Association Between Causative Pathogen and Occurrence of Infection-Related Glomerulonephritis in Infective Endocarditis.

Among patients with pathologically proven infective endocarditis, the association of pathogen with occurrence of infection-related glomerulonephritis (IRGN) was examined in 48 case patients with IRGN and 192 propensity score-matched controls. Bartonella was very strongly associated with IRGN (odds ratio, 38.2 [95% confidence interval, 6.7-718.8]; P < .001); other microorganisms were not.

Proton-pump inhibitor vs. H2-receptor blocker use and overall risk of CKD progression.

BACKGROUND: The relationship between proton-pump inhibitor (PPI) use and chronic kidney disease (CKD) progression remains controversial. Specifically, there is a lack of data evaluating renal outcomes in established CKD patients. The aim of our study is to determine the risk of progression to end-stage kidney disease (ESKD) or death amongst CKD patients on PPI, histamine-2 receptor blocker (H2B), or no anti-acid therapy. METHODS: Using our CKD registry, we evaluated the relationship between PPI and H2B use and outcomes amongst patients with CKD (eGFR < 60), with at least 2 PCP visits in the year prior. A Cox proportional hazards model was used to evaluate the relationship between medication groups and overall mortality, while competing risks regression models were used to determine the risk of ESKD with death as a competing risk. RESULTS: 25,455 patients met inclusion criteria and were stratified according to medication group: no antacid therapy (15,961), PPI use (8646), or H2B use (848). At 4 years, the cumulative incidence of ESKD with death as a competing risk was 2.0% (95% CI: 1.7, 2.4), 1.5% (0.8, 2.8), and 1.6%(1.4, 1.9) among PPI, H2B, and no medication respectively (P = 0.22). The cumulative incidence of death with ESKD as a competing risk was 17.6% (95% CI: 16.6, 18.6), 16.7% (13.7, 19.8), and 17.3% (16.6, 18.0) (P = 0.71). CONCLUSIONS: Use of PPI in a CKD population was not associated with increased mortality or progression to ESKD when compared to H2 blocker and to no acid suppressing therapy.

"What do you think about nephrology?" A national survey of internal medicine residents.

BACKGROUND: Interest in nephrology has been declining among internal medicine residents but the reasons behind this observation are not well characterized. Our objective was to evaluate factors influencing residents' choice of subspecialty. METHODS: This is a mixed-method QUAL-QUAN design study that used the results of our previously published qualitative analysis on residents' perception of nephrology to create and pilot a questionnaire of 60 questions. The final questionnaire was distributed to 26 programs across the United States and a total of 1992 residents. We calculated response rates and tabulated participant characteristics and percentage of participant responses. We categorized choice of fellowship into 2 medical categories (Highly Sought After vs. Less Sought After) and fitted a logistic regression model of choosing a highly vs. less sought after fellowship. RESULTS: Four hundred fifteen out of 1992 (21%) US residents responded to the survey. Of the 268 residents planning to pursue fellowship training, 67 (25%) selected a less sought after fellowship. Female sex was associated with significantly higher odds of selecting a less sought after fellowship (OR = 2.64, 95% CI: 1.47, 4.74). Major factors deterring residents from pursuing nephrology were perception of inadequate financial compensation, broad scope of clinical practice and complexity of patient population. We observed a decline in exposure to nephrology during the clinical years of medical school with only 35.4% of respondents rotating in nephrology versus 76.8% in residency. The quality of nephrology education was rated less positively during clinical medical school years (median of 50 on a 0-100 point scale) compared to the pre-clinical years (median 60) and residency (median 75). CONCLUSION: Our study attempts to explain the declining interest in nephrology. Results suggest potential targets for improvement: diversified trainee exposure, sub-specialization of nephrology, and increased involvement of nephrologists in the education of trainees.

Correction to: Serum magnesium, mortality and disease progression in chronic kidney disease.

Following publication of the original article [1], we have been notified that the name of one author was spelled incorrectly as Georges N. Na khoul, when the correct spelling is Georges N. Nakhoul.

Impact of Uric Acid Levels on Kidney Disease Progression.

