Hydronephrosis and Hydroureter

A condition where obstruction of the urine outflow distal to renal pelvis results in distension of renal pelvis and calyces with urine is called as hydronephrosis. Similarly, when the obstruction is beyond the ureters, there is swelling of the ureters with urine, a condition known as hydroureter in medical parlance. Both these conditions can be unilateral or bilateral, acute or chronic and physiological or pathological.

Causes of Hydronephrosis and Hydroureter

The common causes of hydronephrosis and hydroureter are:

In children, hydronephrosis and hydroureter are generally secondary to some congenital anomalies. These include urethral valves and strictures, and stenosis at the level of either ureterovesical junction or ureteropelvic junction.

In young adults, calculi of the kidneys, ureters or bladder are the most common cause of urinary obstruction, giving rise to hydronephrosis and hydroureter.

In the elderly people, common cause of hydronephrosis and hydroureter are hypertrophy or carcinoma of the prostate gland, calculi of the urinary system or neoplasms in the pelvic or retroperitoneal areas.

This condition is frequently seen in pregnant women (it affects as many as 80% of all pregnant women). It may be either due to the compression of the ureters at the pelvic brim because of the growing fetus, or due to the dilatation of renal calyces under the effect of progesterone. The condition is more common on the right side as compared to left.

Effect of Hydronephrosis and Hydroureter

Prolonged stasis of urine in the kidneys or ureters may lead to infection and sepsis. It may also lead to the formation of calculi and renal scarring.

Chronic obstruction of urine may damage the kidneys and give rise to hypertension.
Prolonged hydronephrosis may give rise to chronic renal failure.

Symptoms of Hydronephrosis and Hydroureter

The symptoms depend upon whether the condition develops suddenly or is chronic in nature.
In case of acute obstruction, the distension caused by urine may lead to severe pain. This can be seen in sudden complete obstruction caused by ureteric calculi or in case of fluid overload which leads to increased urine output as compared to the rate of urine outflow through an area of obstruction.
In case of a slowly developing obstruction or when the obstruction is partial as seen in the cases of pelvic tumors or congenital stricture at the ureteropelvic junction, the pain may be completely absent.
The pain also depends upon the site of obstruction. When the obstruction is at the level of kidneys or upper ureters, the patient complains of pain in his flanks. However, when the obstruction is at the level of lower ureters or the bladder, the patient complains of pain that radiates to the groin region.
The patient may present with anuria in case of sudden complete bilateral obstruction.
Hematuria may be present in case of calculi or malignancy.

Physical findings of Hydronephrosis and Hydroureter

In case of severe hydronephrosis, the doctor may be able to palpate the kidneys.
There may be costovertebral tenderness on the side which is affected.
Lower urinary tract obstruction may give rise to a swollen bladder which can be easily palpated.
Edema of lower extremities can be seen in case of bilateral hydronephrosis.

Treatment of Hydronephrosis and Hydroureter

Medical treatment is usually limited to control of pain and infection. Alkalis may be given to treat uric acid stones and steroids may be given for retroperitoneal fibrosis.
Surgical treatment is the mainstay and depends upon the cause and site of obstruction. Early intervention is desirable to prevent long term damage to the kidneys.

Reference:
http://emedicine.medscape.com/article/436259-clinical