Development and Validation of a Policy Tree Approach for Optimizing Intravenous Fluids in Critically Ill Patients with Sepsis and Acute Kidney Injury.

Purpose: Intravenous fluids are mainstay of management of acute kidney injury (AKI) after sepsis but can cause fluid overload. Recent literature shows that restrictive fluid strategy may be beneficial in some patients with AKI, however, identifying these patients is challenging. We aimed to develop and validate a machine learning algorithm to identify patients who would benefit from a restrictive fluid strategy. Methods: We included patients with sepsis who developed AKI within 48 hours of ICU admission and defined restrictive fluid strategy as receiving <500mL fluids within 24 hours after AKI. Our primary outcome was early AKI reversal within 48 hours of AKI onset, and secondary outcomes included sustained AKI reversal and major adverse kidney events (MAKE) at discharge. We used a causal forest, a machine learning algorithm to estimate individual treatment effects and policy tree algorithm to identify patients who would benefit by restrictive fluid strategy. We developed the algorithm in MIMIC-IV and validated it in eICU database. Results: Among 2,091 patients in the external validation cohort, policy tree recommended restrictive fluids for 88.2%. Among these, patients who received restrictive fluids demonstrated significantly higher rate of early AKI reversal (48.2% vs 39.6%, p<0.001), sustained AKI reversal (36.7% vs 27.4%, p<0.001) and lower rates of MAKE by discharge (29.3% vs 35.1%, p=0.019). These results were consistent in adjusted analysis. Conclusion: Policy tree based on causal machine learning can identify septic patients with AKI who benefit from a restrictive fluid strategy. This approach needs to be validated in prospective trials.

Machine learning derived serum creatinine trajectories in acute kidney injury in critically ill patients with sepsis.

BACKGROUND: Current classification for acute kidney injury (AKI) in critically ill patients with sepsis relies only on its severity-measured by maximum creatinine which overlooks inherent complexities and longitudinal evaluation of this heterogenous syndrome. The role of classification of AKI based on early creatinine trajectories is unclear. METHODS: This retrospective study identified patients with Sepsis-3 who developed AKI within 48-h of intensive care unit admission using Medical Information Mart for Intensive Care-IV database. We used latent class mixed modelling to identify early creatinine trajectory-based classes of AKI in critically ill patients with sepsis. Our primary outcome was development of acute kidney disease (AKD). Secondary outcomes were composite of AKD or all-cause in-hospital mortality by day 7, and AKD or all-cause in-hospital mortality by hospital discharge. We used multivariable regression to assess impact of creatinine trajectory-based classification on outcomes, and eICU database for external validation. RESULTS: Among 4197 patients with AKI in critically ill patients with sepsis, we identified eight creatinine trajectory-based classes with distinct characteristics. Compared to the class with transient AKI, the class that showed severe AKI with mild improvement but persistence had highest adjusted risks for developing AKD (OR 5.16; 95% CI 2.87-9.24) and composite 7-day outcome (HR 4.51; 95% CI 2.69-7.56). The class that demonstrated late mild AKI with persistence and worsening had highest risks for developing composite hospital discharge outcome (HR 2.04; 95% CI 1.41-2.94). These associations were similar on external validation. CONCLUSIONS: These 8 classes of AKI in critically ill patients with sepsis, stratified by early creatinine trajectories, were good predictors for key outcomes in patients with AKI in critically ill patients with sepsis independent of their AKI staging.

Impact of Using Blood Warmer During Continuous Kidney Replacement Therapy in Patients With Acute Kidney Injury.

PURPOSE: We investigated the impact of blood warmer use on hypotensive episodes in patients with acute kidney injury (AKI) receiving continuous kidney replacement therapy (CKRT). MATERIALS AND METHODS: We included patients with AKI undergoing CKRT between January 1, 2012, and January 1, 2021, at a tertiary academic hospital. Hypotensive episodes were defined as mean arterial pressure (MAP) <60 mm Hg or a decrease in MAP by ≥10 mm Hg, systolic blood pressure (SBP) < 90 mm Hg or a decrease in SBP by ≥20 mm Hg, or increased vasopressor requirement. These were analyzed by Poisson regression with repeated-measures analysis of variance using generalized estimation equation. RESULTS: There were 669 patients with AKI that required CKRT. Use of blood warmer on first day of CKRT was in 324 (48%) patients. Incidence rate ratio of hypotensive episodes during the first 24-h of CKRT in patients where a blood warmer was used was 1.06 (95% confidence interval [CI]: 0.98-1.13) compared to those where blood warmer was not used. This did not change in adjusted model. Overall, the within-subject effect of temperature on hypotensive episodes showed that higher temperature was associated with fewer episodes (0.94, 95% CI: 0.9-0.99 per 10 degrees increase, P = .007). CONCLUSION: Blood rewarming was not associated with hypotensive episodes during CKRT.

