Utilization of Cystatin C in the Outpatient Setting.

Introduction: Serum creatinine is the traditional biomarker for estimating glomerular filtration rate (eGFR). Cystatin C is an alternative biomarker for which estimating equations exist. The use of cystatin C testing, and the interrelationships among the recently revised Chronic Kidney Disease Epidemiology (CKD-EPI) 2021 estimating equations, was evaluated in a national outpatient laboratory dataset.

Chronic Kidney Disease Testing Among At-Risk Adults in the U.S. Remains Low: Real-World Evidence From a National Laboratory Database.

Objective: An estimated 37 million Americans have chronic kidney disease (CKD). Nearly 90% do not know about their condition because of low awareness about the importance of CKD testing and diagnosis among practitioners and people at risk for CKD. This study uses data from a national clinical laboratory to identify guideline-recommended CKD testing rates across the U.

The Epidemiologic Burden of Tacrolimus Variability among Kidney Transplant Recipients in the United States.

Background: Within-patient tacrolimus level variability >30% has been shown to be a risk factor for de novo donor-specific antibody formation and death-censored graft failure among kidney transplant recipients. The burden of tacrolimus variability and the correlation between variability and subtherapeutic tacrolimus levels were examined in a large national data set.

Methods: All tacrolimus levels drawn at LabCorp® facilities in the United States with a diagnosis code for kidney transplant between November 2011 and September 2017 were examined, excluding values that could represent new allografts.

A laboratory-based algorithm to predict future kidney function decline in older adults with reduced estimated glomerular filtration rate .

Background: Reduced estimated glomerular filtration rate (eGFR) in older adults is common and may reflect normal aging or significant kidney disease. Our objective was to develop a predictive model to better triage these individuals using routine laboratory data.

Materials And Methods: Using a large US laboratory data set, we calculated individual eGFR regression slopes for 43,523 individuals aged 60 - 75 years with baseline eGFRs between 30 and 59 mL/min/1.

The role of the 24-h urine collection in the management of nephrolithiasis.

Recurrent nephrolithiasis is a common chronic condition that is often preventable with dietary modification and pharmacologic therapy. Patients with recurrent kidney stones should have a metabolic evaluation, consisting of radiologic studies to assess stone burden, crystallographic stone analysis, and laboratory studies including standard serum chemistries and 24 h urine collection(s). This article focuses on the interpretation of urine chemistries to identify lithogenic risk factors and assess the contribution of diet to the formation of kidney stones.

Clinical decision support improves physician guideline adherence for laboratory monitoring of chronic kidney disease: a matched cohort study.

Background: Guidelines exist for chronic kidney disease (CKD) but are not well implemented in clinical practice. We evaluated the impact of a guideline-based clinical decision support system (CDSS) on laboratory monitoring and achievement of laboratory targets in stage 3-4 CKD patients.

Methods: We performed a matched cohort study of 12,353 stage 3-4 CKD patients whose physicians opted to receive an automated guideline-based CDSS with CKD-related lab results, and 42,996 matched controls whose physicians did not receive the CDSS.

Current recommended 25-hydroxyvitamin D targets for chronic kidney disease management may be too low.

Objective: It is uncertain whether increasing 25-hydroxyvitamin D (25-D) levels in chronic kidney disease (CKD) patients above those recommended by current guidelines result in progressive amelioration of secondary hyperparathyroidism. Our objective was to identify a potential therapeutic 25-D target which optimally lowers plasma parathyroid hormone (PTH) without producing excessive hypercalcemia or hyperphosphatemia in CKD.

Methods: We performed a cross-sectional analysis of 14,289 unselected stage 1-5 CKD patients from US primary care and nephrology practices utilizing a laboratory-based CKD clinical decision support service between September 2008 and May 2012.

Contribution of calcium, phosphorus and 25-hydroxyvitamin D to the excessive severity of secondary hyperparathyroidism in African-Americans with CKD.

Background: Parathyroid hormone (PTH) levels in African-American (AA) chronic kidney disease (CKD) patients exceed those in patients of other races; mechanisms are unknown.

Methods: We performed a cross-sectional analysis of initial laboratory data collected on 2028 CKD patients (505 AA) from US practices using a laboratory CKD service. Serum calcium (Ca), phosphorus (P), 25-hydroxyvitamin D (25-D) and plasma PTH levels were compared between the two groups.

Trends in kidney donation among kidney stone formers: a survey of US transplant centers.

Background: Living kidney donation is on the rise and acceptance criteria for potential donors are evolving to include more 'complex' patients such as kidney stone formers. Transplant centers are faced with sparse data on patient outcomes when evaluating potential donors who are stone formers; thus, attitudes and practice can differ greatly between centers.

Methods: We conducted a survey of United States kidney transplant programs to assess current trends in the approach to dealing with stone formers who are evaluated for kidney donation.

Acute hepatitis B infection in a long-term hemodialysis patient despite persistent natural immunity.

Hepatitis B infections are a distinct clinical problem in hemodialysis patients. Naturally acquired antibodies from a prior hepatitis B virus infection generally are considered to be immunoprotective for subsequent infections. We describe a new-onset hepatitis B virus infection in a hemodialysis patient despite persistent protective levels of naturally acquired antibodies to hepatitis B surface antigen.