Kidney volume normative values in Central European children aged 0-19 years: a multicenter study.

BACKGROUND AND OBJECITVES: The currently available kidney volume normative values in children are restricted to small populations from single-centre studies not assessing kidney function and including none or only a small number of adolescents. This study aimed to obtain ultrasound-based kidney volume normative values derived from a large European White/Caucasian paediatric population with normal kidney function. METHODS: After recruitment of 1427 children aged 0-19 years, 1396 individuals with no history of kidney disease and normal estimated glomerular filtration rate were selected for the sonographic evaluation of kidney volume. Kidney volume was correlated with age, height, weight, body surface area and body mass index. Kidney volume curves and tables related to anthropometric parameters were generated using the LMS method. Kidney volume predictors were evaluated using multivariate regression analysis with collinearity checks. RESULTS: No clinically significant differences in kidney volume in relation to height were found between males and females, between supine and prone position and between left and right kidneys. Males had, however, larger age-related kidney volumes than females in most age categories. For the prediction of kidney volume, the highest coefficient correlation was observed for body surface area (r = 0.94), followed by weight (r = 0.92), height (r = 0.91), age (r = 0.91), and body mass index (r = 0.67; p < 0.001 for all). CONCLUSIONS: This study presents LMS-percentile curves and tables for kidney volume which can be used as reference values for children aged 0-19 years.

Kidney length normative values - new percentiles by age and body surface area in Central European children and adolescents.

BACKGROUND: Kidney size evaluation is an essential examination in pediatric nephrology. While body length/height is the best predictor of kidney length, age-based and body surface area (BSA)-based normative values may be useful in clinical practice or research. This study aimed to establish ultrasound-based kidney length lambda-mu-sigma (LMS) percentiles by age and BSA in healthy children. METHODS: In 1758 Polish and Lithuanian children (868 boys, 49%) aged 0-19 years, kidney length was measured using ultrasonography. In all participants, anthropometric measurements were taken and kidney function was evaluated based on serum creatinine concentration. Participants with chronic or kidney diseases, abnormal kidney function, or pathologies in sonographic examination were excluded from the analysis. RESULTS: Kidney length (median kidney length) increased progressively from infancy to the age of 18 years, from 60.1 to 114.2 mm in males, and from 57.3 to 105.2 mm in females. A gradual increase of kidney length (50th percentile) in relation to BSA (from 46.1 mm in infants with a BSA of 0-1.2 m2 to 118.3 mm in adolescents with a BSA of 2.6-2.8 m2) was also observed. LMS percentiles by age (stratified by sex) and BSA were determined and presented as graphs and tables of percentiles and LMS parameters by 1-year age intervals and 0.2 m2 of BSA, respectively. CONCLUSIONS: We present the first age- and BSA-based kidney length LMS normative values based on the largest pediatric cohort to date, which can be used in both clinical practice and research studies. A higher resolution version of the Graphical abstract is available as Supplementary information.

New non-invasive biomarkers of intestinal inflammation and increased intestinal permeability in pediatric inflammatory bowel diseases and their correlation with fecal calprotectin: a pilot study.

BACKGROUND: Increased intestinal permeability is considered to play a crucial role in the pathogenesis of inflammatory bowel diseases (IBD). Therefore, recently, the use of non-invasive biomarkers in both diagnosis and monitoring IBD is emphasized. The aim of this study was to investigate fecal and serum zonulin and serum I-FABP in pediatric IBD patients and their correlation with fecal calprotectin (FCP). METHODS: Seventy-one individuals: 32 Crohn's disease (CD) patients, 33 ulcerative colitis (UC) patients and 6 controls were examined for fecal and serum zonulin and plasma I-FABP. Values were correlated to FCP and to each other for all children included in the study. A stool specimen and blood samples were collected during check-up visits at hospital. Then fecal and serum zonulin, I-FABP and FCP were tested by ELISA test. Non-parametric statistical tests were used for data analysis. RESULTS: The level of fecal zonulin and FCP were higher in IBD patients compared to control group (CG): median for CD - 46.0 (7.0-3854) ng/mL, 252.0 (77.0 -1054.2) ug/g; UC - 115.3 (50.7-418.3) ng/mL, 40 (16.0-1883.0) ug/g; CG - 60.8 (31.8-123.0) ng/mL, 41.5 (31.0-323.0) ug/g, respectively, (P<0.05). No statistically significant difference in concentrations of serum zonulin and I-FABP was reported between patients and CG (P=0.55). The only correlation that has been reported was between fecal zonulin and FCP and the strongest one was in CD: CD - R = 0.73, UC - R = 0.67, All - R=0.67, CG - R=0.65. CONCLUSIONS: According to our results it seems that only fecal zonulin may serve as another, next to FCP, biomarker of intestinal damage in IBD. However, both fecal and serum zonulin as well as IFABP need further studies to assess their usefulness in diagnostics and monitoring in IBD.

