Low Birth Weight is Associated with More Severe Course of Steroid-Sensitive Nephrotic Syndrome in Children, Multicentric Study.

BACKGROUND: Several previous studies have reported a more severe course of nephrotic syndrome in children with low birth weight. PATIENTS: Cohort of 223 children with idiopathic nephrotic syndrome. METHODS: We aimed to investigate the association between course of nephrotic syndrome and low birth weight. Data from seven paediatric nephrology centres were used. RESULTS: Children with low birth weight had 3.84 times higher odds for a more severe course of steroid-sensitive nephrotic syndrome (95% CI 1.20-17.22, P=0.041), and those with low birth weight and remission after 7 days had much higher odds for a more severe course of disease (OR 8.7). Low birth weight children had a longer time to remission (median 12 vs. 10 days, P=0.03). They had a higher need for steroid-sparing agents (OR for the same sex=3.26 [95% CI 1.17-11.62, P=0.039]), and the odds were even higher in females with low birth weight (OR 6.81). There was no evidence of an association either between low birth weight and focal segmental glomerulosclerosis or between low birth weight and steroid-resistant nephrotic syndrome. DISCUSSION: We conducted the first multicentric study confirming the worse outcomes of children with NS and LBW and we found additional risk factors. CONCLUSIONS: Low birth weight is associated with a more severe course of steroid-sensitive nephrotic syndrome, while being female and achieving remission after 7 days are additional risk factors.

The Development and Neurophysiological Assessment of Newborn Auditory Cognition: A Review of Findings and Their Application.

This review article introduces the basic principles of infants' neurophysiology, while summarizing the core knowledge of the anatomical structure of the auditory pathway, and presents previous findings on newborns' neural speech processing and suggests their possible applications for clinical practice. In order to tap into the functioning of the auditory pathway in newborns, recent approaches have employed electrophysiological techniques that measure electrical activity of the brain. The neural processing of an incoming auditory stimulus is objectively reflected by means of auditory event-related potentials. The newborn's nervous system processes the incoming sound, and the associated electrical activity of the brain is measured and extracted as components characterized by amplitude, latency, and polarity. Based on the parameters of event-related potentials, it is possible to assess the maturity of a child's brain, or to identify a pathology that needs to be treated or mitigated. For instance, in children with a cochlear implant, auditory event-related potentials are employed to evaluate an outcome of the implantation procedure and to monitor the development of hearing. Event-related potentials turn out to be an irreplaceable part of neurodevelopmental care for high-risk children e.g., preterm babies, children with learning disabilities, autism and many other risk factors.

Severe vitamin D deficiency in preterm infants: possibly no association with clinical outcomes?

PURPOSE: The primary objective of this study was to compare clinical outcomes of very low birth weight (VLBW) infants with 25-hydroxy vitamin D [25(OH)D] levels <25 nmol/l in umbilical cord blood versus VLBW infants with 25(OH)D levels in cord blood >25 nmol/l. The secondary objective was to evaluate umbilical cord vitamin D as a risk factor for respiratory distress syndrome (RDS) in preterm infants. METHODS: We examined 25(OH)D levels in umbilical cord blood and in infants' serum at discharge from the neonatal intensive care unit. We evaluated the associations between severe vitamin D deficiency and various laboratory findings and clinical outcomes. RESULTS: Eighty one infants with birth weight less than 1500 g met the entry criteria for this study and were divided to groups according to umbilical cord blood vitamin D [Group A: 25(OH)D < 25 nmol/l; 10 ng/ml and Group B: 25(OH)D > 25 nmol/l; 10 ng/ml]. Overall, 81.5% of the infants had a 25(OH)D level <50 nmol/L and 44.4% had a level <25 nmol/L. The laboratory findings and the subsequent clinical outcomes were comparable in infants in both groups (non-significant difference). Only the infants in the 25(OH)D 25 nmol/L group had a lower calcium in urine at age 28 d (p=.0272). In addition, we found in this study that umbilical cord vitamin D level does not lead to a higher or lower risk of RDS (odds ratio 1.044; 95% confidence interval 0.349-0.88; p=.0771). CONCLUSIONS: In our prospective cohort study, we found no significant association between vitamin D status and selected clinical outcomes when using a cut-off of 25 nmol/l (severe vitamin D deficiency) in preterm infants.