A Case Series of Median Arcuate Ligament Syndrome With Varied Presentations.

Median arcuate ligament syndrome (MALS) is characterized by the constriction of the celiac trunk caused by fibrous connections originating from the median arcuate ligament (MAL) and diaphragmatic crura. It presents with symptoms often leading to misdiagnosis. In this study, we present three cases of MALS, with distinct manifestations. These cases were diagnosed through comprehensive investigations and managed successfully using laparoscopic decompression. The diagnosis of MALS poses challenges due to its variable presentations and overlap with other conditions. Diagnostic imaging techniques such as Doppler ultrasound, computed tomography (CT) scans and angiography play a role in confirming the diagnosis. Laparoscopic decompression has proven to be a treatment option that relieves symptoms and restores blood flow. This series highlights the importance of considering MALS as a cause for abdominal pain cases. Early detection and the use of diagnostic techniques can result in favorable outcomes.

The association between polypharmacy and health-related quality of life among non-dialysis chronic kidney disease patients.

BACKGROUND AND OBJECTIVE: The United States government spends over $85 billion annually on treating non-dialysis chronic kidney disease (CKD). Patients with CKD are prescribed a multitude of medications to manage numerous comorbidities associated with CKD. Thus, this study aims to investigate the association between polypharmacy and health-related quality of life (HRQoL) in non-dialysis CKD patients. METHODS: This cross-sectional study utilized data from the Medical Expenditure Panel Survey (MEPS) from 2010 through 2019. We classified polypharmacy into three groups based on the number of medication classes: ≤ 4 (minor polypharmacy), 5 through 9 (major polypharmacy), and ≥ 10 (hyperpolypharmacy). To measure HRQoL, a Physical Component Summary (PCS) and a Mental Component Summary (MCS) were obtained from the 12-item Short-Form Health Survey version 2 and Veteran's Rand 12 item. We applied multivariable ordinary least squares regression to assess the association between polypharmacy and HRQoL in non-dialysis CKD patients. RESULTS: A total of 649 CKD patients (weighted n = 667,989) were included. Patients with minor polypharmacy, major polypharmacy, and hyperpolypharmacy were 22.27%, 48.24%, and 29.48%, respectively. Major polypharmacy and hyperpolypharmacy were significantly and negatively associated with lower PCS scores when compared with minor polypharmacy [Beta = -3.12 (95% CI: -3.62, -2.62), p-value<0.001; Beta = -4.13 (95CI: -4.74, -3.52), p-value<0.001]. Similarly, major polypharmacy and hyperpolypharmacy were significantly and negatively associated with lower MCS scores when compared to minor polypharmacy [Beta = -0.38 (95% CI: -0.55, -0.20), p-value<0.001; Beta = -1.70 (95% CI: -2.01, -1.40), p-value<0.001]. The top 5 classes of medications used by CKD patients were antihyperlipidemic (56.31%), beta-adrenergic blockers (49.71%), antidiabetics (42.14%), analgesics (42.17%), and diuretics (39.65%). CONCLUSION: Our study found that both major polypharmacy and hyperpolypharmacy were associated with lower HRQoL among non-dialysis CKD patients. This study highlights the need for further evaluation of the combination of medications taken by non-dialysis CKD patients to minimize unnecessary and inappropriate medication use.

Acceptance of Acute Kidney Injury Alert by Providers in Cardiac Surgery Intensive Care Unit.

