomethylation, the higher CSS (12, 13 and 13) was not followed by a higher degree of hypomethylation of the IGF2/H19 locus.

Obesity and overweight are a pandemic phenomenon in the modern world. Childhood and adolescent obesity often ends up in obesity in adults. The costs of obesity and its consequences are staggering for any society, crippling for countries in development. The etiology is complex, but most often idiopathic. Hormonal, syndromic and medication-induced obesity are well investigated. Genetic causes are increasingly described. Novel technologies such as whole exome sequencing identify ever more candidate genes influencing or causing obesity. All insights into the complex problem of obesity in a team approach to treatment: diet, psychology, medications and surgery. We briefly review epidemiology, etiology, consequences and treatment approaches in childhood and adolescent obesity, with special emphasis on emerging knowledge of its genetics.

We examined the burden of large, rare, copy-number variants (CNVs) in 192 individuals with renal hypodysplasia (RHD) and replicated findings in 330 RHD cases from two independent cohorts. CNV distribution was significantly skewed toward larger gene-disrupting events in RHD cases compared to 4,733 ethnicity-matched controls (p = 4.8 × 10(-11)). This excess was attributable to known and novel (i.e., not present in any database or in the literature) genomic disorders. All together, 55/522 (10.5%) RHD cases harbored 34 distinct known genomic disorders, which were detected in only 0.2% of 13,839 population controls (p = 1.2 × 10(-58)). Another 32 (6.1%) RHD cases harbored large gene-disrupting CNVs that were absent from or extremely rare in the 13,839 population controls, identifying 38 potential novel or rare genomic disorders for this trait. Deletions at the HNF1B locus and the DiGeorge/velocardiofacial locus were most frequent. However, the majority of disorders were detected in a single individual. Genomic disorders were detected in 22.5% of individuals with multiple malformations and 14.5% of individuals with isolated urinary-tract defects; 14 individuals harbored two or more diagnostic or rare CNVs. Strikingly, the majority of the known CNV disorders detected in the RHD cohort have previous associations with developmental delay or neuropsychiatric diseases. Up to 16.6% of individuals with kidney malformations had a molecular diagnosis attributable to a copy-number disorder, suggesting kidney malformations as a sentinel manifestation of pathogenic genomic imbalances. A search for pathogenic CNVs should be considered in this population for the diagnosis of their specific genomic disorders and for the evaluation of the potential for developmental delay., (Copyright © 2012 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.)

The WAGR contiguous gene deletion syndrome is a combination of Wilms tumor, aniridia, genito-urinary abnormalities, and mental retardation. An 8.5-year-old girl was initially investigated at the age of 18 months for congenital bilateral aniridia, cataracts, glaucoma and epicantus. The ultrasound (US) scan showed polycystic kidney disease. FISH study revealed deletion of the WT1 and PAX6 gene in the 11p13 WAGR region. Forty days after the first kidney US, the second US revealed a 3 cm tumor in the right kidney: a Wilms tumour, treated successfully with the Wilm's tumor protocol. The authors conclude that the identification of the deletions in the WAGR region in patients with aniridia should definitely be done. In addition, Wilms tumor can have a very rapid growth, which, per se requires frequent and careful ultrasound kidney controls. Polycystic kidneys can be part of the WAGR presentation.

Background: antenatal variant of Bartter syndrome is characterized by a history of polyhydramnios, premature birth, metabolic alkalosis, hypokalemia, polyuria and renal salt wasting. In this report we present a premature female baby with antenatal Barter syndrome who had three episodes of urinary tract infection (UTI), without evidence for congenital anomaly of the kidneys or urinary tract., Methods: antenatal Bartter syndrome was diagnosed according to the standard criteria. Ultrasound scan and voiding cystourethrography were performed to exclude congenital anomaly of the kidneys and urinary tract., Results: the baby presented with early hyperkalemia and acidosis. The typical biochemical features of the Bartter syndrome were observed in the second month. Despite appropriate treatment she had persistent hypercalciuria. The clinical course was complicated with recurrent episodes of febrile UTIs. Urinary tract system imaging did not demonstrate congenital anomalies. She finally died of severe dehydration, acidosis and renal failure., Conclusion: since no congenital anomaly of the kidneys or urinary tract was demonstrated in our patient, we believe that severe, persistent hypercalciuria is the most important risk factor for development of recurrent UTIs.

