Stem/progenitor cells in fetuses and newborns: overview of immunohistochemical markers.

Microanatomy of the vast majority of human organs at birth is characterized by marked differences as compared to adult organs, regarding their architecture and the cell types detectable at histology. In preterm neonates, these differences are even more evident, due to the lower level of organ maturation and to ongoing cell differentiation. One of the most remarkable finding in preterm tissues is the presence of huge amounts of stem/progenitor cells in multiple organs, including kidney, brain, heart, adrenals, and lungs. In other organs, such as liver, the completely different burden of cell types in preterm infants is mainly related to the different function of the liver during gestation, mainly focused on hematopoiesis, a function that is taken by bone marrow after birth. Our preliminary studies showed that the antigens expressed by stem/progenitors differ significantly from one organ to the next. Moreover, within each developing human tissue, reactivity for different stem cell markers also changes during gestation, according with the multiple differentiation steps encountered by each progenitor during development. A better knowledge of stem/progenitor cells of preterms will allow neonatologists to boost preterm organ maturation, favoring the differentiation of the multiple cells types that characterize each organ in at term neonates.

Genetic risk for recurrent urinary tract infections in humans: a systematic review.

Urinary tract infections (UTIs) are a frequent cause of morbidity in children and adults and affect up to 10% of children; its recurrence rate is estimated at 30-40%. UTI may occur in up to 50% of all women in their lifetimes and frequently require medication. Recent advances have suggested that a deregulation of candidate genes in humans may predispose patients to recurrent UTI. The identification of a genetic component of UTI recurrences will make it possible to diagnose at-risk adults and to predict genetic recurrences in their offspring. Six out of 14 genes investigated in humans may be associated with susceptibility to recurrent UTI in humans. In particular, the HSPA1B, CXCR1 & 2, TLR2, TLR4, TGF-beta1 genes seem to be associated with an alteration of the host response to UTIs at various levels.

Renal function and volume of infants born with a very low birth-weight: a preliminary cross-sectional study.

AIM: The aim of our study was to compare the function and volumes of kidneys of very low birth-weight (VLBW) and of extremely low birth-weight (ELBW) infants at pre-school ages. PATIENTS AND METHODS: We did a revision of the neonatal records of infants born in our hospital that weighed < or =1500 g at birth. The children were divided into two groups according to their weight at birth: ELBW (<1000 g) and VLBW (1000-1500 g). At the age of 5.7 +/- 1.4 years, the children underwent clinical, laboratory and ultrasound renal assessments. RESULTS: Sixty-nine children fulfilled the requirements for the study. The rate of neonatal treatment with aminoglycosides was higher in ELBW preterms. Renal function parameters, i.e. estimated glomerular filtration rate and albuminuria, did not differ between the two groups of children. Urinary alpha1-microglobulin excretion was significantly higher and kidneys were significantly smaller in the ELBW group than in the VLBW group. CONCLUSION: No impairment or differences in renal parameters were found in pre-school children born ELBW compared with those born with VLBW, except for differences in kidney volume, renal cortical thickness and urinary alpha1-microglobulin excretion. Thus, patients born with ELBW would require a longer follow-up period.

A survey around the Italian pediatric units on current clinical practice for Sleep Disordered Breathing (SDB).

BACKGROUND: During recent years, interest on Sleep Disordered Breathing (SDB) in pediatric age has increased, due to the impact on quality of life, psycho-physical attitude and other serious morbidities if undiagnosed and untreated. METHODS: Italian Pediatric Respiratory Diseases Society (SIMRI) SDB-Working Group carried out an exploratory survey in Italy, from January to December 2016, to assess the diagnostic and therapeutic pathways, perception and relevance of SDB in Italian Hospitals. RESULTS: A questionnaire was sent to 180 Pediatric Units (PUs) distributed throughout the Italy; 102 Pediatric Units (PUs; 56.6%) answered and among them 57% dealt with SDB, and 94% recognized SDB as a major problem. Instrumental tests performed by the PUs were saturimetry (66%), nocturnal polygraphy with complete cardio-respiratory monitoring (46%) and full polysomnography (23%). In addition, hospital pediatricians reported that 54% of parents were unaware of the SDB and 84% did not know their complications. In the Northern Italy, the diagnosis was frequently performed with instrumental tools and the treatment was often surgical. In the Southern Italy the diagnosis was clinical, and the treatment was usually with drugs. CONCLUSIONS: The results of our study showed a heterogeneity in the diagnosis and treatment of SDB throughout Italy. Parents know little about SDB and their complications. The operator satisfaction was associated with the availability of tools for diagnosing SDB.