Distribution and maturation state of peripheral blood dendritic cells in children with primary hypertension.

Dendritic cells (DCs) play an important role in T cell alterations in primary hypertension (PH). We determined the numbers and maturation markers of peripheral blood total DCs (tDCs), myeloid cells (mDCs), and plasmacytoid cells (pDCs) and their association with hypertension-mediated organ damage (HMOD) markers and selected immune parameters in 30 adolescents with white coat hypertension (WCH), 25 adolescents with PH and a group of 35 age- and sex-matched children with normotension. Using multicolor flow cytometry, expression of maturation markers (CD86 and CD83) in tDCs (Lin1-/HLA-DR+), myeloid DCs (Lin1-/HLA-DR+/CD11c+) (mDCs), and plasmacytoid DCs (Lin1-/HLA-DR+/CD123+) (pDCs) and the distribution of peripheral Th17-bearing and T-reg cells were defined. In subjects with hypertension, carotid intima-media thickness (cIMT), left ventricular mass index (LVMI), and pulse wave velocity (PWV) were assessed. Compared with WCH and subjects with normotension, subjects with hypertension had reduced tDC and pDC numbers, an increased percentage of mDC subsets, an elevated mDC/pDC ratio, an increased population of mature mDC and pDC subsets bearing CD83 of high density, a decreased subset of CD86-bearing pDCs, and increased expression of DC activation markers (HLA-DR, CD86), as well as CD11c (mDCs) and CD123 (pDCs). PWV, LVMI, and cIMT values correlated negatively with tDCs and pDCs and positively with mDC numbers. Expression of DC maturation/activation markers (CD83, CD86, HLA-DR, CD11c, and CD123) correlated positively with PWV. Certain DC characteristics of WCH subjects resembled those of PH subjects (decreased tDC frequency and upregulation of activation marker expression). These changes correlated with HMOD. WCH subjects presented a DC phenotype that was intermediate between the normotensive and hypertensive phenotypes.

Fecal Zonulin as a Noninvasive Biomarker of Intestinal Permeability in Pediatric Patients with Inflammatory Bowel Diseases-Correlation with Disease Activity and Fecal Calprotectin.

BACKGROUND: Recent data indicate that increased intestinal permeability plays a key role in the pathogenesis of inflammatory bowel diseases (IBD) and correlates with disease flare. Since zonulin related proteins (ZRP) are the proteins that increase permeability in the epithelial layer of the small intestine by reversibly modulating the intercellular tight junctions, they may serve as a new, noninvasive biomarker of disease activity. The aim of this study was to investigate fecal ZRP in pediatric IBD patients as well as its correlation with disease activity and fecal calprotectin (FCP). METHODS: Ninety-four individuals: 47 Crohn's disease (CD) patients, 41 ulcerative colitis (UC) patients, and 6 healthy controls were examined for fecal ZRP. Values were correlated to IBD type, disease activity for IBD patients, and FCP for all children included in the study. A stool specimen was collected the day before the visit to the hospital, then fecal ZRP and FCP were tested using the ELISA test. Non-parametric statistical tests were used for data analysis. RESULTS: The level of fecal ZRP was higher among IBD patients compared to the control group (CG): medians for CD-113.3 (53.6-593.6) ng/mL; UC-103.6 (50.7-418.3) ng/mL; and CG-46.9 (31.8-123.0) ng/mL (p < 0.05). No difference in fecal ZRP concentration was observed between children with CD and those with UC (p = 0.55). A slight correlation between disease activity (PCDAI for CD and PUCAI for UC) and the fecal ZRP level was found for CD (p = 0.03/R = 0.33), but not UC (p = 0.62/R = 0.08), patients. A correlation between fecal ZRP and FCP was observed (R = 0.73, p = 0.00). CONCLUSIONS: Fecal ZRP levels are increased among those with IBD, are associated with CD activity, and strongly correlate with FCP. Further research into the role of intestinal permeability in IBD and the clinical usefulness of ZRP in IBD is warranted.