BACKGROUND: Acute kidney injury (AKI) is a common complication after cardiac surgery and is associated with worse outcomes. Its management relies on early diagnosis, and therefore, electronic alerts have been used to alert clinicians for development of AKI. Electronic alerts are, however, associated with high rates of alert fatigue. OBJECTIVES: We designed this study to assess the acceptance of user-centered electronic AKI alert by clinicians. METHODS: We developed a user-centered electronic AKI alert that alerted clinicians of development of AKI in a persistent yet noninterruptive fashion. As the goal of the alert was to alert toward new or worsening AKI, it disappeared 48 hours after being activated. We assessed the acceptance of the alert using surveys at 6 and 12 months after the alert went live. RESULTS: At 6 months after their implementation, 38.9% providers reported that they would not have recognized AKI as early as they did without this alert. This number increased to 66.7% by 12 months of survey. Most providers also shared that they re-dosed or discontinued medications earlier, provided earlier management of volume status, avoided intravenous contrast use, and evaluated patients by using point-of-care ultrasounds more due to the alert. Overall, 83.3% respondents reported satisfaction with the electronic AKI alerts at 6 months and 94.4% at 12 months. CONCLUSION: This study showed high rates of acceptance of a user-centered electronic AKI alert over time by clinicians taking care of patients with AKI.

Echocardiographic parameters and hemodynamic instability at the initiation of continuous kidney replacement therapy.

OBJECTIVE: Investigate the association of echocardiographic parameters with hemodynamic instability after initiating continuous kidney replacement therapy (CKRT) in a cohort of intensive care unit (ICU) patients requiring CKRT. METHODS: Historical cohort study of consecutive adults admitted to the ICU at a tertiary care hospital from December 2006 through November 2015 who underwent CKRT and had an echocardiogram done within seven days before CKRT initiation. The primary outcome was hypotension within one hour of CKRT initiation. RESULTS: We included 980 patients, 804 (82%) with acute kidney injury (AKI) and 176 (18%) with end-stage kidney disease (ESKD). Median patient age was 63 (± 14) years, and median Sequential Organ Failure Assessment (SOFA) score on the day of CKRT initiation was 12 (IQR 10-14). Multivariable analysis showed that Left (OR 2.01, 95% CI 1.04-3.86), and Right (OR 1.5, 95% CI 1.04-2.25) moderate and severe ventricular enlargement, Vasoactive-Inotropic Score (VIS) one hour before CKRT initiation (OR 1.18 per 10 units increase, 95% CI 1.09-1.28) and high bicarbonate fluid replacement (OR 2.52, 95% CI 1.01-6.2) were associated with hypotension after CKRT initiation. CONCLUSION: Right and left ventricular enlargement are risk factors associated with hypotension after CKRT initiation.

Evaluating the Medication Regimen Complexity Score as a Predictor of Clinical Outcomes in the Critically Ill.

Background: Medication Regimen Complexity (MRC) refers to the combination of medication classes, dosages, and frequencies. The objective of this study was to examine the relationship between the scores of different MRC tools and the clinical outcomes. Methods: We conducted a retrospective cohort study at Roger William Medical Center, Providence, Rhode Island, which included 317 adult patients admitted to the intensive care unit (ICU) between 1 February 2020 and 30 August 2020. MRC was assessed using the MRC Index (MRCI) and MRC for the Intensive Care Unit (MRC-ICU). A multivariable logistic regression model was used to identify associations among MRC scores, clinical outcomes, and a logistic classifier to predict clinical outcomes. Results: Higher MRC scores were associated with increased mortality, a longer ICU length of stay (LOS), and the need for mechanical ventilation (MV). MRC-ICU scores at 24 h were significantly (p < 0.001) associated with increased ICU mortality, LOS, and MV, with ORs of 1.12 (95% CI: 1.06−1.19), 1.17 (1.1−1.24), and 1.21 (1.14−1.29), respectively. Mortality prediction was similar using both scoring tools (AUC: 0.88 [0.75−0.97] vs. 0.88 [0.76−0.97]. The model with 15 medication classes outperformed others in predicting the ICU LOS and the need for MV with AUCs of 0.82 (0.71−0.93) and 0.87 (0.77−0.96), respectively. Conclusion: Our results demonstrated that both MRC scores were associated with poorer clinical outcomes. The incorporation of MRC scores in real-time therapeutic decision making can aid clinicians to prescribe safer alternatives.