Background: craniopharyngioma is a frequent tumor in children with challenging surgical, endocrine, and visual consequences. We evaluated our experience in treating craniopharyngioma and its incidence in Macedonia., Methods: Thirteen children (9 male and 4 female) with craniopharyngioma (age 9.55 ± 3.74 years; range 2.90-15.11) who had been treated between 1989 and 2008 in Macedonia were reviewed., Results: initial signs were vision disturbances (10 children), seizures (1), growth retardation (13), and diabetes insipidus (DI) (2). All children were subjected to subtotal surgical removal. Cranial irradiation was performed in 12 of the 13 children, and intracystic bleomycin was given to one child. The patients were followed up for 6-229 months (mean ± SD: 107.00 ± 74.04 months). All children had multiple pituitary deficiencies after surgical removal of the tumor. Body mass index increased from 16.93 ± 6.34 standard deviation scores (SDS) at diagnosis to 26.33 ± 5.91 SDS (P>0.005) at the last follow-up. DI was permanent in 9 of the 13 children, and multiple pituitary deficiencies were seen in all children. Treatment with growth hormone resulted in normalization of adult height from -1.27 ± 1.52 SDS at the start of the treatment to -0.13 ± 1.39 SDS at the last followup. The final height was not significantly lower than the genetic target height (P>0.005). The permanent deficit was visual impairment: blindness in one or both eyes in 4 children, bitemporal hemianopsia in 4, and other defects in 2. Recurrence of the disease was ruled out in one child after 31 months. No mortality was observed in the observation period of 104.92 ± 76.11 months., Conclusions: the overall incidence of craniopharyngioma in the period of 1989-2008 in Macedonia was 1.43 per 1 000 000 person-years. Subtotal resection and systematic irradiation showed good life quality of survivors.

Background: Peripheral biofeedback is considered to be an efficient method for assessment and stress mitigation in children. The aim of the present study was to assess the levels of stress and stress mitigation in healthy school children (HSC), in children with cystic fibrosis (CF), general anxiety (GA) and attention-deficit-hyperactivity disorder (ADHD)., Methods: Each investigated group (HSC, CF, GA, ADHD) consisted of 30 school-aged children from both sexes. Psychological characteristics were evaluated on Eysenck Personality Questionnaire (EPQ). The lie scale was used to determine participant honesty. Four biofeedback games using a pulls detector were applied for assessment of the stress levels as well as to evaluate ability to relax., Results: EPQ found more psychopathological traits (P < 0.001) and less extroversion (P < 0.001) in children with GA and ADHD. In addition, high neurotic tendencies were found in children with CF (P < 0.01) and GA (P < 0.01). Unexpectedly, the lie scale was lower in ADHD children (P < 0.01) than in all other groups (HSC, CF, GA). The Magic blocks score was significantly different in relaxation levels between control and CF children (P < 0.05). Speed in the game Canal was significantly different in relaxation levels between healthy controls and all other groups, but no changes in pulls, as a relaxation measure, were found during the game. The CF group had much more commissions stemming from impulsivity (t= 5.71, P < 0.01), while the GA and ADHD children had more inattention omissions (P < 0.05). Strong negative correlation between age and pulls (r= 0.49, P= 0.003) and strong negative correlation between age and omissions (r=-0.86, P= 0.029) were found among all groups analyzed., Conclusions: The ability to learn stress mediation is correlated with age. All three groups of children had significantly lower relaxation levels when compared to healthy controls. Relaxation was more difficult for children with GA or ADHD, and easier for children with CF.

Hypomethylation of the imprinting control region 1 (ICR1) at the IGF2/H19 locus on 11p15 is linked to Silver-Russell syndrome (SRS) and/or hemihypertrophy. This SRS patient was born in term with weight of 3500 g (50 percentile) and length 48 cm (1 SD below the mean). He was first noticed at the age of 10 years for short stature (114.5 cm, -3.85 SD), relatively normal head circumference, a classic facial phenotype, hemihypertrophy (2.5 cm thinner left arm and leg in comparison to the right, asymmetric face), moderate clinodactyly and striking thinness (BMI of 15.3). At the age of 30, the body asymmetry ameliorated (1 cm thinner left arm and leg than the right), and BMI normalized (20.5 cm). Methylation analysis was performed by bisulphate treatment of DNA samples, radiolabelled PCR amplification, and digestion of the PCR products using restriction enzymes. The patient had normomethylation, and in addition hypopituitarism, with low levels of growth hormone (GH) (provocative testing before the start and after termination of GH treatment), thyroxin, TSH, FSH, LH and testosterone. The GH was given for six years, growth response was satisfactory and he reached an adult height of 166 cm. This is a first report of hypopituitarism in a patient with SRS without H19 hypomethylation. It seems that the lack of hypomethylation in this hypopituitary SRS patient is responsible, at least partly, for the favourable final adult height under GH treatment.

