Kidney Failure Attributed to Immunoglobulin A Nephropathy: A USRDS Retrospective Cohort Study of Epidemiology, Treatment Modalities, and Economic Burden.

Rationale & Objective: This study describes the epidemiology, characteristics, and outcomes of patients with immunoglobulin A nephropathy (IgAN)-attributed kidney failure in the US Renal Data System (USRDS) from 2008 to 2018, including health care resource utilization and costs among patients with Medicare-linked data. Study Design: Retrospective cohort study. Setting & Population: Patients with IgAN-attributed kidney failure in the USRDS. Outcomes: Prevalence/incidence, clinical/demographic characteristics, time to kidney transplant, and health care resource utilization and costs. Analytical Approach: Patients with IgAN as primary cause of kidney failure (IgAN cohort) were followed from USRDS registration (index date) until data end/death. Prevalence/incidence were calculated per 1,000,000 US persons. Demographic and clinical characteristics at index and treatment modality during follow-up were summarized. Time from index to kidney transplant was assessed using Kaplan-Meier and competing risk analyses. Health care resource utilization and health care costs were reported among patients with 1 year Medicare Part A+B coverage postindex, including or excluding those who died (Medicare Coverage and 1-year Medicare Coverage subgroups, respectively). Results: The IgAN cohort, Medicare Coverage, and 1-year Medicare Coverage subgroups included 10,101, 1,696, and 1,510 patients, respectively. Mean annual period prevalence and incidence of IgAN-attributed kidney failure were 39.3 and 2.9 per 1,000,000 US persons, respectively. Initial treatment was in-center hemodialysis (63.1%) or kidney transplant (15.1%). Year 1 and 5 kidney transplant rates were 5% and 17%, respectively, accounting for competing risk of death. In the Medicare Coverage and 1-year Medicare Coverage subgroups, 74.4% and 72.3%, respectively, required inpatient admission, 67.3% and 64.4%, respectively, visited the emergency room, and mean total health care costs were $6,293 (SD: $6,934) and $5,284 ($3,455), respectively, per-patient-per-month in the year postindex. Limitations: Drug costs may be underestimated as Medicare Part D coverage was not required; kidney acquisition costs were unavailable. Conclusions: IgAN-attributed kidney failure is associated with substantial clinical and economic burdens. Novel therapies for IgAN that delay kidney failure are needed.

This study of patients in the United States Renal Data System (USRDS) observed fluctuating incidence and increasing prevalence of immunoglobulin A nephropathy (IgAN)-attributed kidney failure from 2008 to 2018. Patients experienced a high clinical burden, with 63% receiving in-center dialysis and over 15% receiving transplantation as initial therapy. In the first year after USRDS registration, nearly three-quarters of patients with Medicare coverage required hospitalization, and around two-thirds visited the emergency room. The total annual health care costs were >$63,000 per patient with IgAN-attributed kidney failure, underscoring the high economic burden of this disorder and currently available treatments. Novel therapies for IgAN are needed to delay or prevent the need for costly dialysis and transplantation after kidney failure.

Clinical Characteristics and Histopathology in Adults With Focal Segmental Glomerulosclerosis.

Rationale & Objective: Few data are available regarding histological features at the time of focal segmental glomerulosclerosis (FSGS) diagnosis among diverse real-world populations. This study describes clinical and histological characteristics and correlates of histological disease severity in adults with FSGS who underwent a clinical kidney biopsy. Study Design: Real-world cohort study with data derived from health records. Setting & Participants: Adults with FSGS by kidney biopsies from Arkana Laboratories from January 1, 2016 to May 31, 2020. Exposure: Race, chronic kidney disease stage, nephrotic proteinuria, age, sex, and hypertension. Outcomes: Severe histological disease, defined as global glomerulosclerosis in >50% of glomeruli and >25% interstitial fibrosis and tubular atrophy (IFTA). Analytical Approach: Demographic, clinical, and histological characteristics were compared between race groups. Correlates of severe disease were analyzed using multiple logistic regression. Results: Among 2,011 patients with FSGS, 40.6% were White, and 23.6% Black. White patients were older (52.8 vs 45.5 years, P < 0.001) with a higher estimated glomerular filtration rate (eGFR) than Black patients (53.5 vs 43.1 mL/min/1.73 m2, P < 0.001). A higher proportion of Black patients had global glomerulosclerosis ≥50% (32.1% vs 14.6%, P < 0.001) or IFTA >50% (34.6% vs 14.7%, P < 0.001). Severe histological disease was more likely in Black patients (OR, 2.46; 95% CI, 1.59-3.79; P < 0.001). A higher proportion of patients with nephrotic than nonnephrotic proteinuria exhibited diffuse foot process effacement. Limitations: Unequal representation across United States regions, missing demographic and clinical data, and lack of data on primary versus secondary FSGS, treatments, or outcomes. Conclusions: Black patients were more frequently diagnosed at younger age with lower eGFR and more severe histological disease compared with White patients. Timelier identification of FSGS could increase the opportunity for therapeutic intervention, especially for high-risk patients, to mitigate disease progression and complications. Plain-Language Summary: Focal segmental glomerulosclerosis (FSGS) accounts for around one-quarter of diagnoses derived from clinical kidney biopsies in the United States. Limited data are available regarding the classes and distribution of histological features at FSGS diagnosis among diverse real-world populations. Analyzing data from US patients who underwent kidney biopsy and were diagnosed with FSGS, we showed that up to half of patients had features of severe histological disease. Of this overall population, Black patients were more frequently diagnosed at a younger age but with more severe histological disease than White patients. The work highlights the need for timelier diagnosis of FSGS to enable intervention at an earlier disease stage.

