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Author(s): Cailin E. Kellum [sup.1] , Keri M. Kemp [sup.1] , Sylvie Mrug [sup.3] , Jennifer S. Pollock [sup.1] , Michael E. Seifert [sup.2] , Daniel I. Feig [sup.2] Author [...], Background Adverse childhood experiences (ACEs), such as abuse, neglect, and household dysfunction, are associated with a higher risk of cardiovascular disease (CVD) and indicators of future CVD risk in adulthood, such as greater vascular stiffness. The impact of ACEs in adolescence is unclear, and understanding how ACEs relate to blood pressure (BP) and vascular function during early life is key for the development of prevention strategies to reduce CVD risk. We hypothesized that exposure to ACEs would be associated with changes in central hemodynamics such as increased vascular stiffness and higher BP during adolescence. Methods This pilot study enrolled 86 adolescents recruited from the Children's of Alabama. A validated ACE questionnaire was employed, and ACEs were modeled both as a continuous variable and a categorical variable (ACE [greater than or equal to] 1 vs. ACE = 0). The primary outcomes used are considered to be indicators of future cardio-renal disease risk: aortic augmentation index normalized to 75 bpm (Alx75, a surrogate for vascular stiffness), carotid-femoral PWV (m/s), and ambulatory BP patterns. Results Adolescents with ACE [greater than or equal to] 1 had significantly higher Alx75 (ACE: 5.2% ± 2.2 compared to no ACE: - 1.4% ± 3.0; p = 0.043). PWV only reflected this trend when adjustments were made for the body mass index. Adolescents with ACEs showed no differences in ambulatory BP patterns during the 24-h, wake, or sleep periods compared to adolescents with no ACEs. Conclusions ACEs were associated with higher AIx75 in adolescence, which is a risk factor for future CVD. Adolescence could present an opportunity for early detections/interventions to mitigate adverse cardiovascular outcomes in adulthood. Graphical abstract

Belatacept is an intravenously infused selective T cell costimulation blocker approved for preventing organ rejection in renal transplant recipients aged ≥18 years. This phase I trial examined the pharmacokinetics and pharmacodynamics (percentage CD86 receptor occupancy [%CD86RO]) of a single dose of belatacept (7.5 mg/kg) administered to kidney transplant recipients aged 12-17 years receiving a stable calcineurin inhibitor-based immunosuppressive regimen. Nine adolescents (mean age 15.1 years) who were seropositive for Epstein-Barr virus were enrolled; all completed the 6-month study. Pharmacokinetics suggested relatively low variability of exposure (coefficients of variation for maximum observed serum concentration [Cmax ] and area under the serum concentration-time curve from time zero extrapolated to infinity [AUC0-INF ] were 20% and 25%, respectively). Mean half-life (T1/2 ) occurred 7.2 days postinfusion. Belatacept total body clearance was 0.48 mL/h/kg, and volume of distribution at steady-state (Vss ) was low at 0.09 L/kg. Compared with historical data from healthy adult volunteers administered a single dose of belatacept 10 mg/kg and adult kidney transplant recipients administered multiple doses of belatacept 5 mg/kg, pharmacokinetic values for adolescents were similar, indicating consistency across adolescent and adult populations. Mean %CD86RO increased with increasing belatacept concentration, indicating a direct relationship between pharmacokinetics and pharmacodynamics. Four patients reported 7 serious adverse events; none was considered related to belatacept. These data will inform belatacept dose selection in future studies of adolescent kidney transplant recipients.

Author(s): Erica C. Bjornstad [sup.1] , Michael E. Seifert [sup.1] , Keia Sanderson [sup.2] , Daniel I. Feig [sup.1] Author Affiliations: (1) grid.265892.2, 0000000106344187, Department of Pediatrics, Nephrology, University of [...], Research indicates that severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) infection can impact every organ, and the effects can range from asymptomatic to severe disease. Since it was first discovered in December 2019, our understanding has grown about its impact on kidney disease. In general, children have less severe disease than adults, and this tendency appears to extend to special pediatric kidney populations (e.g., chronic kidney disease and immunosuppressed patients with solid organ transplants or nephrotic syndrome). However, in a fraction of infected children, SARS-CoV2 causes an array of kidney manifestations, ranging from acute kidney injury to thrombotic microangiopathy, with potential implications for increased risk of morbidity and mortality. Additional considerations surround the propensity for clotting extracorporeal circuits in children with SARS-CoV2 infection that are receiving kidney replacement therapy. This review provides an update on our current understanding of SARS-CoV2 for pediatric nephrologists and highlights knowledge gaps to be addressed by future research during this ongoing pandemic, particularly the social disparities magnified during this period.

