Association Between Urinary Biomarkers and CKD in Extremely Low Gestational Age Neonates.

RATIONALE & OBJECTIVE: Children born before 28 weeks' gestation are at increased risk of chronic kidney disease (CKD). Urine biomarkers may shed light on mechanistic pathways and improve the ability to forecast CKD. We evaluated whether urinary biomarkers in neonates of low gestational age (GA) are associated with a reduced estimated glomerular filtration rate (eGFR) over time. STUDY DESIGN: A cohort study of neonates with an exploratory case-control study of a subset of the cohort. SETTING & PARTICIPANTS: 327 neonates born at 24-27 weeks' gestation with 2-year eGFR data from the PENUT (Preterm Erythropoietin Neuroprotection Trial) and the REPaIReD (Recombinant Erythropoietin for Prevention of Infant Renal Disease) study. EXPOSURES: 11 urinary biomarkers measured at 27, 30, and 34 weeks' postmenstrual age for the primary cohort study and 10 additional biomarkers for the exploratory case-control study. OUTCOMES: eGFR<90mL/min/1.73m2 at 2 years corrected for GA. ANALYTICAL APPROACH: Linear mixed models to assess differences in biomarker values between neonates in whom CKD did and did not develop, accounting for multiple comparisons using Bonferroni-Holm correction in the cohort study only. Cohort analyses were adjusted for sex, GA, and body mass index. Cases were matched to controls on these variables in the case-control study. RESULTS: After adjusting for weeks of GA, urinary levels of α-glutathione-S-transferase (log difference, 0.27; 95% CI, 0.12-0.43), albumin (log difference, 0.13; 95% CI, 0.02-0.25), and cystatin C (log difference, 0.19; 95% CI, 0.04-0.34) were higher in those in whom CKD developed than in those in whom it did not. Urinary albumin and cystatin C levels did not remain significantly different after Bonferroni-Holm correction. In the exploratory case-control analysis, there were no differences in any biomarkers between cases and controls. LIMITATIONS: Early deaths and a high number of subjects without eGFR at 2 years corrected for GA. CONCLUSIONS: Measurement of urinary biomarkers may assist in monitoring neonates who are at risk for CKD. Additional studies are needed to confirm these findings. FUNDING: Grants from government (National Institutes of Health). TRIAL REGISTRATION: Registered at ClinicalTrials.gov with study number NCT01378273. PLAIN-LANGUAGE SUMMARY: Approximately 15 million neonates worldwide are born prematurely, and 2 million are born before 28 weeks' gestation. Many of these children go on to experience chronic kidney disease. Urine biomarkers may allow for early recognition of those at risk for the development of kidney disease. In this study of more than 300 children born before 28 weeks' gestational age, we found higher mean urinary levels of α-glutathione-S-transferase at 27, 30, and 34 weeks in children whose estimated glomerular filtration rate was<90mL/min/1.73m2 at 2 years compared with children whose estimated glomerular filtration rate was>90mL/min/1.73m2 at 2 years. Measurement of urinary biomarkers may assist in monitoring neonates who are at risk for chronic kidney disease. Additional studies are needed to confirm our findings.

A quantitative assessment of renal function utilizing albuminuria in pediatric heart transplant recipients.

INTRODUCTION: Kidney disease is common after pediatric heart transplantation. Serum creatinine-based glomerular filtration rate is the most frequently reported measure of kidney function. Albuminuria is an additional marker of kidney dysfunction and is not well described in this population. In this study, we evaluate the prevalence and degree of albuminuria and describe clinical factors associated with albuminuria in a cohort of pediatric heart transplant recipients. METHODS: This was a cross-sectional study of pediatric heart transplant recipients. Albuminuria was assessed using spot urine albumin-to-creatinine ratio collected at the most recent annual screening cardiac catheterization through August 2019. RESULTS: In 115 patients at a median duration of 10.2 years post-transplant, 39% had albuminuria. Stage 3 or greater chronic kidney disease was present in 6%. The immunosuppressive regimen at the time of measurement contained a calcineurin inhibitor (CNI) in 88% and a proliferation signal inhibitor (PSI) in 62%. In multivariable modeling, lower eGFR, PSI use, and younger age at transplant were associated with higher levels of albuminuria, whereas CNI use was associated with lower levels of albuminuria. CONCLUSION: Albuminuria is a prevalent finding in medium-term follow up of pediatric heart transplant recipients, reflecting kidney injury, and is associated with other markers of kidney dysfunction, such as low eGFR. Younger age at transplant, lower eGFR, and PSI use were among the associations with albuminuria.