Oral Ibandronate Therapy in Three Patients with Osteogenesis Imperfecta.

INTRODUCTION: Treatment with orally administered ibandronate is an effective way to increase bone mineral density (BMD) and reduce fracture rate in post-menopausal women and in men with osteoporosis. There are only very few reports concerning ibandronate therapy in children and adolescents, and in patients with osteogenesis imperfecta (OI), as bisphosphonates are not registered for therapeutic use in pediatrics. CASE REPORT: We present three patients with OI, where once-monthly oral ibandronate increased spinal BMD after two and four years, respectively, of therapy without any occurrence of new fractures and no adverse reactions. Somatic growth was not affected by the ibandronate treatment. CONCLUSION: Once-monthly oral ibandronate increased BMD and most probably improved bone quality in young patients with OI.

Tubuloglomerular Disease With Cone-Shaped Epiphyses Associated With Hypomorphic Variant and a Novel p.Cys14Arg in the TTC21B Gene: A Case Report.

Monogenic nephrotic syndrome (NS) is associated with a resistance to initial glucocorticoid therapy and causative variants, which may be found in several genes influencing podocyte stability and kidney development. The TTC21B gene, which encodes the retrograde intraflagellar transport protein IFT139, is found mostly in association with ciliopathies in humans. The role of this protein in podocyte cytoskeleton stability was confirmed later and the mutated TTC21B also may be associated with proteinuric diseases, such as nephrotic syndrome. Our patient manifested as an infant with brachydactyly, nephrotic-range proteinuria, and renal tubular acidosis, and a kidney biopsy revealed focal segmental glomerulosclerosis (FSGS). Multiple phalangeal cone-shaped epiphyses of the hand were seen on X-ray. Next-generation sequencing revealed the well-described p.Pro209Leu heterozygous variant and a novel heterozygous p.Cys14Arg variant in the TTC21B gene. Our finding confirmed that the causative variants in the TTC21B gene may contribute to a spectrum of clinical features, such as glomerular proteinuric disease with tubulointerstitial involvement and skeletal abnormalities.

Newborns' neural processing of native vowels reveals directional asymmetries.

Prenatal learning of speech rhythm and melody is well documented. Much less is known about the earliest acquisition of segmental speech categories. We tested whether newborn infants perceive native vowels, but not nonspeech sounds, through some existing (proto-)categories, and whether they do so more robustly for some vowels than for others. Sensory event-related potentials (ERP), and mismatch responses (MMR), were obtained from 104 neonates acquiring Czech. The ERPs elicited by vowels were larger than the ERPs to nonspeech sounds, and reflected the differences between the individual vowel categories. The MMRs to changes in vowels but not in nonspeech sounds revealed left-lateralized asymmetrical processing patterns: a change from a focal [a] to a nonfocal [ɛ], and the change from short [ɛ] to long [ɛ:] elicited more negative MMR responses than reverse changes. Contrary to predictions, we did not find evidence of a developmental advantage for vowel length contrasts (supposedly most readily available in utero) over vowel quality contrasts (supposedly less salient in utero). An explanation for these asymmetries in terms of differential degree of prior phonetic warping of speech sounds is proposed. Future studies with newborns with different language backgrounds should test whether the prenatal learning scenario proposed here is plausible.

Duodenal Pressure Necrosis in a Child Caused by a Migrated Percutaneous Endoscopic Gastrostomy.

A two-year-old girl with two weeks of abdominal pain, vomiting, and food refusal, ten months after percutaneous endoscopic gastrostomy insertion because of inadequate peroral intake, was admitted to a tertiary centre hospital. On admission, the extracorporeal part of the gastrostomy was much shortened. X-ray examination revealed migration of the end of the gastrostomy tube with a left-shifted course of the tube through the duodenum. Gastroscopy and subsequently laparotomy were performed. A longitudinal pressure necrosis was identified under the tube, with two perforations in the duodenojejunal region. Ten centimeters of that duodenojejunal region were resected, and end-to-end anastomosis was made. The migration of the gastrostomy was probably caused by insufficient care by the parents. Pathophysiologically, the tube caused the pressure necrosis in the duodenojejunal area; this was supported by histology. This is a hitherto undescribed complication of a percutaneous endoscopic gastrostomy, showing that migration of the gastrostomy to the deeper part of the small bowel can lead to pressure necrosis, a potentially life-threatening condition in children which cannot be treated without invasive procedures.

