The hydronephrosis develops owing to disturbance of outflow of urine and is characterized by expansion of caliceal system, pathological changes of an intersticial tissue of kidneys and an atrophy of its parenchyma. The hydronephrosis right or a left kidney meets equally often, bilateral - only in 5-9 % of cases of this disease.

Signs, current. The hydronephrosis can connection of such complications as an infection, the lithogenesis in a cavity or a trauma of the amazed kidney, is caused with the first signs of the disease, giving the basis for research of urinary system is long to develop asymptomatically, and only. In most cases the hydronephrosis is shown by pains in lumbar area. Attacks of a renal colic are more characteristic for an initial stage of a hydronephrosis. In the further when the wall of a hollow and calyxes is partially replaced with a connecting tissue, a hollow and calyxes lose ability activly to be reduced, the hydronephrosis is shown by dull aches in lumbar area. Pains at a hydronephrosis, as well as at a nephrolithiasis, can arise both in the afternoon, and at night irrespective of on what to a side the patient sleeps. Last sign is important for differential diagnostics of a hydronephrosis with a nephroptosis at which patients prefer to sleep on the patient to a side. At obstruction of the top urinary ways of a dysuria usually does not happen or it arises only during an attack of pains. Other important sign of a hydronephrosis - a hematuria. The gross hematuria is observed at 10-20 % sick by a hydronephrosis, a microhematuria - much more often. Rise in temperature during intensifying pains in lumbar area testifies to connection of an infection. To palpate the enlarged kidney it is possible only at an appreciable hydronephrosis. At appreciable disturbance of function of a kidney the contrast agent can collect in sufficient concentration only in 12 hours or not be allocated at all with the amazed kidney. Additional methods of diagnostics, essentially specifying data clinico radiological methods, are roentgenography and the scanning of kidneys establishing a degree of disturbance of function of a kidney (kidneys). Owing to similarity of signs the hydronephrosis should be differentiated from a nephrolithiasis (not complicated by development of a hydronephrosis) at which by means of a roentgen the stone of a kidney is found out only, from a nephroptosis at which hurt arise at movement, patients prefer to sleep on the patient to a side, the displaced kidney is palpated in position of the patient costing, and on the roentgenograms executed in a prone position and costing, appreciable mobility of a kidney is taped. At a tumour of a kidney unlike a hydronephrosis a palpated kidney dense and tuberous. At a polycystosis tuberous kidneys are palpated from both parties.

The forecast. The bilateral hydronephrosis at increase of the maintenance of a filtrate nitrogen in a blood and other disturbances of a homeostasis leads to a chronic renal failure.