Immune tolerance with rituximab in congenital haemophilia with inhibitors: a systematic literature review based on individual patients' analysis.

Rituximab, a monoclonal antibody against the pan B-cell antigen CD20, has been successfully used in both adults and children for the management of malignant and non-malignant immune-mediated disorders including acquired haemophilia. On the basis of this positive experience, a number of investigators have recently used this agent in patients with congenital haemophilia and inhibitors refractory to first-line treatments. After a careful electronic and hand search, we have collected 29 studies that included 49 cases. A durable complete remission was obtained in 53% of the cases and no severe adverse events related to rituximab were recorded. A multivariate analysis applied to individual patients' data identified the diagnosis of a mild/moderate haemophilia and the concomitant treatment with factor VIII concentrates and immunosuppression agents as covariates associated with an increased response to rituximab. Large prospective randomized studies with an adequate follow-up are needed to confirm these preliminary findings.

Pelvi-ureteric junction obstruction and renal function after pyeloplasty: a retrospective study in 29 children.

AIM: Actually, unilateral obstruction is not indicated for surgery, especially if renal function is unaffected. This retrospective study focused on the renal function after pyeloplasty for unilateral obstruction in children. METHODS: Twenty-nine children were retrospectively reviewed. To compare the ultrasound readings in patients with different ages, the comparative-length-index (index) of each renal unit (RU) was calculated. MAG3 dynamic scintigraphy was applied to diagnose any obstructions. RESULTS: Children with left obstruction were younger than children with right obstruction, when surgery was performed. Scintigraphic scan of right RUs with obstruction operated later was a lower at diagnosis than jet of the normal contralateral. Normal scintigraphic scan at diagnosis of left RUs with obstruction operated early revealed that RU was slightly reduced after the operation. At both diagnosis and follow-up the index between obstructed RUs and normal contralateral was comparable, even if it was significantly higher in left obstructed RUs. At follow-up, however, the scintigraphic scan revealed that RUs were more reduced in patients who were treated late. CONCLUSION: Early pyeloplasty partially safeguard kidney function in children with unilateral obstruction, whose renal function was normal at birth. The reduced kidney function observed before surgery was not proportionally improved after surgery with respect to the contralateral that was not affected.

Therapeutic options in childhood nocturnal enuresis.

Monosymptomatic nocturnal enuresis, a heterogeneous condition, is frequently treated in children aged >5 years. Of the various treatment options, enuresis alarm has been widely advocated as being effective for treating nocturnal enuresis, while extracorporeal pelvic floor magnetic stimulation for overactive bladder, urge incontinence and urgency-frequency syndrome has not yet been confirmed by controlled studies as primary treatment for monosymptomatic nocturnal enuresis. Desmopressin, an antidiuretic hormone (ADH) analog, or arginine vasopressin (AVP), can resolve primary nocturnal enuresis by decreasing night-time urine production. Enuretic children requiring either desmopressin or desmopressin plus oxybutynin to achieve dryness have polyuria. Tricyclic antidepressants (i.e. imipramine) are used successfully in enuretic children. Although tricyclics and desmopressin are effective in reducing the number of wet nights, most children relapse after discontinuation of active treatment. Combined therapy (enuresis alarm, bladder training, motivational therapy and pelvic floor muscle training) is more effective than each component alone or than pharmacotherapy. Furthermore, desmopressin combined with alarm therapy has a positive effect on enuresis. Pharmacotherapy can provide early relief of enuresis, while behavioral intervention may lead to greater long-term benefits. The positive effect of achieving dry nights with pharmacotherapy can encourage the child to sustain behavioral therapy.