BACKGROUND: Hyperuricemia is associated with the progression of chronic kidney disease (CKD), but it is not known whether the relationship is causal. We examined the association of hyperuricemia and uric acid lowering therapy (UALT) with progression of CKD in patients with CKD 3 and 4 in the Cleveland Clinic CKD registry. METHODS: We included 1,676 patients with CKD stages 3 and 4 from Ohio, who had measured their uric acid (UA) levels a year prior to the recording of the second eGFR <60 mL/min/1.73 m2, and follow-up eGFR, between 2005 and 2009. Our primary composite outcome included a 50% drop in eGFR or progression to ESRD. Secondary outcomes included the rate of decline in eGFR, all-cause mortality, progression to ESRD, and a composite measure of progression to ESRD or death. We assessed the association between UA, UALT, and outcomes using Cox models and competing risks regression models. RESULTS: In multivariable models, higher UA was associated with the composite endpoint, but it reached statistical significance only in the 4th quartile (≥8.9 mg/dL). Receipt of UALT was significantly associated with increased risk of the composite outcome. Neither UA nor UALT (considered a time-dependent covariate) was significantly associated with mortality. The inference was similar for UA as high vs. low, quartiles, or continuous. Similarly, neither high UA nor UALT were significantly associated with ESRD, the composite of ESRD and mortality, or eGFR decline. CONCLUSIONS: Hyperuricemia is associated with increased risk of progression to ESRD in patients with CKD stages 3 and 4, but UALT does not ameliorate the risk, suggesting that the relationship is not causal.

Mortality Outcomes of Patients with Chronic Kidney Disease and Chronic Obstructive Pulmonary Disease.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is associated with higher mortality in the general population. We studied the associations between COPD and death among chronic kidney disease (CKD) patients along with reporting cause-specific death data. METHODS: We included 56,960 patients with stages 3 and 4 CKD who were followed in a large health care system. Associations between COPD and all-cause mortality and various causes of death (respiratory deaths, cardiovascular deaths, malignancy-related deaths and deaths due to other reasons) were studied using the Cox proportional hazards and competing risk models. RESULTS: Out of 56,960 CKD patients, 4.7% (n = 2,667) had underlying COPD. Old age, presence of diabetes, hypertension, coronary artery disease, congestive heart failure, and smoking were associated with higher risk for COPD. During a median follow-up of 3.7 years, 15,969 patients died. After covariate adjustment, COPD was associated with a 41% increased risk (95% CI 1.31-1.52) for all-cause mortality, and fourfold increased risk (sub-hazard ratio 4.36, 95% CI 3.54-5.37) for respiratory-related deaths. In a sensitivity analysis that was performed by defining COPD as the use of relevant International Classification of Diseases-9 codes and medications used to treat COPD, similar results were noted. CONCLUSIONS: COPD is associated with higher risk for death among those with CKD, and an underlying lung disease accounts for significant proportion of deaths. These data highlight the need for further prospective studies to understand the underlying mechanisms and potential interventions to improve outcomes in this population.

Fibrillary glomerulonephritis associated with limited scleroderma: a case report.

Fibrillary glomerulonephritis (GN) is a rare glomerular disorder that has been associated with monoclonal gammopathies, malignancies, chronic infections, and autoimmune disorders. We present the case of a 56-year-old woman with limited-type scleroderma and remote discoid lupus, evaluated for dipstick positive hematuria and preserved kidney function. Serologies were negative. Kidney biopsy revealed fibrillary GN. Her renal function and proteinuria remain stable 4 years after her initial diagnosis. This case is unusual both in its presentation and evolution, but mostly because it is the first reported case of fibrillary GN in association with limited type scleroderma.

Serum Potassium, End-Stage Renal Disease and Mortality in Chronic Kidney Disease.

