Polycystic kidney disease

Polycystic kidney disease

Polycystic kidney disease is a congenital disease in which cysts appear in both kidneys and gradually enlarge, which leads to atrophy of the functioning parenchyma. Refers to hereditary developmental anomalies and often occurs among members of the same family. The disease progresses throughout life, most often manifests itself and is diagnosed at the age of 20-40 years, but is sometimes found in children and in old age.

Etiology, pathogenesis

The cause of the anomaly is unknown. The pathogenesis is caused by a defect in the embryonic development of the tubules, some of which are transformed into cysts.

Hereditary transmission of polycystic kidney disease is observed in 10% of cases. The kidneys in most patients are enlarged, contain many cysts of various sizes, between which there are areas of preserved parenchyma, in places replaced by connective tissue. The calyces and pelvis are compressed and deformed. Cysts may fester.

Symptoms, course

The disease usually remains asymptomatic for many years. Polycystic disease can be discovered accidentally during examination or surgery. This is explained by the low specificity of symptoms in the early stages of the disease.

When the mass of functioning parenchyma decreases significantly, the concentrating ability of the kidneys is impaired, patients note polyuria and thirst, and then worsening appetite, decreased ability to work, dull pain and a feeling of heaviness in the lumbar region, and headache.

These most common subjective signs of polycystic kidney disease are supplemented by objective data. Polyuria sometimes reaches 3-4 l/day. Urine is colorless, low relative density. Nocturia and isosthenuria are observed.

Proteinuria and daily protein loss are minimal; Cylindruria is also less pronounced. Red blood cells are constantly found in urine sediment, and gross hematuria is also observed. Sometimes gross hematuria is in the nature of profuse, life-threatening renal bleeding.

Leukocyturia often indicates a concomitant infection, sometimes leading to an attack of pyelonephritis and suppuration of cysts. In these cases, the temperature rises (sometimes with chills), pain in the kidney area intensifies, and intoxication increases.

On palpation, an enlarged, lumpy, dense and painful kidney is felt. Polyuria promotes the excretion of metabolic products, and for a long time there may be no azotemia, but over time, the nitrogen excretory function of the kidneys is impaired and azotemia occurs.

During this period, the patient's condition worsens, an unpleasant taste in the mouth and nausea appear. Typically, azotemia in polycystic kidney disease progresses slowly, but renal bleeding, suppuration of cysts, as well as trauma, surgery, pregnancy and childbirth often accelerate the development of azotemia.

The progression of the disease is also facilitated by the often accompanying arterial hypertension, which in most cases is moderate, but sometimes has a malignant course. Arterial hypertension is accompanied by hemodynamic disorders and hypertrophy of the left ventricle of the heart.

In later stages of the disease, anemia and other signs of renal failure are observed.

The diagnosis of polycystic kidney disease is based on history, palpation, renal function tests, ultrasound, radionuclide scanning and x-ray methods.

Treatment is symptomatic only. In cases of severe renal failure, hemodialysis and kidney transplantation are used.

Prognosis: most often the disease leads to renal failure at various times from its onset.