Longitudinal analysis of blood pressure and lipids in childhood nephrotic syndrome.

BACKGROUND: In the current study, longitudinal BP and lipid measurements were examined in a NEPTUNE cohort of children with newly diagnosed nephrotic syndrome (cNEPTUNE). We hypothesized that hypertensive BP and dyslipidemia would persist in children with nephrotic syndrome, regardless of steroid treatment response. METHODS: A multi-center longitudinal observational analysis of data obtained from children < 19 years of age with new onset nephrotic syndrome enrolled in the Nephrotic Syndrome Study Network (cNEPTUNE) was conducted. BP and lipid data were examined over time stratified by disease activity and steroid exposure. Generalized estimating equation regressions were used to find determinants of hypertensive BP and dyslipidemia. RESULTS: Among 122 children, the prevalence of hypertensive BP at any visit ranged from 17.4% to 57.4%, while dyslipidemia prevalence ranged from 40.0% to 96.2% over a median of 30 months of follow-up. Hypertensive BP was found in 46.2% (116/251) of study visits during active disease compared with 31.0% (84/271) of visits while in remission. Dyslipidemia was present in 88.2% (120/136) of study visits during active disease and in 66.0% (101/153) while in remission. Neither dyslipidemia nor hypertensive BP were significantly different with/without medication exposure (steroids and/or CNI). In regression analysis, male sex and urine protein:creatinine ratio (UPC) were significant determinants of hypertensive BP over time, while eGFR was found to be a determinant of dyslipidemia over time. CONCLUSIONS: Results demonstrate persistent hypertensive BPs and unfavorable lipid profiles in the cNEPTUNE cohort regardless of remission status or concurrent steroid or calcineurin inhibitor treatment.

Growth in children with nephrotic syndrome: a post hoc analysis of the NEPTUNE study.

BACKGROUND: Steroids, the mainstay of treatment for nephrotic syndrome in children, have multiple adverse effects including growth suppression. METHODS: Anthropometric measurements in children < 18 years enrolled in the Nephrotic Syndrome Study Network (NEPTUNE) were collected. The longitudinal association of medication exposure and nephrotic syndrome characteristics with height z-score and growth velocity was determined using adjusted Generalized Estimating Equation regression and linear regression. RESULTS: A total of 318 children (57.2% males) with a baseline age of 7.64 ± 5.04 years were analyzed. The cumulative steroid dose was 216.4 (IQR 61.5, 652.7) mg/kg (N = 233). Overall, height z-scores were not significantly different at the last follow-up compared to baseline (- 0.13 ± 1.21 vs. - 0.23 ± 1.71, p = 0.21). In models adjusted for age, sex, and eGFR, greater cumulative steroid exposure (ß - 7.5 × 10-6, CI - 1.2 × 10-5, - 3 × 10-6, p = 0.001) and incident cases of NS (vs. prevalent) (ß - 1.1, CI - 2.22, - 0.11, p = 0.03) were significantly associated with lower height z-scores over time. Rituximab exposure was associated with higher height z-scores (ß 0.16, CI 0.04, 0.29, p = 0.01) over time. CONCLUSION: Steroid dose was associated with lower height z-score, while rituximab use was associated with higher height z-score.

Precision nephrology identified tumor necrosis factor activation variability in minimal change disease and focal segmental glomerulosclerosis.

The diagnosis of nephrotic syndrome relies on clinical presentation and descriptive patterns of injury on kidney biopsies, but not specific to underlying pathobiology. Consequently, there are variable rates of progression and response to therapy within diagnoses. Here, an unbiased transcriptomic-driven approach was used to identify molecular pathways which are shared by subgroups of patients with either minimal change disease (MCD) or focal segmental glomerulosclerosis (FSGS). Kidney tissue transcriptomic profile-based clustering identified three patient subgroups with shared molecular signatures across independent, North American, European, and African cohorts. One subgroup had significantly greater disease progression (Hazard Ratio 5.2) which persisted after adjusting for diagnosis and clinical measures (Hazard Ratio 3.8). Inclusion in this subgroup was retained even when clustering was limited to those with less than 25% interstitial fibrosis. The molecular profile of this subgroup was largely consistent with tumor necrosis factor (TNF) pathway activation. Two TNF pathway urine markers were identified, tissue inhibitor of metalloproteinases-1 (TIMP-1) and monocyte chemoattractant protein-1 (MCP-1), that could be used to predict an individual's TNF pathway activation score. Kidney organoids and single-nucleus RNA-sequencing of participant kidney biopsies, validated TNF-dependent increases in pathway activation score, transcript and protein levels of TIMP-1 and MCP-1, in resident kidney cells. Thus, molecular profiling identified a subgroup of patients with either MCD or FSGS who shared kidney TNF pathway activation and poor outcomes. A clinical trial testing targeted therapies in patients selected using urinary markers of TNF pathway activation is ongoing.