Corrigendum to "Clinicopathological Characteristics of Adult IgA Nephropathy in the United States" [Kidney International Reports Volume 8, Issue 9, September 2023, Pages 1792-1800].

[This corrects the article DOI: 10.1016/j.ekir.2023.06.016.].

Clinicopathological Characteristics of Adult IgA Nephropathy in the United States.

Introduction: IgA nephropathy (IgAN) is a progressive autoimmune kidney disease and a leading cause of glomerular disease that can result in kidney failure (KF). The median age at diagnosis is 35 to 37 years and approximately 50% of patients will progress to KF within 20 years. We aimed to enhance the understanding of renal histology and chronic kidney disease (CKD) stage at the time of IgAN diagnosis using a large real-world biopsy cohort. Methods: This retrospective cohort study evaluated biopsy data and clinical characteristics from adult patients within the US who were diagnosed with IgAN between January 1, 2016 to May 31, 2020. Descriptive statistics were summarized and relationship(s) between each Oxford Classification (MEST-C) component score with 24-hour proteinuria or CKD stage were examined using regression analysis. Results: A total of 4375 patients (mean age 47.7 years, 62.7% male) met eligibility criteria. Mild to moderate mesangial hypercellularity (47.3%), segmental sclerosis (65.0%), tubular atrophy ≥25% (57.4%), and crescents (18.5%) were identified; and 74.6% of patients were at CKD stage ≥3. Proteinuria ≥1 g/d was associated with higher MEST-C scores, and the odds of mesangial hypercellularity, segmental sclerosis, tubular atrophy, and crescents increased with CKD stage. Conclusion: Most patients with IgAN in our US cohort were diagnosed at CKD stage ≥3 and had high MEST-C scores and proteinuria that are suggestive of significant disease burden at the time of kidney biopsy. Strategies are required to raise awareness and promote earlier detection of asymptomatic urinary abnormalities before extensive irreversible kidney damage has occurred.

Impact of Proteinuria and Kidney Function Decline on Health Care Costs and Resource Utilization in Adults With IgA Nephropathy in the United States: A Retrospective Analysis.

