Composition of urinary calculi: Lessons from a French epidemiologic retrospective study.

INTRODUCTION: Urolithiasis is a common urological disease whose incidence increases in developed countries. We studied relations between composition of urinary calculi, age and gender. MATERIAL: An epidemiologic study was conducted in a French population of patients encountered analysis of urinary calculi between 2013 and 2017. This retrospective cohort study was performed from urinary calculi samples analysed in a clinical biochemistry laboratory of University Hospital of Lyon in France. A total of 5782 samples were included. Data, according to stone composition, presence of a papillary umbilication and a Randall's plaque, age and gender, were investigated. Statistical analyses used the Chi2 test (R software). RESULTS: The overall male to female sex ratio was equal to 1.76. The average and the median of age were 52.1 and 53.0 years, respectively. Whewellite was the most frequent main component in our population (44.4%). Carbapatite, weddellite and uric acid represented the main component in 14.0%, 13.4% and 13.0% of samples, respectively. Differences between genders were shown. Whewellite and uric acid were more frequent in men (P<0.001), while carbapatite and struvite were predominant in women (P<0.001). CONCLUSIONS: Our study provided recent data on the composition of urinary calculi in a French population and the relations between composition of urinary calculi and age and gender. LEVEL OF EVIDENCE: 3.

Implication of reward alterations in the expression of negative symptoms in 22q11.2 deletion syndrome: a behavioural and DTI study.

BACKGROUND: Alterations of the reward system have been proposed as one of the core mechanisms underlying the expression of negative symptoms in schizophrenia. Specifically, deficits in specific reward components and white matter (WM) integrity of the reward system have been highlighted. The putative link between negative symptoms and the hedonic experience, or structural connectivity of the reward system has never been examined in the 22q11.2 deletion syndrome (22q11DS), a condition with increased risk for psychosis. METHOD: Anticipatory and consummatory dimensions of pleasure were assessed in participants with 22q11DS (N = 54) and healthy controls (N = 55). In patients with 22q11DS, the association between pleasure scores and positive or negative symptoms was investigated. Furthermore, WM integrity of the accumbofrontal tract was quantified using diffusion tensor imaging (DTI). Associations between DTI measures, pleasure dimensions and negative symptoms were examined. RESULTS: Patients with 22q11DS showed reduced anticipatory and consummatory pleasure compared to controls. Furthermore, anticipatory pleasure scores were negatively correlated to negative and positive symptoms in 22q11DS. WM microstructural changes of the accumbofrontal tract in terms of increased fractional anisotropy and reduced radial anisotropy were also identified in patients. However, no significant correlation between the DTI measures and pleasure dimensions or psychotic symptoms was observed. CONCLUSIONS: This study revealed that participants with 22q11DS differed in their experience of pleasure compared to controls. The anticipatory pleasure component appears to be related to negative and positive symptom severity in patients. Alterations of WM integrity of the accumbofrontal tract seem to be related to myelination abnormalities in 22q11DS patients.

SenseCam: A new tool for memory rehabilitation?

The emergence of life-logging technologies has led neuropsychologist to focus on understanding how this new technology could help patients with memory disorders. Despite the growing number of studies using life-logging technologies, a theoretical framework supporting its effectiveness is lacking. This review focuses on the use of life-logging in the context of memory rehabilitation, particularly the use of SenseCam, a wearable camera allowing passive image capture. In our opinion, reviewing SenseCam images can be effective for memory rehabilitation only if it provides more than an assessment of prior occurrence in ways that reinstates previous thoughts, feelings and sensory information, thus stimulating recollection. Considering the fact that, in memory impairment, self-initiated processes are impaired, we propose that the environmental support hypothesis can explain the value of SenseCam for memory retrieval. Twenty-five research studies were selected for this review and despite the general acceptance of the value of SenseCam as a memory technique, only a small number of studies focused on recollection. We discuss the usability of this tool to improve episodic memory and in particular, recollection.

