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The younger the patient and the lower the grade at presentation the higher the chance of spontaneous resolution. Approximately 85% of grade I & II VUR cases will resolve spontaneously. Approximately 50% of grade III cases and a lower percentage of higher grades will also resolve spontaneously.
The following procedures may be used to diagnose VUR:
- Cystography
- Fluoroscopic voiding cystourethrogram (VCUG)
- Abdominal ultrasound
- Technetium-99m Dimercaptosuccunic Acid (DMSA) Scintigraphy
An abdominal ultrasound might suggest the presence of VUR if ureteral dilatation is present; however, in many circumstances of VUR of low to moderate, even high severity, the sonogram may be completely normal, thus providing insufficient utility as a single diagnostic test in the evaluation of children suspected of having VUR, such as those presenting with prenatal hydronephrosis or urinary tract infection (UTI).
VCUG is the method of choice for grading and initial workup, while RNC is preferred for subsequent evaluations as there is less exposure to radiation. A high index of suspicion should be attached to any case where a child presents with a urinary tract infection, and anatomical causes should be excluded. A VCUG and abdominal ultrasound should be performed in these cases
DMSA scintigraphy is used for the evaluation of the paranchymal damage, which is seen as cortical scars. After the first febrile UTI, the diagnostic role of an initial scintigraphy for detecting the damage before the VCUG was investigated and it was suggested that VCUG can be omitted in children who has no cortical scars and urinary tract dilatation.
Early diagnosis in children is crucial as studies have shown that the children with VUR who present with a UTI and associated acute pyelonephritis are more likely to develop permanent renal cortical scarring than those children without VUR, with an odds ratio of 2.8. Thus VUR not only increases the frequency of UTI's, but also the risk of damage to upper urinary structures and end-stage renal disease.
Abdominal ultrasound is of some benefit, but not diagnostic. Features that suggest posterior urethral valves are bilateral hydronephrosis, a thickened bladder wall with thickened smooth muscle trabeculations, and bladder diverticula.
Voiding cystourethrogram (VCUG) is more specific for the diagnosis. Normal "plicae circularis" are variable in appearance and often not seen on normal VCUGs. PUV on voiding cystourethrogram is characterized by an abrupt tapering of urethral caliber near the verumontanum, with the specific level depending on the developmental variant. Vesicoureteral reflux is also seen in over 50% of cases. Very often the posterior urethra maybe dilated thus making the abrupt narrowing more obvious. the bladder wall may show trabeculations or sacculations or even diverticuli.
Diagnosis can also be made by cystoscopy, where a small camera is inserted into the urethra for direct visualization of the posteriorly positioned valve. A limitation of this technique is that posterior valve tissue is translucent and can be pushed against the wall of the urethra by inflowing irrigation fluid, making it difficult to visualize. Cystoscopy may also demonstrate the bladder changes.
Centers in Europe and Japan have also had excellent results with cystosonography, although it has not been approved for use in the United States yet.
Urethral diverticulum is often an incidental finding. It can be diagnosed using magnetic resonance imaging and/or micturating cystourethrography. Other studies that can be used to diagnose urethral diverticulum include intravenous urography, urethroscopy, and/or ultrasound. Conditions that should be distinguished from urethral diverticulum in a differential diagnosis include overactive bladder, Gartner's duct cyst, Gartner's duct abscess, ectopic caeco-ureterocele, interstitial cystitis, pelvic inflammatory disease, endometriosis, and cancer.
No useful studies have been done to determine whether acupuncture can help people with stress urinary incontinence.
At the present time, there is one temporary prostatic stent that has received U.S. Food and Drug Administration (FDA) approval. The Spanner
temporary prostatic stent maintains urine flow and allows natural voluntary urination. The prostatic stent is a completely internal device and can be inserted and removed as easily as a Foley catheter. It permits normal bladder and sphincter functioning and can be worn comfortably by patients. The temporary prostatic stent is typically used to help patients maintain urine flow after procedures that cause prostatic swelling, such as brachytherapy, cryotherapy, TUMT, TURP. It has also become an effective differential diagnostic tool for identifying poor bladder function separate from prostatic obstruction.
Diagnosis is based on results of bladder catheterization, ultrasonography, CT scan, cystourethroscopy, or pyelography, depending on the level of obstruction.
The Gold standard for all Urinary incontinence is an urodynamic study that looks for bladder capacity, detrusor stability, contractility and voiding ability (Cystometry)
Diagnosis is by rectal examination. A specialized tool called a "Perineocaliper" can be used to measure the descent of the perineum. A retro anal ultrasound scan may demonstrate the condition. "Anti sagging tests", whereby the abnormal descent is corrected temporarily, may help to show whether symptoms are due to descending perineum syndrome or are in fact due to another condition.
