What Is Renal Ischemia?

Ischemic nephropathy refers to a chronic renal vascular disease in which the main trunk of the renal artery or its branch is severely narrowed or obstructed, which causes severe ischemia of the kidney and eventually leads to slow and progressive decline of renal function. At present, chronic ischemic kidney disease is one of the important causes of chronic renal failure in middle-aged and elderly patients (age> 50 years).

Basic Information

Visiting department: Nephrology
Common causes: Renal artery stenosis due to renal atherosclerosis

Common symptoms: Urine routine changes are slight, renal function damage progresses slowly, kidney volume shrinks, asymmetry on both sides, etc.

Causes of ischemic nephropathy

The factors that can cause renal artery stenosis can cause ischemic nephropathy, and the most common clinical is renal artery stenosis caused by renal atherosclerosis. Vasoactive substances, oxidative stress response, pro-inflammatory mediators, and profibrotic factors can all participate in the ischemic injury process of kidney tissue, and eventually lead to irreversible damage to kidney structure.

Clinical manifestations of ischemic nephropathy

Often accompanied by atherosclerotic manifestations of other parts of the body, such as coronary atherosclerotic heart disease (coronary heart disease), stroke, and peripheral vascular arteriosclerosis. The main manifestations of renal lesions are: slow and progressive decline of renal function, such as renal tubular concentrating damage earlier, followed by glomerular impairment, decreased creatinine clearance, and increased serum creatinine; the kidney volume gradually decreases, if two The development of atherosclerotic lesions of the lateral kidney is inconsistent, which can lead to asymmetry in the size of the two kidneys; Changes in routine urine tests are slight; Some patients can hear vascular noise in the abdomen or waist; If the disease coexists with renal vascular hypertension, the typical manifestations of renal vascular hypertension can also be seen.

Ischemic nephropathy

1. Percutaneous renal arteriography Percutaneous renal arteriography is the "gold standard" for diagnosing renal artery stenosis. It can clarify the location, extent, degree, and embolism of renal artery stenosis.
2. Color Doppler ultrasound observation of renal artery trunk and intrarenal blood flow changes, provides indirect information on renal artery stenosis, and can accurately measure the size of both kidneys.
3 Histopathological examination showed glomerular ischemic shrinkage and ischemic sclerosis, renal tubular atrophy and basement membrane ischemic shrinkage, renal interstitial mononuclear cell infiltration and fibrosis.

Ischemic nephropathy diagnosis

The following two conditions are required for diagnosis.
(1) Renal artery stenosis: Percutaneous renal artery angiography is the gold standard for diagnosis. However, renal artery angiography is not suitable for the elderly, those with renal insufficiency, and those who do not prepare or cannot place stents. Color Doppler ultrasound screening of renal arteries can be used.
(2) Clinical manifestations of ischemic nephropathy: slight changes in urinary routine, slow progression of renal function damage, shrinking kidney volume, asymmetrical size on both sides, audible abdomen and vascular noise. Histopathological examination of renal biopsy is generally not required.

Differential diagnosis of ischemic kidney disease

(1) Benign hypertensive nephrosclerosis: There is a history of hypertension, and the clinical manifestations of renal damage usually take 5 to 10 years. Often accompanied by hypertension fundus changes, the two kidneys are the same size and function the same. Renal artery imaging showed no narrowing of the renal artery trunk or its branches.
(2) Atherosclerotic embolic nephropathy: Histopathological examination reveals the gap left by the dissolution of cholesterol crystals in the arterioles, which can be distinguished from ischemic nephropathy.

Ischemic nephropathy treatment

1. Drug therapy is mainly targeted at the basic and concomitant diseases of renal disease (such as renal vascular hypertension), which can reduce the occurrence of complications. Use only if you lose the opportunity for percutaneous transluminal renal angioplasty plus stent implantation and surgical revascularization.
2. For interventional treatment, if the degree of renal artery stenosis reaches 70% to 75%, in order to prevent further deterioration of renal function in patients, percutaneous transluminal renal artery angioplasty and stent implantation should be performed in time.
3 Surgical treatment of patients with contraindications to interventional therapy and those who are expected to have poor curative effect or failed treatment may be treated with surgical vascular reconstruction.