Kidney cyst

A kidney cyst is a neoplasm on the upper layer of the kidney that is considered benign. A cystic formation is a cavity with a capsule and serous fluid. Cysts can have various shapes, they can be simple, consisting of one cavity (chamber), or more complex - multi-chamber. As a rule, a kidney cyst does not grow to large sizes, cystic formations larger than 10 centimeters are extremely rare. The etiology of cyst development has not yet been clarified, although this disease is quite common in clinical urological practice.

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Epidemiology

Kidney cysts are most often diagnosed in men over 45-50 years of age; in women, they are detected much less frequently.

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Causes kidney cysts

The etiology of cyst formation is still unclear, there are several theories put forward by eminent doctors and scientists. However, the diversity of cyst species, sometimes atypical course of the disease, late seeking of medical help and many other reasons do not yet allow to establish a single etiological base. One of the most common causes of cyst formation is pathology of the renal tubule, through which normal urine outflow should occur. If urine accumulates in the tubule, stagnates, it forms a kind of protrusion of the wall and gradually transforms into a cyst. The factor provoking urine stagnation can be any pathology and dysfunction of the kidneys - tuberculosis, stones (urolithiasis), an inflammatory process in the renal pelvis (pyelonephritis), trauma or an oncological process. Cysts most often contain serous matter, often with blood, they can also be filled with renal fluid with pus. Some cystic formations develop simultaneously with an internal tumor formation, which is localized on the walls of the cyst itself.

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Risk factors

Among the most typical causes that provoke neoplasms in the kidneys are the following:

• Tumor of one or both kidneys.
• Stones or sand in the kidneys.
• Pyelonephritis.
• Tuberculosis of the kidneys.
• Venous or ischemic infarction of the kidney.
• Damage to the fibrous capsule of the kidney, kidney hematoma.
• Intoxication, including drug-induced.

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Symptoms kidney cysts

A kidney cyst often does not manifest itself for a long time, that is, the process is asymptomatic. Often, neoplasms are diagnosed during an ultrasound examination designed to detect another pathology. Minor discomfort or pain in the lumbar region, periodically appearing blood in the urine, jumps in blood pressure - these are typical symptoms of kidney pathologies. However, symptoms appear when the cystic formation has already developed and the process goes into an inflammatory or purulent stage. Often a person can feel a painful heaviness in the right or left hypochondrium, this is due to the fact that it pulls the kidney down. Urination is often impaired, since the kidney cyst presses on the parenchyma and blocks the outflow of urine. When the parenchyma is subjected to pressure, a specific hormone is produced - renin, which provokes pressure surges. Almost all cystic formations in the early stages of development do not manifest themselves with clinical signs, doctors call this the "silent course" of the disease. When the size of the cysts increases, or the cysts themselves grow, the symptoms become more obvious and worsen.

A kidney cyst can cause the following complications:

• Formation of kidney stones.
• With severe hypothermia, pyelonephritis, the kidney cyst may become purulent.
• A kidney cyst can burst with any injury to the lumbar region.
• A cystic formation can become malignant and become malignant.
• A kidney cyst can cause kidney failure.

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Forms

Kidney cysts are divided into the following types:

• A single renal cyst is solitary (a peripheral solitary formation).
• A rare type that is diagnosed in 1% of all patients, congenital multicystic disease.
• Cystic transformation of the parenchyma or polycystic disease.
• Dermoid cystic formation filled with connective tissue (embryonic).

A kidney cyst can be localized in the following way:

• Situated under the fibrous layer of the kidney – subcapsular (under the capsule).
• Located directly in the tissues of the kidney – intraparenchymal (in the parenchyma).
• Situated in the gate - in the area of the renal sinus, parapelvic.
• Located in the sinus of the kidney - cortical.

Kidney cysts are divided into categories based on cause and effect. They can be a consequence of intrauterine renal pathologies, i.e. congenital. This is especially true for children whose parents suffered from polycystic disease. In these cases, we can talk about the hereditary etiology of cysts, which can be diagnosed in the liver, ovaries, and other organs. Neoplasms diagnosed as acquired are a consequence of certain pathologies, renal dysfunctions, chronic diseases of the hematopoietic system, cardiovascular diseases.