Association of serum potassium derangements with mortality among patients requiring continuous renal replacement therapy.

INTRODUCTION: We aimed to assess the association between serum potassium and mortality in patients receiving continuous renal replacement therapy (CRRT). METHODS: We studied 1279 acute kidney injury patients receiving CRRT in a tertiary referral hospital in the United States. We used logistic regression to assess the association of serum potassium before CRRT and mean serum potassium during CRRT with 90-day mortality after CRRT initiation, using serum potassium 4.0-4.4 mmol/L as reference group. RESULTS: Before CRRT, there was a U-shaped association between serum potassium and 90-day mortality. There was a significant increase in mortality when serum potassium before CRRT was ≤3.4 and ≥4.5 mmol/L. During CRRT, progressively increased mortality was noted when mean serum potassium was ≥4.5 mmol/L. The odds ratio of 90-day mortality was significantly higher when mean serum potassium was ≥4.5 mmol/L. CONCLUSION: Hypokalemia and hyperkalemia before CRRT and hyperkalemia during CRRT predicts 90-day mortality.

Prevalence of ANCA-associated vasculitis amid natural gas drilling sites in West Virginia.

BACKGROUND: The epidemiology of ANCA-associated vasculitis (AAV) varies by ethnicity and region. Environmental exposure has been implicated in the pathophysiology of MPO-AAV. The aim of this study was to evaluate the epidemiology of AAV and explore a potential relationship with environmental factors in north central West Virginia. METHODS: This is a retrospective cohort study of 212 patients diagnosed with AAV at West Virginia University and its affiliated hospitals from January 1, 1990 to December 31, 2019. We assessed prevalence of AAV over time according to patient's zip codes and counties. Silica exposure through natural gas extraction was considered as a possible environmental factor. RESULTS: The proportion of patients with MPO-ANCA increased after 2010 (37.5% before 2010 vs 61% after 2010, p = 0.008). At the same time, the prevalence of AAV in Monongalia and surrounding counties has increased significantly after 2010 from 64.8 to 141.9 cases per million (p = 0.001). The increase in prevalence of AAV was primarily due to an increase in MPO-AAV (43 vs 101.7 cases per million before and after 2010, respectively, p = 0.028). During this time, the production of natural gas through fracking increased, rising more than tenfold after 2010 (p-value < 0.001). Heat mapping reveals that the increase in cases of AAV occurred in areas of increased fracking activity. CONCLUSIONS: There was an increase in the prevalence of patients who were newly diagnosed with AAV over time in north central West Virginia. Further studies are required to ascertain the potential role of environmental exposure in the pathophysiology of AAV.

The Prognostic Importance of Serum Sodium for Mortality among Critically Ill Patients Requiring Continuous Renal Replacement Therapy.

BACKGROUND: Serum sodium derangement is common in critically ill patients requiring continuous renal replacement therapy (CRRT). We aimed to assess the association between serum sodium before and during CRRT with mortality. METHODS: This is a historical cohort study of 1,520 critically ill patients receiving CRRT from December 2006 through November 2015 in a tertiary hospital in the United States. Using logistic regression analysis, we used serum sodium before CRRT, mean serum sodium, and serum sodium changes during CRRT to predict 90-day mortality after CRRT initiation. RESULTS: Compared with the normal serum sodium levels, the odds ratio (OR) of 90-day mortality in patients with serum sodium before CRRT of 143-147 and ≥148 mmol/L were 1.45 (95% CI 1.03-2.05) and 2.24 (95% CI 1.33-3.87), respectively. There was no significant increase in 90-day mortality in serum sodium of ≤137 mmol/L. During CRRT, the mean serum sodium levels of ≤137 (OR 1.41; 95% CI 1.01-1.98) and ≥143 mmol/L (OR 1.52; 95% CI 1.14-2.03) were associated with higher 90-day mortality. The greater serum sodium changes during CRRT were associated with higher 90-mortality (OR 1.35; 95% CI 1.21-1.51 per 5-mmol/L increase). CONCLUSION: Before CRRT initiation, hypernatremia and during CRRT, hypo- and hypernatremia were associated with increased mortality.

Impact of chloride-rich crystalloids on sepsis-associated community-acquired acute kidney injury recovery in critically ill patients.