Author(s): Jeffrey D. Lebensburger [sup.1] , Gary R. Cutter [sup.2] , Thomas H. Howard [sup.1] , Paul Muntner [sup.3] , Daniel I. Feig [sup.4] Author Affiliations: (1) Pediatric Hematology and [...], Background Patients with sickle cell anemia (SCA) have an increased prevalence of nephropathy and mortality from chronic kidney disease (CKD). Methods We evaluated the association of hyperuricemia and nocturnal hypertension with lower estimated glomerular filtration rate (eGFR) using cystatin-C in patients aged 10-21 years with the HbSS or HbSB0 form of the disease during a non-acute clinic visit. eGFR and uric acid measurements were obtained in 83 and 81 participants, respectively, and 24-h ambulatory blood pressure monitoring (ABPM) was performed in 44 participants. Annual testing included vital signs, complete blood count, comprehensive metabolic panel, medications, urine microalbumin/creatinine, and lactate dehydrogenase measurements. Hyperuricemia was defined as a uric acid level of [greater than or equal to]5.5 mg/dL. Nocturnal hypertension was defined as >25% of nocturnal readings at >95th percentile according to norms established by the American Heart Association Statement on ABPM in children and adolescents. Results The mean eGFR was statistically significantly lower in patients with hyperuricemia than in those with normal uric acid levels (143 vs. 161 mL/min/1.73 m.sup.2, respectively). Of the 44 participants for whom ABPM data were available, 14 (32%) had systolic nocturnal hypertension and 12 (27%) had diastolic nocturnal hypertension. The mean eGFR was statistically significantly lower in participants with nocturnal systolic and diastolic hypertension than in those with normal nocturnal blood pressure. In a regression model, nocturnal hypertension and hyperuricemia were associated with a lower eGFR. Conclusions Two risk factors for CKD, i.e., nocturnal hypertension and hyperuricemia, were associated with lower eGFR in older children and adolescent patients with SCA. Long-term studies on their association with progression to CKD in this population are warranted. Key point Nocturnal hypertension and hyperuricemia are established risk factors for nephropathy in other diseases and may play a role in SCA nephropathy.

Author(s): Jeffrey D. Lebensburger[sup.1] , Prasannalaxmi Palabindela[sup.1] , Thomas H. Howard[sup.1] , Daniel I. Feig[sup.2] , Inmaculada Aban[sup.3] , David J. Askenazi[sup.2] Author Affiliations: (1) Pediatric Hematology Oncology, University of [...], Background Patients with sickle cell disease are at risk for developing chronic kidney disease (CKD). Acute kidney injury (AKI) has been linked to progression to CKD, but limited data exist to determine its role in acute complications of sickle cell disease. We hypothesized that AKI occurs in pediatric patients admitted for acute chest syndrome (ACS) and prolongs hospitalization. Methods We conducted a 6-year retrospective review of pediatric patients with ACS admitted to a single medical institution. Results Of the 149 pediatric patients admitted for ACS during the 6-year study period, 12 (8 %) developed AKI. Comparison of patients with and without AKI revealed a significant association between AKI and a larger drop in hemoglobin value from baseline (2.7 vs. 1.4 g/dL; p = 0.003), a lower hemoglobin value at admission (6.4 vs. 7.5 g/dL; p = 0.03), and an increased white blood cell count at admission (33.1 vs. 19.8 x 10.sup.9/L; p < 0.0001), respectively. AKI (p < 0.0001) together with need for advanced respiratory support (biphasic positive airway pressure or mechanical ventilation) (p < 0.0001) and need for exchange transfusion (p < 0.0001) were associated with prolonged hospitalization. Conclusions Clinicians should monitor pediatric patients hospitalized for ACS for the development of AKI as a potentially modifiable risk factor for prolonged hospitalization.