The carbon source-dependent pattern of antimicrobial activity and gene expression in Pseudomonas donghuensis P482.

Pseudomonas donghuensis P482 is a tomato rhizosphere isolate with the ability to inhibit growth of bacterial and fungal plant pathogens. Herein, we analysed the impact of the carbon source on the antibacterial activity of P482 and expression of the selected genes of three genomic regions in the P482 genome. These regions are involved in the synthesis of pyoverdine, 7-hydroxytropolone (7-HT) and an unknown compound ("cluster 17") and are responsible for the antimicrobial activity of P482. We showed that the P482 mutants, defective in these regions, show variations and contrasting patterns of growth inhibition of the target pathogen under given nutritional conditions (with glucose or glycerol as a carbon source). We also selected and validated the reference genes for gene expression studies in P. donghuensis P482. Amongst ten candidate genes, we found gyrB, rpoD and mrdA the most stably expressed. Using selected reference genes in RT-qPCR, we assessed the expression of the genes of interest under minimal medium conditions with glucose or glycerol as carbon sources. Glycerol was shown to negatively affect the expression of genes necessary for 7-HT synthesis. The significance of this finding in the light of the role of nutrient (carbon) availability in biological plant protection is discussed.

Analysis of vitamin D3 metabolites in survivors of infantile idiopathic hypercalcemia caused by CYP24A1 mutation or SLC34A1 mutation.

Infantile hypercalcemia (IH), is a rare disorder caused by CYP24A1 or SLC34A1 variants which lead to disturbed catabolism of 25(OH)D3 and 125(OH)2D3 or increased generation of 125(OH)2D3. AIM OF STUDY: To assess the status of 2425(OH)2D3 and other markers of vitamin D in IH survivors, in whom variants of CYP24A1 or SLC34A1 gene were found and to compare these unique biochemical features with those obtained from subjects who were diagnosed in the first year of life with hypercalcemia, elevated 25(OH)D3 and low PTH but in whom neither CYP24A1 nor SLC34A1 variant was found. PATIENTS AND METHODS: 16 IH survivors in whom CYP24A1 (n = 13) or SLC34A1 (n = 3) variants were found and 41 subjects in whom hypercalcemia was diagnosed in the first year of life but in whom CYP24A1 or SLC34A1 variants were not found were included in the study. 25(OH)D3, 3-epi-25(OH)D3, 25(OH)D2, 2425(OH)2D3 were assessed by liquid chromatography coupled with tandem mass spectrometry. 125(OH)2D3 concentrations were assessed by chemiluminescence. RESULTS: Subjects with CYP24A1 variants, despite normal 25(OH)D3 levels, had higher 25(OH)D3/2425(OH)2D3 ratio values (487; 265-1073 ng/mL) when compared to subjects with SLC34A1 variants (16; 16-23 ng/mL) and with subjects in whom CYP24A1 or SLC34A1 were not found (56; 9-56 ng/mL) (p = 0.00003). Separation of interfering metabolite further increased differences between subjects with and without CYP24A1 mutation. CONCLUSIONS: Survivors of IH with CYP24A1 variant, despite being normocalcemic, still presented extremely high 25(OH)D3/2425(OH)2D3 ratio values. Separation of interfering compound further increased differences between subjects with CYP24A1 mutation and without this mutation.

Long-term outcome of the survivors of infantile hypercalcaemia with CYP24A1 and SLC34A1 mutations.