Rationale & Objective: Among patients with IgA nephropathy (IgAN), proteinuria and decline in kidney function may be associated with increased economic burden. This study aimed to provide current information on the epidemiology and economic burden of IgAN in the United States. Study Design: Retrospective cohort study. Setting & Study Population: Overall, 9,984 patients in the Optum's Market Clarity database identified by the presence of at least 2 natural language processing-derived IgAN signs and disease and symptoms terms; 813 with linked claims data included in a health care resource utilization/cost subcohort. Predictor: High-risk proteinuria (≥1 g/d), chronic kidney disease (CKD) stage. Outcomes: Standardized prevalence, health care resource utilization, costs. Analytical Approach: Descriptive statistics for categorical and continuous variables. Direct standardization for prevalence estimation. Generalized linear models for health care resource utilization/costs, reported as per-patient-per-month (PPPM) costs in 2020 US dollars. Results: The estimated standardized US prevalence of IgAN (2016-2020) was 329.0 per 1,000,000 persons. High-risk proteinuria (≥1 vs <1 g/d) was associated with a higher mean PPPM number of outpatient visits (3.49 vs 1.74; P = 0.01) and pharmacy claims (3.79 vs 2.41; P = 0.01), contributing to higher mean total costs PPPM ($3,732 vs $1,457; P = 0.01). Furthermore, higher CKD stage was also associated with higher health care resource utilization (number of outpatient visits PPPM, number of pharmacy claims PPPM, proportion of patients with inpatient visits and emergency department visits; P < 0.001) and mean total cost PPPM (from $2,111 CKD stage 1 to $10,703 CKD stage 5/kidney failure; P < 0.001). Limitations: Generalizability outside of the catchment group for the database, missing data/errors inherent in retrospective database studies, relatively small sample size, use of Optum Market Clarity standardized pricing algorithms, exclusion of out-of-pocket costs. Conclusions: Health care resource utilization and costs were higher for IgAN patients with high-risk proteinuria and worsening kidney function. Treatments that reduce proteinuria and slow CKD disease progression may reduce the economic burden associated with IgAN. Plain-Language Summary: Immunoglobulin A nephropathy (IgAN) is a rare kidney disease. Over time, the kidneys may leak protein into the urine (proteinuria). IgAN can lead to kidney failure. Because IgAN is rare, it is hard to know how many people have it. This study used electronic health records to estimate the number of patients with IgAN in the United States, describe the characteristics of patients, and understand their treatments and the costs. The number of patients with IgAN increased between 2016 and 2020. The researchers think this is because doctors learned more about IgAN. Patients with severe disease used more health care resources and had higher costs. The authors believe treatments that slow kidney damage may reduce the cost of treating IgAN.

Humanistic and Economic Burden of IgA Nephropathy: Systematic Literature Reviews and Narrative Synthesis.

BACKGROUND: Immunoglobulin A nephropathy (IgAN) is a progressive inflammatory kidney disease requiring long-term treatment to reduce the risk of progression to kidney failure. Here, we present two systematic literature reviews (SLRs) to identify and summarize literature reporting the humanistic and economic burden of IgAN. METHODS: Electronic literature databases (Ovid Embase, PubMed, and Cochrane) were searched for relevant literature on 29 November 2021, supplemented with gray literature searches. Studies reporting any health-related quality of life (HRQoL) or health state utility outcomes in IgAN patients were included in the humanistic impact SLR, and studies reporting the costs and healthcare resource utilization associated with or economic models of IgAN disease management were included in the economic burden SLR. Narrative synthesis was used to discuss the heterogeneous studies included in the SLRs. Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) and Cochrane guidelines were followed, and all included studies were assessed for risk of bias using the Center for Evidence-Based Management tool for Critical Appraisal of a Survey or the Drummond Checklist. RESULTS: A total of 876 and 1122 references were identified from electronic and gray literature searches for humanistic and economic burden, respectively. Three studies reporting humanistic impact and five studies reporting economic burden met criteria for inclusion in these SLRs. The included humanistic studies reported patient preferences in the USA and China, HRQoL for patients with IgAN in Poland, and impact of exercise on HRQoL for patients with IgAN in China. The five economic studies reported costs of IgAN treatment in Canada, Italy, and China, along with two economic models from Japan. DISCUSSION: Current literature suggests IgAN is associated with substantial humanistic and economic burdens. However, these SLRs demonstrate the paucity of research conducted to specifically describe the humanistic or economic burden of IgAN and highlight the need for further research.

Correction to: The cost-effectiveness of albumin in the treatment of decompensated cirrhosis in Germany, Italy, and Spain.

Following publication of the original article [1], the authors reported that one of the numbers within Fig. 6 contains a mistake.

The cost-effectiveness of albumin in the treatment of decompensated cirrhosis in Germany, Italy, and Spain.

BACKGROUND: Albumin is frequently prescribed in cirrhotic patients with acute decompensation. However, the true cost effectiveness of albumin use in cirrhotic patients is still under debate. OBJECTIVE: To evaluate the cost-effectiveness of albumin in the treatment of decompensated cirrhosis in Germany, Italy, and Spain. METHODS: A decision-tree economic model was developed to evaluate treatments for decompensated cirrhosis from the hospital perspective over a typical inpatient admission. The treatments for large volume paracentesis (LVP) were albumin vs saline, gelatin, or no fluid. The treatments for spontaneous bacterial peritonitis (SBP) were albumin plus antibiotics vs antibiotics alone. The treatments for hepatorenal syndrome (HRS) were albumin plus a vasoconstrictor vs a vasoconstrictor alone. Effectiveness inputs were literature-based. Cost inputs included pharmacy costs and medical complication costs of decompensated cirrhosis. The primary model assessments were incremental cost-effectiveness ratios (ICERs) per life saved and per quality-adjusted life-year (QALY). RESULTS: Albumin was found to be both less costly and more effective relative to saline, gelatin, and no fluid for the treatment of LVP across all 3 countries. For SBP, albumin plus antibiotics was more clinically effective than antibiotics alone in all 3 countries. The combination of albumin plus antibiotics was less costly than antibiotics alone in Germany and Italy, making albumin a dominant treatment (ie, less costly and more effective). In the management of SBP in Spain, albumin plus antibiotics compared to antibiotics alone resulted in ICERs of €1516 per life saved and €3369 per QALY gained. Albumin plus a vasoconstrictor was both less costly and more effective than vasoconstrictor alone in the treatment of HRS across all 3 countries. CONCLUSION: This analysis demonstrates that albumin is cost-effective in terms of lives saved and QALYs gained in the management of decompensated cirrhosis associated with LVP, SBP, or HRS.

