Nephron

Acute kidney injury (AKI) is an increasingly common condition associated with poor health outcomes. Combined with its rising incidence, AKI has emerged as a major public health concern with high human and financial costs. In England, the estimated inpatient costs related to AKI consume 1% of the National Health Service budget. In the United States, AKI is associated with an increase in hospitalization costs that range from $5.4 to $24.0 billion. The most expensive patients are those with AKI of sufficient severity to require dialysis, where cost increases relative to patients without AKI range from $11,016 to $42,077 per hospitalization. Even with these high costs, significant hospital-level variation still exists in the cost of AKI care. In this article, we review the economic consequences of AKI for both the general and critically ill AKI population. Our primary objective is to shed light on an opportunity for hospitals and policymakers to develop new care processes for patients with AKI that have the potential to yield substantial cost savings. By exposing the high rates of death and disability experienced by affected patients and the immense financial burden attributable to AKI, we also hope to motivate scientists and entrepreneurs to pursue a variety of innovative therapeutic strategies to combat AKI in the near term.

Besides cell-bound adhesion molecules, which are of fundamental importance to a large number of physiological and pathological processes, soluble forms of adhesion molecules have been detected in the circulating blood in recent years. Circulating soluble adhesion molecules appear to be biologically active, and raised levels have been reported in a variety of disorders. In the present study, we used ELISA to measure the serum levels of four soluble adhesion molecules in 23 undialyzed patients with chronic renal failure (CRF), 13 patients on continuous ambulatory peritoneal dialysis (CAPD), 17 on chronic hemodialysis (HD) and 18 healthy controls having a similar mean and distribution of ages. The investigated soluble (s) molecules included intercellular adhesion molecule 1 (sICAM-1), vascular cell adhesion molecule 1 (sVCAM-1), sE-selectin and sP-selectin. sICAM-1 was found to be elevated in patients with CRF (p < 0.05), on CAPD (p < 0.02) and HD (p < 0.0001) compared with the controls but levels did not differ between the three patient groups. The higher sVCAM-1 values found in CRF (p < 0.02), CAPD (p < 0.05) and HD (p < 0.0001) as compared to controls again failed to differentiate the three groups of patients. Soluble E-selectin was also raised in the three groups (p < 0.0001) with no difference between them. Increased sP-selectin was found in CRF (p < 0.05), CAPD (p < 0.02) and in HD patients (p < 0.0001) compared to controls, and levels in HD were significantly higher (p < 0.02) than in CRF patients. Predialysis serum molecule levels did not differ between HD patients treated with cuprophan or with polyacrylonitrile dialyzers. HD sessions with both dialyzers had no effect on sICAM-1, while a decrease (p < 0.02) in sP-selectin was found after dialysis with cuprophan. In undialyzed patients with CRF, regression analysis showed a strong linear correlation between serum creatinine and serum levels of each soluble molecule. These results demonstrate that serum levels of soluble adhesion molecules ICAM-1, VCAM-1, E-selectin and P-selectin are elevated in both undialyzed patients with CRF and patients on CAPD or HD. The elevated serum levels of these proteins probably reflect inadequate clearance as well as enhanced synthesis/release.