Vitamin D status of very low birth weight infants at birth and the effects of generally recommended supplementation on their vitamin D levels at discharge.

Purpose: To evaluate vitamin D status in mothers and their very low birth weight infants (VLBW) at birth (umbilical cord blood) and at discharge with currently recommended supplementation of vitamin D.Methods: Ninety-four infants with birth weight less than 1500 g completed the study. The total daily vitamin D intake was 800-1000 IU. We examined 25-hydroxyvitamin-D [25(OH)D] levels in maternal serum before labor, in cord blood, and in infants' serum at discharge.Results: Median (IQR) serum 25(OH)D was 21 (14-36) nmol/l [8 (6-15) ng/ml] in cord blood, and 46 (37-60) nmol/l [18 (15-24) ng/ml] at discharge. Serum 25(OH)D was <50 nmol/L in 71.3% of mothers, in 91.5% of cord blood samples, and in almost 60% of preterm newborns at discharge (after 8 weeks of supplementation). Serum 25(OH)D was <75 nmol/L in 88.3% of mothers, in 97.9% of cord blood samples, and in 91.4% of preterm newborns at discharge.Conclusions: In our cohort, we found that due to the very high prevalence of 25(OH)D deficiency among mothers, the current generally recommended dose of vitamin D (800-1000 IU per day) for VLBW infants was unable to improve vitamin D levels above the desired 50 or even 75 nmol/L before discharge.

Parathyroid hormone - reference values and association with other bone metabolism markers in very low birth weight infants - pilot study.

Purpose: The aim of this pilot study was to estimate physiological parathyroid hormone (PTH) levels and their relationship with bone metabolism parameters in otherwise healthy preterm newborns with birth weight 1000-1500 g. Methods: PTH, 25(OH)D, S-Ca, S-P, and ALP were analysed from blood samples obtained from 20 preterm infants once a week up to the 36th gestational week. Results: Of the total 134 examined serum samples for PTH levels, the estimated range was 1.6-9.3 pmol/l (15.1-87.7 pg/ml). No statistically significant correlation of PTH level with that of S-Ca, S-P, or ALP was observed, except for the 56th day of life (p = .03; Rho = 0.76; n = 8). From the second month of life, there was a statistically significant relationship only between PTH and 25(OH)D (Rho = -0.71, p ≤ .0001). In our cohort, vitamin D deficiency (20 ng/ml) occurred in 75% at birth and at 30% in the 36th gestational week. Conclusions: The physiological range indicated by the measurements was close to the reference limits for adults (1-7 pmol/l; 9.4-66 pg/ml). PTH level above this range can be considered as hyperparathyroidism in preterm neonates.

Transient hyperphosphatasemia in a child with nephrolithiasis and severe prematurity / Hiperfosfatasemia transitoria en un niño con nefrolitiasis y antecedentes de prematuridad severa

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Transient hyperphosphatemia: a benign laboratory disorder in a boy with Gitelman syndrome.

Transient hyperphosphatasemia of infancy and early childhood (THI) is characterized by transiently increased activity of serum alkaline phosphatase (S-ALP), predominantly its bone or liver isoform, in children under five years of age. There are no signs of metabolic bone disease or hepatopathy corresponding with the increased S-ALP. THI is benign disorder, rather laboratory than clinical disorder, which is usually accidentally detected in both healthy and sick children. When encountered in a child with either chronic bone, liver or kidney disease, it might concern the physician. We present a three year old boy with genetically confirmed Gitelman syndrome where THI was detected accidentally during periodic check-up. S-ALP peaked to 41.8 µkat/L, there were neither laboratory or clinical signs of liver or bone disease; the S-ALP dropped to normal value of 4 µkat/L 60 days later. Therefore, the patient fulfilled the criteria for THI. There were no further increases in S-ALP.