BACKGROUND: The use of chloride-rich crystalloids for resuscitation is associated with acute kidney injury (AKI). We aimed to explore the impact of resuscitation with chloride-rich crystalloids compared to balanced crystalloids on kidney function recovery in patients presenting with sepsis-associated community-acquired AKI (SACA-AKI). METHODS: This is a single-center, historical cohort study of the adult intensive care unit (ICU) patients who presented to the emergency department (ED) with  sepsis-associated community-acquired-AKI at the Mayo Clinic, Rochester, MN, from January 2011 to April 2018. We divided the cohort into two groups based on the primary type of crystalloids they received in the ED and the first 48-h of ICU. The first group received primarily normal saline with < 25% balanced solutions, and the second group received at least ≥ 25% balanced crystalloids during the initial volume resuscitation. RESULTS: Among the 732 enrolled patients [mean age: 64 ± 17, males: 461(63%)], 255 (35%) were in the second group and were found to have higher positive fluid balance during the first 48-h of admission compared to the first group [median + 2.3 (IQR: 0.4; 4.5) vs. + 1.1 (IQR: - 0.8; + 2.9) L, p < 0.001]. The second group had a higher rate of kidney function recovery by multivariate logistic regression after adjustments for known recovery risk factors (OR 1.46; 95% CI 1.05-2.04, p = 0.02). CONCLUSIONS: The use of balanced crystalloids during the initial resuscitation is associated with higher odds of kidney function recovery in AKI patients with sepsis-associated community-acquired AKI.

Prolonged exposure to continuous renal replacement therapy in patients with acute kidney injury.

BACKGROUND: Little is known about the process of deciding to discontinue continuous renal replacement therapy (CRRT) in patients with acute kidney injury (AKI) and the impact of CRRT duration on outcomes. METHODS: We report the clinical parameters of prolonged CRRT exposure and predictors of doubling of serum creatinine or need for dialysis at 90 days after CRRT with propensity score matching, including covariates that were likely to influence patients in the prolonged CRRT group. RESULTS: Among 104 survey responders, most use urine output (87%) to guide CRRT discontinuation, 24% use improvement in clinical or hemodynamic status. In the cohort study, of 854 included patients, 465 participated in the assessment of kidney recovery. Patients with prolonged CRRT had higher SOFA scores (11.9 vs. 11.2) and were more likely to be mechanically ventilated (99% vs. 84%) at CRRT initiation compared to patients without prolonged CRRT, p-value < 0.05. In multivariable logistic regression, daily urine output and cumulative fluid balance leading to CRRT discontinuation or day seven were independently associated with lower [OR 0.87 per 200 ml/day increase] and higher odds [OR 1.03 per 1-L increase] of requiring prolonged CRRT, respectively. After propensity score matching, prolonged exposure to CRRT was independently associated with increased risk of doubling serum creatinine or dialysis at 90 days, OR 3.1 (95% CI 1.23-8.3 p = 0.017). CONCLUSIONS: Resolution of critical illness and signs of kidney recovery are important factors when considering CRRT discontinuation. Prolonged CRRT exposure may be associated with less chance of kidney recovery among survivors.

Predicting acute kidney injury in critically ill patients using comorbid conditions utilizing machine learning.

BACKGROUND: Acute kidney injury (AKI) carries a poor prognosis. Its incidence is increasing in the intensive care unit (ICU). Our purpose in this study is to develop and externally validate a model for predicting AKI in the ICU using patient data present prior to ICU admission. METHODS: We used data of 98 472 adult ICU admissions at Mayo Clinic between 1 January 2005 and 31 December 2017 and 51 801 encounters from Medical Information Mart for Intensive Care III (MIMIC-III) cohort. A gradient-boosting model was trained on 80% of the Mayo Clinic cohort using a set of features to predict AKI acquired in the ICU. RESULTS: AKI was identified in 39 307 (39.9%) encounters in the Mayo Clinic cohort. Patients who developed AKI in the ICU were older and had higher ICU and in-hospital mortality compared to patients without AKI. A 30-feature model yielded an area under the receiver operating curve of 0.690 [95% confidence interval (CI) 0.682-0.697] in the Mayo Clinic cohort set and 0.656 (95% CI 0.648-0.664) in the MIMIC-III cohort. CONCLUSIONS: Using machine learning, AKI among ICU patients can be predicted using information available prior to admission. This model is independent of ICU information, making it valuable for stratifying patients at admission.