Association between albumin administration and survival in cardiac surgery: a retrospective cohort study.

PURPOSE: Albumin is widely used during and after on-pump cardiac surgery, although it is unclear whether this therapy improves clinical outcomes. METHODS: This observational study utilized the Cerner Health Facts® database (a large HIPAA-compliant clinical-administrative database maintained by Cerner Inc., USA) to identify a cohort of 6,188 adults that underwent on-pump cardiac surgery for valve and/or coronary artery procedures between January 2001 and March 2013. Of these, 1,095 patients who received 5% albumin with crystalloid solutions and 1,095 patients who received crystalloids alone on the day of or the day following cardiac surgery were selected by propensity-score matching. The primary outcome was all-cause in-hospital mortality. Three secondary outcomes analyzed include acute kidney injury severity, major morbidity composite, and all-cause 30-day readmissions. RESULTS: In the propensity-score matched cohort, receipt of perioperative 5% albumin was associated with decreased risk of in-hospital mortality (odds ratio [OR], 0.5; 95% confidence interval [CI], 0.3 to 0.9; P = 0.02) and lower all-cause 30-day readmission rates (OR, 0.7; 98.3% CI, 0.5 to 0.9; P < 0.01). Albumin therapy was not associated with differences in overall major morbidity (OR, 0.9; 98.3% CI, 0.7 to 1.2; P = 0.39; composite) or acute kidney injury severity (OR, 0.9; 98.3% CI, 0.6 to 1.4; P = 0.53) compared with therapy with crystalloid solutions. CONCLUSIONS: In this large retrospective study, use of 5% albumin solution was associated with significantly decreased odds of in-hospital mortality and all-cause 30-day readmission rate compared with administration of crystalloids alone in adult patients undergoing on-pump cardiac surgery. These results warrant further studies to examine fluid receipt, including 5% albumin, in surgical populations via randomized-controlled trials.

Fluid resuscitation practices in cardiac surgery patients in the USA: a survey of health care providers.

BACKGROUND: Fluid resuscitation during cardiac surgery is common with significant variability in clinical practice. Our goal was to investigate current practice patterns of fluid volume expansion in patients undergoing cardiac surgeries in the USA. METHODS: We conducted a cross-sectional online survey of 124 cardiothoracic surgeons, cardiovascular anesthesiologists, and perfusionists. Survey questions were designed to assess clinical decision-making patterns of intravenous (IV) fluid utilization in cardiovascular surgery for five types of patients who need volume expansion: (1) patients undergoing cardiopulmonary bypass (CPB) without bleeding, (2) patients undergoing CPB with bleeding, (3) patients undergoing acute normovolemic hemodilution (ANH), (4) patients requiring extracorporeal membrane oxygenation (ECMO) or use of a ventricular assist device (VAD), and (5) patients undergoing either off-pump coronary artery bypass graft (OPCABG) surgery or transcatheter aortic valve replacement (TAVR). First-choice fluid used in fluid boluses for these five patient types was requested. Descriptive statistics were performed using Kruskal-Wallis test and follow-up tests, including t tests, to evaluate differences among respondent groups. RESULTS: The most commonly preferred indicators of volume status were blood pressure, urine output, cardiac output, central venous pressure, and heart rate. The first choice of fluid for patients needing volume expansion during CPB without bleeding was crystalloids, whereas 5% albumin was the most preferred first choice of fluid for bleeding patients. For volume expansion during ECMO or VAD, the respondents were equally likely to prefer 5% albumin or crystalloids as a first choice of IV fluid, with 5% albumin being the most frequently used adjunct fluid to crystalloids. Surgeons, as a group, more often chose starches as an adjunct fluid to crystalloids for patients needing volume expansion during CPB without bleeding. Surgeons were also more likely to use 25% albumin as an adjunct fluid than were anesthesiologists. While most perfusionists reported using crystalloids to prime the CPB circuit, one third preferred a mixture of 25% albumin and crystalloids. Less interstitial edema and more sustained volume expansion were considered the most important colloid traits in volume expansion. CONCLUSIONS: Fluid utilization practice patterns in the USA varied depending on patient characteristics and clinical specialties of health care professionals.