BACKGROUND/AIMS: Hypokalemia and hyperkalemia are often noted in chronic kidney disease (CKD) patients, but their impact on mortality and end-stage renal disease (ESRD) is less well understood. We aimed at studying the associations between potassium disorders, and mortality and progression to ESRD in a CKD population. METHODS: Using our electronic health record-based CKD registry, 36,359 patients with eGFR <60 ml/min/1.73 m(2) and potassium levels measured from January 1, 2005 to September 15, 2009 were identified. We examined factors associated with hypokalemia (<3.5 mmol/l) and hyperkalemia (>5.0 mmol/l) using logistic regression models and associations between serum potassium levels (both as continuous and categorical variables) and all-cause mortality or ESRD using Cox-proportional hazards models. RESULTS: Serum potassium <3.5 mmol/l was noted among 3% and >5.0 mmol/l among 11% of the study population. In the multivariable logistic regression analysis, lower eGFR, diabetes and use of ACE inhibitors or Angiotensin-Receptor Blockers were associated with higher odds of having hyperkalemia. Heart failure and African American race were factors associated with higher odds of hypokalemia. After adjustment for covariates including kidney function, serum potassium <4.0 and >5.0 mmol/l were significantly associated with increased mortality risk, but there was no increased risk for progression to ESRD. Time-dependent repeated measures analysis confirmed these findings. When potassium was examined as a continuous variable, there was a U-shaped association between serum potassium levels and mortality. CONCLUSION: In patients with stage 3-4 CKD, serum potassium levels <4.0 and >5.0 mmol/l are associated with higher mortality but not with ESRD.

Cardiac Surgery Outcomes in Patients Receiving Hemodialysis Versus Peritoneal Dialysis.

Rationale & Objective: We sought to compare outcomes of patients receiving dialysis after cardiothoracic surgery on the basis of dialysis modality (intermittent hemodialysis [HD] vs peritoneal dialysis [PD]). Study Design: This was a retrospective analysis. Setting & Participants: In total, 590 patients with kidney failure receiving intermittent HD or PD undergoing coronary artery bypass graft and/or valvular cardiac surgery at Cleveland Clinic were included. Exposure: The patients received PD versus HD (intermittent or continuous). Outcomes: Our primary outcomes were in-hospital and 30-day mortality. Secondary outcomes were length of stay, days in the intensive care unit, the number of intraoperative blood transfusions, postsurgical pericardial effusion, and sternal wound infection, and a composite of the following 4 in-hospital events: death, cardiac arrest, effusion, and sternal wound infection. Analytical Approach: We used χ2, Fisher exact, Wilcoxon rank sum, and t tests, Kaplan-Meier survival, and plots for analysis. Results: Among the 590 patients undergoing cardiac surgery, 62 (11%) were receiving PD, and 528 (89%) were receiving intermittent HD. Notably, 30-day Kaplan-Meier survival was 95.7% (95% CI: 93.9-97.5) for HD and 98.2% (95% CI: 94.7-100) for PD (P = 0.30). In total, 75 patients receiving HD (14.2%) and 1 patient receiving PD (1.6%) had a composite of 4 in-hospital events (death, cardiac arrest, effusion, and sternal wound infection) (P = 0.005). Out of 62 patients receiving PD, 16 (26%) were converted to HD. Limitations: Retrospective analyses are prone to residual confounding. We lacked details about nutritional data. Intensive care unit length of stay was used as a surrogate for volume status control. Patients have been followed in a single health care system. The HD cohort outnumbered the PD cohort significantly. Conclusions: When compared with PD, HD does not appear to improve outcomes of patients with kidney failure undergoing cardiothoracic surgery. Patients receiving PD had a lower incidence of a composite outcome of 4 in-hospital events (death, cardiac arrest, pericardial effusion, and sternal wound infections).

Patients receiving peritoneal dialysis (PD) are frequently switched to hemodialysis (HD) around the time of an open-heart surgery. More times than not, this is driven by the preference of nonkidney doctors, because HD is perceived to control toxins and fluids better. PD is, however, more advantageous and can achieve similar results while being gentler. In an effort to keep patients on their home PD, we analyzed how they fared when compared with their HD counterparts. Patients maintained on PD did just as well if not better around and after their open-heart surgery. Given the expected increase in patients treated with PD, efforts should be made to maintain them on their home modality even around major surgeries.

Capacity for the management of kidney failure in the International Society of Nephrology North America and the Caribbean region: report from the 2023 ISN Global Kidney Health Atlas (ISN-GKHA).

