Urinary Netrin: New Marker for AKI?

Despite all the new and novel ways we discover to diagnose acute kidney injury (AKI) early, nothing has been able to unseat the good 'ol serum creatinine measurement. Aside from the expense of newer markers, there is the laboratory or turn around time issue as well as the question of clinical relevence. Nevertheless, there is a new marker on the block, Netrin-1.

Netrin-1 is a laminin-related axon guidance molecule that is highly induced and excreted in the urine after AKI in animals. A new study in the Clinical Journal of the American Society of Nephrology set to determined the utility of urinary netrin-1 levels to predict AKI in humans undergoing cardiopulmonary bypass (CPB).

The results suggest that netrin-1 is an early, predictive biomarker of AKI after CPB and may allow for the reliable early diagnosis and prognosis of AKI after CPB, before the rise in serum creatinine. Whether this is clinically relevant or will be commercially available is unclear. It is uncertain how this information should materially change the typical post operative ATN patient course or what the health care provider could do differently by obtaining this information. Can they link the early finding of an elevated netrin levels in the urine and a change in the clinical course of a typical post-op ATN? Until then, I will stick to the good old fashioned serum creatinine.