Hydronephrosis is a medical condition, in which dilation (distention) of the kidneys with urine, resulted from backward pressure on the kidneys when the urine flow is obstructed, occurs.
Usually, the urine flows out of the kidney at extremely low pressure levels, but in obstructed urine flow, the urine backs up in the kidney’s small tubes and the renal pelvis (central collection part), distending the kidneys and putting pressure on kidney’s delicate tissue. The pressure from severe and prolonged Hydronephrosis damages the tissues of the kidney so that function of the kidney is slowly lost.
Hydronephrosis is usually caused by ureteropelvic junction obstructions. Causes of Hydronephrosis consists of following: ureter stones, renal pelvis stones, structural defects, junction kinking, tumor near or in the ureter, ureter narrowing, severe urinary tract infections, pelvic organs cancers, ureterocele, fibrous tissue formation around or in the ureter, ureter compression, and urine backflow from the bladder.
Sometimes, Hydronephrosis happens at the time of pregnancy if the enlarged uterus compresses the ureter. Pregnancy’s hormonal changes can aggravate the problems by decreasing the ureters muscular contractions that normally move urine to the female’s bladder. Such kind of Hydronephrosis commonly ends when the pregnancy ends, although, the ureters and pelvis can remain somewhat dilated for afterward.
Prolonged renal pelvis distention (dilation) may inhibit the rhythmic muscular contraction that usually moves urine down the ureter to the bladder. Nonfunctioning fibrous tissues then can replace the healthy muscular tissues in the ureter walls, causing permanent injury. The symptoms of the Hydronephrosis depends on obstruction cause, its duration and location. In Acute Hydronephrosis, (when obstruction starts suddenly) and obstruction causes renal colic-flank’s intermittent, excruciating pain on the affected side.
In Chronic Hydronephrosis (slowly progressing obstruction), obstruction can produce either flank aching, dull discomfort attacks or no symptoms at all on the damaged part. If the kidney is greatly dilated in a child or infant, a doctor can feel a mass in the flank. Hydronephrosis can be diagnosed by performing several procedures such as intravenous urography, cystoscopy, retrograde urography in adults; and bladder, ureters and kidney ultrasound scanning in children.
The treatment of Hydronephrosis consists of prompt treatment of kidney failure or urinary tract infection, if present. In Acute Hydronephrosis, the urine that collected above the kidney obstruction must be drained promptly with a needle placed through the skin (if infection persist, pain is severe, or kidney function is reduced). If the full obstruction occurs, stones are present, or infection is severe – a catheter to drain the urine, can be placed into the renal pelvis through the flank skin. Chronic Hydronephrosis is treated by relieving urinary obstructions and by treating the causes of the disease. Abnormal or narrow ureter’s section can be removed surgically and the cut ends are joined together.
Sometimes, operation to free ureter from fibrous tissues is required. If the bladder and ureter is be detached surgically, after it is attached to a different bladder area. Urethra’s obstruction may be treated with medications including hormone therapy for prostate cancers, enlargement of the urethra with dilator, or surgery. Other treatment can be necessary for stones that are blocking urine flow. For Chronic Hydronephrosis, the prognosis is less certain.