Acute kidney injury in children with chronic kidney disease is associated with faster decline in kidney function

Renal function in pediatric urologic surgical patients: Insight from the National Surgical Quality Improvement Program-Pediatric cohort

Background

Renal protection is a frequent indication for urological surgery in pediatric patients; however, preoperative assessment is not routinely performed. We assessed the rates of preoperative renal function testing and stratified outcomes after major pediatric urological surgery. Pediatric urology patients, specifically high-risk patients undergoing genitourinary surgeries, are likely to have an underdiagnosis of renal dysfunction after surgery.

Materials and methods

Cases were identified from the 2012 to 2019 National Surgical Quality Improvement Program-Pediatric database. Patients who underwent major urological surgery on an inpatient basis were included in this study. Abnormal renal function was defined as a creatinine (Cr) level of ≥0.5 mg/dL (younger than 2 years) and a glomerular filtration rate of <90 mL/min (2 years or older). Glomerular filtration rate was calculated using the bedside Schwartz equation (2 years or older): estimated glomerular filtration rate = 0.413 × (height/Cr).

Results

A total of 17,315 patients were included, of whom 3792 (21.9%) had documented Cr values. Based on the defined criteria, abnormal renal function was found in 7.3% of infants (younger than 2 years), 6.3% of children (2-9 years), and 15.0% of adolescents (10-18 years). Patients with abnormal preoperative renal function values were significantly (p < 0.001) more likely to experience readmission (10.2% vs. 5.8%), reoperation (3.7% vs. 1.6%), surgical organ/space infection (0.9% vs. 0.4%), transfusion (1.5% vs. 0.6%), renal insufficiency (1.6% vs. 0.4%), or urinary tract infection (5.1% vs. 3.6%).

Conclusions

In this pediatric population, 21.9% of the patients had documented preoperative Cr values before major urological surgery. Patients with documented abnormal preoperative renal function tests experienced higher complication rates. These patients have higher rates of progressive renal insufficiency and acute renal failure than those with normal renal function. The introduction of a standardized and unbiased risk assessment tool has the potential to offer patients benefits by pinpointing individuals with a heightened risk of complications. Further investigation is necessary to enhance the precise categorization of at-risk patients.

Framework for Kidney Health Follow-Up Among Neonates With Critical Cardiac Disease: A Report From the Neonatal Kidney Health Consensus Workshop

Acute kidney injury is common among neonates with critical cardiac disease. Risk factors and associations with kidney-related outcomes are heterogeneous and distinct from other neonates. As survival of children with critical cardiac disease increases to adulthood, the burden of chronic kidney disease is increasing. Thirty percent to 50% of adults with congenital heart disease have impaired kidney function, even in the absence of prior kidney injury episodes. This may be related to the current standardized acute kidney injury criteria, which may not fully capture clinically meaningful kidney injury and long-term kidney health risks. An improved understanding of which neonates with critical cardiac disease should undergo kidney health follow-up is imperative. During the National Institutes of Health-supported Neonatal Kidney Health Consensus Workshop to Address Kidney Health meeting conducted in February 2024, a panel of 51 neonatal nephrology experts focused on at-risk groups: (1) preterm infants, (2) critically ill infants with acute kidney injury, and (3) infants with critical cardiac disease. The critical cardiac disease subgroup, comprising multidisciplinary experts, used a modified Delphi process to achieve consensus on recommendations for kidney health follow-up. In this report, we review available data on kidney health follow-up in critical cardiac disease and summarize the 2 consensus-based recommendations. We introduce novel diagnostic and risk-stratification tools for acute kidney injury diagnosis in neonates with cardiac disease to guide follow-up recommendations. Finally, we identify important knowledge gaps, representing areas of focus for future research. These should be prioritized to understand and improve long-term kidney health in critical cardiac disease.

Lipid-lowering drugs and risk of rapid renal function decline: a mendelian randomization study

BACKGROUND

Chronic kidney disease (CKD) patients face the risk of rapid kidney function decline leading to adverse outcomes like dialysis and mortality. Lipid metabolism might contribute to acute kidney function decline in CKD patients. Here, we utilized the Mendelian Randomization approach to investigate potential causal relationships between drug target-mediated lipid phenotypes and rapid renal function decline.

METHODS

In this study, we utilized two methodologies: summarized data-based Mendelian randomization (SMR) and inverse variance-weighted Mendelian randomization (IVW-MR), to approximate exposure to lipid-lowering drugs. This entailed leveraging expression quantitative trait loci (eQTL) for drug target genes and genetic variants proximal to drug target gene regions, which encode proteins associated with low-density lipoprotein (LDL) cholesterol, as identified in genome-wide association studies. The objective was to investigate causal associations with the progression of rapid kidney function decline.

RESULTS

The SMR analysis revealed a potential association between high expression of PCSK9 and rapid kidney function decline (OR = 1.11, 95% CI= [1.001-1.23]; p = 0.044). Similarly, IVW-MR analysis demonstrated a negative association between LDL cholesterol mediated by HMGCR and kidney function decline (OR = 0.74, 95% CI = 0.60-0.90; p = 0.003).