Despite its discovery more than 150 years ago, the cause of primary hypertension remains unknown. Most studies suggest that hypertension involves genetic, congenital or acquired risk factors that result in a relative inability of the kidney to excrete salt (sodium chloride) in the kidneys. Here we review recent studies that suggest there may be two phases, with an initial phase driven by renal vasoconstriction that causes low-grade ischemia to the kidney, followed by the infiltration of immune cells that leads to a local autoimmune reaction that maintains the renal vasoconstriction. Evidence suggests that multiple mechanisms could trigger the initial renal vasoconstriction, but one way may involve fructose that is provided in the diet (such as from table sugar or high fructose corn syrup) or produced endogenously. The fructose metabolism increases intracellular uric acid, which recruits NADPH oxidase to the mitochondria while inhibiting AMP-activated protein kinase. A drop in intracellular ATP level occurs, triggering a survival response. Leptin levels rise, triggering activation of the sympathetic central nervous system, while vasopressin levels rise, causing vasoconstriction in its own right and stimulating aldosterone production via the vasopressin 1b receptor. Low-grade renal injury and autoimmune-mediated inflammation occur. High-salt diets can amplify this process by raising osmolality and triggering more fructose production. Thus, primary hypertension may result from the overactivation of a survival response triggered by fructose metabolism. Restricting salt and sugar and hydrating with ample water may be helpful in the prevention of primary hypertension. [ABSTRACT FROM AUTHOR]

The article discusses several studies relating to uric acid and its link to an increased risk of cardiovascular disease, hypertension and renal disease. It highlights the need for further testing to actually prove the connection between excessive uric acid and an increased risk of cardiovascular disease.

A study was conducted to determine whether lowering uric acid results in lowering blood pressure (BP) amongst hyperuricemic adolescents who have recently been diagnosed with hypertension. Results revealed that treatment with allopurinol resulted in reduced BP and suggest further research.

The worldwide epidemic of metabolic syndrome correlates with an elevation in serum uric acid as well as a marked increase in total fructose intake (in the form of table sugar and high-fructose corn syrup). Fructose raises uric acid, and the latter inhibits nitric oxide bioavailability. Because insulin requires nitric oxide to stimulate glucose uptake, we hypothesized that fructose-induced hyperuricemia may have a pathogenic role in metabolic syndrome. Four sets of experiments were performed. First, pair-feeding studies showed that fructose, and not dextrose, induced features (hyperinsulinemia, hypertriglyceridemia, and hyperuricemia) of metabolic syndrome. Second, in rats receiving a high-fructose diet, the lowering of uric acid with either allopurinol (a xanthine oxidase inhibitor) or benzbromarone (a uricosuric agent) was able to prevent or reverse features of metabolic syndrome. In particular, the administration of allopurinol prophylactically prevented fructose-induced hyperinsulinemia (272.3 vs.160.8 pmol/l, P < 0.05), systolic hypertension (142 vs. 133 mmHg, P < 0.05), hypertriglyceridemia (233.7 vs. 65.4 mg/dl, P < 0.01), and weight gain (455 vs. 425 g, P < 0.05) at 8 wk. Neither allopurinol nor benzbromarone affected dietary intake of control diet in rats. Finally, uric acid dose dependently inhibited endothelial function as manifested by a reduced vasodilatory response of aortic artery rings to acetylcholine. These data provide the first evidence that uric acid may be a cause of metabolic syndrome, possibly due to its ability to inhibit endothelial function. Fructose may have a major role in the epidemic of metabolic syndrome and obesity due to its ability to raise uric acid. obesity; insulin resistance

