Urine soluble TLR4 levels may contribute to predict urinary tract infection in children: the UTILISE Study.

BACKGROUND: One of the most common bacterial infections in childhood is urinary tract infection (UTI). Toll-like receptors (TLRs) contribute to immune response against UTI recognizing specific pathogenic agents. Our aim was to determine whether soluble TLR4 (sTLR4), soluble TLR5 (sTLR5) and interleukin 8 (IL-8) can be used as biomarkers to diagnose UTI. We also aimed to reveal the relationship between urine Heat Shock Protein 70 (uHSP70) and those biomarkers investigated in this study. METHODS: A total of 802 children from 37 centers participated in the study. The participants (n = 282) who did not meet the inclusion criteria were excluded from the study. The remaining 520 children, including 191 patients with UTI, 178 patients with non-UTI infections, 50 children with contaminated urine samples, 26 participants with asymptomatic bacteriuria and 75 healthy controls were included in the study. Urine and serum levels of sTLR4, sTLR5 and IL-8 were measured at presentation in all patients and after antibiotic treatment in patients with UTI. RESULTS: Urine sTLR4 was higher in the UTI group than in the other groups. UTI may be predicted using 1.28 ng/mL as cut-off for urine sTLR4 with 68% sensitivity and 65% specificity (AUC = 0.682). In the UTI group, urine sTLR4 levels were significantly higher in pyelonephritis than in cystitis (p < 0.0001). Post-treatment urine sTLR4 levels in the UTI group were significantly lower than pre-treatment values (p < 0.0001). CONCLUSIONS: Urine sTLR4 may be used as a useful biomarker in predicting UTI and subsequent pyelonephritis in children with UTI. A higher resolution version of the Graphical abstract is available as Supplementary information.

Henoch-Schonlein purpura, post-streptococcal glomerulonephritis and acute rheumatic carditis after Group A ß-haemolytic streptococcal infection.

Besides association with acute rheumatic fever (ARF) and acute glomerulonephritis (APSGN), in up to 40% of cases, Group A ß-haemolytic streptococcal (GABHS) infections are also implicated as a trigger for Henoch-Schonlein purpura (HSP). A 7-year-old girl with GABHS throat infection who developed HSP, APSGN and rheumatic carditis is reported. She presented with palpable purpura and arthritis in both ankles and later developed carditis characterised by mitral/aortic regurgitation and glomerulonephritis characterised by mixed nephritic/nephrotic syndrome. She had a raised anti-streptolysin titre (ASOT), blood urea nitrogen and creatinine and hypocomplementaemia (C3), and renal biopsy demonstrated endocapillary and extracapillary proliferative glomerulonephritis with crescents. Immunofluorescence microscopy demonstrated a 'full house' of immunoglobulin and complement, viz. IgA + 2, IgG + 3, IgM + 2, C3c + 1, Clq + 2 with predominantly IgG deposition. One week earlier, her 4-year-old sister had presented to another hospital with HSP complicated by microscopic haematuria, nephrotic-range proteinuria and gastro-intestinal involvement, and with raised ASOT and low C3 levels. Although HSP has been associated with either ARF or APSGN, this is the first case of a child with HSP, ARF and APSGN in combination.

Molecular characterization of cystinuria in south-eastern European countries.

Cystinuria is an autosomal recessive disorder caused by defective transport of cystine and dibasic amino acids in the proximal renal tubules and small intestine. So far, more than 128 mutations in SLC3A1 gene, and 93 in SLC7A9 gene have been described as a cause of cystinuria. We present a molecular characterization of the cystinuria in 47 unrelated south-east European families. The molecular methodology included direct sequencing, single strand conformational polymorphism, and restriction fragment length polymorphism. A total of 93 (94.9 %) out of 98 unrelated cystinuric chromosomes have been characterized. Mutations in SLC3A1 gene account for 64.3 % and in SLC7A9 gene for 30.6 % of the cystinuric chromosomes. Ten different mutations in SLC3A1 gene were found, and two of them were novel (C242R and L573X), while in SLC7A9 gene seven mutations were found, of which three were novel (G73R, V375I and c.1048_1051delACTC). The most common mutations in this study were T216M (24.5 %), M467T (16.3 %) and R365L (11.2 %) in SLC3A1 and G105R (21.4 %) in SLC7A9 gene. A population specificity of cystinuria mutations was observed; T216M mutation was the only mutation present among Gypsies, G105R was the most common mutation among Albanians and Macedonians, and R365L among Serbs. The results of this study allowed introduction of rapid, simple and cost-effective genetic diagnosis of cystinuria that enables an early preventive care of affected patients and a prenatal diagnosis in affected families.

