New diagnostic approach for identifying diabetic kidney disease emerges, utilization of 23Na MRI technique.

The gold standard test for predicting the onset of diabetic kidney disease is albuminuria. However, detecting albuminuria alone has limited sensitivity and specificity in end-stage renal failure with a decreased estimated glomerular filtration rate. This is supported by several reports, which state that about half of the type 2 diabetes patients who developed kidney dysfunction showed no preceding albuminuria.

In this study, the authors propose the possibility of diagnosing tubular abnormalities in diabetic kidney disease at an early stage and connecting them to treatment by combining the evaluation of sodium concentration using 23Na MRI with the measurement of urinary albumin, commonly used in diabetic testing.

23Na MRI, which images 23Na instead of the clinically applied 1H in existing MRI, visualizes metabolic changes in sodium. Although there have been previous reports of 23Na MRI studies, capturing sodium concentrations equivalent to physiological saline and visualizing them clearly in MRI has been challenging because the amount of sodium in vivo is much smaller than hydrogen, resulting in extremely small signal values. This study optimized the newly developed 23Na MRI to image the kidneys of mice, enabling detailed and clear imaging

This study used 6-week-old diabetic model mice (db/db mice) at an early stage when no tissue damage was observed in the kidneys and imaged the kidneys using a 9.4 Tesla vertical magnet MRI device optimized by the research group. Compared to control mice, the formation of the countercurrent multiplication system in the kidney was weakened, as revealed by the 23Na-visualization images.

Reference:“Sodium magnetic resonance imaging shows impairment of the countercurrent multiplication system in diabetic mice kidney” was published on March 23, 2023, in the scientific journal “Kidney360” of the American Society of Nephrology, and the DOI is 10.34067/KID.0000000000000072.