Premature infants born <28 weeks with acute kidney injury have increased bronchopulmonary dysplasia rates.

BACKGROUND: Despite a growing understanding of bronchopulmonary dysplasia (BPD) and advances in management, BPD rates remain stable. There is mounting evidence that BPD may be due to a systemic insult, such as acute kidney injury (AKI). Our hypothesis was that severe AKI would be associated with BPD. METHODS: We conducted a secondary analysis of premature infants [24-27 weeks gestation] in the Recombinant Erythropoietin for Protection of Infant Renal Disease cohort (N = 885). We evaluated the composite outcome of Grade 2/3 BPD or death using generalized estimating equations. In an exploratory analysis, urinary biomarkers of angiogenesis (ANG1, ANG2, EPO, PIGF, TIE2, FGF, and VEGFA/D) were analyzed. RESULTS: 594 (67.1%) of infants had the primary composite outcome of Grade 2/3 BPD or death. Infants with AKI (aOR: 1.69, 95% CI: 1.16-2.46) and severe AKI (aOR: 2.05, 95% CI: 1.19-3.54). had increased risk of the composite outcome after multivariable adjustment Among 106 infants with urinary biomarkers assessed, three biomarkers (VEGFA, VEGFD, and TIE2) had AUC > 0.60 to predict BPD. CONCLUSIONS: Infants with AKI had a higher likelihood of developing BPD/death, with the strongest relationship seen in those with more severe AKI. Three urinary biomarkers of angiogenesis may have potential to predict BPD development. IMPACT: AKI is associated with lung disease in extremely premature infants, and urinary biomarkers may predict this relationship. Infants with AKI and severe AKI have higher odds of BPD or death. Three urinary angiogenesis biomarkers are altered in infants that develop BPD. These findings have the potential to drive future work to better understand the mechanistic pathways of BPD, setting the framework for future interventions to decrease BPD rates. A better understanding of the mechanisms of BPD development and the role of AKI would have clinical care, cost, and quality of life implications given the long-term effects of BPD.

Urine acute kidney injury biomarkers in extremely low gestational age neonates: a nested case control study of 21 candidate urine biomarkers.

BACKGROUND: Acute kidney injury (AKI) is common and is associated with poor clinical outcomes in premature neonates. Urine biomarkers hold the promise to improve our understanding and care of patients with kidney disease. Because kidney maturation and gender can impact urine biomarker values in extremely low gestational age neonates (ELGANs), careful control of gestational age (GA) and time is critical to any urine biomarker studies in neonates. METHODS: To improve our understanding of the potential use of urine biomarkers to detect AKI during the first postnatal weeks, we performed a nested case-control study to evaluate 21 candidate urine AKI biomarkers. Cases include 20 ELGANs with severe AKI. Each case was matched with 2 controls for the same GA week (rounded down to the nearest week), gender, and birth weight (BW) (± 50 g). RESULTS: Urine cystatin C, creatinine, ghrelin, fibroblast growth factor-23 (FGF23), tissue metalloproteinase 2 (TIMP2) and vascular endothelial growth factor A (VEGFa) concentrations were higher in ELGANs with early severe AKI compared to matched control subjects without AKI. Urine epidermal growth factor (EGF) and uromodulin (UMOD) concentrations are lower in cases than controls. Interleukin (IL)-15 was lower on day 1, but higher on day 8 in cases than controls; while VEGFa was lower on day 1, but higher on day 5 in cases than controls. CONCLUSION: Urine biomarkers hold the promise to improve our ability to reliably detect kidney injury. Interventional studies are needed to determine the biomarkers' ability to predict outcomes, enhance AKI phenotypes, and improve timely interventions which can prevent the sequalae of AKI in ELGANs. A higher resolution version of the Graphical abstract is available as Supplementary information.

Risk factors for severe acute kidney injury after pediatric hematopoietic cell transplantation.