BACKGROUND: Infantile hypercalcaemia (IH) is a vitamin D3 metabolism disorder. The molecular basis for IH is biallelic mutations in the CYP24A1 or SLC34A1 gene. These changes lead to catabolism disorders (CYP24A1 mutations) or excessive generation of 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] (SLC34A1 mutations). The incidence rate of IH in children and the risk level for developing end-stage renal disease (ESRD) are still unknown. The aim of this study was to analyse the long-term outcome of adolescents and young adults who suffered from IH in infancy. DESIGN: Forty-two children (23 girls; average age 10.7 ± 6.3 years) and 26 adults (14 women; average age 24.2 ± 4.4 years) with a personal history of hypercalcaemia with elevated 1,25(OH)2D3 levels were included in the analysis. In all patients, a genetic analysis of possible IH mutations was conducted, as well as laboratory tests and renal ultrasonography. RESULTS: IH was confirmed in 20 studied patients (10 females). CYP24A1 mutations were found in 16 patients (8 females) and SLC34A1 in 4 patients (2 females). The long-term outcome was assessed in 18 patients with an average age of 23.8 years (age range 2-34). The average glomerular filtration rate (GFR) was 72 mL/min/1.73 m2 (range 15-105). Two patients with a CYP24A1 mutation developed ESRD and underwent renal transplantation. A GFR <90 mL/min/1.73 m2 was found in 14 patients (77%), whereas a GFR <60 mL/min/1.73 m2 was seen in 5 patients (28%), including 2 adults after renal transplantation. Three of 18 patients still had serum calcium levels >2.6 mmol/L. A renal ultrasound revealed nephrocalcinosis in 16 of 18 (88%) patients, however, mild hypercalciuria was detected in only one subject. CONCLUSIONS: Subjects who suffered from IH have a greater risk of progressive chronic kidney disease and nephrocalcinosis. This indicates that all survivors of IH should be closely monitored, with early implementation of preventive measures, e.g. inhibition of active metabolites of vitamin D3 synthesis.

Atherosclerotic Risk Factors in Children with Celiac Disease.

RESULTS: We found significantly lower concentrations of total cholesterol, lipoprotein LDL-C, apolipoproteins A1 and B, as well as hCRP in all children with CD. We showed decreased level (<5 ng/mL) of folic acid among 46% of children treated for >5 years. Moreover, we showed significant decrease of folic acid level already after 1 year of a GFD (12 vs. 5.6 ng/mL; p < 0.001). We also found significant negative correlation of z-score body mass index (BMI) with HDL and APOA1 level (r = -0.33; p = 0.015 and r = -0.28; p = 0.038, respectively) and modest positive correlation of z-score BMI with atherogenic factor of total cholesterol-HDL ratio and LDL-HDL ratio (r = 0.40; p = 0.002 and r = 0.36; p = 0.006, respectively). Analysis of physical activity showed an increase in the insulin levels with inactivity (r = 0.36; p = 0.0025). We also found positive correlation of the sleep duration with the adiponectin level (r = 0.41; p = 0.011). CONCLUSIONS: In children with CD treated with a GFD, decreased level of folic acid together with increased BMI, sedentary behavior, and an improper lipid profile may predispose them to atherosclerosis in the long run. This data suggests the need of further studies to determine the need for metabolic cardiovascular risk screening in children with CD.

Regulatory T-cell subset distribution in children with primary hypertension is associated with hypertension severity and hypertensive target organ damage.

BACKGROUND: The relationship between circulating regulatory T-cell (Tregs) subset distribution and hypertension severity in children with primary hypertension is not known. We aimed to find out if target organ damage (TOD) in children with primary hypertension is related to defects in Tregs distribution reflected by their phenotype characteristics. METHODS: The study constituted 33 nontreated hypertensive children and 35 sex-matched and age-matched controls. Using multicolor flow cytometry technique, we assessed a distribution of the total Tregs (CD4CD25CD127) and their subsets (CD45RA-naive Tregs, CD45RA memory/activated Tregs, CD45RACD31 recent thymic emigrants Tregs and mature naive CD45RACD31 Tregs) in the whole blood. RESULTS: Hypertensive children showed decreased percentage of the total Tregs, the CD45RA-naive Tregs, the total CD31 Tregs and the recent thymic emigrants Tregs but elevation of the CD45RA memory/activated Treg and mature naive CD45RACD31 Tregs. Decreased frequency of the total Tregs, naive Tregs and CD31-bearing Treg cell subsets (CD31 total Tregs, CD45RACD31 recent thymic emigrants Tregs) negatively correlated to TOD markers, arterial stiffness and blood pressure elevation. In contrast, increased percentage of memory Tregs and CD31 Tregs subsets positively correlated to organ damage markers, arterial stiffness and blood pressure values. These changes were independent of BMI, age, sex and hsCRP. CONCLUSION: Both diagnosis of hypertension, TOD and arterial stiffness in hypertensive children were associated with decreased population of total CD4 Tregs, limited output of recent thymic emigrants Tregs, and increased pool of activated/memory Tregs. Hypertension was an independent predictor of the circulating Treg subsets distribution irrespective of hsCRP.