Etiology and outcome of acute kidney injury in children.

The aim of this prospective, multicenter study was to define the etiology and clinical features of acute kidney injury (AKI) in a pediatric patient cohort and to determine prognostic factors. Pediatric-modified RIFLE (pRIFLE) criteria were used to classify AKI. The patient cohort comprised 472 pediatric patients (264 males, 208 females), of whom 32.6% were newborns (median age 3 days, range 1-24 days), and 67.4% were children aged >1 month (median 2.99 years, range 1 month-18 years). The most common medical conditions were prematurity (42.2%) and congenital heart disease (CHD, 11.7%) in newborns, and malignancy (12.9%) and CHD (12.3%) in children aged >1 month. Hypoxic/ischemic injury and sepsis were the leading causes of AKI in both age groups. Dialysis was performed in 30.3% of newborns and 33.6% of children aged >1 month. Mortality was higher in the newborns (42.6 vs. 27.9%; p < 0.005). Stepwise multiple regression analysis revealed the major independent risk factors to be mechanical ventilation [relative risk (RR) 17.31, 95% confidence interval (95% CI) 4.88-61.42], hypervolemia (RR 12.90, 95% CI 1.97-84.37), CHD (RR 9.85, 95% CI 2.08-46.60), and metabolic acidosis (RR 7.64, 95% CI 2.90-20.15) in newborns and mechanical ventilation (RR 8.73, 95% CI 3.95-19.29), hypoxia (RR 5.35, 95% CI 2.26-12.67), and intrinsic AKI (RR 4.91, 95% CI 2.04-11.78) in children aged >1 month.

Co-existence of chronic renal failure, renal clear cell carcinoma, and Blau syndrome.

Blau syndrome is a rare, multisystem, autosomal-dominant, and granulomatous disorder caused by susceptibility variants in the NOD2 gene. We describe here a 14-year-old girl with Blau syndrome with incidentally diagnosed renal carcinoma. The index case presented with growth retardation and recurrent symmetric arthritis. Her clinical symptoms included bilateral cataract due to recurrent uveitis, camptodactyly, and persistent erythematous rash with ichthyosis. Her two sisters and her mother were affected with combinations of these conditions-symmetric polyarthritis, uveitis, and skin involvement-suggesting an autosomal dominant trait. The index case developed a chronic renal insufficiency, and an abdominal computerized tomography scan revealed a 2.5-cm mass in the left kidney. The histopathological examination showed renal clear cell carcinoma, chronic tubulointerstitial nephritis,and giant cell granulomas in both the tumor and nonneoplastic renal tissue. Granulomatous inflammation was observed in the skin biopsy specimen. The patient was diagnosed with Blau syndrome based on her family history, uveitis, granulomatous inflammation proved by skin biopsy, and polyarthritis. Sequencing of the NOD2 gene showed a heterozygous p.R334Q mutation in all affected family members. To the best of our knowledge, this is the first reported case of a patient with Blau syndrome accompanied by chronic renal failure and renal carcinoma.

Kidney stone and urinary bladder telangiectasia in a patient with TAR syndrome.

TAR syndrome is a congenital malformation syndrome characterized by bilateral absence of the radius and thrombocytopenia. The known urinary anomalies are duplex ureter, dilatation of renal pelvis, horseshoe kidney and functional problems like vesicoureteral reflux and pyelonephritis. In this report of a case with TAR syndrome, a kidney stone and bladder telangiectasia were found coincidentally during the investigation of hematuria. TAR syndrome is discussed in the light of the medical literature. To our knowledge, no case has been reported demonstrating nephrolithiasis and bladder telangiectasia in TAR patients.

Reno-vascular hypertension in childhood: a nationwide survey.

