There are no symptoms in the early stage, but the harm is great in the later stage! Beware of the "silent killer" - kidney atrophy

During a physical examination, Xiao Li found that his left kidney was 100 mm long and his right kidney was 87 mm long. The doctor at the physical examination center told him that he had mild renal atrophy and that he needed to have a follow-up examination every 3 to 6 months. After returning home, Xiao Li did not find any abnormalities in his body and forgot about it over time. It was not until a routine physical examination one year later that he found that his left kidney had shrunk to 93 mm and his right kidney had shrunk to 75 mm. At this time, the doctor at the physical examination center told him that he must go to the hospital immediately. When Xiao Li went to the hospital for an examination, he found that the glomerular filtration rate of his left kidney was 41.16 ml/(min·1.73㎡), and the glomerular filtration rate of his right kidney was only 6.65 ml/(min·1.73㎡), and his right kidney had basically lost its function.

What is renal atrophy?

The size of kidneys varies from person to person. Generally, healthy adults have two kidneys, which are 10 to 12 cm long, 5 to 6 cm wide, and 3 to 4 cm thick. The reduction in kidney size is clinically called renal atrophy, which can be manifested as one kidney being significantly smaller than the other side or both kidneys being smaller than normal, including left kidney atrophy, right kidney atrophy, and bilateral kidney atrophy.

Renal atrophy can be divided into congenital renal atrophy and secondary renal atrophy.

● Congenital renal atrophy is due to various reasons during the embryonic period that lead to insufficient development of renal tissue, resulting in congenital maldevelopment of the kidneys and smaller size.

● Secondary renal atrophy is often caused by various kidney diseases, such as chronic glomerulonephritis, chronic pyelonephritis, end-stage renal disease, reflux nephropathy, ischemic nephropathy, renal cortical necrosis, hypertension, diabetes, renal tuberculosis, kidney stones, renal artery stenosis or obstruction, renal tumors, and renal cysts. In addition, trauma and surgery can also lead to secondary renal atrophy.

The renal function of patients with renal atrophy has partially or completely disappeared. There are generally no obvious clinical symptoms in the early stages. More obvious symptoms will only appear when the renal function is lost by 30% to 40%. Patients may experience nausea, vomiting, loss of appetite, edema, changes in urine volume, anemia and other symptoms. If the condition continues to deteriorate, uremia will occur.

What tests are needed for renal atrophy?

1. Renal color Doppler ultrasound examination: It can provide a preliminary understanding of kidney size, renal parenchymal thickness and intrarenal blood flow signals. It can also rule out the possibility of renal atrophy caused by kidney stones, tumors, etc.

2. Magnetic resonance imaging: can accurately reflect the degree of renal atrophy.

3. Laboratory examination: Renal function can be judged by multiple indicators such as blood creatinine, glomerular filtration rate, creatinine clearance rate, etc. In addition, patients with renal atrophy may have hematuria, so routine urine examination + microscopic examination should be performed.

4. Others: Hypertension, diabetes, etc. may cause renal atrophy. In addition to the above examinations, blood pressure and blood sugar levels must also be measured.

How should renal atrophy be treated?

Treatment principles

Protect residual renal function, prevent, treat and delay renal failure.

1. Avoid and control factors that aggravate kidney damage, such as avoiding the use of nephrotoxic drugs, controlling high blood pressure, high blood sugar, high blood lipids, etc. In addition, change bad living habits and pay attention to healthy diet, choose a low-salt, high-quality, low-protein diet.

2. Treat renal atrophy according to the cause:

● If the cause of renal atrophy is renal artery stenosis, renal artery dilatation and stent implantation can be performed to relieve the renal artery stenosis. After restoring renal blood supply, renal atrophy may be slowed down.

● If renal atrophy is caused by chronic urinary tract infection, choose appropriate antibiotics for treatment.

● Renal atrophy caused by urinary stones, hydronephrosis, tumors and trauma is generally related to urinary tract obstruction. The corresponding surgical operation can be selected to relieve the obstruction according to the condition. Generally, after the obstruction is completely relieved within 1 week, the kidneys can restore their original function.

● If renal atrophy is caused by chronic kidney disease, renal function is generally difficult to reverse. If it develops to the stage of uremia, dialysis treatment is required and kidney transplantation should be considered if necessary.