Leukocyte matrix metalloproteinase and tissue inhibitor gene expression patterns in children with primary hypertension.

Matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) play an important role in cardiovascular remodeling. The aim of the study was to analyze MMP/TIMP genes expression in peripheral blood leukocytes of 80 hypertensive children (15.1 ± 2.0 years) in comparison with age-matched 78 normotensive children (14.6 ± 2.0 years; n.s.). TIMP and MMP expression in peripheral blood leukocytes was assessed by quantitative real-time PCR. Hypertensive children independently of age, sex, and body mass index had greater expression of MMP-2 than normotensive controls (p = 0.0001). Patients with left ventricular hypertrophy had greater expression of MMP-14 than patients with normal left ventricular mass (p = 0.006) and TIMP-2 expression correlated with carotid wall cross-sectional area (p = 0.03; r = 0.238). MMP-14 expression correlated with BMI-SDS (p = 0.001; r = 0.371), waist circumference-SDS (p = 0.016; r = 0.290), hsCRP (p = 0.003; r = 0.350), serum HDL-cholesterol (p = 0.008; r = -0.304), and serum uric acid (p = 0.0001; r = 0.394). In conclusion, hypertensive adolescents presented significant alterations of MMP/TIMP expression pattern in comparison with normotensive peers. Moreover, altered MMP/TIMP expression was associated with hypertensive target organ damage and metabolic abnormalities.

Tryptophan-kynurenine profile in pediatric autoimmune hepatitis.

The impairment of regulatory T cells (Tregs) is a characteristic feature of autoimmune hepatitis (AIH), and the degradation of tryptophan (Trp) to kynurenine (Kyn), by gamma interferon-induced indoleamine-2,3-dioxygenase-1 (IDO-1), is a central metabolomics check point in the differentiation of Tregs. For this reason, we investigate whether or not Kyn and IDO activity is potentially useful biomarkers in pediatric AIH.Between January 2016 and January 2017, children of AIH type-1 (AIH-1, n = 37), AIH type-2 with liver kidney microsome-1 autoantibodies (AIH-2-LKM-1, n = 8), and autoantibody-negative Wilsons Disease (WD, n = 8) and alpha-1 anti-trypsin deficiency (AATD, n = 10), were enrolled in a cross-sectional survey of Kyn and Trp levels and Kyn/Trp ratios (IDO activity) by HPLC, and neopterin levels by ELISA.The mean Kyn and mean Kyn/Trp ratios of AIH-1 with smooth muscle antigen (SMA) 1.85 µM and 27 µmole/mmole, and AIH-2-LKM-1; 1.7 µM and 28.6 µmole/mmole were lower than that of the WD; 2.2 µM p = 0.03 and 33 µmole/mmole p = 0.02 and of AATD; 2.3 µM, p = 0.02 and 55 µM, p = 0.001. Kyn/Trp ratios of AIH relapse; 23.6 µmole/mmole were lower than Kyn/Trp ratios of AIH remission; 27.6 µmole/mmole (p < 0.05). The stage of liver disease and grade of liver biopsies in AIH-1 patients negatively correlated with the Kyn/Trp ratios.The serum Kyn levels and Kyn/Trp ratio of AIH patients, within or below the normal range, indicate a trend of IDO activity lower than non-autoimmune WD or AATD. Prospective monitoring of serum tryptophan metabolomics in larger cohorts of pediatric AIH patients is required to confirm the apparent paradigm of weak IDO activity contributing to the Treg deficit and pathogenesis of pediatric AIH.

Loss of CD31 receptor in CD4+ and CD8+ T-cell subsets in children with primary hypertension is associated with hypertension severity and hypertensive target organ damage.