BACKGROUND: Acute kidney injury (AKI) is common after hematopoietic cell transplantation (HCT) and is associated with poorer outcomes. Risk factors for AKI after pediatric HCT are not fully understood. The study objective was to assess unique risk factors for AKI in the HCT population and evaluate post-HCT AKI patterns. METHODS: We conducted a retrospective cohort study of patients < 21 years of age who underwent HCT at Seattle Children's Hospital/Fred Hutchinson Cancer Center from September 2008 to July 2017 (n = 484). We defined AKI using KDIGO criteria. We collected demographics, baseline HCT characteristics, post-HCT complications, and mortality. Multinomial logistic regression was used to estimate association between AKI and potential risk factors. We used adjusted Cox proportional hazard ratios to evaluate differences in mortality. RESULTS: One hundred and eighty-six patients (38%) developed AKI. Seventy-nine (42%) had severe AKI and 27 (15%) required kidney replacement therapy. Fluid overload was common in all groups and 67% of those with severe AKI had > 10% fluid overload. Nephrology was consulted in less than 50% of those with severe AKI. In multivariable analysis, risk of severe AKI was lower in those taking a calcineurin inhibitor (CNI). Risk of death was higher in severe AKI compared to no AKI (RR 4.6, 95% CI 2.6-8.1). CONCLUSIONS: AKI and fluid overload are common in pediatric patients after HCT. Severe AKI occurred less often with CNI use and was associated with higher mortality. Future interventions to reduce AKI and its associated complications such as fluid overload are approaches to reducing morbidity and mortality after HCT. A higher resolution version of the Graphical abstract is available as Supplementary information.

The association of low birthweight and prematurity on outcomes in children and adults with nephrotic syndrome-a NEPTUNE cohort study.

BACKGROUND: In single-center studies, both preterm birth and low birth weight (LBW) are associated with worse outcomes in childhood nephrotic syndrome. Using the Nephrotic Syndrome Study Network (NEPTUNE) observational cohort, we tested the hypothesis that in patients with nephrotic syndrome, hypertension, proteinuria status, and disease progression would be more prevalent and more severe in subjects with LBW and prematurity singly or in combination (LBW/prematurity). METHODS: Three hundred fifty-nine adults and children with focal segmental glomerulosclerosis (FSGS) or minimal change disease (MCD) and available birth history were included. Estimated glomerular filtration rate (eGFR) decline and remission status were primary outcomes, and secondary outcomes were kidney histopathology, kidney gene expression, and urinary biomarkers. Logistic regression was used to identify associations with LBW/prematurity and these outcomes. RESULTS: We did not find an association between LBW/prematurity and remission of proteinuria. However, LBW/prematurity was associated with greater decline in eGFR. This decline in eGFR was partially explained by the association of LBW/prematurity with APOL1 high-risk alleles, but the association remained after adjustment. There were no differences in kidney histopathology or gene expression in the LBW/prematurity group compared to normal birth weight/term birth. CONCLUSION: LBW and premature babies who develop nephrotic syndrome have a more rapid decline in kidney function. We did not identify clinical or laboratory features that distinguished the groups. Additional studies in larger groups are needed to fully ascertain the effects of (LBW) and prematurity alone or in combination on kidney function in the setting of nephrotic syndrome.

Gestational age, sex, and time affect urine biomarker concentrations in extremely low gestational age neonates.

BACKGROUND: Our understanding of the normative concentrations of urine biomarkers in premature neonates is limited. METHODS: We evaluated urine from 750 extremely low gestational age (GA) neonates without severe acute kidney injury (AKI) to determine how GA affects ten different urine biomarkers at birth and over the first 30 postnatal days. Then, we investigated if the urine biomarkers changed over time at 27, 30, and 34 weeks postmenstrual age (PMA). Next, we evaluated the impact of sex on urine biomarker concentrations at birth and over time. Finally, we evaluated if urine biomarkers were impacted by treatment with erythropoietin (Epo). RESULTS: We found that all ten biomarker concentrations differ at birth by GA and that some urine biomarker concentrations increase, while others decrease over time. At 27 weeks PMA, 7/10 urine biomarkers differed by GA. By 30 weeks PMA, 5/10 differed, and by 34 weeks PMA, only osteopontin differed by GA. About half of the biomarker concentrations differed by sex, and 4/10 showed different rates of change over time between males vs. females. We found no differences in urine biomarkers by treatment group. CONCLUSIONS: The temporal patterns, GA, and sex differences need to be considered in urine AKI biomarker analyses. IMPACT: Urine biomarker concentrations differ by GA at birth. Some urine biomarkers increase, while others decrease, over the first 30 postnatal days. Most urine biomarkers differ by GA at 27 weeks PMA, but are similar by 34 weeks PMA. Some urine biomarkers vary by sex in premature neonates. Urine biomarkers did not differ between neonates randomized to placebo vs. Epo.