Resumo A hiperfosfatasemia transitória benigna da infância (HTBI) é caracterizada por elevação transitória da atividade da fosfatase alcalina sérica (S-ALP), predominantemente em sua isoforma óssea ou hepática, em crianças com menos de cinco anos de idade. Não há sinais de patologia óssea metabólica ou hepatopatia correspondentes ao aumento da S-ALP. A HTBI é um distúrbio benigno, mais laboratorial que clínico, normalmente detectado acidentalmente em crianças saudáveis e acometidas por alguma patologia. Quando encontrada em crianças com doença crônica óssea, hepática ou renal, maiores preocupações são justificadas. O presente relato descreve o caso de um menino de três anos de idade com síndrome de Gitelman geneticamente confirmada, em que a HTBI foi detectada acidentalmente durante um exame periódico. A S-ALP atingiu o pico de 41,8 µkat/L, sem sinais laboratoriais ou clínicos de doença hepática ou óssea. O valor de S-ALP caiu para o nível normal de 4 µkat/L 60 dias mais tarde. Portanto, o paciente satisfazia os critérios para HTBI. Não houve outros aumentos na S-ALP.

Transient hyperphosphatemia: a benign laboratory disorder in a boy with Gitelman syndrome / Hiperfosfatemia transitória: uma alteração laboratorial benigna em um menino com síndrome de Gitelman

Abstract Transient hyperphosphatasemia of infancy and early childhood (THI) is characterized by transiently increased activity of serum alkaline phosphatase (S-ALP), predominantly its bone or liver isoform, in children under five years of age. There are no signs of metabolic bone disease or hepatopathy corresponding with the increased S-ALP. THI is benign disorder, rather laboratory than clinical disorder, which is usually accidentally detected in both healthy and sick children. When encountered in a child with either chronic bone, liver or kidney disease, it might concern the physician. We present a three year old boy with genetically confirmed Gitelman syndrome where THI was detected accidentally during periodic check-up. S-ALP peaked to 41.8 µkat/L, there were neither laboratory or clinical signs of liver or bone disease; the S-ALP dropped to normal value of 4 µkat/L 60 days later. Therefore, the patient fulfilled the criteria for THI. There were no further increases in S-ALP.

Resumo A hiperfosfatasemia transitória benigna da infância (HTBI) é caracterizada por elevação transitória da atividade da fosfatase alcalina sérica (S-ALP), predominantemente em sua isoforma óssea ou hepática, em crianças com menos de cinco anos de idade. Não há sinais de patologia óssea metabólica ou hepatopatia correspondentes ao aumento da S-ALP. A HTBI é um distúrbio benigno, mais laboratorial que clínico, normalmente detectado acidentalmente em crianças saudáveis e acometidas por alguma patologia. Quando encontrada em crianças com doença crônica óssea, hepática ou renal, maiores preocupações são justificadas. O presente relato descreve o caso de um menino de três anos de idade com síndrome de Gitelman geneticamente confirmada, em que a HTBI foi detectada acidentalmente durante um exame periódico. A S-ALP atingiu o pico de 41,8 µkat/L, sem sinais laboratoriais ou clínicos de doença hepática ou óssea. O valor de S-ALP caiu para o nível normal de 4 µkat/L 60 dias mais tarde. Portanto, o paciente satisfazia os critérios para HTBI. Não houve outros aumentos na S-ALP.

Níveis séricos de homocisteína em crianças e adolescentes com comprometimento da saúde óssea / Serum homocysteine levels in children and adolescents with impaired bone health