[Diagnosis and management of chronic kidney disease in children: Guidelines of the French Society of Pediatric Nephrology]. / Diagnostic et prise en charge de la maladie rénale chronique de l'enfant : recommandations de la Société de néphrologie pédiatrique (SNP).

These guidelines are intended to assist physicians in the care of children with chronic kidney disease (CKD), defined in children as in adults, regardless of its cause. Often silent for a long time, CKD can evolve to chronic renal failure or end-stage renal disease. Its management aims at slowing disease progression and treating CKD complications as soon as they appear. The different aspects of pediatric CKD care are addressed in these guidelines (screening, treatment, monitoring, diet, quality of life) as proposed by the French Society of Pediatric Nephrology. Highly specialized care provided in the hospital setting by pediatric nephrologists is not detailed.

[Relationship between glomerular filtration rate, uric acid, and parathyroid hormone in children]. / Relation entre débit de filtration glomérulaire, parathormone et acide urique chez l'enfant.

INTRODUCTION: Parathyroid hormone (PTH) and uric acid (UA) levels increase early during chronic kidney disease (CKD). The objective of this study was to evaluate the relationship between these two parameters at different stages of pediatric CKD. PATIENTS AND METHODS: One hundred patients (range, 5-18 years) were included in this retrospective study: they had undergone renal exploration with a direct measurement of the glomerular filtration rate (GFR) using the reference standard (i.e., inulin clearance, Cin) and presented with increased circulating levels of PTH and/or UA. RESULTS: GFR was normal in 39% of patients, with UA increased in 44% and PTH in 75% of them. Interestingly, 29% of the children with increased PTH levels had a strictly normal GFR (i.e., above 90 mL/min/1.73 m(2)). An inverse association was found between UA and GFR (r=-0.452, P ≤ 0.0001) as well as between PTH and GFR (r=-0.226, P=0.024). The same negative relationships were found between UA and PTH (r=-0.266, P=0.007), and between UA and the phosphate reabsorption rate (r=-0.415, P<0.001). DISCUSSION: Since hyperuricemia was found at all stages of CKD, an early silent tubular impairment can be discussed to explain these findings. The early increase in PTH levels during CKD has not been described by all authors, with North American studies describing rather late increased PTH levels during CKD. Prospective studies are required to confirm these data and evaluate the role of UA in the pathophysiology of the mineral disorders observed during CKD.

Comparison of cystatin C- and creatinine-based glomerular filtration rate formulas with inulin clearance in pediatric renal transplantation.

BACKGROUND: It has been suggested that plasma cystatin C (Cyst-C) concentrations provide better indicators of changes in glomerular filtration rate (GFR) than plasma creatinine concentration (PCr). METHODS: We compared the performance of five equations--2009 Schwartz, Local Schwartz, Larsson, Le Bricon, and Schwartz Combined--in 60 renal transplant children by calculating the mean bias, Pearson correlation coefficient (R) and determination (R2), 10% (P10) and 30% (P30) accuracies, and Bland-Altman plots. GFR was measured by inulin clearance. RESULTS: For the whole population, R2 was slightly lower for formulas based on Cyst-C or PCr, but the mean bias was lower, and P10 and P30 were greater, than using combined Schwartz equation. However, the mean estimated GFR by Schwartz 2009, Local Schwartz, and Schwartz combined equations was not statistically different from the mean inulin clearance measurement. CONCLUSIONS: In our pediatric transplant population, the combined Schwartz formula exhibited better performance to estimate GFR than formulae based on Cyst-C or combined PCr.

[Vitamin D revisited: a cornerstone of health?]. / Vitamine D : un acteur majeur en santé ?

There is a recent renewed interest in vitamin D metabolism and pathophysiology, due to its recent description as a hormone with a positive impact on global health rather than a strictly bone hormone: vitamin D could be a protective factor against infection, autoimmunity, cardiovascular morbidity, and cancer. By contrast, vitamin D deficiency appears to be increasingly frequent worldwide. We propose a review of these new aspects of vitamin D metabolism, with a focus on vitamin D status in a local pediatric cohort. There is an urgent need for revisiting current guidelines on vitamin D supplementation and for closely monitoring serum vitamin D in children with chronic diseases, i.e., at greater risk of cardiovascular impairment, bone morbidity, infectious disease, and acute inflammation.