Determinants of medication adherence in childhood nephrotic syndrome and associations of adherence with clinical outcomes.

BACKGROUND: Pediatric patients with nephrotic syndrome take medications long-term with significant toxicity and complex regimens, yet data on medication adherence are limited. METHODS: In a multicenter observational study of patients with nephrotic syndrome, NEPTUNE (NCT01209000), we surveyed caregivers of patients <19 years old and adolescent patients on medication adherence during longitudinal follow-up beginning in June 2015. Data extraction was in October 2020. We described the proportion of nonadherent patients at first survey. Participant social and economic factors, condition-related factors, therapy-related factors, and patient-related factors were examined for relationships with nonadherence by generalized linear mixed models using the longitudinal data. In exploratory fashion, we assessed the relationship between adherence and subsequent steroid response classification by binary logistic regression and adherence with healthcare utilization by Poisson regression. RESULTS: A total of 225 participants completed a median of 3 surveys during follow-up (IQR, 2-5), with a total of 743 surveys. Overall, 80 (36%) reported nonadherence with medications. In adjusted analysis, older age (per 1 year; OR 1.08; 95% CI, 1.03 1.12), lower maternal educational level (≥ high school vs. < high school; OR 0.47; 95% CI 0.25 to 0.89), and increased parent and self-identification of medications barriers (per 1 point; OR 1.57; 95% CI, 1.15-2.15) were significantly associated with nonadherence. No relationship between nonadherence and subsequent frequency of healthcare utilization was observed. A trend toward increased subsequent steroid resistance classification was seen with nonadherence, though not statistically significant. CONCLUSIONS: Medication nonadherence is common in pediatric nephrotic syndrome. Investigations into the use of surveys in the clinic setting to identify at-risk patients and ways to support families over time are needed. A higher resolution version of the Graphical abstract is available as Supplementary information.

Food insecurity during COVID-19 in children with end-stage kidney disease: a pilot study.

BACKGROUND: Food insecurity, an important social determinant of health among children, has become more common during the COVID-19 pandemic. Children with chronic diseases including end-stage kidney disease (ESKD) are at higher risk of food insecurity due to their complex care needs, medication burden, and dietary restrictions. No data exists describing food insecurity prevalence in pediatric ESKD patients during the COVID-19 pandemic. METHODS: Food insecurity was assessed among families of children (age 0-18 years) with ESKD on chronic dialysis at two pediatric academic medical centers. Families were screened in April 2020 using the Hunger Vital Sign, a validated 2-question screening tool. We assessed impact of COVID-19 on food insecurity. We compared serum phosphorus "pre-COVID" (January/February 2020) to "during COVID" (April/May 2020). RESULTS: A total of 29 families enrolled in this study. 62% (18/29) of children with ESKD lived in food insecure households, and of those, 72% (13/18) reported that COVID-19 had worsened their food insecurity status. During the COVID-19 pandemic, food insecure patients experienced greater rise in their serum phosphorus levels (1.1 mg/dL vs. 0 mg/dL, p = 0.03) and decreased likelihood of having adequate phosphorus control (50% vs. 11%, p = 0.03). CONCLUSION: Food insecurity was common among children with ESKD on chronic dialysis during the COVID-19 pandemic. Children with food insecurity had a greater increase in their phosphorus levels during the pandemic than did food secure children. Further exploration into how food resources such as an onsite food pantry impacts food insecurity and phosphorus control in children with ESKD is essential.

The Impact of Erythropoietin on Short- and Long-Term Kidney-Related Outcomes in Neonates of Extremely Low Gestational Age. Results of a Multicenter, Double-Blind, Placebo-Controlled Randomized Clinical Trial.