The International Society of Nephrology Global Kidney Health Atlas charts the availability and capacity of kidney care globally. In the North America and the Caribbean region, the Atlas can identify opportunities for kidney care improvement, particularly in Caribbean countries where structures for systematic data collection are lacking. In this third iteration, respondents from 12 of 18 countries from the region reported a 2-fold higher than global median prevalence of dialysis and transplantation, and a 3-fold higher than global median prevalence of dialysis centers. The peritoneal dialysis prevalence was lower than the global median, and transplantation data were missing from 6 of the 10 Caribbean countries. Government-funded payments predominated for dialysis modalities, with greater heterogeneity in transplantation payor mix. Services for chronic kidney disease, such as monitoring of anemia and blood pressure, and diagnostic capability relying on serum creatinine and urinalyses were universally available. Notable exceptions in Caribbean countries included non-calcium-based phosphate binders and kidney biopsy services. Personnel shortages were reported across the region. Kidney failure was identified as a governmental priority more commonly than was chronic kidney disease or acute kidney injury. In this generally affluent region, patients have better access to kidney replacement therapy and chronic kidney disease-related services than in much of the world. Yet clear heterogeneity exists, especially among the Caribbean countries struggling with dialysis and personnel capacity. Important steps to improve kidney care in the region include increased emphasis on preventive care, a focus on home-based modalities and transplantation, and solutions to train and retain specialized allied health professionals.

Management of adults with acute streptococcal pharyngitis: minimal value for backup strep testing and overuse of antibiotics.

BACKGROUND: Rapid antigen detection tests (RADT) are commonly used to guide appropriate antibiotic treatment of group A beta-hemolytic streptococcal (GABHS) pharyngitis. In adults, there is controversy about the need for routine backup testing of negative RADT. OBJECTIVE: Estimate the costs and benefits in adults of routine backup testing by DNA Gen-probe of negative RADT (Acceava). DESIGN: Observational follow-up study. PARTICIPANTS: All patients aged 18 years and older visiting a Cleveland Clinic generalist physician in 2009 and 2010 with a visit diagnosis of acute pharyngitis (ICD codes 462, 034.0). MAIN MEASURES: The patients were identified using the Cleveland Clinic Epic Clarity database. We determined the proportion of false negative RADT, antibiotic prescription patterns and rate of serious suppurative complications within 30 days of the office visit. KEY RESULTS: Of 25,130 patients with acute pharyngitis, 19% had no testing and 81% were tested. Of the 15,555 patients that had a negative RADT and follow-up DNA probe, 6% had a positive DNA probe. Of the 953 patients who had a negative RADT and a positive DNA strep probe, 48% received an antibiotic prescription at the time of the visit and 51% received an antibiotic prescription after an average of 2.3 days. Only one patient with a negative RADT and no follow-up DNA probe developed a peritonsillar abscess. Overall, of the 15,555 DNA probes performed, management was altered in only 3% of the patients at a total cost of $1,757,715. Fifty-six percent received an antibiotic while only 19.5% had a confirmed strep throat diagnosis. CONCLUSIONS: The false negative rate of Acceava RADT for the diagnosis of GABHS pharyngitis was 6%. We question the benefit of routine DNA probe backup testing in adults because of its substantial cost, an average delay in antibiotic prescribing of over 2 days, and because suppurative complications are very uncommon. We found a high rate of inappropriate antibiotic prescribing.

Comparison of CT acquired cardiac valvular calcification scores in hemodialysis and peritoneal dialysis patients undergoing open heart surgery.

Study objective: Data is scarce regarding which dialysis modality portends more severe cardiac valvular calcification (CVC). Our aim was to compare the degree of CVC in hemodialysis (HD) and peritoneal dialysis (PD) patient cohorts prior to open heart surgery (OHS) using a CT calcium score. Design setting and participants: Dialysis patients who underwent OHS at our institution from 2009 to 2019 and who had pre-surgical cardiac CT were included in our study. We obtained duration of dialysis modality prior to their surgical date. There were two study cohorts to evaluate outcomes of interest: mitral and aortic calcification. CVC was assessed using the Agatston score. Logistic regression was performed to test for the association of PD and HD cumulative dialysis duration with presence of CVC. Results: A total of 214 and 166 patients met inclusion for the mitral and aortic strata, respectively. Age, female sex, and BMI were associated with higher odds of presence of mitral calcification. Age and BMI were associated with higher odds of presence of aortic calcification, while female sex was associated with lower odds in the aortic strata. Cumulative years on PD and cumulative years on HD were not significantly associated with presence of CVC in either cohort. Conclusion: Presence of mitral and aortic calcification for patients undergoing OHS was not significantly associated with cumulative length of PD or HD after adjusting for age, gender, and BMI suggesting that there may be more factors at play in the progression of CVC in end stage renal disease patients than what was previously established.