Normally, the anal margin lies just below a line drawn between the coccyx (tailbone) and the pubic symphysis. In descending perineum syndrome the anal canal is situated several cm below this imaginary line, or it descends 3–4 cm during straining.
Defecography may also demonstrate abnormal perineal descent.
Imaging studies, such as an intravenous urogram (IVU), renal ultrasonography, CT or MRI, are also important investigations in determining the presence and/ or cause of hydronephrosis. Whilst ultrasound allows for visualisation of the ureters and kidneys (and determine the presence of hydronephrosis and / or hydroureter), an IVU is useful for assessing the anatomical location of the obstruction. Antegrade or retrograde pyelography will show similar findings to an IVU but offer a therapeutic option as well. Real-time ultrasounds and Doppler ultrasound tests in association with vascular resistance testing helps determine how a given obstruction is effecting urinary functionality in hydronephrotic patients.
In determining the cause of hydronephrosis, it is important to rule out urinary obstruction. One way to do this is to test the kidney function. This can be done by, for instance, a diuretic intravenous pyelogram, in which the urinary system is observed radiographically after administration of a diuretic, such as 5% mannitol, and an intravenous iodine contrast. The location of obstruction can be determined with a Whittaker (or pressure perfusion) test, wherein the collecting system of the kidney is accessed percutaneously, and the liquid is introduced at high pressure and constant rate of 10ml/min while measuring the pressure within the renal pelvis. A rise in pressure above 22 cm HO suggests that the urinary collection system is obstructed. When arriving at this pressure measurement, bladder pressure is subtracted from the initial reading of internal pressure. (The test was first described by Whittaker in 1973 to test the hypothesis that patients' whose hydronephrosis persists after the posterior urethral valves have been ablated usually have ureters that are not obstructed, even though they may be dilated.)
Kay recommends that a neonate born with untreated in utero hydronephrosis receive a renal ultrasound within two days of birth. A renal pelvis greater than 12mm in a neonate is considered abnormal and suggests significant dilation and possible abnormalities such as obstruction or morphological abnormalities in the urinary tract.
The choice of imaging depends on the clinical presentation (history, symptoms and examination findings). In the case of renal colic (one sided loin pain usually accompanied by a trace of blood in the urine) the initial investigation is usually a spiral or helical CT scan. This has the advantage of showing whether there is any obstruction of flow of urine causing hydronephrosis as well as demonstrating the function of the other kidney. Many stones are not visible on plain X-ray or IVU but 99% of stones are visible on CT and therefore CT is becoming a common choice of initial investigation. CT is not used however, when there is a reason to avoid radiation exposure, e.g. in pregnancy.
For incidentally detected prenatal hydronephrosis, the first study to obtain is a postnatal renal ultrasound, since as noted, many cases of prenatal hydronephrosis resolve spontaneously. This is generally done within the first few days after birth, although there is some risk that obtaining an imaging study this early may miss some cases of mild hydronephrosis due to the relative oliguria of a newborn. Thus, some experts recommend obtaining a follow up ultrasound at 4–6 weeks to reduce the false-negative rate of the initial ultrasound. A voiding cystourethrogram (VCUG) is also typically obtained to exclude the possibility of vesicoureteral reflux or anatomical abnormalities such as posterior urethral valves. Finally, if hydronephrosis is significant and obstruction is suspected, such as a ureteropelvic junction (UPJ) or ureterovesical junction (UVJ) obstruction, a nuclear imaging study such as a MAG-3 scan is warranted.
Bethanechol (Management of overflow incontinence by activating muscarinic receptors in the bladder and stimulating contraction to void the urine, NOT a treatment modality; must rule out urinary obstruction prior to use.)
If an incontinence is due to overflow incontinence, in which the bladder never empties completely, or if the bladder cannot empty because of poor muscle tone, past surgery, or spinal cord injury, a catheter may be used to empty the bladder. A catheter is a tube that can be inserted through the urethra into the bladder to drain urine. Catheters may be used once in a while or on a constant basis, in which case the tube connects to a bag that is attached to the leg. If a long-term (or indwelling) catheter is used, urinary tract infections may occur.
Urinary catheters should be inserted using aseptic technique and sterile equipment (including sterile gloves, drape, sponges, antiseptic and sterile solution), particularly in an acute care setting. Hands should be washed before and after catheter insertion. Overall, catheter use should be minimized in all patients, particularly those at higher risk of CAUTI and mortality (e.g. the elderly or those with impaired immunity).
