Acute Kidney Injury


Early Stage squareAcute Kidney Injury (AKI) is a sudden episode that impairs the kidney performance, and it can occur over a matter of hours or days. As the kidney is responsible for a variety of functions, including fluid balance and waste secretion, the impact can be the accumulation of fluid and waste plus a decline in urine flow. Other symptoms include swelling in the legs or body, fatigue, shortness of breath, confusion, nausea, chest pain, seizures or coma. Other times there are no symptoms and it is diagnosed by blood tests. An example of an AKI is acute tubular necrosis.

There are many causes of AKI, and some relate to a decline in blood flow to the kidney, which can come from bleeding, heart attack, sepsis, dehydration, organ failure, overuse of some medications (like non-steroidal anti-inflammatory medicines), burns, or allergic reactions. There are also some other conditions (multiple myeloma, cancers, vasculitis and scleroderma) that can also lead to AKI. In addition, some mechanical items that can obstruct the urine flow to the ureter that can also lead to AKI. It is important to recognize and treat AKI, as permanent damage to the kidneys can result.

Current Treatment

The current treatment for AKI is likely to involve hospitalization, as many folks would already be in the hospital for other reasons. It is important to keep track of fluid balance and urine output, and to minimize the nephrotoxic medications that are used. Sometimes the AKI requires use of dialysis to remove waste and help maintain proper fluid balance. At times, even with appropriate treatment, AKI can turn into kidney failure, which can result in the need for a renal transplant or ongoing dialysis.

Focused Ultrasound Treatment

There is recent work using pulsed focused ultrasound to improve the homing of mesenchymal stem cells (MSCs) infused in a mice model after cisplatin-induced AKI. In the acute setting, pulsed focused ultrasound and MSC improved the rate of apoptosis and necrosis by 60% and 80%, respectively, compared to untreated cells. In addition, the combined treatment in established AKI resulted in significant improvement compared to MSC alone or untreated controls. The authors conclude that the combination offers better care than MSC treatment alone, which allows acute and rescue treatment for AKI. This is exciting preclinical work, and hopefully it will lead to human clinical trials.

Notable Papers

Fischer K, Meral FC, Zhang Y, Vangel MG, Jolesz FA, Ichimura T, Bonventre JV. High-resolution renal perfusion mapping using contrast-enhanced ultrasonography in ischemia-reperfusion injury monitors changes in renal microperfusion. Kidney Int. 2016 Jun;89(6):1388-98. doi: 10.1016/j.kint.2016.02.004.

Burks SR, Nguyen BA, Tebebi PA, Kim SJ, Bresler MN, Ziadloo A, Street JM, Yuen PS, Star RA, Frank JA. Pulsed focused ultrasound pretreatment improves mesenchymal stromal cell efficacy in preventing and rescuing established acute kidney injury in mice. Stem Cells. 2015 Apr;33(4):1241-53. doi: 10.1002/stem.1965.