Nutrient oxidation during moderately intense exercise in obese prepubertal boys.

The aim of this study was to measure the nutrient oxidation rate during walking at different speeds and to identify the walking speed associated with the highest fat oxidation rate in a group of prepubertal boys with different levels of adiposity. Twenty-four prepubertal boys (age, 10 +/- 1 yr) with different levels of overweight (body mass index, 25.5 +/- 3.5 kg/m(2); sd score of body mass index, 3.4 +/- 1.1) performed a treadmill test. We measured by indirect calorimetry their respiratory exchange while they walked at speeds of 4, 5, and 6 km/h as well as their maximal oxygen uptake. The fat oxidation rate did not change significantly when the speed of walking was increased, whereas carbohydrate oxidation increased significantly (P < 0.001). A significant (P < 0.05) association was found between adiposity (percent fat mass) and the fat to carbohydrate oxidation ratio during walking at 4, 5, and 6 km/h (r = 0.37, r = 0.37, and r = 0.36, respectively), adjusting for exercise intensity (maximal oxygen uptake, percentage). The lowest fat to carbohydrate oxidation ratio, i.e. the highest fat oxidation/carbohydrate oxidation rate, was found at a walking speed of 4 km/h. Moderately intense exercise promoted the highest fat to carbohydrate oxidation ratio. Increasing the exercise intensity did not promote fat oxidation. Therefore, walking at a speed of 4 km/h is recommended as practicable exercise for obese boys and, consequently, for the treatment of childhood obesity.

Genetic analysis carried out on blood-spots of phenylalanine hydroxylase-deficient newborns detected by northeastern Italian neonatal screening.

The aim of this work was to perform genetic analysis on 18 different blood-spot samples collected from neonates detected as hyperphenylalaninemic by Northeastern Italian screening program. DNA was extracted from blood-spots. Exons/introns of PAH gene were amplified by polymerase chain reaction (PCR), and PCR products were purified and sequenced with both forward and reverse primers. The most frequent mutations were IVS12nt1g>a (16.7%) and R408W, P281L and L48S (all together 11.1%). As expected, compound heterozygosity was the usual finding; homozygosity was found only in two patients with R158Q and IVS2nt5g>c mutations. The V230I mutation was reported for the first time in Italy. We found six previously described polymorphisms (V245V, IVS4nt47c>t, IVS2nt19t>c, IVS3nt-22c>t, IVS5nt-54a>g, and E280>Q280). To our knowledge, four genotypes were not previously described: R158Q/V230I present in one patient with classical PKU; and L48S/R408Q, A403V/IVS2nt-13t>g, and G272X/V230I present in patients showing HPA phenotype. Most of the mutations were located in the exons 12 and 7 and in exon/intron 2 (83.3% detection of total mutations in PKU or HPA patients of Northeastern Italy). From a practical viewpoint, the genetic analysis of blood-spots collected on Guthrie cards for neonatal screening for PKU could be a simple method to establish the genotype of neonates. Consequently, the genotype/phenotype correlation could lead to a more accurate diagnosis and prognosis for families.

Total and exogenous carbohydrate oxidation in obese prepubertal children.

