Summary: Extracorporeal “blood purification,” mainly in the form of hemodialysis has been a major portion of the clinical activity of many nephrologists for the past 5 decades. A possibly older procedure, therapeutic plasma exchange, separates and then removes plasma as a method of removing pathogenic material from the patient. In contrast to hemodialysis, therapeutic plasma exchange preferentially removes biologic substances of high molecular weight such as autoantibodies or alloantibodies, antigen-antibody complexes, and Ig paraproteins. These molecular targets may be cleared through two alternative procedures: centrifugal separation and membrane separation. This review presents operational features of each procedure, with relevance to the nephrologist. Kinetics of removal of these plasma constituents are based on the principles of separation by the apheresis technique and by features specific to each molecular target, including their production and compartmentalization in the body. Molecular targets for common renal conditions requiring therapeutic plasma exchange are also discussed in detail.

Summary: Background and objectives: Depression is common and is associated with higher mortality in patients with ESRD or CKD (stage 5). Less information is available on earlier stages of CKD. This study aimed to determine the prevalence of depression and any association with all-cause mortality in patients with varying severity of nondialysis-dependent CKD. Design, setting, participants, & measurements: This is a retrospective study of a national cohort of 598,153 US veterans with nondialysis-dependent CKD stages 1–5 followed for a median of 4.7 years in the US Department of Veterans Affairs Health System. Diagnosis of depression was established as a result of systematic screening and administration of antidepressants. Association of depression with all-cause mortality overall and stratified by CKD stages were examined with the Kaplan–Meier method and in Cox models. Results: There were 179,441 patients (30%) with a diagnosis of depression. Over median follow-up of 4.7 years, depression was associated with significantly higher age-adjusted mortality overall (hazard ratio, 1.55; 95% confidence interval, 1.54–1.57; P<0.001). Sequential adjustments for sociodemographic characteristics and especially for comorbid conditions attenuated this association, which nevertheless remained significant (hazard ratio, 1.25; 95% confidence interval, 1.23–1.26). Conclusions: In this large cohort of predominantly elderly male patients with CKD, prevalence of depression and antidepressant use is high (30%) and is associated with significantly higher all-cause mortality independent of comorbid conditions.

Racial disparities in incidence and outcomes of acute kidney injury (AKI) are pervasive and are driven in part by social inequities and other factors. It is well-documented that Black patients face higher risk of AKI and seemingly have a survival advantage compared to White counterparts. Various explanations have been advanced and suggested to account for this, including differences in susceptibility to kidney injury, severity of illness, and socioeconomic factors. In this review, we try to understand and further explore the link between race and AKI using the incidence, diagnosis, and management of AKI to illustrate how race is directly related to AKI outcomes, with a focus on Black and White individuals with AKI. In particular, we explore the effect of race-adjusted estimated glomerular filtration rate (eGFR) equation on AKI prediction and discuss racial disparities in the management of AKI and how this might contribute to racial differences in AKI-related mortality among Blacks with AKI. We also identify some opportunities for future research and advocacy.

Background: Depression is common and associated with increased morbidity and mortality in elderly (≧65 years) hemodialysis patients. Beck’s Depression Inventory (BDI) and the Geriatric Depression Scale (GDS) have been used in different cohorts to screen for depression. Objectives: We aimed to evaluate the 15-item GDS (GDS-15) as such a tool in elderly hemodialysis patients and compare it with BDI, a previously validated tool in younger hemodialysis patients. Design: Cross-sectional study. Setting: Four out-patient hemodialysis units; 1 based in a university hospital and 3 based in the community. Participants: Hemodialysis patients aged 65 years and older. Intervention: Both tools were administered to all participants, and a geriatric psychiatrist blinded to the results evaluated them for depression by the gold standard psychiatric interview. Measurements: The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for both tools were assessed against the psychiatric interview (n = 62). Results: Patients who were depressed according to the psychiatric interview had significantly higher GDS-15 and BDI scores compared to those not depressed (p < 0.01 both). ROC curves showed high predictive accuracy of the GDS-15 and BDI (area under the curve: 0.808 and 0.729) versus the psychiatric interview. The GDS-15 cutoff with the best diagnostic accuracy was 5 with a sensitivity of 63%, specificity of 82%, PPV of 60% and NPV of 83%. The BDI cutoff with the best diagnostic accuracy was 10 with a sensitivity of 68%, specificity of 77%, PPV of 57% and NPV of 85%. Conclusion: These results provide evidence that the GDS-15 shows validity in comparison to a gold standard and can be used to screen for depression in the elderly hemodialysis population.