Renal Genetics Clinic: 3-Year Experience in the Cleveland Clinic.

Rationale & Objective: There has been an increasing demand for the expertise provided by a renal genetics clinic. Such programs are limited in the United States and typically operate in a genomics research setting. Here we report a 3-year, real-world, single-center renal genetics clinic experience. Study Design: Retrospective cohort. Setting & Participants: Outpatient cases referred to the renal genetics clinic of the Cleveland Clinic between January 2019 and March 2022 were reviewed. Analytical Approach: Clinical and laboratory characteristics were analyzed. All genetic testing was performed in clinical labs. Results: 309 new patients referred from 15 specialties were evaluated, including 118 males and 191 females aged 35.1 ± 20.3 years. Glomerular diseases were the leading presentation followed by cystic kidney diseases, electrolyte disorders, congenital anomalies of kidneys and urinary tract, nephrolithiasis, and tubulointerstitial kidney diseases. Dysmorphic features were noted in 27 (8.7%) patients. Genetic testing was recommended in 292 (94.5%) patients including chromosomal microarray (8.9%), single-gene tests (19.5%), multigene panels (77.3%), and exome sequencing (17.5%). 80.5% of patients received insurance coverage for genetic testing. 45% (115/256) of patients had positive results, 25% (64/256) had variants of unknown significance, and 22.3% (57/256) had negative results. 43 distinct monogenic disorders were diagnosed. Family history of kidney disease was present in 52.8% of patients and associated with positive genetic findings (OR, 2.28; 95% CI, 1.40-3.74). 69% of patients with positive results received a new diagnosis and/or a change in the diagnosis. Among these, 39.7% (31/78) of patients received a significant change in disease management. Limitations: Retrospective and single-center study. Conclusions: The renal genetics clinic plays important roles in the diagnosis and management of patients with genetic kidney diseases. Multigene panels are the most frequently used testing modality with a high diagnostic yield. Family history of kidney disease is a strong indication for renal genetics clinic referral.

Therapeutic Advances in Diabetic Nephropathy.

Diabetic kidney disease (DKD) is the most common cause of end-stage kidney disease (ESKD) in the United States. Risk factor modification, such as tight control of blood glucose, management of hypertension and hyperlipidemia, and the use of renin-angiotensin-aldosterone system (RAAS) blockade have been proven to help delay the progression of DKD. In recent years, new therapeutics including sodium-glucose transport protein 2 (SGLT2) inhibitors, endothelin antagonists, glucagon like peptide-1 (GLP-1) agonists, and mineralocorticoid receptor antagonists (MRA), have provided additional treatment options for patients with DKD. This review discusses the various treatment options available to treat patients with diabetic kidney disease.

Anemia of chronic kidney disease: Will new agents deliver on their promise?

Anemia is a well-known complication of chronic kidney disease, and its treatment remains a challenge. Although erythropoiesis-stimulating agents (ESAs) raise hemoglobin levels, their benefits appear to be limited to decreasing the number of blood transfusions needed and perhaps improving quality of life. The newly developed prolyl hydroxylase inhibitors (PHIs)-agents that increase endogenous erythropoietin production-promise to improve outcomes for patients with anemia of chronic kidney disease. Randomized controlled trials have found these drugs to be at least as effective as ESAs, and the drugs are used in other countries. However, PHIs have yet to be approved in the United States.

Dysnatremias, Mortality, and Kidney Failure in CKD: Findings From the Chronic Renal Insufficiency Cohort (CRIC) Study.

