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The best way to prevent bladder stones is to drink plenty of liquids. Juices containing citrates are thought to reduce the risk of stone formation. A study published in the "Clinical Journal of the American Society of Nephrology" indicate orange juice is more effective at preventing stone formation than other citrus juices. Men who have difficulty with urination due to prostatic hypertrophy should seek treatment. In those with benign prostatic hyperplasia urinating in a sitting position appears to improve bladder emptying which might decrease bladder stones in this group.
Endoscopic injection involves applying a gel around the ureteral opening to create a valve function and stop urine from flowing back up the ureter. The gel consists of two types of sugar-based molecules called dextranomer and hyaluronic acid. Trade names for this combination include Deflux and Zuidex. Both constituents are well-known from previous uses in medicine. They are also biocompatible, which means that they do not cause significant reactions within the body. In fact, hyaluronic acid is produced and found naturally within the body.
Duplicated ureter is the most common renal abnormality, occurring in approximately 1% of the population.
Race: Duplicated ureter is more common in Caucasians than in African-Americans.
Sex: Duplicated ureter is more common in females. However, this may be due to the higher frequency of urinary tract infections in females, leading to a higher rate of diagnosis of duplicated ureter.
Duplicated ureter or Duplex Collecting System is a congenital condition in which the ureteric bud, the embryological origin of the ureter, splits (or arises twice), resulting in two ureters draining a single kidney. It is the most common renal abnormality, occurring in approximately 1% of the population. The additional ureter may result in a ureterocele, or an ectopic ureter.
Treatment of hydronephrosis focuses upon the removal of the obstruction and drainage of the urine that has accumulated behind the obstruction. Therefore, the specific treatment depends upon where the obstruction lies, and whether it is acute or chronic.
Acute obstruction of the upper urinary tract is usually treated by the insertion of a nephrostomy tube. Chronic upper urinary tract obstruction is treated by the insertion of a ureteric stent or a pyeloplasty.
Lower urinary tract obstruction (such as that caused by bladder outflow obstruction secondary to prostatic hypertrophy) is usually treated by insertion of a urinary catheter or a suprapubic catheter.Surgery is not required in all prenatally detected cases.
The goal of treatment is to minimize infections, as it is infections that cause renal scarring and not the vesicoureteral reflux. Minimizing infections is primarily done by prophylactic antibiotics in newborns and infants who are not potty trained. However, in children who are older, physicians and parents should focus on bowel and bladder management. Children who hold their bladder or who are constipated have a greater number of infections than children who void on a regular schedule. When medical management fails to prevent recurrent urinary tract infections, or if the kidneys show progressive renal scarring then surgical interventions may be necessary. Medical management is recommended in children with Grade I-III VUR as most cases will resolve spontaneously. A trial of medical treatment is indicated in patients with Grade IV VUR especially in younger patients or those with unilateral disease. Of the patients with Grade V VUR only infants are trialled on a medical approach before surgery is indicated, in older patients surgery is the only option.
Increasing fluid intake can facilitate the passage of small bladder stones. However, larger stones may require other methods of treatment. Fragmentation of bladder stones can be achieved by use of a cystoscope which is inserted into the bladder. The urologist visualizes the stone and uses ultrasonic energy or laser lithotripsy to cause fragmentation of the stones into small pieces, which are then flushed out of the bladder. This procedure requires anesthesia and may require admission to a hospital. Complications of this treatment include infection and damage to the bladder. Some stones are too large even for cystoscopic treatment and may require open cystotomy, in which an incision is made in the bladder and the stones are removed manually.
Treatment, depending on cause, may require prompt drainage of the bladder via catheterization, medical instrumentation, surgery (e.g., endoscopy, lithotripsy), hormonal therapy, or a combination of these modalities.
Treatment of the obstruction at the level of the ureter:
Most small stones are passed spontaneously and only pain management is required. Above 5 mm the rate of spontaneous stone passage decreases. NSAIDs (non-steroidal anti-inflammatory drugs), such as diclofenac or ibuprofen, and antispasmodics like butylscopolamine are used. Although morphine may be administered to assist with emergency pain management, it is often not recommended as morphine is very addictive and raises ureteral pressure, worsening the condition. Oral narcotic medications are also often used. There is typically no position for the patient (lying down on the non-aching side and applying a hot bottle or towel to the area affected may help). Larger stones may require surgical intervention for their removal, such as shockwave lithotripsy, ureteroscopy or percutaneous nephrolithotomy. Patients can also be treated with alpha blockers in cases where the stone is located in the ureter.