INTRODUÇÃO: Foi documentada uma associação entre níveis séricos elevados de homocisteína (S-Hci) e baixa densidade mineral óssea (DMO) e aumento do risco de fratura em mulheres na pós-menopausa. São escassos os dados concernentes à S-Hci e à saúde óssea em crianças. OBJETIVO: Avaliar S-Hci em crianças e adolescentes com comprometimento da saúde óssea e procurar por relações com dados clínicos e laboratoriais. PACIENTES E MÉTODOS: Avaliamos os níveis de S-Hci em 37 crianças e adolescentes (22 meninos e 15 meninas; média de idade, 13,9 ± 3,5 anos) com fraturas prevalentes por trauma de baixa energia (média 3,3 ± 2,3 por paciente) e/ou baixa DMO espinhal/L1-L4 (escore Z abaixo de -2 DP; DXA Lunar GE). Também avaliamos S-ALP, CrossLaps sérico (S-Hci-CrossLaps), osteocalcina (S-OC), altura, peso corporal, índice de massa corporal (IMC) e níveis séricos de folato e vitamina B12. Por ocasião da avaliação, as crianças não estavam tomando qualquer medicação que sabidamente influenciasse o metabolismo ósseo. Os parâmetros dependentes de idade foram expressos como escores Z ± DP. RESULTADOS: O escore Z para S-Hci foi significativamente mais alto (1,3 ± 1,5; P < 0,0001) e o escore Z de para DMO/L1-L4 foi significativamente mais baixo (-1,7 ± 1,3; P < 0,0001), respectivamente, em comparação com os valores de referência. S-ALP não diferiu dos valores de referência (P = 0,88), enquanto S-CrossLaps e S-osteocalcina foram mais elevados (1,2 ± 1,8 e 0,4 ± 0,5; P = 0,0001 e P = 0,001, respectivamente). S-Hci estava inversamente correlacionada com DMO/L1-L4 (r = -0,33; P = 0,05) e S-ALP (r = -0,36; P = 0,04) não tendo relação com o número de fraturas prevalentes (r = 0,01), S-osteocalcina (r = -0,22) ou S-CrossLaps (r = 0,003). CONCLUSÃO: Esses resultados sugerem aumento na remodelação óssea e uma influência negativa da S-Hci elevada na formação óssea e na DMO em crianças e adolescentes com fraturas recorrentes.

INTRODUCTION: Association between high serum homocysteine (S-Hcy) levels and low bone mineral density (BMD) and increased fracture risk in postmenopausal women has been documented. Data concerning S-Hcy and bone health in children are scarce. OBJECTIVE: Our aim was to evaluate S-Hcy in children and adolescents with impaired bone health and look for correlations with clinical and laboratory data. PATIENTS AND METHODS: We assessed S-Hcy levels in 37 children and adolescents (22 boys and 15 girls; mean age 13.9 ± 3.5 years) with prevalent low-energy trauma fractures (mean 3.3 ± 2.3 per patient) and/or low spinal L1-L4 BMD (below -2SD Z-score; DXA Lunar GE). We also evaluated S-ALP, serum CrossLaps, osteocalcin (S-OC), body height, weight, body mass index (BMI) and serum levels of folate and vitamin B12. At the time of assessment, the children were not taking any drugs known to influence bone metabolism. The age-dependent parameters were expressed as Z-scores ± SD. RESULTS: S-Hcy Z-score was significantly higher (1.3 ± 1.5; P < 0.0001) and L1-L4 BMD Z-score was significantly lower (-1.7 ± 1.3; P < 0.0001), respectively, in comparison with reference values. S-ALP did not differ from reference values (P = 0.88), while S-CrossLaps and S-osteocalcin were higher (1.2 ± 1.8 and 0.4 ± 0.5; P = 0.0001 and P = 0.001, respectively). S-Hcy was inversely correlated to L1-L4 BMD (r = -0.33; P = 0.05) and S-ALP (r = -0.36; P = 0.04) and not related to number of prevalent fractures (r = 0.01), S-osteocalcin (r = -0.22) or S-CrossLaps (r = 0.003). CONCLUSION: These results suggest increased bone turnover and negative influence of elevated S-Hcy on bone formation and BMD in children and adolescents with recurrent fractures.

Intravenous pamidronate in the treatment of severe idiopathic infantile hypercalcemia.

Idiopathic infantile hypercalcemia (IIH) is a rare disorder caused by CYP24A1 loss-of-function mutation, resulting in impaired degradation of 1,25-dihydroxyvitamin D3. Pamidronate, an intravenously administered bisphosphonate, which is a potent inhibitor of bone resorption, has been reported only once for treatment IIH. We present a case of a previously healthy 5-month-old boy with IIH, where calcemia peaked to 5 mmol/L. Treatment with methylprednisone and furosemide had only minor effects; therefore, 2 intravenous infusions of pamidronate (0.6 mg/kg per dose) corrected the serum calcium level to 2.95 mmol/L. Furthermore, CYP24A1 homozygous mutation p.R396W (c.1186c>t) was identified in this patient, confirming the clinical diagnosis of IIH. In conclusion, IIH has a favorable outcome once properly detected and appropriately treated. Pamidronate has a beneficial effect in those patients with IIH where glucocorticoids and furosemide fail to meet the expectations.  