A kidney cyst can vary in its structure:

• Unicameral neoplasm, single-chamber cystic formation.
• Septate, multilocular or multichambered cysts.

A kidney cyst may contain contents consisting of the following substances:

• Serous, serum fluid, transparent consistency, yellowish tint. Serous substance is a fluid that penetrates through the walls of capillaries into the cavity of a cystic formation.
• Contents in which blood impurities are detected are hemorrhagic contents. This is typical for neoplasms caused by trauma or infarction.
• Contents containing pus, which may be a consequence of an infectious disease.
• The contents may be tumorous, that is, in addition to the fluid inside, a separate internal tumor develops.
• Stones (calcifications) are often found in the contents of cysts.

A cystic formation can be localized in only one kidney and be single, but there are also cystic formations that are dangerous to health and life and affect both kidneys; they can be multiple.

Diagnostics kidney cysts

Neoplasms in the form of cysts are diagnosed using ultrasound examination. Computer tomography and magnetic resonance imaging are also indicated, which provide a clearer and more detailed picture of the localization and structure of cysts. In addition, to exclude or confirm the malignant course of the disease, a radioisotope study of kidney function is used - scintigraphy, Dopplerography, angiography and urography. Blood tests, both general and detailed, urine analysis are mandatory in a complex of diagnostic measures.

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Treatment kidney cysts

If the tumor was diagnosed as a result of a comprehensive examination of another disease, which is most often the case, and if the kidney cyst does not bother the patient and does not manifest itself with painful sensations, at the first stage it requires careful observation. Treatment of the cyst is started only if it changes the function of the kidney and interferes with its normal functioning, for example, a large kidney cyst can press on nearby tissues, disrupt their blood circulation. Cystic formations up to 40-45 mm are not operated on, their condition is monitored using ultrasound scanning, which is recommended to be carried out every six months. Symptomatic therapy is indicated for cysts that are accompanied by pyelonephritis, provoke hypertension or CRF - chronic renal failure. In cases where they grow to large sizes, significantly disrupt the functioning of the kidneys, they are operated on. Surgical intervention can be carried out in ways that depend on the size and growth dynamics of the neoplasms, it can be laparoscopic or in the form of a puncture. Most often, when a kidney cyst is diagnosed in a timely manner, a percutaneous puncture or puncture with subsequent sclerotherapy is used - the introduction of a special drug that "glues" the walls of the cavity of the cystic formation. These interventions are accompanied by ultrasound control, are absolutely safe and low-traumatic. Larger formations are operated using laparoscopy, the technique of which directly depends on where the kidney cyst is located. Laparoscopy is performed using a special endoscope, which is inserted into a small incision at the level of the cyst localization.

Surgical operations are indicated in the following cases:

• In case of severe pain syndrome.
• In case of significant impairment of kidney function.
• For arterial hypertension that cannot be controlled with drug therapy.
• If there are all signs of malignancy of the cystic formation.
• If the tumor size exceeds 40-45 millimeters.
• If parasitic etiology is identified.

A kidney cyst, no matter how it is treated, requires a strict diet:

• Limit salt in the diet, avoid eating salty foods.
• Monitor fluid intake, especially with progressive swelling.
• Limiting the consumption of protein foods.
• Elimination of cocoa products, coffee, sea fish and seafood from the diet.
• Giving up bad habits – alcohol and smoking.

Forecast

• If multiple formations of congenital nature are diagnosed on both kidneys, the prognosis is unfavorable. The neoplasms are incompatible with life.
• Congenital autosomal recessive cystic lesions also have an unfavorable prognosis; children rarely survive beyond two months of age.

A kidney cyst that is diagnosed as simple has an almost 100% positive prognosis, regardless of the method of treatment - outpatient (medication) or surgical intervention.

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