OBJECTIVE: To evaluate whether extremely low gestational age neonates (ELGANs) randomized to erythropoietin have better or worse kidney-related outcomes during hospitalization and at 22-26 months of corrected gestational age (cGA) compared with those randomized to placebo. STUDY DESIGN: We performed an ancillary study to a multicenter double-blind, placebo-controlled randomized clinical trial of erythropoietin in ELGANs. RESULTS: The prevalence of severe (stage 2 or 3) acute kidney injury (AKI) was 18.2%. We did not find a statistically significant difference between those randomized to erythropoietin vs placebo for in-hospital primary (severe AKI) or secondary outcomes (any AKI and serum creatinine/cystatin C values at days 0, 7, 9, and 14). At 22-26 months of cGA, 16% of the cohort had an estimated glomerular filtration rate (eGFR) <90 mL/min/1.73 m2, 35.8% had urine albumin/creatinine ratio >30 mg/g, 23% had a systolic blood pressure (SBP) >95th percentile for age, and 40% had a diastolic blood pressure (DBP) >95th percentile for age. SBP >90th percentile occurred less often among recipients of erythropoietin (P < .04). This association remained even after controlling for gestational age, site, and sibship (aOR 0.6; 95% CI 0.39-0.92). We did not find statistically significant differences between treatment groups in eGFR, albumin/creatinine ratio, rates of SBP >95th percentile, or DBP >90th or >95th percentiles at the 2 year follow-up visit. CONCLUSIONS: ELGANs have high rates of in-hospital AKI and kidney-related problems at 22-26 months of cGA. Recombinant erythropoietin may protect ELGANs against long-term elevated SBP but does not appear to protect from AKI, low eGFR, albuminuria, or elevated DBP at 22-26 months of cGA.

Outcomes of kidney injury including dialysis and kidney transplantation in pediatric oncology and hematopoietic cell transplant patients.

Pediatric oncology and hematopoietic cell transplant (HCT) patients are susceptible to both acute kidney injury (AKI) and chronic kidney disease (CKD). The etiologies of AKI vary but include tumor infiltration, radiation, drug-induced toxicity, and fluid and electrolyte abnormalities including tumor lysis syndrome. HCT patients can also have additional complications such as sinusoidal obstructive syndrome, graft-versus-host disease, or thrombotic microangiopathy. For patients with severe AKI requiring dialysis, multiple modalities can be used successfully, although continuous kidney replacement therapy (CKRT) is often the principal modality for critically ill patients. While increasing numbers of pediatric cancer and HCT patients are now surviving long term, they remain at risk for a number of chronic medical conditions, including CKD. Certain high-risk patients, due to underlying risk factors or treatment-related complications, eventually develop kidney failure and may require kidney replacement therapies. Management of co-morbidities and complications associated with kidney failure, including use of erythropoietin for anemia and potential need for ongoing cancer-related treatment while on dialysis, is an additional consideration in this patient population. Kidney transplantation can be successfully performed in pediatric cancer survivors, although additional features such as specific cancer diagnosis and duration of remission should be considered.

APOL1 genotype-associated morphologic changes among patients with focal segmental glomerulosclerosis.

BACKGROUND: The G1 and G2 alleles of apolipoprotein L1 (APOL1) are common in the Black population and associated with increased risk of focal segmental glomerulosclerosis (FSGS). The molecular mechanisms linking APOL1 risk variants with FSGS are not clearly understood, and APOL1's natural absence in laboratory animals makes studying its pathobiology challenging. METHODS: In a cohort of 90 Black patients with either FSGS or minimal change disease (MCD) enrolled in the Nephrotic Syndrome Study Network (58% pediatric onset), we used kidney biopsy traits as an intermediate outcome to help illuminate tissue-based consequences of APOL1 risk variants and expression. We tested associations between APOL1 risk alleles or glomerular APOL1 mRNA expression and 83 light- or electron-microscopy traits measuring structural and cellular kidney changes. RESULTS: Under both recessive and dominant models in the FSGS patient subgroup (61%), APOL1 risk variants were significantly correlated (defined as FDR <0.1) with decreased global mesangial hypercellularity, decreased condensation of cytoskeleton, and increased tubular microcysts. No significant correlations were detected in MCD cohort. Independent of risk alleles, glomerular APOL1 expression in FSGS patients was not correlated with morphologic features. CONCLUSIONS: While APOL1-associated FSGS is associated with two risk alleles, both one and two risk alleles are associated with cellular/tissue changes in this study of FSGS patients. Our lack of discovery of a large group of tissue differences in FSGS and no significant difference in MCD may be due to the lack of power but also supports investigating whether machine learning methods may more sensitively detect APOL1-associated changes.

Survival, Nonrelapse Mortality, and Relapse-Related Mortality After Allogeneic Hematopoietic Cell Transplantation: Comparing 2003-2007 Versus 2013-2017 Cohorts.