Stone size influences the rate of spontaneous stone passage. For example, up to 98% of small stones (less than in diameter) may pass spontaneously through urination within four weeks of the onset of symptoms, but for larger stones ( in diameter), the rate of spontaneous passage decreases to less than 53%. Initial stone location also influences the likelihood of spontaneous stone passage. Rates increase from 48% for stones located in the proximal ureter to 79% for stones located at the vesicoureteric junction, regardless of stone size. Assuming no high-grade obstruction or associated infection is found in the urinary tract, and symptoms are relatively mild, various nonsurgical measures can be used to encourage the passage of a stone. Repeat stone formers benefit from more intense management, including proper fluid intake and use of certain medications. In addition, careful surveillance is clearly required to maximize the clinical course for people who are stone formers.
Ectopic ureter (or ureteral ectopia) is a medical condition where the ureter, rather than terminating at the urinary bladder, terminates at a different site. In males this site is usually the urethra, in females this is usually the urethra or vagina. It can be associated with renal dysplasia, frequent urinary tract infections, and urinary incontinence (usually continuous drip incontinence). Ectopic ureters are found in 1 of every 2000–4000 patients, and can be difficult to diagnose, but are most often seen on CT scans.
Ectopic ureter is commonly a result of a duplicated renal collecting system, a duplex kidney with 2 ureters. In this case, usually one ureter drains correctly to the bladder, with the duplicated ureter presenting as ectopic.
Definitive causes of ureterocele have not been found. While the abnormal growth occurs within the uterus, it has not been substantiated that genetics are to blame.
Specific therapy should be tailored to the type of stones involved. Diet can have a profound influence on the development of kidney stones. Preventive strategies include some combination of dietary modifications and medications with the goal of reducing the excretory load of calculogenic compounds on the kidneys. Current dietary recommendations to minimize the formation of kidney stones include:
- Increasing total fluid intake to more than two liters per day of urine output.
- Increasing citric acid intake; lemon/lime juice is the richest natural source.
- Moderate calcium intake
- Limiting sodium intake
- Avoidance of large doses of supplemental vitamin C
- Limiting animal protein intake to no more than two meals daily (an association between animal protein consumption and recurrence of kidney stones has been shown in men).
- Limiting consumption of cola soft drinks, which contain phosphoric acid, to less than one liter of soft drink per week.
Maintenance of dilute urine by means of vigorous fluid therapy is beneficial in all forms of nephrolithiasis, so increasing urine volume is a key principle for the prevention of kidney stones. Fluid intake should be sufficient to maintain a urine output of at least per day. A high fluid intake has been associated with a 40% reduction in recurrence risk. The quality of the evidence for this, however, is not very good.
Calcium binds with available oxalate in the gastrointestinal tract, thereby preventing its absorption into the bloodstream, and reducing oxalate absorption decreases kidney stone risk in susceptible people. Because of this, some nephrologists and urologists recommend chewing calcium tablets during meals containing oxalate foods. Calcium citrate supplements can be taken with meals if dietary calcium cannot be increased by other means. The preferred calcium supplement for people at risk of stone formation is calcium citrate because it helps to increase urinary citrate excretion.
Aside from vigorous oral hydration and consumption of more dietary calcium, other prevention strategies include avoidance of large doses of supplemental and restriction of oxalate-rich foods such as leaf vegetables, rhubarb, soy products and chocolate. However, no randomized, controlled trial of oxalate restriction has yet been performed to test the hypothesis that oxalate restriction reduces the incidence of stone formation. Some evidence indicates magnesium intake decreases the risk of symptomatic nephrolithiasis.
Obstructive uropathy is a structural or functional hindrance of normal urine flow, sometimes leading to renal dysfunction (obstructive nephropathy).
It is a very broad term, and does not imply a location or cause.
The prognosis of hydronephrosis is extremely variable, and depends on the condition leading to hydronephrosis, whether one (unilateral) or both (bilateral) kidneys are affected, the pre-existing kidney function, the duration of hydronephrosis (acute or chronic), and whether hydronephrosis occurred in developing or mature kidneys.
For example, unilateral hydronephrosis caused by an obstructing stone will likely resolve when the stone passes, and the likelihood of recovery is excellent. Alternately, severe bilateral prenatal hydronephrosis (such as occurs with posterior urethral valves) will likely carry a poor long-term prognosis, because obstruction while the kidneys are developing causes permanent kidney damage even if the obstruction is relieved postnatally.
Hydronephrosis can be a cause of pyonephrosis - which is a urological emergency.