The aim was to explore whether the origin of carbohydrate oxidation (exogenous compared with endogenous carbohydrate) after consumption of a mixed meal was influenced by obesity in children. Ten obese prepubertal children 8 y of age (44.2 +/- 3.6 kg) were studied over 9.5 h and compared with eight normal-weight, matched control children (28.5 +/- 1.6 kg). They were fed a mixed meal containing naturally enriched [13C]carbohydrate (cane sugar and popcorn) providing 55% of the daily energy requirement as measured by 24-h resting metabolic rate. Total carbohydrate oxidation was calculated by indirect calorimetry (hood system) whereas exogenous carbohydrate oxidation was estimated from carbon dioxide production (VCO2), the isotopic enrichment of breath 13CO2, and the abundance of [13C]carbohydrate in the meal ingested. The time course of 13CO2 in breath-measured over 570 min-followed a similar pattern in both groups. Although total carbohydrate oxidation was not significantly different among the two groups, exogenous carbohydrate utilization was significantly greater (P < 0.03) and endogenous carbohydrate oxidation was significantly lower (P < 0.05) in obese compared with control children. In addition, the rate of exogenous carbohydrate oxidation expressed as a proportion of total carbohydrate oxidation was positively related to the body fat of the children (r = 0.68, P < 0.01). The study suggests that in the postprandial phase, a smaller proportion of carbohydrate oxidation is accounted for by glycogen breakdown in obese children. The sparing of endogenous glycogen may result from decreased glycogen turnover already present at an early age.

Whole-body protein turnover and resting energy expenditure in obese, prepubertal children.

BACKGROUND: Obesity is becoming more frequent in children; understanding the extent to which this condition affects not only carbohydrate and lipid metabolism but also protein metabolism is of paramount importance. OBJECTIVE: We evaluated the kinetics of protein metabolism in obese, prepubertal children in the static phase of obesity. DESIGN: In this cross-sectional study, 9 obese children (x +/- SE: 44+/-4 kg, 30.9+/-1.5% body fat) were compared with 8 lean (28+/-2 kg ,16.8+/-1.2% body fat), age-matched (8.5+/-0.2 y) control children. Whole-body nitrogen flux, protein synthesis, and protein breakdown were calculated postprandially over 9 h from 15N abundance in urinary ammonia by using a single oral dose of [15N]glycine; resting energy expenditure (REE) was assessed by indirect calorimetry (canopy) and body composition by multiple skinfold-thickness measurements. RESULTS: Absolute rates of protein synthesis and breakdown were significantly greater in obese children than in control children (x +/- SE: 208+/-24 compared with 137+/-14 g/d, P < 0.05, and 149+/-20 compared with 89+/-13 g/d, P < 0.05, respectively). When these variables were adjusted for fat-free mass by analysis of covariance, however, the differences between groups disappeared. There was a significant relation between protein synthesis and fat-free mass (r = 0.83, P < 0.001) as well as between protein synthesis and REE (r = 0.79, P < 0.005). CONCLUSIONS: Obesity in prepubertal children is associated with an absolute increase in whole-body protein turnover that is consistent with an absolute increase in fat-free mass, both of which contribute to explaining the greater absolute REE in obese children than in control children.

Diagnostic effectiveness of simultaneous thyroxine and thyroid-stimulating hormone screening measurements. Thirteen years' experience in the Northeast Italian Screening Programme.

OBJECTIVES: To evaluate the effectiveness of thyroid-stimulating hormone (TSH) and thyroxine (T4) measurements at neonatal screening for congenital hypothyroidism, we compared our false-negative results with those we would have obtained if we had used TSH screening alone. SUBJECTS AND METHODS: Between January 1989 and December 2001 745,258 newborns were screened (98.3% of total born) for congenital hypothyroidism in northeast Italy. T4 and TSH were measured simultaneously on blood spots collected after birth. Between 1989 and 1998, semi-quantitative total T4 (tT4) and TSH concentrations were measured by radiolabelled immunological assay and, from 1999 to 2001, using time-resolved fluorometer Delfia instruments (EG&G Wallac Oy, Finland) and fluoroimmunometric assay (Delfia neonatal hTSH and T4 kits). RESULTS: Ten neonates were missed by our screening programme (normal tT4 and TSH) and classified as false negatives; these infants were diagnosed later in life with central hypothyroidism. If we had measured TSH alone in our screening programme, we would have missed an additional 21 patients with low tT4 and normal TSH; of these, four were affected by central hypothyroidism and 17 were diagnosed within the second month of life as affected by primary hypothyroidism with delayed TSH rise. CONCLUSIONS: Simultaneous T4 and TSH measurements at neonatal screening can miss patients affected by central hypothyroidism. However, this screening procedure allows identification of cases of central hypothyroidism with low T4 values and those neonates affected by primary hypothyroidism with delayed TSH rise who we would have missed by using the TSH measure alone.