Background: Allogeneic hematopoietic cell transplantation is indicated for refractory hematologic cancer and some nonmalignant disorders. Survival is limited by recurrent cancer and organ toxicity. Objective: To determine whether survival has improved over the past decade and note impediments to better outcomes. Design: The authors compared cohorts that had transplants during 2003 to 2007 versus 2013 to 2017. Survival outcome measures were analyzed, along with transplant-related complications. Setting: A center performing allogeneic transplant procedures. Participants: All recipients of a first allogeneic transplant during 2003 to 2007 and 2013 to 2017. Intervention: Patients received a conditioning regimen, infusion of donor hematopoietic cells, then immunosuppressive drugs and antimicrobial approaches to infection control. Measurements: Day-200 nonrelapse mortality (NRM), recurrence or progression of cancer, relapse-related mortality, and overall mortality, adjusted for comorbidity scores, source of donor cells, donor type, patient age, disease severity, conditioning regimen, patient and donor sex, and cytomegalovirus serostatus. Results: During the 2003-to-2007 and 2013-to-2017 periods, 1148 and 1131 patients, respectively, received their first transplant. Over the decade, decreases were seen in the adjusted hazards of day-200 NRM (hazard ratio [HR], 0.66 [95% CI, 0.48 to 0.89]), relapse of cancer (HR, 0.76 [CI, 0.61 to 0.94]), relapse-related mortality (HR, 0.69 [CI, 0.54 to 0.87]), and overall mortality (HR, 0.66 [CI, 0.56 to 0.78]). The degree of reduction in overall mortality was similar for patients who received myeloablative versus reduced-intensity conditioning, as well as for patients whose allograft came from a matched sibling versus an unrelated donor. Reductions were also seen in the frequency of jaundice, renal insufficiency, mechanical ventilation, high-level cytomegalovirus viremia, gram-negative bacteremia, invasive mold infection, acute and chronic graft-versus-host disease, and prednisone exposure. Limitation: Cohort studies cannot determine causality, and current disease severity criteria were not available for patients in the 2003-to-2007 cohort. Conclusion: Improvement in survival and reduction in complications were substantial after allogeneic transplant. Relapse of cancer remains the largest obstacle to better survival outcomes. Primary Funding Source: National Institutes of Health.

Prevalence of acute kidney injury (AKI) in extremely low gestational age neonates (ELGAN).

BACKGROUND: To determine the prevalence and severity of acute kidney injury (AKI) at different time frames in relation to gestational age (GA) and birthweight (BW) in extremely low gestational age neonates (ELGAN). Our hypothesis is that ELGAN with lower GA and lower BW have higher AKI rates. METHODS: A total of 923 ELGAN enrolled in the Preterm Erythropoietin Neuroprotection Trial were evaluated from birth until death or hospital discharge. AKI was defined according to kidney disease: improving global outcomes (KDIGO) definition from clinically-derived serum creatinine (SCr) measurements. Severe AKI was defined as stage 2 or higher. RESULTS: For the entire cohort, 351/923 (38.0%, CI = 34.8-41.3%) had at least one episode of stage 1 or higher AKI and 168/923 (18.2%, CI = 15.7-20.7%) had at least one episode of severe (stage 2 or higher) AKI. The prevalence of AKI stage 1 or higher for the entire cohort during the early (days 3-7), middle (days 8-14), and late follow-up period (after day 14) was 112/923 (12.1%, CI = 10.0-14.3%), 142/891 (15.9%, CI = 13.5-18.4%), and 249/875 (28.5%, CI = 25.4-31.5%), respectively. The rates of severe AKI during the hospital course were 27.8%, 21.9%, 13.6%, and 9.4% for the 24-, 25-, 26-, and 27-week GA groups, respectively. AKI rates were significantly higher with decreasing GA and decreasing BW for stated time trends (all p < 0.01 using tests for trend). CONCLUSIONS: AKI is relatively common in ELGAN during their initial hospital course and is associated with lower GA and BW.

Severe Acute Kidney Injury Is Associated With Increased Risk of Death and New Morbidity After Pediatric Septic Shock.