Rationale & Objective: Dysnatremias have been associated with an increased risk of mortality in the chronic kidney disease (CKD) population. Our objective is to identify the prevalence of and risk factors associated with dysnatremias in a CKD population and assess the association of dysnatremias with kidney failure and mortality among patients with CKD enrolled in the Chronic Renal Insufficiency Cohort Study. Study Design: Analysis of prospective cohort study. Setting & Participants: Adult patients aged 21-74 years with CKD from the Chronic Renal Insufficiency Cohort study. Predictors: Baseline and time-dependent hyponatremia and hypernatremia. Outcomes: All-cause mortality and kidney failure. Analytical Approach: Baseline characteristics were compared using χ2 tests for categorical variables, analysis of variance for age, and Kruskal-Wallis tests for laboratory variables. Cox proportional hazards models and competing risk models were used to evaluate the association between baseline sodium level and overall mortality. Results: Of a total of 5,444 patients with CKD, 486 (9%) had hyponatremia and 53 (1%) had hypernatremia. Altogether, 1,508 patients died and 1,206 reached kidney failure. In adjusted Cox models, time-dependent dysnatremias were strongly associated with mortality for both hyponatremia (HR, 1.38; 95% CI, 1.16-1.64) and hypernatremia (HR, 1.54; 95% CI, 1.04-2.29). Factors associated with hyponatremia included female sex, diabetes, and hypertension. Regardless of age, time-dependent hypernatremia was associated with an increased risk of kidney failure (HR, 1.64; 95% CI, 1.06-2.53). Baseline and time-dependent hyponatremia were associated with an increased risk of kidney failure in patients younger than 65 (baseline hyponatremia HR, 1.30; 95% CI, 1.03-1.64 and time-dependent hyponatremia HR, 1.36; 95% CI, 1.09-1.70) but not among patients aged >65 years. Limitations: Inability to establish causality and lack of generalizability to hospitalized patients. Conclusions: Dysnatremias are prevalent among ambulatory CKD patients and are associated with mortality and kidney failure. Time-dependent dysnatremias were significantly associated with mortality in patients with CKD. Time-dependent hypernatremia was associated with progression to kidney failure. Baseline and time-dependent hyponatremia were associated with an increased risk of progression to kidney failure in those younger than 65 years.

Aspirin for Primary and Secondary Prevention of Mortality, Cardiovascular Disease, and Kidney Failure in the Chronic Renal Insufficiency Cohort (CRIC) Study.

Rationale and Objective: Chronic kidney disease is a risk enhancing factor for cardiovascular disease (CVD) and mortality, and the role of aspirin use is unclear in this population. We investigated the risk and benefits of aspirin use in primary and secondary prevention of CVD in the Chronic Renal Insufficiency Cohort Study. Study Design: Prospective observational cohort. Setting & Participants: 3,664 Chronic Renal Insufficiency Cohort participants. Exposure: Aspirin use in patients with and without preexisting CVD. Outcomes: Mortality, composite and individual CVD events (myocardial infarction, stroke, and peripheral arterial disease), kidney failure (dialysis and transplant), and major bleeding. Analytical Approach: Intention-to-treat analysis and multivariable Cox proportional hazards model to examine associations of time varying aspirin use. Results: The primary prevention group was composed of 2,578 (70.3%) individuals. Mean age was 57 ± 11 years, 46% women, 42% Black, and 47% had diabetes. The mean estimated glomerular filtration rate was 45 mL/min/1.73 m2. Median follow-up was 11.5 (IQR, 7.4-13) years. Aspirin was not associated with all-cause mortality in those without preexisting cardiovascular disease (CVD) (HR, 0.84; 95% CI, 0.7-1.01; P = 0.06) or those with CVD (HR, 0.88; 95% CI, 0.77-1.02, P = 0.08). Aspirin was not associated with a reduction of the CVD composite in primary prevention (HR, 0.97; 95% CI, 0.77-1.23; P = 0.79) and in secondary prevention because the original study design was not meant to study the effects of aspirin. Limitations: This is not a randomized controlled trial, and therefore, causality cannot be determined. Conclusions: Aspirin use in chronic kidney disease patients was not associated with reduction in primary or secondary CVD events, progression to kidney failure, or major bleeding.