Nenatal drug induced nephrotoxicity : old and next generation biomarkers for early detection and management of neonatal drug-induced nephrotoxicity, with special emphasis on uNGAL and on metabolomics.

For a long time, nephrotoxicity has been definitively defined as renal injury or dysfunction that arises as a direct or indirect result of exposure to drugs and industrial or environmental chemicals. There are a number of inherent difficulties in diagnostic procedures for toxic nephropathy, which include the absence of standard diagnostic criteria and the inability to relate exposure to a given agent and the observed effect. Critically ill newborns represent a high risk population for developing toxic nephropathy because of incomplete maturation of the kidney; furthermore, they are often treated with a combination of various therapeutic agents, each of them potentially inducing renal tissue injury. Antibiotics, antifungals, and non-steroidal antiiflammatory drugs (NSAIDs) can induce nephrotoxic damage by several, concomitant mechanisms of action on different segments of the nephron. The most common clinical feature following a nephrotoxic effect is acute kidney injury (AKI) which, in turn, comprises a spectrum of severe tissue damages along the nephron, leading to an abrupt decline in renal function. Because early stages of toxic nephropathy are characterized by very few specific clinical signs and symptoms, there is the urgent need to investigate new biomarkers for predicting nephrotoxicity and localizing the injury to a specific nephron site, in order to reduce the risk of acute renal injury and/or acute tubular necrosis. The most promising biomarker for the early assessment of kidney injury and damage is neutrophil gelatinase-associated lipocalin (NGAL). NGAL can be easily measured in urine by an automated analytical method, allowing its clinical use in emergency likewise creatinine. Considerable expectations in terms of improvement of the management of newborns developing drug-induced nephropaties derive from the clinical application of metabolomics.

Perinatal nutrient restriction reduces nephron endowment increasing renal morbidity in adulthood: a review.

Perinatal malnutrition has been included among the causes of renal disease in adulthood. Here, we consider the relationships between early supply of specific nutrients (such as protein, fat, vitamins and electrolytes) and renal endowment. Prenatal and postnatal nutrition mismatch is also discussed. In addition, this article presents the role of nutrition of both mothers and pre-term infants on nephron endowment, with final practical considerations.

Evaluating kidney damage from vesico-ureteral reflux in children.

To review the most relevant clinical studies that evaluate kidney damage in children with primary vesico-ureteral reflux (VUR), we reviewed and compared randomized controlled trials and clinical trials from scientific literature. In these studies, vesico-ureteral reflux was diagnosed by voiding cystourethrogram and kidney damage was assessed by either DMSA scan or urography. Relative risk with 95% confidence intervals was calculated using Review Manager Software (The Cochrane Collaboration, 2000). The overall relative risk of kidney damage shown by DMSA scan and urography was statistically higher in children with vesico-ureteral reflux of various degrees than in controls (3.7 times and 2.8 times, respectively). However, in high-grade VUR, the relative risk of congenital kidney damage was 5.6 times that of controls. We conclude that severe VUR is frequently associated with early kidney damage, perhaps with prenatal onset. Progression of kidney damage may depend on the severity of VUR and untreated urinary tract infections. Prevention of congenital kidney damage from severe VUR is possible when there is early intervention, even during fetal growth.

Carbohydrate-deficient transferrin determined in blood microsamples from healthy newborns by using capillary zone electrophoresis.