Antibody subtypes and titers predict clinical outcomes in ANCA-associated vasculitis.

The objective of this study is to evaluate the association between antineutrophil cytoplasmic autoantibody (ANCA) subtype and ANCA titers on clinical outcomes and disease activity among a cohort of patients from Central Appalachia diagnosed with ANCA-associated vasculitis (AAV) over a 3-decade period. This is a retrospective chart review of all patients diagnosed with AAV. ANCA subtypes (myeloperoxidase (MPO) and proteinase 3 (PR3)) and titers at the time of diagnosis and at the time of relapse or last follow-up were evaluated along with patient outcomes. Outcomes of interest included relapse, development of end-stage renal disease (ESRD) and mortality. Sensitivity analysis and multivariable analysis were performed. Of the 202 patients, 111 patients were MPO-ANCA positive and 91 patients were PR3-ANCA positive. Relapse was more frequent among patients with PR3-ANCA compared to MPO-ANCA (35% vs 12%, p < 0.001). In both ANCA subgroups, the strongest predictor of relapse was an increase in titers prior to relapse, HR 8.1 (95% CI 1.6-40), p 0.009. Patients who achieved serological remission had a lower risk of ESRD [sub-HR 0.31 (95% CI 0.11-0.89)] and mortality [HR (95% CI) 0.24 (0.07-0.7)]. PR3-ANCA was associated with higher risk of ESRD [sub-HR 3.1 (95% CI 1.1-8.5)]. There was no difference in mortality between patients with MPO-ANCA and PR3-ANCA. Our study supports the use of both ANCA subtypes and titer levels for predicting clinical outcomes in patients receiving treatment for AAV. Monitoring of ANCA antibody titers may be useful since both serological remission and increase in titers provide prognostic information.

Net ultrafiltration rate and its impact on mortality in patients with acute kidney injury receiving continuous renal replacement therapy.

BACKGROUND: Fluid overload, a critical consequence of acute kidney injury (AKI), is associated with worse outcomes. The optimal fluid removal rate per day during continuous renal replacement therapy (CRRT) is unknown. The purpose of this study is to evaluate the impact of the ultrafiltration rate on mortality in critically ill patients with AKI receiving CRRT. METHODS: This was a retrospective cohort study where we reviewed 1398 patients with AKI who received CRRT between December 2006 and November 2015 at the Mayo Clinic, Rochester, MN, USA. The net ultrafiltration rate (UFNET) was categorized into low- and high-intensity groups (<35 and ≥35 mL/kg/day, respectively). The impact of different UFNET intensities on 30-day mortality was assessed using logistic regression after adjusting for age, sex, body mass index, fluid balance from intensive care unit (ICU) admission to CRRT initiation, Acute Physiologic Assessment and Chronic Health Evaluation III and sequential organ failure assessment scores, baseline serum creatinine, ICU day at CRRT initiation, Charlson comorbidity index, CRRT duration and need of mechanical ventilation. RESULTS: The mean ± SD age was 62 ± 15 years, and 827 (59%) were male. There were 696 patients (49.7%) in the low- and 702 (50.2%) in the high-intensity group. Thirty-day mortality was 755 (54%). There were 420 (60%) deaths in the low-, and 335 (48%) in the high-intensity group (P < 0.001). UFNET ≥35 mL/kg/day remained independently associated with lower 30-day mortality (adjusted odds ratio = 0.47, 95% confidence interval 0.37-0.59; P < 0.001) compared with <35 mL/kg/day. CONCLUSIONS: More intensive fluid removal, UFNET ≥35 mL/kg/day, among AKI patients receiving CRRT is associated with lower mortality. Future prospective studies are required to confirm this finding.

The association of microhematuria with mesangial hypercellularity, endocapillary hypercellularity, crescent score and renal outcomes in immunoglobulin A nephropathy.