Renovascular disease accounts for 8-10% of all cases of paediatric hypertension, whereas, in adults, its incidence is approximately 1%. The Turkish Paediatric Hypertension Group aimed to create the first registry database for childhood renovascular hypertension in Turkey. Twenty of the 28 paediatric nephrology centres in Turkey responded to the survey and reported 45 patients (27 girls, 18 boys) with renovascular hypertension between 1990 and 2005. The age at presentation ranged from 20 days to 17 years. The mean blood pressure at the diagnosis was 169/110 mmHg. Chief complaints of symptomatic patients were headache (38%), seizure (18%), epistaxis (4%), growth retardation (4%), cognitive dysfunction (4%), polyuria (2%), palpitation (2%), and hemiplegia (2%). Renovascular hypertension was found incidentally in 11 children. The diagnosis of renovascular hypertension was established with conventional angiography in 39 patients, MR angiography in three, CT angiography in two, and captopril diethylene triamine penta-acetic acid (DTPA) scintigraphy in one patient. Twenty-one children had bilateral renal artery stenosis and 24 had unilateral renal artery stenosis. Of these, 14 (31%) had fibromuscular dysplasia; 12 (27%) Takayasu's arteritis; six (13%) neurofibromatosis; two (5%) Williams syndrome; one (2%) Kawasaki disease; one (2%) mid-aortic syndrome; one (2%) extrinsic compression to the renal artery, and eight (18%) unspecified bilateral renal artery stenosis. Hypertension was controlled with antihypertensive drugs in 17 patients. Percutaneous transluminal angioplasty (PTRA) or surgery had to be performed in 28 patients: PTRA in 16 patients, PTRA + surgery in one patient and surgery in 11 patients (four nephrectomies). The importance of vasculitic disease, especially Takayasu's arteritis, should not be underestimated in children with renovascular hypertension.

Histopathological and ultrastructural effects of Losartan on embryonic rat kidney.

The aim of our study was to investigate the histopathological, immunohistochemical and ultrastructural effects of Losartan (a selective angiotensin II type-1 receptor blocker) on renal development in rats. Twelve pregnant rats were divided into control and experimental groups. In the experimental group, Losartan (10 mg/kg/day) was given via nasogastric tube, between the sixth day of implantation and time of sacrifice on embryonic days 18 and 20. All formalin-fixed, paraffin wax-embedded renal tissue sections were stained with hematoxylin and eosin or labelled for binding of primary antibodies against transforming growth factor-beta (TGF-beta 1,-2,-3) using an avidin-biotin-peroxidase method. For electron microscopic examination, samples were fixed with glutaraldehyde and osmium tetroxide and embedded in araldite. Glomerular basement membrane (GBM) thickness was measured and compared using an unpaired t-test. Angiotensin II type-1 receptor antagonism by Losartan inhibited renal growth and delayed nephron maturation. Increased immunoreactivity of TGF-beta's was observed in developing nephron precursors and interstitial cells in the experimental group. Electron microscopical examination showed that thickening of the GBM was normal in the control group but an irregular thickening was seen in the experimental group (p < 0.001). It was also seen that epithelial cells of developing tubules underwent apoptosis in the experimental group. Thus, renal development in rats seems to depend on an intact renin-angiotensin system.

Premedication during micturating cystourethrogram to achieve sedation and anxiolysis.

Micturating cystourethrogram (MCUG) is an imaging technique indicated in the diagnosis and follow-up of many diseases. We investigated the reliability and the efficacy of midazolam and chloral hydrate in sedation and anxiolysis during micturating cystourethrogram. Fifty-three children of similar ages (39 girls, 14 boys, mean age of 5.8+/-3.5 years) were randomized to midazolam (n=17), chloral hydrate (n=18) and control groups (n=18). Oral midazolam 0.6 mg/kg or chloral hydrate 25 mg/kg or saline were administered to the study groups 15-30 min prior to the urinary catheterization. Brietkopf and Buttner, Frankl and Houpt scales and Spielberger's State Anxiety Inventory and parent's impressions were used to assess the level of sedation and anxiety. The Brietkopf and Buttner classification of emotional status and Houpt behavior rating scale demonstrated a significantly better emotional status and sedation in the midazolam group when compared to controls (P=0.01 and P=0.018, respectively). The catheterization was described as a more unpleasant and distressing event by the parents of the control and the chloral hydrate groups when compared to the parents of the midazolam group (P<0.05). Bladder capacity and frequency of detection of residual urine were not statistically different between the three study groups (P>0.05). Vital signs did not change significantly in any child. Sedation with midazolam does not have adverse effects on the results of micturating cystourethrogram, while it reduces the discomfort in children undergoing this radiological technique.