Fluid resuscitation practice patterns in intensive care units of the USA: a cross-sectional survey of critical care physicians.

BACKGROUND: Fluid resuscitation is a cornerstone of intensive care treatment, yet there is a lack of agreement on how various types of fluids should be used in critically ill patients with different disease states. Therefore, our goal was to investigate the practice patterns of fluid utilization for resuscitation of adult patients in intensive care units (ICUs) within the USA. METHODS: We conducted a cross-sectional online survey of 502 physicians practicing in medical and surgical ICUs. Survey questions were designed to assess clinical decision-making processes for 3 types of patients who need volume expansion: (1) not bleeding and not septic, (2) bleeding but not septic, (3) requiring resuscitation for sepsis. First-choice fluid used in fluid boluses for these 3 patient types was requested from the respondents. Descriptive statistics were performed using a Kruskal-Wallis test to evaluate differences among the physician groups. Follow-up tests, including t tests, were conducted to evaluate differences between ICU types, hospital settings, and bolus volume. RESULTS: Fluid resuscitation varied with respect to preferences for the factors to determine volume status and preferences for fluid types. The 3 most frequently preferred volume indicators were blood pressure, urine output, and central venous pressure. Regardless of the patient type, the most preferred fluid type was crystalloid, followed by 5 % albumin and then 6 % hydroxyethyl starches (HES) 450/0.70 and 6 % HES 600/0.75. Surprisingly, up to 10 % of physicians still chose HES as the first choice of fluid for resuscitation in sepsis. The clinical specialty and the practice setting of the treating physicians also influenced fluid choices. CONCLUSIONS: Practice patterns of fluid resuscitation varied in the USA, depending on patient characteristics, clinical specialties, and practice settings of the treating physicians.

Case report: imaging features in a renal transplant patient with calcineurin inhibitor-induced pain syndrome (CIPS).

Post-transplant distal limb bone marrow edema syndrome or calcineurin inhibitor-induced pain syndrome (CIPS) is generally a self-limiting but debilitating acute pain syndrome that has been reported in 2-14 % of renal transplant recipients. The disease is extensively described in the transplant literature in patients receiving the calcineurin inhibitors cyclosporine and tacrolimus. We present a case of CIPS arising in a patient 73 days after renal allograft, review the imaging findings, and discuss proposed etiologies and differential diagnoses. To the authors' knowledge, CIPS has not been characterized as a distinct entity in the radiology literature.

Mycophenolate mofetil in children with frequently relapsing nephrotic syndrome: a report from the Southwest Pediatric Nephrology Study Group.

Children with frequently relapsing nephrotic syndrome (FRNS) often develop adverse effects from prednisone. Attempts to induce long-term remission in such patients have had varying levels of success. In this multicenter, prospective, open-label study, 14 centers enrolled 33 patients with FRNS, all of whom were in remission at the time of entry. Six of the patients were steroid dependent. The patients received mycophenolate mofetil (MMF) 600 mg/m(2) twice daily (maximum 1 g twice daily) for 6 mo. A tapering dosage of alternate-day prednisone was given to each patient during the first 16 wk of MMF therapy. Patients were monitored for relapses of NS during and after MMF therapy. Treatment failure was defined as a relapse of NS. The patients had the following features at study entry: Age 6.8 +/- 2.7 yr (range 2 to 15 yr); 56% male, 44% female; and 50% white; 25% black, and 25% other. Estimated GFR at entry was 138 +/- 42 ml/min per 1.73 m(2). Twenty-four (75%) of 32 patients stayed in remission throughout the 6 mo of MMF therapy. The relapse rate in these patients improved from one episode every 2 mo before MMF to one every 14.7 mo after MMF. Eight patients stayed in remission during the post-MMF period, for periods of 18 to 30 mo, whereas 16 relapsed after stopping MMF. Eight (25%) of 32 patients relapsed while taking MMF. It is concluded that MMF is effective for maintaining remission in patients who have FRNS and receive treatment for at least 6 mo and is associated with a low incidence of adverse events.