Because of its availability, carbamazepine is a drug commonly involved in accidental and intentional overdoses. Carbamazepine, approved by the Food and Drug Administration in 1968, is indicated as first-line therapy [...], Carbamazepine intoxication is common in the pediatric population. Highly protein-bound, carbamazepine is not removed efficiently through conventional hemodialysis. We describe the use of albumin-enhanced continuous venovenous hemodialysis (CVVHD) in a 10-year-old girl who developed coma and respiratory depression due to an intentional carbamazepine overdose (peak drug level of 44.8 µg/ml; therapeutic range: 8-12 µg/ml). Without intervention, the half-life of drug elimination is 25 to 60 hours in patients who are naive to carbamazepine and 12 to 20 hours in children on chronic carbamazepine therapy. In contrast, with albumin-enhanced CVVHD, we observed a half-life of 7 to 8 hours. The patient recovered rapidly and was discharged from hospital

Objective: To determine whether serum urate reduction with allopurinol lowers blood pressure (BP) in young adults and the mechanisms mediating this hypothesized effect. Methods: We conducted a single‐center, randomized, double‐blind, crossover clinical trial. Adults ages 18–40 years with baseline systolic BP ≥120 and <160 mm Hg or diastolic BP ≥80 and <100 mm Hg, and serum urate ≥5.0 mg/dl for men or ≥4.0 mg/dl for women were enrolled. Main exclusion criteria included chronic kidney disease, gout, or past use of urate‐lowering therapies. Participants received oral allopurinol (300 mg daily) or placebo for 1 month followed by a 2–4 week washout and then were crossed over. Study outcome measures were change in systolic BP from baseline, endothelial function estimated as flow‐mediated dilation (FMD), and high‐sensitivity C‐reactive protein (hsCRP) levels. Adverse events were assessed. Results: Ninety‐nine participants were randomized, and 82 completed all visits. The mean ± SD age was 28.0 ± 7.0 years, 62.6% were men, and 40.4% were African American. In the primary intent‐to‐treat analysis, systolic BP did not change during the allopurinol treatment phase (mean ± SEM −1.39 ± 1.16 mm Hg) or placebo treatment phase (−1.06 ± 1.08 mm Hg). FMD increased during allopurinol treatment periods compared to placebo treatment periods (mean ± SEM 2.5 ± 0.55% versus −0.1 ± 0.42%; P < 0.001). There were no changes in hsCRP level and no serious adverse events. Conclusion: Our findings indicate that urate‐lowering therapy with allopurinol does not lower systolic BP or hsCRP level in young adults when compared with placebo, despite improvements in FMD. These findings do not support urate lowering as a treatment for hypertension in young adults. [ABSTRACT FROM AUTHOR]

Hyperuricaemia is common among patients with chronic kidney disease (CKD), and increases in severity with the deterioration of kidney function. Although existing guidelines for CKD management do not recommend testing for or treatment of hyperuricaemia in the absence of a diagnosis of gout or urate nephrolithiasis, an emerging body of evidence supports a direct causal relationship between serum urate levels and the development of CKD. Here, we review randomized clinical trials that have evaluated the effect of urate-lowering therapy (ULT) on the rate of CKD progression. Among trials in which individuals in the control arm experienced progressive deterioration of kidney function (which we define as ≥4 ml/min/1.73 m² over the course of the study - typically 6 months to 2 years), treatment with ULT conferred consistent clinical benefits. In contrast, among trials where clinical progression was not observed in the control arm, treatment with ULT was ineffective, but this finding should not be used as an argument against the use of uric acid-lowering therapy. Although additional studies are needed to identify threshold values of serum urate for treatment initiation and to confirm optimal target levels, we believe that sufficient evidence exists to recommend routine measurement of serum urate levels in patients with CKD and consider initiation of ULT among those who are hyperuricaemic with evidence of deteriorating renal function, unless specific contraindications exist. [ABSTRACT FROM AUTHOR]

OBJECTIVE. Hypertension is common in the pediatric population. There is increasing evidence for early hypertensive target organ damage that may lead to substantial long-term morbidity. Because a critical aspect of [...]

The article discusses the main arguments against uric acid as a hypertension risk factor. Uric acid is considered by many as an antioxidant and has the ability to inactivate superoxide, single oxygen, and peroxynitrite. Its infusion in humans acutely enhances endothelial function. The enzyme reactions that create uric acid also produce oxidants. Lastly, the presence of genetic polymorphisms has been consistently shown to heighten the risk for gout but not for hypertension.