OBJECTIVES: Acute kidney injury is common in critically ill children; however, the frequency of septic shock-associated acute kidney injury and impact on functional status are unknown. We evaluated functional outcomes of children with septic shock-associated acute kidney injury. DESIGN: Secondary analysis of patients with septic shock from the prospective Life after Pediatric Sepsis Evaluation study. We defined acute kidney injury using Kidney Disease Improving Global Outcomes criteria, comparing patients with absent/Stage 1 acute kidney injury to those with Stage 2/3 acute kidney injury (severe acute kidney injury). Our primary outcome was a composite of mortality or new functional morbidity at day 28 of hospitalization or discharge. We also assessed poor long-term outcome, defined as mortality or a persistent, serious deterioration in health-related quality of life at 3 months. SETTING: Twelve academic PICUs in the United States. PATIENTS: Critically ill children, 1 month to 18 years, with community-acquired septic shock requiring vasoactive-inotropic support. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: More than 50% of patients (176/348) developed severe acute kidney injury; of those, 21.6% (38/176) required renal replacement therapy. Twice as many patients with severe acute kidney injury died or developed new substantive functional morbidity (38.6 vs 16.3%; p < 0.001). After adjustment for age, malignancy, and initial illness severity, severe acute kidney injury was independently associated with mortality or new substantive morbidity (adjusted odds ratio, 2.78; 95% CI, 1.63-4.81; p < 0.001). Children with severe acute kidney injury had poorer health-related quality of life at 3 months (adjusted effect size 2.46; 95% CI, 1.44-4.20; p = 0.002). Children with severe acute kidney injury required longer duration of mechanical ventilation (11.0 vs 7.0 d; p < 0.001) and PICU stay (11.7 vs 7.1 d; p < 0.001). CONCLUSIONS: Among children with septic shock, severe acute kidney injury was independently associated with increased risk of death or new substantive functional morbidity. Survivors of sepsis with severe acute kidney injury were more likely to have persistent, serious health-related quality of life deterioration at 3 months.

Acute Kidney Injury is Associated with Poor Lung Outcomes in Infants Born ≥32 Weeks of Gestational Age.

OBJECTIVE: This study aimed to evaluate the association between acute kidney injury (AKI) and lung outcomes in infants born ≥32 weeks of gestational age (GA). STUDY DESIGN: Secondary analysis of infants ≥32 weeks of GA in the assessment of worldwide acute kidney injury epidemiology in neonates (AWAKEN) retrospective cohort (n = 1,348). We used logistic regression to assess association between AKI and a composite outcome of chronic lung disease (CLD) or death at 28 days of age and linear regression to evaluate association between AKI and duration of respiratory support. RESULTS: CLD occurred in 82/1,348 (6.1%) infants, while death occurred in 22/1,348 (1.6%); the composite of CLD/death occurred in 104/1,348 (7.7%). Infants with AKI had an almost five-fold increased odds of CLD/death, which remained after controlling for GA, maternal polyhydramnios, multiple gestations, 5-minute Apgar's score, intubation, and hypoxic-ischemic encephalopathy (adjusted odds ratio [OR] = 4.9, 95% confidence interval [CI]: 3.2-7.4; p < 0.0001). Infants with AKI required longer duration of respiratory support (count ratio = 1.59, 95% CI: 1.14-2.23, p = 0.003) and oxygen (count ratio = 1.43, 95% CI: 1.22-1.68, p < 0.0001) compared with those without AKI. CONCLUSION: AKI is associated with CLD/death and longer duration of respiratory support in infants born at ≥32 weeks of GA. Further prospective studies are needed to elucidate the pathophysiologic relationship.

Acute Kidney Injury and Bronchopulmonary Dysplasia in Premature Neonates Born Less than 32 Weeks' Gestation.

OBJECTIVE: This study aimed to evaluate the association between acute kidney injury (AKI) and bronchopulmonary dysplasia (BPD) in infants born <32 weeks of gestational age (GA). STUDY DESIGN: Present study is a secondary analysis of premature infants born at <32 weeks of GA in the Assessment of Worldwide Acute Kidney Injury Epidemiology in Neonates (AWAKEN) retrospective cohort (n = 546). We stratified by gestational age and used logistic regression to determine association between AKI and moderate or severe BPD/mortality. RESULTS: Moderate or severe BPD occurred in 214 of 546 (39%) infants, while death occurred in 32 of 546 (6%); the composite of moderate or severe BPD/death occurred in 246 of 546 (45%). For infants born ≤29 weeks of gestation, the adjusted odds ratio (OR) of AKI and the primary outcome was 1.15 (95% confidence interval [CI] = 0.47-2.86; p = 0.76). Infants born between 29 and 32 weeks of gestation with AKI had four-fold higher odds of moderate or severe BPD/death that remained after controlling for multiple factors (adjusted OR = 4.21, 95% CI: 2.07-8.61; p < 0.001). CONCLUSION: Neonates born between 29 and 32 weeks who develop AKI had a higher likelihood of moderate or severe BPD/death than those without AKI. Further studies are needed to validate our findings and evaluate mechanisms of multiorgan injury.