BACKGROUND: Primary hypertension is associated with still poorly known T-cell dependent immunity defects that participate in the disease development. However, the relationship between peripheral T-cell subset distribution and disease severity in humans is not known. The aim of the study was to find out if target organ damage in adolescents with primary hypertension is associated with thymus-dependent lymphocytes renewal reflected by changes in the T-cell subset phenotype characteristics. METHODS: Using seven-color flow cytometry technique, we assessed CD31, CCR7 and CD28 receptors expression in CD45RA and CD45RO bearing peripheral CD4 and CD8 T-cell subsets. The study included 32 hypertensive children/adolescents and 35 sex-matched and age-matched controls. RESULTS: Children with primary hypertension had slightly increased CD4 T-cell pool but decreased population of CD31 expressing CD4 T-cell subsets (recent thymic emigrants). Frequency of the CD4 and CD4/CD45RA+ T cells lacking CD31 correlated positively with the hypertensive organ damage markers (pulse wave velocity, central blood pressure, left ventricular mass index). Left ventricular hypertrophy was associated with decreased CD4/CD45RA:CD4/CD45RO ratio, loss of the CD31 receptor in the CD4 and CD8 T-cell subsets and increased population of effector/memory T cells bearing CD8/CD28 and CD8/CD45RA+/CCR7 phenotype. Regression analysis revealed that these associations were independent of age, sex, and BMI. CONCLUSION: The results suggest that subclinical arterial injury and left ventricular hypertrophy in adolescents with primary hypertension is associated with declined thymic function and increased pool of T cells bearing effector/memory phenotype.

Obesity, lipid profiles and oxidative stress in children after liver transplantation.

PURPOSE: In adult liver transplant recipients, coronary artery disease and congestive heart failure are significant cause of morbidity and mortality. This may be attributed to the long-term immunosuppressive treatment, mostly with calcineurin inhibitors and steroids, which in long-term may be associated with hyperlipidemia, oxidative stress and cardiovascular complications. Since such data for children is sparse, the aim of this study was to assess the lipid and oxidative stress markers after pediatric liver transplantation (LTx). METHOD: We performed prospective analysis of 74 children, at the median age of 7.9 (2.8-11.6) years, 3.2 (1.2-4.3) years after LTx. We assessed the BMI Z-scores, cholesterol fractions (LDLc, HDLc, VLDLc), triglicerides, apolipoproteins (ApoAI, ApoB, ApoE), LCAT, insulin resistance by HOMA-IR and markers of oxidative stress and atherosclerosis: glutathione (GSH), glutathione peroxidase (GPx), asymmetrical dimethyl arginine (ADMA) and oxidized low-density lipoprotein (oxyLDL). At baseline, the results were compared with a healthy age-and-sex matched control group. After 3.1±0.3 year follow-up we repeated all investigations and compared them with the baseline results. RESULTS: At the baseline, we investigated 74 patients 3.2 (1.2-4.3) years after LTx, at the median age of 7.9 (2.8-11.6) years. The prevalence of overweight or obesity (BMI >85th percentile) was 23% and was more common in girls (24% vs 20%). Fourteen patients had TCH >200 mg%, 9 patients had LDLc >130 mg% and TG were at normal levels in all patients. Compared to the controls, there were no significant differences in lipid profiles but we found decreased GSH (p<0.001) and GPx (p<0.001) which play role as an antioxidant defense. OS markers were higher in the study group: ADMA (p<0.001), and oxyLDL (p<0.0001). Insulin resistance by HOMA-IR was increased in the study group (p=0.0002) but fasting glucose remained within normal ranges in all patients. After 3.1-year follow-up, the BMI >95th and >85Th percentile was present in 8% and 14% respectively. ADMA and oxyLDL decreased, whilst GSH and GPx increased when compared to the baseline. There was also significant decrease in apoB and Lp(a). CONCLUSION: Children after LTx had normal lipid profiles when compared to controls, however there is a tendency for hypercholesterolemia and obesity, which may play a role in cardiovascular complications in the future. Some markers of oxidative stress were increased after LTx, however further investigations are required to establish its clinical significance.

A heterozygous mutation in GOT1 is associated with familial macro-aspartate aminotransferase.

BACKGROUND & AIMS: Macro-aspartate aminotransferase (macro-AST) manifests as a persistent elevation of AST levels, because of association of the protein with immunoglobulins in the circulation. Macro-AST is a rare, benign condition without a previously confirmed genetic basis. METHODS: Whole exome sequencing (WES)-based screening was performed on 32 participants with suspected familial macro-AST, while validation of variants was performed on an extended cohort of 92 probands and 1,644 healthy controls using Taqman genotyping. RESULTS: A missense variant (p.Gln208Glu, rs374966349) in glutamate oxaloacetate transaminase 1 (GOT1) was found, as a putative causal variant predisposing to familial macro-AST. The GOT1 p.Gln208Glu mutation was detected in 50 (54.3%) of 92 probands from 20 of 29 (69%) families, while its prevalence in healthy controls was only 0.18%. In silico analysis demonstrated that the amino acid at this position is not conserved among different species and that, functionally, a negatively charged glutamate on the GOT1 surface could strongly anchor serum immunoglobulins. CONCLUSIONS: Our data highlight that testing for the p.Gln208Glu genetic variant may be useful in diagnosis of macro-AST. LAY SUMMARY: Higher than normal levels of aspartate aminotransferase (AST) in the bloodstream may be a sign of a health problem. Individuals with macro-AST have elevated blood AST levels, without ongoing disease and often undergo unnecessary medical tests before the diagnosis of macro-AST is established. We found a genetic variant in the GOT1 gene associated with macro-AST. Genetic testing for this variant may aid diagnosis of macro-AST.