[Long term renal outcome of children born preterm: a regular follow-up is needed]. / Devenir rénal des enfants nés grands prématurés: un suivi simple mais régulier est nécessaire.

Most of the published studies evaluating renal prognosis of children born very preterm found asymptomatic abnormalities (blood pressure, glomerular filtration rate GFR, hypercalciuria, decreased renal size, microalbuminuria...) during childhood or early adulthood. The objective of this study was to assess renal function (inulin clearance) in a prospective single-center cohort of children born preterm between 1998 and 2001 (< 30 GW,<1000 g) and to identify neonatal risk factors for renal abnormalities during childhood. Fifty children were included in the final part of the study. At a mean age of 7.6 years, no patient had arterial hypertension or chronic kidney disease, but mean centile for diastolic blood pressure was higher than expected and ultrasounds revealed small-sized kidneys compared to controls. The average GFR was 112 ml/min per 1.73 m(2) (91-158). Two children had microalbuminuria, two had hypercalciuria and one had nephrocalcinosis. Children with intra- or extra-uterine growth retardation had an impaired GFR compared to children with appropriate pre- and post-natal growth (107 vs. 110 vs. 125 ml/min per 1.73 m(2), p<0.05). Children with bronchopulmonary dysplasia had a significant higher microalbuminuria. In conclusion, findings of borderline blood pressure and reduced kidney size in children born preterm can be regarded as markers of reduced nephron number. Long term renal follow-up (blood pressure, serum creatinine, urine albumin / creatinine ratio) should be performed in all children born very preterm, with an early referring when abnormalities are highlighted.

Long-term renal and hearing toxicity of carboplatin in infants treated for localized and unresectable neuroblastoma: results of the SFOP NBL90 study.

BACKGROUND: A secondary end point of the NBL90 protocol (Rubie H et al. Pediatr Oncol 2001;36:247-250) was the concern in this infant population for possible carboplatin-(CBDCA) induced late side effects including impaired renal and hearing functions. PROCEDURE: Glomerular filtration rate (GFR), tubular function (TF), pure tone audiometry (PTA), high-frequency, and transient evoked-otoacoustic emission were prospectively assessed in 30 children alive and disease-free 6 years after the end of the treatment. RESULTS: Median age at diagnosis and at assessment was 4.7 months and 7 years, respectively. Blood pressure was < or =97.5 centile in all children. The mean estimated GFR was 114 +/- 13 ml/min/1.73 m(2) by Schwartz formula [range 87-145]. TF assessment failed to demonstrate any impairment. 29/30 children had grade 0 ototoxicity and all transient evoked otoacoustic emission were normal. CONCLUSIONS: With a 6-year follow-up the combination of VP16 and carboplatin given at conventional doses is safe on renal and hearing functions in infants with unresectable neuroblastomas treated according to SFOP NB90.

Renal outcome of children exposed to cyclosporine in utero.

The number of pregnancies in immunosuppressed women has increased during the recent years and this has become a major part of the rehabilitation and quality of life of treated patients. Most of them are organ transplant recipients and large series from the literature have shown that children born to such women may present with intrauterine growth retardation, a condition which may be associated with significant reduction in nephron number and oligomeganephronia. On the other hand, experimental data in animals have demonstrated that in utero exposure to CsA may alter nephrogenesis and further alter renal function. Therefore offspring of organ transplant women treated with CsA exhibit a theoretical risk of renal impairment, due to both IUGR and fetal nephrotoxicity. However, despite the limited experience of long term studies in children, there is no evidence of any significant deleterious adverse effect of in utero exposure to CsA. However further studies based on large series are required in order to demonstrate that renal fetal effects have limited clinical consequences.

Acute renal failure in a patient with phosphofructokinase deficiency.