OBJECTIVE: There is a paucity of studies on quantitative determination of carbohydrate-deficient transferrin (CDT) in newborns. The aim of our study was therefore to determine CDT concentrations in newborns by using capillary zone electrophoresis (CZE). MATERIAL AND METHODS: Capillary blood was collected from the heels of 28 at-term healthy newborns, simultaneously with the Guthrie card screening. Forty-seven adults were examined as controls. CZE separations were performed with a P/ACE MDQ capillary electropherograph in uncoated fused-silica capillaries using a commercial reagent kit. After iron saturation, the samples were loaded by application of 0.5 psi for 15 s, and separated under 28kV with UV detection. All relevant transferrin (Tf) glycoforms were separated within 7 min. CDT quantification (%CDT) was carried out by calculating the percentage ratio between the sum of the peak areas of CDT-related glycoforms and the sum of peak areas of all Tf glycoforms. RESULTS: In most cases, good separations of Tf glycoforms were obtained. In the newborns the %CDT was 0.51 versus 0.66 in adults (difference not statistically significant). Trisialo-Tf concentration was significantly lower in newborns (3.20) than in adults (4.11). Furthermore, pentasialo-Tf appeared to be lower in newborns (7.30) than in adults (14.00), but because complete separation of the peaks of tetrasialo- and pentasialo-Tf was not always possible, this finding could not be confirmed statistically. CONCLUSIONS: CZE showed definite advantages in terms of volume of blood to be collected, simplicity and standardization of analysis and, because of the direct detection of the separated zones, accuracy of quantification. The present study provides the basic information in the search for glycosylation defects in newborns.

Therapeutic approach in a case of Pearson's syndrome.

Mitochondrial cytopathy is a multisystemic disease that requires different pharmacological and specialist approaches; although most therapies are usually of scarce effectiveness. We describe a clinical management of a very young girl with Pearson's syndrome that developed the symptoms of Kearns-Sayre syndrome. Many of symptoms were temporarily improved by the replacement therapy with hydrocortisone introduced to treat the partial adrenal insufficiency. During her life, she showed an ample clinical spectrum of symptoms because of multiple organs involvements: firstly bone marrow and, thereafter, brain, retina, inner ear, and kidney. Partial adrenal insufficiency, rarely described in mitochondrial disorders, was a distinctive characteristic of this case. When our patient was treated with hydrocortisone, in addition to ubiquinone and carnitine, the episodes of decompensation regressed and an improvement of the adrenal insufficiency, but only temporary reversion of the weakness of muscle, ophthalmoplegia and of the fatigue, were testified. Nevertheless, after a brief period of recovery, she developed the de Toni-Debré-Fanconi syndrome and the reappearance of the neurological symptoms.

Relationship between physical inactivity and adiposity in prepubertal boys.

OBJECTIVE: To study the relationship between the energy expenditure for activity (EEAct), the level of activity and adiposity in a group of 9-year-old boys (n = 28) with different body composition (body weight, 38 +/- 10 kg [range, 23 to 66 kg]; fat mass, 23% +/- 10% [range, 8% to 42%]). METHODS: Total energy expenditure (TEE) was measured by means of the heart-rate monitoring method. EEAct was calculated as TEE-(REE+0.1 TEE), where REE is the postabsorptive resting energy expenditure and 0.1 TEE corresponds to the postprandial thermogenesis (approximately 10% of TEE). RESULTS: TEE, REE, and EEAct were 9388 +/- 1859, 5154 +/- 642, and 3295 +/- 1356 l J/day, respectively. Daily time devoted to sedentary and nonsedentary activities averaged 290 +/- 155 minutes (range, 69 to 621) and 534 +/- 150 minutes (range, 180 to 783), respectively. Time spent on sedentary activities was directly proportional to fat mass percentage (r = 0.46; p < 0.05). It was the only variable, among the free-living physical-activity [EEAct, TEE/(REE+0.1 TEE) ratio, time spent in nonsedentary and sedentary activities] variables, which remained significantly in the multiple step-down regression analysis final equation (r = 0.46; p < 0.05). CONCLUSIONS: The positive relationship between adiposity and time spent on sedentary activities in 9-year-old boys suggests the importance of the role played by muscular activity, at least in the maintenance of obesity in childhood. Prepubertal children should be encouraged to spend less time on sedentary activities to treat and prevent their obesity.