Bilateral Renal Cortical Thinning

Definition and Causes

Bilateral renal cortical thinning is a radiological finding characterized by decreased thickness of the renal cortex in both kidneys, typically indicating chronic kidney disease (CKD) and progressive loss of functional renal tissue, with common causes including chronic kidney disease (CKD), hypertension, renovascular disease, diabetes mellitus, glomerulonephritis, chronic pyelonephritis, autosomal dominant polycystic kidney disease (ADPKD), and nephrotoxic medications 1, 2, 3, 4, 5, 6
The American College of Radiology suggests that chronic kidney disease (CKD) is the most common underlying cause of bilateral renal cortical thinning 1
Hypertension, particularly long-standing, poorly controlled hypertension, is a common cause of bilateral renal cortical thinning, according to the American Heart Association 2, 3
Renovascular disease, including atherosclerotic renal artery stenosis and fibromuscular dysplasia, can also cause bilateral renal cortical thinning, as stated by the American College of Cardiology 4, 5
Diabetes mellitus can lead to bilateral renal cortical thinning through diabetic nephropathy, as reported by the American Diabetes Association 2
Autosomal dominant polycystic kidney disease (ADPKD) can cause bilateral renal cortical thinning in advanced stages, according to the National Kidney Foundation 6

Ultrasound is typically the first-line imaging modality for identifying renal cortical thinning, with findings including increased echogenicity, cortical thinning, and reduced kidney size, as recommended by the American Institute of Ultrasound in Medicine 1
CT scan can quantify cortical thickness and identify other structural abnormalities, according to the American College of Radiology 1
MRI provides detailed assessment of renal parenchyma without radiation exposure, as stated by the American College of Radiology 1
Nuclear medicine scans, such as DMSA scans, can assess functional renal cortical tissue and identify areas of scarring, as reported by the Society of Nuclear Medicine and Molecular Imaging 1

Bilateral renal cortical thinning is an indicator of CKD, representing irreversible kidney damage and correlating with reduced renal function, as stated by the National Kidney Foundation 1
The degree of cortical thinning correlates with severity of renal dysfunction, according to the American Society of Nephrology 1
Hypertension management is crucial, as bilateral renal cortical thinning may indicate renovascular hypertension requiring specific treatment approaches, as recommended by the American Heart Association 2, 3
Medication considerations are important, requiring caution with nephrotoxic medications and dosage adjustments for renally cleared drugs, as stated by the American College of Clinical Pharmacy 1
The presence of bilateral renal cortical thinning should guide management, including blood pressure control, medication review, renal function monitoring, cardiovascular risk management, and consideration of renovascular disease, as recommended by the American College of Cardiology 1, 2, 3, 4, 5