A 16-year-old Caucasian girl was admitted to hospital with acute renal failure and hemolytic anemia due to rhabdomyolysis following a 3-km walk. (31)P-magnetic resonance spectroscopy provided characteristic spectra of type VII glycogen storage disease (phosphofructokinase deficiency).

Association between antioxidant nutritional indicators and the incidence of dementia: results from the PAQUID prospective cohort study.

OBJECTIVE: To analyse the relation between antioxidant vitamins A, E, and malondialdehyde (MDA) lipoperoxidation product plasma concentrations with incident dementia. DESIGN: : A nested case-control within the PAQUID (Personnes Agées QUID) cohort. SETTING: The PAQUID population-based prospective cohort in southwestern France. SUBJECTS: Among 626 subjects with blood collection at baseline, 46 developed a dementia during the follow-up and were considered to be cases. Each case was matched (on age and sex) to three controls. RESULTS: Plasma vitamin E concentrations were lower among cases (mean value at 22.62 micromol/l (s.d.: 7.38) vs 24.99 (s.d.: 6.73 among controls). The same trend was observed for vitamin A concentrations, but the difference was not significant. On the contrary, MDA concentrations tended to be higher (mean value 1.35 micromol/l (s.d.: 0.53) vs 1.23 (s.d.: 0.44)) among cases. In logistic regression models, plasma values were split into tertiles. Adjusted for confounders, the risk of dementia was significantly increased in the lowest vitamin E tertile (< or =21.0 micromol/l) (OR=3.12, P=0.033) compared to the highest one (> or =25.5 micromol/l). The risk of Alzheimer's disease was also increased, with borderline significance (OR=3.06, P=0.053). Risks associated with vitamin A were nonsignificant. Similarly, there was a trend to an increased risk of dementia in the highest tertile of MDA (OR=1.67, P=0.31). CONCLUSIONS: These results suggest that subjects with low plasma vitamin E concentrations are at a higher risk of developing a dementia in subsequent years.

Carbon 13 NMR spectroscopy: a powerful tool for studying renal metabolism.

Using precise examples, this paper shows that carbon 13 NMR spectroscopy in conjunction with radioactive and enzymatic methods as well as with adequate mathematical modeling of metabolic pathways allows not only to identify but also to quantify fluxes through enzymes involved in substrate and drug metabolism. Carbon 13 NMR spectroscopy is a tool of unprecedented power to unravel the complexity of renal metabolism. Currently it plays a major role in what is nowadays called metabolomics.

Fading renal hyperfiltration in children following liver transplantation.

In a prospective longitudinal study, we investigated the renal function (RF) of 23 children before and after orthotopic liver transplantation (OLT). The aim was to assess both the outcome of pretransplant hyperfiltration and the clinical nephrotoxic effects of cyclosporin A (CsA); children with decreased RF prior to OLT were therefore excluded. The RF study of the 13 remaining patients included glomerular filtration rate (GFR) and effective renal plasma flow (RPF) measured by inulin (Cin: mL/min/1.73 m2) and para-amino hippurate (Cpah: mL/min/1.73 m2) clearances, respectively. Hyperfiltration prior to OLT was observed in six children, i.e. Cin>170 [range 172-230] and Cpah>800 [808-1,133]. A significant decrease in RF was noted as soon as 6 months after OLT: Cin (mean+/-SD)=107+/-23 vs. 158+/-46 (p<0.003); Cpah=583+/-119 vs. 791+/-243 (p<0.004). This was due to loss of hyperfiltration in the six children, as there was no significant difference in RF before and 6 months after OLT in the other seven children. With a 36-month follow-up, there was no correlation between CsA trough blood level and RF. In conclusion, following OLT, RF underwent early changes owing to loss of prior hyperfiltration in children without impaired RF before OLT. In addition, no evidence of CsA nephrotoxicity was found and RF remained stable during follow-up.

Vesicoureteral reflux after kidney transplantation in children.