CONCLUSION

Genetically predicted inhibition of HMGCR is linked with the progression of kidney function decline, while genetically predicted PCSK9 inhibition is negatively associated with kidney function decline. Future research should incorporate clinical trials to validate the relevance of PCSK9 in preventing kidney function decline.

Kidney disease progression in pediatric and adult posterior urethral valves (PUV) patients

BACKGROUND

Posterior urethral valves (PUV) is the most common cause of obstructive uropathy in boys; approximately 15% develop kidney failure by early adulthood. However, rates of kidney function decline are poorly defined in PUV children and adults, as is the impact of potentially modifiable chronic kidney disease (CKD) progression risk factors.

METHODS

We conducted a retrospective review of all PUV patients followed at our institution from 1995 to 2018. Inclusion criteria were estimated glomerular filtration rate (eGFR) > 20 ml/min/1.73 m2 after 1 year of age, no dialysis or kidney transplant history, and ≥ 2 yearly serum creatinine values after age 1 year. eGFRs were calculated using creatinine-based estimating formulas for children (CKID U25) or adults (CKD-EPI). The primary outcome was annualized change in eGFR, assessed with linear mixed effects models. We also examined the association of acute kidney injury (AKI), proteinuria, hypertension (HTN), and recurrent febrile urinary tract infections (UTIs) with eGFR decline.

RESULTS

Fifty-two PUV patients met the inclusion criteria. Median (interquartile range) eGFR decline was 2.6 (2.1, 3.1) ml/min/1.73 m2/year. Children (n = 35) and adults (n = 17) demonstrated progressive decline. Proteinuria and recurrent UTIs were significantly associated with faster progression; AKI and HTN were also associated but did not reach significance.

CONCLUSION

PUV patients show progressive loss of kidney function well into adulthood. Proteinuria and recurrent UTIs are associated with faster progression, suggesting potential modifiable risk factors. This is the first study to report annualized eGFR decline rates in PUV patients, which could help inform the design of clinical trials of CKD therapies.

Evaluating Kidney Function Decline in Children with Chronic Kidney Disease Using a Multi-Institutional Electronic Health Record Database

BACKGROUND

The objectives of this study were to use electronic health record data from a US national multicenter pediatric network to identify a large cohort of children with CKD, evaluate CKD progression, and examine clinical risk factors for kidney function decline.

METHODS

This retrospective cohort study identified children seen between January 1, 2009, to February 28, 2022. Data were from six pediatric health systems in PEDSnet. We identified children aged 18 months to 18 years who met criteria for CKD: two eGFR values <90 and ≥15 ml/min per 1.73 m2 separated by ≥90 days without an intervening value ≥90. CKD progression was defined as a composite outcome: eGFR <15 ml/min per 1.73 m2, ≥50% eGFR decline, long-term dialysis, or kidney transplant. Subcohorts were defined based on CKD etiology: glomerular, nonglomerular, or malignancy. We assessed the association of hypertension (≥2 visits with hypertension diagnosis code) and proteinuria (≥1 urinalysis with ≥1+ protein) within 2 years of cohort entrance on the composite outcome.

RESULTS

Among 7,148,875 children, we identified 11,240 (15.7 per 10,000) with CKD (median age 11 years, 50% female). The median follow-up was 5.1 (interquartile range 2.8-8.3) years, the median initial eGFR was 75.3 (interquartile range 61-83) ml/min per 1.73 m2, 37% had proteinuria, and 35% had hypertension. The following were associated with CKD progression: lower eGFR category (adjusted hazard ratio [aHR] 1.44 [95% confidence interval (95% CI), 1.23 to 1.69], aHR 2.38 [95% CI, 2.02 to 2.79], aHR 5.75 [95% CI, 5.05 to 6.55] for eGFR 45-59 ml/min per 1.73 m2, 30-44 ml/min per 1.73 m2, 15-29 ml/min per 1.73 m2 at cohort entrance, respectively, when compared with eGFR 60-89 ml/min per 1.73 m2), glomerular disease (aHR 2.01 [95% CI, 1.78 to 2.28]), malignancy (aHR 1.79 [95% CI, 1.52 to 2.11]), proteinuria (aHR 2.23 [95% CI, 1.89 to 2.62]), hypertension (aHR 1.49 [95% CI, 1.22 to 1.82]), proteinuria and hypertension together (aHR 3.98 [95% CI, 3.40 to 4.68]), count of complex chronic comorbidities (aHR 1.07 [95% CI, 1.05 to 1.10] per additional comorbid body system), male sex (aHR 1.16 [95% CI, 1.05 to 1.28]), and younger age at cohort entrance (aHR 0.95 [95% CI, 0.94 to 0.96] per year older).

CONCLUSIONS

In large-scale real-world data for children with CKD, disease etiology, albuminuria, hypertension, age, male sex, lower eGFR, and greater medical complexity at start of follow-up were associated with more rapid decline in kidney function.