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Anechogenic mass in the kidney
Last reviewed: 04.07.2025
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In clinical medicine, there is no disease called anechoic formation in the kidney, because it is one of the diagnostic signs of some nephrological pathologies, which is detected during ultrasound examination (ultrasound) of the kidneys.
An anechoic formation in the kidney is a “deaf” (not reflecting ultrasound waves) zone determined on the echogram of this organ, visualized as a dark spot.
As ultrasound diagnostics specialists note, the image formed by reflected ultrasound does not show dense tissue structures, but fluid accumulations. And in most cases with kidneys, these formations are cystic.
Causes anechogenic mass in the kidney
The main causes of anechoic formations in the kidney are the presence of cysts. It is this type of formation that is characterized by echo-negativity during ultrasound examination of any visceral organs. In addition, cysts, which are isolated rounded cavities-capsules containing fluids, create a clearer image of distant tissue structures of the kidney on the echogram (as doctors say, distal enhancement).
A renal cyst is usually determined by ultrasound as an anechoic avascular formation in the kidney, that is, there are no vessels and no blood circulation.
To date, the pathogenesis of cystic formations remains unclear. Nephrologists and urologists call congenital kidney cysts multilocular and associate their appearance with anomalies of intrauterine development. Also, the involvement of frequently diagnosed inflammations in the renal pelvis (pyelonephritis), the presence of kidney stones (nephrolithiasis) or infection of the kidneys with M. tuberculosis and the development of renal tuberculosis in the development of cystic anechoic formations in the kidneys is not excluded.
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Symptoms anechogenic mass in the kidney
Simple kidney cysts, a type of benign formation, are often detected during an ultrasound performed for another reason, since in two-thirds of cases there are no symptoms for this pathology, and the cyst itself does not require treatment.
But if a simple kidney cyst grows large enough, symptoms of an anechoic formation in the kidney may include: dull pain in the lumbar region, abdomen, or side; fever; the appearance of blood in the excreted urine (hematuria); difficulty urinating (due to pressure from the cyst on the renal pelvis).
Forms
A distinction is made between simple and complex cysts; single (solitary) and multiple; peripheral (subcapsular and cortical); cysts in the cortical or medullary tissues of the kidney (parenchyma cysts); cysts of the renal sinus (sinus renalis), etc.
Complications and consequences
Sometimes cystic kidney disease can cause complications, including: infection (with increased body temperature and increased pain); rupture of the cyst (with severe pain in the back or side); disruption of the normal passage of urine due to compression of the ureter, which can lead to swelling of the kidney (hydronephrosis). And the consequences of multiple cysts, diagnosed as polycystic kidney disease, can be expressed in partial or complete atrophy of the organ, leading to renal failure.
Diagnostics anechogenic mass in the kidney
The following tests are performed: ultrasound with diuretics, ultrasound Doppler of the renal vessels, nephroscintigraphy, computed tomography (including with contrast), blood and urine tests, puncture biopsy.
Differential diagnosis
An anechoic formation in the kidney detected during an ultrasound examination may raise suspicion of a cystic form of a malignant tumor – cystic renal cell carcinoma.
To identify oncopathology, differential diagnostics are carried out, which includes not only the standard ultrasound signs of kidney and ureter pathologies for cystic formations.
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Treatment anechogenic mass in the kidney
Treatment of anechoic formation in the kidney is the treatment of the disease, which was thus revealed during ultrasound examination of the kidneys. Read more - Kidney cyst and Treatment of kidney cyst.