Viewpoint

The cortex and medulla of the kidney are believed to exist on a tightrope between normal function and hypoxia. The contributions of cortical and medullary hypoperfusion to hypertension have been widely investigated. In this Viewpoint, Thomas Pallone distills current knowledge on the roles of nitric oxide and reactive oxygen species in this setting, and speculates on the implications for future treatment of hypertension.

Elevated blood pressure is a strong and independent risk factor for the development of end-stage renal disease. Various investigators have examined whether all renal diseases are similarly sensitive to high blood pressure and whether they benefit similarly from antihypertensive therapy. Reviewing data from different renal disease populations, authors from the Medical University of Silesia provide their recommendations on the optimal blood pressure goals for slowing progression of renal insufficiency.

Transcriptome-based assessment of blood, urine or biopsy tissue could have a powerful impact on the management of renal transplants, with the potential to detect injurious mechanisms before graft injury is established. This Viewpoint article explores the promise held by transcriptomics and high-density microarrays, and examines the challenges of applying these new technologies in renal transplant recipients.

The plasma concentration of sodium ions normally exceeds the sum of the plasma concentrations of chloride and bicarbonate ions. Calculation of the resulting 'anion gap' can aid the diagnosis of various acid–base and electrolyte disorders. Michael Emmett discusses the utility of this approach, and highlights the potential disrupting factors which should be taken into account when interpreting anion gap calculations.

Recurrence of lupus nephritis after kidney transplantation is often regarded as rare, and transplantation of patients with end-stage renal disease secondary to this condition is common. Several studies, however, have reported a higher incidence of recurrence of lupusnephritis after renal transplantation than the 1–4% which is usually quoted. Weng and Goral discuss reasons for the variation in reported incidence of recurrent lupus nephritis and consider the potential clinical impact of recurrence.

In 1955, the Swiss hematologist Conrad von Gasser coined the term ‘hemolytic uremic syndrome’ to describe the combined symptoms of diarrhea, hemolytic anemia, thrombocytopenia and acute renal failure, which he had observed in five children. Since then, investigators have realized that some forms of hemolytic uremic syndrome can be attributed to genetic abnormalities in circulating and membrane-bound proteins that regulate the complement system. How do these abnormalities influence the course and outcome of the disease, and how should they affect its treatment?