Many other complications arise from ureteroceles. Redundant collection systems are usually smaller in diameter than single, and predispose the patient to impassable kidney stones. The effective "bladder within a bladder" compounds this problem by increasing the collision of uric acid particles, the process by which uric acid stones are formed. Ureterocele is also associated with poor kidney function. It can cause frequent blockage of the ureter leading to serious kidney damage. In other cases, a small, upper portion of the kidney is congenitally non-functional. Though often benign, this problem can necessitate the removal of non-functioning parts.
Treatment consists of painkillers and surgical ablation of the dilated vein. This can be accomplished with open abdominal surgery (laparotomy) or keyhole surgery (laparoscopy). Recently, the first robot-assisted surgery was described.
Another approach to treatment involves catheter-based embolisation, often preceded by phlebography to visualise the vein on X-ray fluoroscopy.
Ovarian vein coil embolisation is an effective and safe treatment for pelvic congestion syndrome and lower limb varices of pelvic origin. Many patients with lower limb varices of pelvic origin respond to local treatment i.e. ultrasound guided sclerotherapy. In those cases, ovarian vein coil embolisation should be considered second line treatment to be used if veins recur in a short time period i.e. 1–3 years. This approach allows further pregnancies to proceed if desired. Coil embolisation is not appropriate if a future pregnancy is possible. This treatment has largely superseded operative options.
Coil embolisation requires exclusion of other pelvic pathology, expertise in endovascular surgery, correct placement of appropriate sized coils in the pelvis and also in the upper left ovarian vein, careful pre- and post-procedure specialist vascular ultrasound imaging, a full discussion of the procedure with the patient i.e. informed consent. Complications, such as coil migration, are rare but reported. Their sequelae are usually minor.
If a Nutcracker compression (see below) is discovered, stenting of the renal vein should be considered before embolization of the ovarian vein. Reducing outflow obstruction should always be the main objective.
The aim of treatment is to reduce renal scarring. Those children with grade II or worse should receive low dose prophylactic antibiotics (Nitrofurantoin, trimethoprim, cotrimoxazole, cefalexin in those with CRF). Hypertension should be managed with ACE inhibitor or ARBs. Other treatment modalities include surgery (endoscopic injection of collagen behind the intra-vesical ureter, ureteric re-implantation or lengthening of the submucosal ureteric tunnel) which has its protagonists.
Many women delay treatment for decades. Surgeons often will correct the fistula through major gynecological surgery. Newer treatments can include the placement of a stent and is usually successful. In 0.5-2.5% of major pelvic surgeries a ureterovaginal fistula will form, usually weeks later. If the fistula cannot be repaired, the clinician may create a permanent diversion of urine or urostomy. Risks associated with the repair of the fistula are also associated with most other surgical procedures and include the risk of adhesions, disorders of wound healing, infection, ileus, and immobilization. There is a recurrence rate of 5%–15% in the surgical operation done to correct the fistula.
Renal colic is a type of abdominal pain commonly caused by kidney stones.
There is a genetic predisposition, first-degree relatives have a great increase in the chance of VUR. The gene frequency is estimated to be 1:600. The American Academy of Pediatrics recommends that children from 2 to 24 months presenting with a UTI should be investigated for VUR.
If left untreated, complications may arise including abscess formation, peritonitis, sepsis, and damage to the urinary tract by fibrosis and granuloma formation. It is recommended, as a first step, to drain the lesion with ultrasound or CT guidance. If a patient has an underlying obstructive problem it needs to be addressed according to its cause.
Birth injuries that result in the formation of fistulas and urinary and fecal incontinence have been found to be strongly associated with economic and cultural factors. Teenagers and women who sustain injuries that develop into ureterovaginal fistulas during childbirth suffer significant social stigma. Ureterovaginal fistulas related to prolonged, obstructed labor are rare in developed nations but are more common in countries where access to emergent obstetrical care is limited.
Megaureter is a medical anomaly whereby the ureter is abnormally . Congenital megaureter is an uncommon condition which is more common in males, may be bilateral, and is often associated with other congenital anomalies. The cause is thought to be aperistalsis of the distal ureter, leading to dilatation.
The cutoff value for megaureter is when it is wider than 6 or 7 mm.
A functional obstruction at the lower end of the ureter leads to progressive dilatation and a tendency to infection. The ureteric orifice appears normal and a ureteric catheter passes easily.
Definitive surgical treatment involves refashioning the lower end of the affected ureter so that a tunnelled reimplantation into the bladder can be done to prevent reflux.
Mortality is indirect and caused by complications. After cholangitis occurs, patients typically die within 5–10 years.