Progressive signs of ataxia in a eight year old girl with hypo-active knee and ankle jerks, prompted the analysis of the frataxin gene (FXN; 606829). The most common molecular abnormality--GAA trinucleotide repeat expansion in intron 1--was found with +300 GAA repeats (1490 bp) (normal individuals have 5 to 30 GAA repeats expansions, whereas affected individuals have from 70 to more than 1000 GAA triplets). Additionally she had unstable gait with incoordination of limb movements, impairment of position and vibratory senses, dysarthria, pes cavus, positive Babinski sign and scoliosis. At the age of fourteen the girl was referred in a comatose condition, in severe diabetic ketoacidosis. Insulin dependent diabetes mellitus was since treated with insulin preparations. Electrocardiogram showed diffuse T wave inversion with sinus bradycardia, while ultrasound revealed concentric, symmetric hypertrophy of the left ventricle leading to the diagnosis of hypertrophic cardiomyopathy. At the age of 14, she is bound to the wheelchair, unable to walk. Her brother started to show ataxia at the age of 8 years and subsequent analysis also showed hypertrophic cardiomyopathy. His mutational analysis revealed the same frataxin abnormality with +300 GAA repeats. So far, no signs of diabetes occurred. The parental DNA was not available for analysis.

Obesity is becoming a growing problem in developed and developing countries. Many studies report an increasing incidence of obesity in the last decade. The aim of our transversal epidemiological study was to evaluate the prevalence of overweight children, auxological characteristics and pubertal stage in healthy girls from first (200 girls), third (209), fifth (290) and seventh (223) grade of school. In this study 928 girls were evaluated through systematic school examinations in the ambulance of municipality of Karposh, Skopje. The Rome and Turkish nationality, as well as Serbian were present in a small percentage, while detailed analysis was performed in the Macedonian and Albanian population of girls. The initiation of puberty (stage M2 or P2 by Tanner) was present in Macedonian girls: 4.3% of children in first grade, 23% in third grade, and 51.7% in fifth grade. In Albanians, in first grade M2 is present in 2.7%, in third grade 5.2%, and in fifth grade 46.9%. Body mass index (BMI SDS) was +3.5 +/- 1.5 in 35% of Macedonian girls and only 5% of Albanian girls. The Macedonian girls were also significantly higher (p < 0.01) and more obese than the Albanian girls. The pubertal stage was also more advanced in Macedonian girls. Most of the obese children who were included in the study reported increased consumption of fast food. Although in the past years obesity was not a problem in our country, it is becoming more severe with every year.

A newborn girl was found to have a massive lymphatic truncal vascular malformation with overlying cutaneous venous anomaly associated with overgrown feet and splayed toes. These manifestations comprise the recently described CLOVE syndrome. She also had cranial asymmetry and developed generalized seizures, which were treated with anticonvulsants. Cranial CT showed encephalomalacia, widening of the ventricles and the sulci, hemimegalencephaly (predominantly white matter) and partial agenesis of corpus callosum. Review of the literature identified several other patients with CLOVE syndrome, some of whom were misdiagnosed as having Proteus syndrome, with strikingly similar manifestations. We conclude that CNS manifestations including hemimegalencephaly, dysgenesis of the corpus callosum, neuronal migration defects, and the consequent seizures, may be an rarely recognized manifestation of CLOVE syndrome., (2008 Wiley-Liss, Inc.)

The patient is a 24-year-old woman who first came for consultation at age 10 years. Based on clinical phenotype and thin-layer chromatography of urinary oligosaccharides, peripheral leukocytes were sent for beta-galactosidase assay. This testing showed a deficiency in enzyme activity, and gene mutation analysis identified a previously reported mutation p.H281Y (875C > T) and a novel mutation p.W273R (817T > C). Unlike previously reported patients, mutant enzymes in this patient's cultured skin fibroblasts did not respond to treatment with a chaperone compound, N-octyl-4-epi-beta-valienamine., ((c) 2008 Wiley-Liss, Inc.)