Biallelic mutations in CYP24A1 or SLC34A1 as a cause of infantile idiopathic hypercalcemia (IIH) with vitamin D hypersensitivity: molecular study of 11 historical IIH cases.

Idiopathic infantile hypercalcemia (IIH) is a mineral metabolism disorder characterized by severe hypercalcemia, failure to thrive, vomiting, dehydration, and nephrocalcinosis. The periodical increase in incidence of IIH, which occurred in the twentieth century in the United Kingdom, Poland, and West Germany, turned out to be a side effect of rickets over-prophylaxis. It was recently discovered that the condition is linked to two genes, CYP24A1 and SLC34A1. The aim of the study was to search for pathogenic variants of the genes in adult persons who were shortlisted in infancy as IIH caused by "hypersensitivity to vit. D". All persons were found to carry mutations in CYP24A1 or SLC34A1, nine and two persons respectively. The changes were biallelic, with one exception. Incidence of IIH in Polish population estimated on the basis of allele frequency of recurrent p.R396W CYP24A1 variant, is 1:32,465 births. It indicates that at least a thousand homozygotes and compound heterozygotes with risk of IIH live in the country. Differences in mechanism of developing hypercalcemia indicate that its prevention may vary in both IIH defects. Theoretically, vit. D restriction is a first indication for CYP24A1 defect (which disturbs 1,25(OH)2D degradation) and phosphate supplementation for SLC34A1 defect (which impairs renal phosphate transport). In conclusion, we suggest that molecular testing for CYP24A1 and SLC34A1 mutations should be performed in each case of idiopathic hypercalcemia/hypercalciuria, both in children and adults, to determine the proper way for acute treatment and complications prevention.

Influence of Partial External Biliary Diversion on the Lipid Profile in Children With Progressive Familial Intrahepatic Cholestasis.

OBJECTIVES: The concentration of bile acids is highly increased in progressive familial intrahepatic cholestasis (PFIC). Bile acids are the end products of cholesterol metabolism, and aid in the absorption of fat-soluble vitamins and dietary fat. The aim of our study was to investigate lipid metabolism in patients with PFIC with focus on the effect of partial external biliary diversion (PEBD). METHODS: In 26 patients with PFIC, who underwent PEBD surgery at the median age of 2.2 years (range: 0.4-16.6), we analyzed the concentrations of lipids and apolipoproteins both before and 6 months after PEBD. Patients were split into 2 groups according to the outcome of surgery (either "good" or "poor"), and were analyzed separately. A "good" result following surgery was defined as complete relief from pruritus, and normalization of total bilirubin (<1.0 mg/dL) and bile acid concentration in serum (<12 µmol/L). RESULTS: We found abnormal lipid concentrations at baseline in all 26 patients: cholesterol was increased (>190 mg/dL) in 13 patients, phospholipids were increased (>250 mg/dL) in 5 patients, and triglyceride concentration was increased (>150 mg/dL) in 13 patients. After PEBD, the concentrations of plasma cholesterol, triglycerides, and phospholipids decreased significantly, whereas, ApoA-I and high-density lipoprotein cholesterol concentrations increased and the concentrations of apolipoprotein B, low-density lipoprotein cholesterol, and very low-density lipoprotein cholesterol significantly decreased. PEBD had neither an effect on ApoE concentration nor on lecithin-cholesterol acyl transferase activity. In the group with a "poor" outcome report following PEBD, total serum cholesterol concentration decreased significantly, and no effect on the concentrations of triglycerides and phospholipids were observed. CONCLUSIONS: Patients with PFIC present with a high risk of lipid disturbances. PEBD has a beneficial effect on lipid profile in the majority of cases.

