Research Advances

Investigators found a link between the prevalence of CKD and the county level of particulate matter when they assessed 2010 Medicare information on 1.1 million persons as well as air-quality data for all US counties provided by the Environmental Protection Agency.

Researchers have discovered that in mice, a hormone called neuregulin 4 (Nrg4) is secreted by brown fat cells and communicates with the liver to regulate the conversion of sugar into fat. Mice without Nrg4 became obese and developed hallmarks of type 2 diabetes and fatty liver disease. When scientists genetically elevated NRG4 levels in these mice, however, the animals were protected from these metabolic disorders when fed a high-calorie, high-fat diet. In humans, the amount of NRG correlates negatively with obesity.

In a study of 144 incipient renal transplant recipients, higher urinary calprotectin concentrations predicted impaired kidney function 4 weeks,  6 months, and 12 months after transplantation. Urinary calprotectin was superior to current use of absolute change of plasma creatinine to predict allograft function 12 months after transplantation. Urinary calprotectin predicted an increased risk both in transplants from living and deceased donors in the PLOS One study.

Use of the anticoagulant fondaparinux was linked with improved kidney function both immediately after transplantation and several months later in a pig model of kidney transplantation. The treatment protected marginal kidney grafts, while improving functional recovery and reducing chronic lesions in the British Journal of Surgery study.

One of two HALT-PKD Clinical Trials Network studies demonstrated that rigorous blood pressure control conferred benefits over standard control related to a reduced rate of increase in total kidney volume and greater declines in measures of heart and kidney problems for patients with autosomal dominant polycystic kidney disease (ADPKD). However, the other study showed that dual blockade is not superior to an angiotensin-converting enzyme (ACE) inhibitor alone.

Researchers have discovered a second protein linked with membranous nephropathy (MN). In 2009, the international team reported the discovery of phospholipase A2 receptor 1 (PLA2R1) as the protein targeted by autoantibodies in up to 70% of people with MN. In their new study, the investigators found that 15 of 154 patients with idiopathic MN had circulating autoantibodies to thrombospondin type-1 domain-containing 7A (THSD7A) but not to PLA2R1. Analyses of biopsy samples from patients revealed localization of THSD7A to podocytes.

Among 20 patients with a form of papillary renal cell carcinoma (pRCC) called hereditary leiomyomatosis and renal cell cancer (HLRCC) who were treated with bevacizumab and erlotinib, the response rate was 65%, with 13 patients showing tumor shrinkage >30% and 7 patients with stable disease. Among 21 patients with sporadic pRCC who were treated with the combination, the response rate was 29%, with 6 patients showing tumor shrinkage and 12 patients with stable disease. HLRCC and pRCC patients survived without disease progression for a median of 24.2 and 7.4 months, respectively.

Among 1574 adults with preserved kidney function, 20% perceived themselves to have been discriminated against because of their race. Such individuals were more likely to be African American and have a higher education, but they were more likely to be living in poverty. They also tended to have higher systolic blood pressure but a lower prevalence of diabetes. Perceived racial discrimination was linked with greater kidney function decline over 5 years of follow-up, but when analyzed by race and sex, the link remained only among African American women.

A new model could predict which children with chronic kidney disease (CKD) are at highest risk for progressing to end stage renal disease (ESRD). Using existing patient data, the composite scoring system would facilitate early intervention, giving nephrologists the opportunity to slow the disease course. The model, recently published in the Clinical Journal of the American Society of Nephrology, is the first specifically designed to assess the unique characteristics of children with CKD (1).