BACKGROUND: Microhematuria is common in immunoglobulin A nephropathy (IgAN). However, current prognostication is based on proteinuria and mesangial hypercellularity, endocapillary hypercellularity, segmental sclerosis, tubulointerstitial fibrosis and crescent (MEST-C) scores. METHODS: In this retrospective study, we evaluated whether MEST-C score components are associated with the presence of microhematuria at biopsy and whether the degree of microhematuria during follow-up is associated with change in estimated glomerular filtration rate (eGFR), after adjusting for clinical and histological parameters. We identified 125 patients with biopsy-proven IgAN and MEST-C scoring who were not on immunosuppressive therapy at biopsy. Microhematuria was defined as ≥3 red blood cells (RBCs)/high-power field (hpf). RESULTS: Of the 125 patients, 97 had microhematuria at baseline and were more likely to have M1, E1 and C ≥ 1 lesions (P < 0.05 for all) compared with patients without microhematuria. Of the 125 patients, 72 had follow-up data available. An increase in the degree of microhematuria was significantly associated with an eGFR decline of -0.81 mL/min/1.73 m2 [95% confidence interval (CI) -1.44 to -0.19, P = 0.01], after adjusting for follow-up time, proteinuria and T score. Severe microhematuria (≥21 RBCs/hpf) was associated with an even larger decline in eGFR (-3.99 mL/min/1.73 m2; 95% CI -6.9411 to -1.0552, P = 0.008), after similar adjustments. CONCLUSION: Degree of microhematuria during follow-up is an independent predictor of eGFR decline after adjusting for clinical and histological parameters. Therefore, monitoring the degree of microhematuria as well as proteinuria is important when evaluating patients with IgAN. Additional studies using improvement in microhematuria as a primary surrogate outcome are needed.

Change in right ventricular systolic function after continuous renal replacement therapy initiation and renal recovery.

OBJECTIVE: To describe the associations between right ventricular (RV) function and outcomes of patients with acute kidney injury (AKI) requiring continuous renal replacement therapy (CRRT). METHODS: This is a retrospective study, conducted 2006-2015 at an academic hospital in USA. We included patients with AKI requiring CRRT who had paired echocardiograms within 2 weeks before and after CRRT initiation. We defined improvement in RV systolic function as 2-point improvement on the semiquantitative scale. RESULTS: The cohort included 201 patients. The mean(±SD) age was 59(±16) years with 83(41%) female. The median time of the pre and post echocardiograms relative to CRRT initiation were - 1 day (IQR-3;0) prior to and 3 days (IQR1;7) after CRRT initiation. Thirty-one (15%) patients showed an improvement in their RV function. Using a multivariable logistic regression model, improvement in RV systolic function was associated with lower odds of major adverse kidney events (composite of mortality, need for dialysis or persistently elevated serum creatinine) at 90 days with odds ratio (OR) of 0.37(95%CI:0.17-0.84, p.016). Positive cumulative fluid balance was associated with lower odds of improvement in RV function (OR 0.95 per 1-l increase, p 0.045). CONCLUSION: Serial assessment of RV function among patients with AKI requiring CRRT could provide prognostic value.

New-onset atrial fibrillation in patients with acute kidney injury on continuous renal replacement therapy.

PURPOSE: The mortality of critically ill patients with acute kidney injury (AKI) who require continuous renal replacement therapy (CRRT) remains high. We assessed the incidence and predictors of new-onset atrial fibrillation (NOAF) in this population and its impact on outcomes. MATERIALS AND METHODS: This is a retrospective cohort study of adult intensive care units (ICU) patients who had AKI and received CRRT from December 2006 through November 2015 in a tertiary academic medical center. Cox proportional hazard model was used to evaluate the impact of NOAF on overall mortality. RESULTS: Out of 1398 screened patients, NOAF occurred in 193 (14%) cases. NOAF occurring on CRRT was independently associated with an increased hazard of death at follow-up (HR: 1.26; 95% CI: 1.03-1.56), compared to the group who did not have NOAF. In the multivariable analysis using time-dependent covariates, higher potassium (HR 1.24, 95%CI: 1.01-1.54) and bicarbonate (HR 0.95, 95%CI: 0.92-0.98) levels were associated with increased and decreased risk of NOAF on CRRT, respectively. CONCLUSIONS: NOAF in critically ill patients with AKI receiving CRRT is common and carries an unfavorable prognosis. Prospective studies are required to elucidate modifiable risk factors for NOAF occurring on CRRT.