Purpose of review Renal proximal tubular sodium reabsorption is regulated by sodium transporters, including the sodium glucose transporter, sodium amino acid transporter, sodium hydrogen exchanger isoform 3 and sodium phosphate cotransporter type 2 located at the luminal/apical membrane, and sodium bicarbonate cotransporter and Na+/K+ATPase located at the basolateral membrane. This review summarizes recent studies on sodium transporters that play a major role in the increase in blood pressure in essential/polygenic hypertension. Recent findings Sodium transporters and Na+/K+ATPase are segregated in membrane lipid and nonlipid raft microdomains that regulate their activities and trafficking via cytoskeletal proteins. The increase in renal proximal tubule ion transport in polygenic hypertension is primarily due to increased activity of NHE3 and Cl/HCO3 exchanger at the luminal/apical membrane and a primary or secondary increase in Na+/K+ATPase activity. Summary The increase in renal proximal tubule ion transport in hypertension is due to increased actions by prohypertensive factors that are unopposed by antihypertensive factors.

BackgroundChildren are recognised as at lower risk of severe COVID-19 compared with adults, but the impact of immunosuppression is yet to be determined. This study aims to describe the clinical course of COVID-19 in children with kidney disease taking immunosuppressive medication and to assess disease severity.MethodsCross-sectional study hosted by the European Rare Kidney Disease Reference Network and supported by the European, Asian and International paediatric nephrology societies. Anonymised data were submitted online for any child (age <20 years) with COVID-19 taking immunosuppressive medication for a kidney condition. Study recruited for 16 weeks from 15 March 2020 to 05 July 2020. The primary outcome was severity of COVID-19.Results113 children were reported in this study from 30 different countries. Median age: 13 years (49% male). Main underlying reasons for immunosuppressive therapy: kidney transplant (47%), nephrotic syndrome (27%), systemic lupus erythematosus (10%). Immunosuppressive medications used include: glucocorticoids (76%), mycophenolate mofetil (MMF) (54%), tacrolimus/ciclosporine A (58%), rituximab/ofatumumab (11%). 78% required no respiratory support during COVID-19 illness, 5% required bi-level positive airway pressure or ventilation. Four children died; all deaths reported were from low-income countries with associated comorbidities. There was no significant difference in severity of COVID-19 based on gender, dialysis status, underlying kidney condition, and type or number of immunosuppressive medications.ConclusionsThis global study shows most children with a kidney disease taking immunosuppressive medication have mild disease with SARS-CoV-2 infection. We therefore suggest that children on immunosuppressive therapy should not be more strictly isolated than children who are not on immunosuppressive therapy.

Coronavirus disease of 2019 (COVID-19) is caused by severe acute respiratory syndrome, coronavirus 2 (SARS-CoV-2). Children with COVID-19 may present with respiratory symptoms far less frequently and the disease course also may be less severe as compared to adults. 1-3 Whether posttransplant patients on immunosuppression (IS) are at increased risk for severe COVID-19 is not very clear at this time. There are a few case reports of adult heart and renal transplant (RT) recipients with COVID-19 described recently. 4-6 However, the clinical course of COVID-19 in pediatric RT recipients remains largely unclear. Here, we report a 13-year-old male who acquired SARS-CoV-2 infection 5 years post-RT with excellent clinical outcome during a very short-term follow-up. To the best of our knowledge, we believe this to be one of the early reported cases of pediatric RT recipient with mild COVID-19 in the United States.

Objective To assess depression in children with chronic kidney disease (CKD) and to determine associations with patient characteristics, intellectual and educational levels, and health related quality of life (HRQoL). Study design Subjects aged 6–17 years from the Chronic Kidney Disease in Children cohort study completed the Children’s Depression Inventory (CDI), Wechsler’s Abbreviated Scales of Intelligence, Wechsler Individual Achievement Test-II-Abbreviated, and the Pediatric Inventory of Quality of Life Core Scales 4.0. Regression analyses determined associations of CDI score and depression status with subject characteristics, intellectual and educational levels, and HRQoL. A joint linear mixed model and Weibull model were used to determine the effects of CDI score on longitudinal changes in glomerular filtration rate (GFR) and time to renal replacement therapy. Results 344 subjects completed the CDI. Eighteen (5%) had elevated depressive symptoms and another 7 (2%) were being treated for depression. In adjusted analyses, maternal education beyond high school was associated with 5% lower CDI scores (estimate 0.95; 95% CI 0.92, 0.99). Depression status was associated with lower IQ (99 versus 88, P= 0.053), lower achievement (95 versus 77.5, P<0.05), and lower HRQoL by parent and child reports (effect estimates −15.48; 95% CI −28.71, −2.24 and −18.39; 95% CI −27.81, −8.96, respectively). CDI score was not related to change in GFR. Conclusion Children with depression had lower psychoeducational skills and worse HRQoL. Identifying and treating depression should be evaluated as a means to improve the academic performance and HRQoL of children with CKD.

CKD staged by level of eGFR and proteinuria characterizes the timeline of progression and can guide management strategies in children.