BACKGROUND: The prevalence and significance of vesicoureteral reflux (VUR) after kidney transplantation in adults varies between authors and there have been few reports in children. METHODS: We conducted a retrospective study in a single-centre paediatric cohort. Fifty-five of the 84 children who underwent kidney transplantation over a 5-year period were checked with routine cystography after a median of 8 months post-transplantation. Graft function and urinary-tract infections were assessed during the first 6 years after transplantation. RESULTS: VUR into the graft was present in 58% of the patients. Graft function and incidence of urinary-tract infections were similar in the two groups, independent of VUR. After having excluded infections attributed to the presence of a catheter, actuarial survival rates without pyelonephritis and without pyelonephritis following a first lower urinary-tract infection were worse in patients with VUR (P:=0.017 and P:=0.0039 respectively). None of the eight patients with VUR treated with antibiotic prophylaxis after a first acute pyelonephritis (APN) episode presented subsequent APN after 4.4+/-3.3 years on therapy. CONCLUSIONS: VUR to the graft occurred in more than half paediatric renal transplant recipients. This condition was associated with an increased risk of APN. Long-term antibiotic prophylaxis seems to be able to prevent APN in transplanted children with VUR.

Renal function of children exposed to cyclosporin in utero.

BACKGROUND: The use of cyclosporin (CsA) has improved graft survival in transplant (Tx) patients despite its potential nephrotoxicity. Children born to transplanted women may present with intrauterine growth retardation (IUGR). On the basis of potential reduced nephron mass both in IUGR and in newborn experimental animals exposed to CsA in utero, we investigated the renal function of children >1 year of age born to women under maintenance immunosuppression, including CsA. METHODS: Fourteen children born to 12 Tx women (nine kidney, one pancreas-kidney, one heart, one liver) were investigated using inulin clearance (C(in)), para-aminohippuric acid clearance (C(PAH)), microalbuminuria, and electrolyte reabsorption rate. RESULTS: Gestational age of the 14 infants was 34+/-3 weeks and birth weight 2018+/-620 g. During pregnancy, CsA trough blood level was 234+/-115 microg/l and plasma creatinine range was 96-136 micromol/l. Two children were excluded from the study because renal investigation led to a diagnosis of hereditary nephritis (one Alport syndrome, one familial dominant focal segmental glomerulosclerosis) that was retrospectively completed in the mother. Renal function tests were finally performed in 12 children at 2.6+/-1.8 years of age: BP 94+/-7/55+/-5 mmHg, C(in) 117+/-28 ml/min/1.73 m(2), C(PAH) 545+/-124 ml/min/1.73 m(2), filtration fraction 0.23+/-0.03, microalbuminuria 4.2+/-3.5 mg/mmol. Electrolyte tubular reabsorption rates and urine concentrating capacity were normal. CONCLUSION: These results suggest that in children born to transplanted women taking CsA, renal function develops normally despite prolonged exposure in utero.

Torasemide is an effective diuretic in the newborn rabbit.

The effect of intravenous (i.v.) torasemide on diuresis and renal function was evaluated in three groups of normoxemic, 5- to 10-day-old, newborn New Zealand White rabbits. The animals of group 1 received 0.2 mg/kg of torasemide i.v., whereas in group 2 an i.v. dose of 1.0 mg/kg was given. The third group of animals received a bolus i.v. dose of 1.0 mg/kg torasemide with continuous i.v. replacement of estimated urinary fluid and electrolyte losses. Torasemide proved to be an effective, potassium-sparing diuretic, without significant effect on glomerular filtration rate (GFR). Renal blood flow (RBF) fell and the renal vascular resistance (RVR) rose in all three groups of animals, although the rise in RVR in group 3 was not significant. These changes in renal hemodynamics were most pronounced in the animals of group 2 and are probably secondary to torasemide-induced hypovolemia (2.8% loss of body weight) and accompanying humoral reactions, such as an increase in angiotensin II (not measured). When the latter is prevented by simultaneous re-infusion of an electrolyte solution (group 3), replacing urinary losses, GFR increases and the changes in RBF and RVR are blunted. We conclude that torasemide is an effective, potassium-sparing diuretic in newborn rabbits. No evidence was found for a vasodilatory action of the drug.