Gitelman syndrome as a cause of psychomotor retardation in a toddler.

INTRODUCTION: Gitelman syndrome (GS) is a very rare autosomal recessive tubulopathy due to loss-of-function or mutation in solute carrier family12, member 3 gene (SLC12A3 gene) encoding thiazide-sensitive NaCl co-transporter in the distal convoluted tubule, leading to hypokalemia, metabolic alkalosis, hypomagnesemia, hypocalciuria and low-to-normal blood pressure. Clinical signs are mostly secondary to chronic hypokalemia and include dizziness, fatigue, constipation and weakness. Patients can also present with muscle cramps, tetany, fatigue and convulsions due to severe metabolic alkalosis or hypomagnesemia. Manifestations of GS are rarely apparent before the age of five, and the syndrome is usually diagnosed during adolescence or adulthood. Here we describe a case of GS presenting in infancy with hypokalemia and psychomotor retardation. CASE REPORT: We present an 18-month-old boy who presented with psychomotor retardation and failure to thrive. Investigations revealed hypokalemia at 2.7 mmol/L, metabolic alkalosis, hypocalciuria and normal serum magnesium level. The diagnoses of Barter syndrome (BS) and Gitelman syndrome (GS) were considered. Genetic studies confirmed the diagnosis of GS and three different mutations of in SLC12A3 gene were detected. Two mutations (c.2576T>C and c.2929C>Ty) were considered as causal ones, with the patient´s parents being the heterozygous carriers. Oral potassium supplementation resulted in normalisation of the hypokalemia and psychomotor improvement. CONCLUSION: We report a rare case of psychomotor retardation occurring at an early age in genetically confirmed GS. In spite of being a rare disorder, GS has to be considered in children with developmental delay and muscle weakness. With adequate treatment, GS patients have an excellent prognosis.

Serum homocysteine levels in children and adolescents with impaired bone health.

INTRODUCTION: Association between high serum homocysteine (S-Hcy) levels and low bone mineral density (BMD) and increased fracture risk in postmenopausal women has been documented. Data concerning S-Hcy and bone health in children are scarce. OBJECTIVE: Our aim was to evaluate S-Hcy in children and adolescents with impaired bone health and look for correlations with clinical and laboratory data. PATIENTS AND METHODS: We assessed S-Hcy levels in 37 children and adolescents (22 boys and 15 girls; mean age 13.9 ± 3.5 years) with prevalent low-energy trauma fractures (mean 3.3 ± 2.3 per patient) and/or low spinal L1-L4 BMD (below -2SD Z-score; DXA Lunar GE). We also evaluated S-ALP, serum CrossLaps, osteocalcin (S-OC), body height, weight, body mass index (BMI) and serum levels of folate and vitamin B12. At the time of assessment, the children were not taking any drugs known to influence bone metabolism. The age-dependent parameters were expressed as Z-scores ± SD. RESULTS: S-Hcy Z-score was significantly higher (1.3 ± 1.5; P < 0.0001) and L1-L4 BMD Z-score was significantly lower (-1.7 ± 1.3; P < 0.0001), respectively, in comparison with reference values. S-ALP did not differ from reference values (P = 0.88), while S-CrossLaps and S-osteocalcin were higher (1.2 ± 1.8 and 0.4 ± 0.5; P = 0.0001 and P = 0.001, respectively). S-Hcy was inversely correlated to L1-L4 BMD (r = -0.33; P = 0.05) and S-ALP (r = -0.36; P = 0.04) and not related to number of prevalent fractures (r = 0.01), S-osteocalcin (r = -0.22) or S-CrossLaps (r = 0.003). CONCLUSION: These results suggest increased bone turnover and negative influence of elevated S-Hcy on bone formation and BMD in children and adolescents with recurrent fractures.