Exocrine pancreatic function in children with Alagille syndrome.

Alagille syndrome (AGS) is often associated with symptoms of maldigestion, such as steatorrhea, hypotrophy and growth retardation. Exocrine pancreatic insufficiency was proposed as the underlying cause. We aimed to assess the exocrine pancreatic function with the use of different methods in AGS patients. Concentrations of fecal elastase-1 (FE1) and fecal lipase (FL) activities were measured in 33 children with AGS. The C-mixed triglyceride breath test (MTBT) in a subgroup comprising 15 patients. In all patients studied, FE1 concentrations and FL activities were normal. Abnormal MTBT results were documented in 4 (26.7%) patients. The FE1 and FL levels in MTBT-positive and MTBT-negative children did not differ. The results of this research do not confirm the presence of exocrine pancreatic dysfunction in AGS patients. Routine screening for exocrine pancreatic insufficiency of this group of patients is not necessary.

Altered matrix metalloproteinase 9 and tissue inhibitor of metalloproteinases 1 levels in children with primary hypertension.

BACKGROUND: Matrix metalloproteinases (MMP) and tissue inhibitors of metalloproteinases (TIMP) are involved in cardiovascular remodeling in hypertension. Because metabolic abnormalities typical of metabolic syndrome is the dominant phenotype of primary hypertension in children, we hypothesized that MMP-9 and TIMP-1 plasma concentrations are altered in hypertensive children and correlate with metabolic abnormalities and target organ damage. METHOD: A total of 109 children (15.6, 10-17 years) with untreated primary hypertension were included to the study. The control group consisted of 74 healthy, normotensive children. RESULTS: Plasma MMP-9, TIMP-1 concentrations, and MMP-9/TIMP-1 ratio were significantly elevated in hypertensive boys in comparison with normotensive boys (P = 0.0001, P = 0.04, and P = 0.001, respectively), whereas there were no differences between hypertensive and normotensive girls. The levels of MMP-9 and TIMP-1 as well as MMP-9/TIMP-1 ratio were not associated either with hypertension stage, left ventricular hypertrophy, or carotid intima-media thickness. However, in a subgroup of 30 hypertensive patients in whom arterial stiffness was measured, TIMP-1 concentrations correlated with aortic pulse pressure (P < 0.05; r = 0.367), augmentation pressure (P < 0.05; r = 0.428), and augmentation index (P < 0.05; r = 0.404).Only hypertensive boys presented negative correlations of both MMP-9 and TIMP-1 levels with high-density lipoprotein cholesterol (r = -0.254, P = 0.01 and r = -0.241, P = 0.02, respectively). CONCLUSION: Hypertensive boys but not girls had elevated MMP-9 and TIMP-1 plasma concentrations, which indicates sex-related role of MMP/TIMP system in pediatric hypertension. The correlation between serum TIMP-1 and markers of arterial stiffness indicates on the involvement of TIMPs in arterial remodeling.

Leptin and Adiponectin Serum Levels from Infancy to School Age: Factors Influencing Tracking.

BACKGROUND: Early adiponectin and leptin in children correlate with those measured at a later age. Prenatal and early life factors may influence the pattern of leptin and adiponectin longitudinal changes. We aimed to identify subgroups of children with distinct trajectories of leptin and adiponectin over the first eight years of life, and to explore determinants predisposing an individual to be included in a specific trajectory class. METHODS: The analysis was based on data obtained from the EU Childhood Obesity Project (CHOP) cohort. The current study involved 459 children with adiponectin and leptin measured at 6 months, 5½ and 8 years of age. RESULTS: Three groups of leptin trajectories were identified: low-decreasing, medium-stable, and high-increasing, and two trajectory groups for adiponectin: lower and higher. The risk to be classified in the high-increasing group was higher than in the low-decreasing group for female gender (OR 10.67; 95% CI 4.94-23.05; p < 0.001); formula feeding (OR 3.34; 95% CI 1.11-10.09; p < 0.05); maternal overweight (OR 4.43; 95% CI 2.20-8.94; p < 0.001); and smoking in pregnancy (OR 4.14; 95% CI 2.07-8.29; p < 0.001). No predictors for being in the higher vs. lower adiponectin group were discovered. CONCLUSIONS: Mothers' smoking during pregnancy, maternal overweight, and formula feeding distinguished different courses of leptin trajectories; but the effect may be associated with changes in adiposity.