Metals found in people's urine could detect acute kidney inj
Acute Kidney Injury (AKI) is a rapid deterioration in kidney function over hours or days. It is common, occurring in 10–20% of patients admitted to hospital and about 50% of patients admitted to intensive care. It can be caused by serious illness, major operations, trauma and by some medicines such as chemotherapy. Scientists at the University of Nottingham, working with clinicians in Nottingham University Hospitals (NUH) NHS Trust, have previously reported a pig model of kidney injury, that replicates many features of human AKI. Using this model, they identified, for the first time, that certain urinary metals could be potentially useful clinical biomarkers for early detection of AKI. Working with patients admitted to the Trent Cardiac Center and NUH NHS Trust intensive care, experts tested their hypothesis in two clinical groups at risk for developing AKI. They found that concentrations of the metals rose in urine from AKI patients within an hour after cardiac surgery, and were elevated on admission in ICU patients.

The biomarkers alone, or in combination (e.g. the product of Zn × Cu), had good sensitivity for early identification of patients at risk of moderate to severe AKI and particularly high negative predictive value, suggesting additional efficacy in identifying patients at low risk of AKI. Urinary Cd, Cu and Zn fulfill most desirable characteristics of biomarkers and offer clinical and economic advantages over other reported AKI biomarkers, most of which are proteins. They are unaffected by comorbidity, proteinuria, sex or age. As yet, the investigators have no reported data from children. The urinary metals are also stable in urine at room temperature, which offers advantages in remote care settings, for example in the developing world. Measurement of the metals is amenable to point-of-care testing using cheap screen-printed electrodes and are likely to be far more cost-effective than protein assays.

Scientists have discovered that certain metals found in people's urine, could be potentially useful clinical biomarkers for the early detection of acute kidney injury (AKI).