Permanent stents are often metal coils, which are inserted into the male urethra. The braided mesh is designed to expand radially, applying constant gentle pressure to hold open the sections of the urethra that obstruct the flow of urine. The open, diamond-shape cell design of the stent allows the stent to eventually become embedded in the urethra, thus minimizing the risk for encrustation and migration. Permanent stents are used to relieve urinary obstructions secondary to benign prostatic hyperplasia (BPH), recurrent bulbar urethral stricture (RBUS), or detrusor external sphincter dyssynergia (DESD). The main motive for removal of permanent stents is worsening of symptoms even with device fitted. Other reasons have been migration, clot retention, hematuria, and urinary retention. The only FDA approved permanent stent is the Urolume. Usually, permanent stents are used only for men who are unwilling or unable to take medications or who are reluctant or unable to have surgery. Most doctors do not consider permanent stents a viable long-term treatment for most men.
The diagnosis of bladder stone includes urinalysis, ultrasonography, x rays or cystoscopy (inserting a small thin camera into the urethra and viewing the bladder). The intravenous pyelogram can also be used to assess the presence of kidney stones. This test involves injecting a radiocontrast agent which is passed into the urinary system. X-ray images are then obtained every few minutes to determine if there is any obstruction to the contrast as it is excreted into the bladder. Today, intravenous pyelogram has been replaced at many health centers by CT scans. CT scans are more sensitive and can identify very small stones not seen by other tests.
In rare cases, a surgeon implants an artificial urinary sphincter, a doughnut-shaped sac that circles the urethra. A fluid fills and expands the sac, which squeezes the urethra closed. By pressing a valve implanted under the skin, the artificial sphincter can be deflated. This removes pressure from the urethra, allowing urine from the bladder to pass.
The Society of Fetal Ultrasound has developed a grading system for hydronephrosis, initially intended for use in neonatal and infant hydronephrosis, but it is now used for grading hydronephrosis in adults as well:
- Grade 0 – No renal pelvis dilation. This means an anteroposterior diameter of less than 4 mm in fetuses up to 32 weeks of gestational age and 7 mm afterwards. In adults, cutoff values for renal pelvic dilation have been defined differently by different sources, with anteroposterior diameters ranging between 10 and 20 mm. About 13% of normal healthy adults have a transverse pelvic diameter of over 10 mm.
- Grade 1 (mild) – Mild renal pelvis dilation (anteroposterior diameter less than 10 mm in fetuses) without dilation of the calyces nor parenchymal atrophy
- Grade 2 (mild) – Moderate renal pelvis dilation (between 10 and 15 mm in fetuses), including a few calyces
- Grade 3 (moderate) – Renal pelvis dilation with all calyces uniformly dilated. Normal renal parenchyma
- Grade 4 (severe) – As grade 3 but with thinning of the renal parenchyma
Jackstone calculi are rare bladder stones that have an appearance resembling toy jacks. They are almost always composed of calcium oxalate dihydrate and consist of a dense central core and radiating . They are typically light brown with dark patches and are usually formed in the urinary bladder and rarely in the upper urinary tract. Their appearance on plain radiographs and computed tomography in human patients is usually easily recognizable. Jackstones often must be removed via cystolithotomy.
Urinary tract obstruction as a congenital disorder results in oligohydramnios which in turn can lead to the Potter sequence of atypical physical appearance. Pulmonary hypoplasia is by far the main cause of death in the early neonatal period for children with congenital lower urinary tract obstruction.
Fetal surgery of congenital lower urinary tract obstruction seems to improve survival, according to a randomized yet small study.
An imperforate hymen is most often diagnosed in adolescent girls after the age of menarche with otherwise normal development. In adolescent girls of menarcheal age, the typical presentation of the condition is amennorhea and cyclic pelvic pain, indicative of hematocolpos secondary to vaginal obstruction. An imperforate hymen is usually visible on vaginal inspection as a bulging blue membrane. If hematocolpos is present, a mass is often palpable on abdominal or rectal examination. The diagnosis of an imperforate hymen is usually made based purely on the physical exam, although if necessary the diagnosis can be confirmed by transabdominal, transperineal or transrectal ultrasound.
An imperforate hymen can also be diagnosed in newborn babies and it is occasionally detected on ultrasound scans of the foetus during pregnancy. In newborns the diagnosis is based on the findings of an abdominal or pelvic mass or a bulging hymen. Examination of the normal neonatal vagina usually reveals a track of mucus at the posterior commissure of the labia majora; an absence of mucus may indicate an imperforate hymen or another vaginal obstruction.
A similar condition, cribriform hymen, is diagnosed when the hymen contains many minute openings.
A meta-analysis on the influence of voiding position on urodynamics in healthy males and males with LUTS showed that in the sitting position, the residual urine in the bladder was significantly reduced. The other parameters, namely the maximum urinary flow and the voiding time were increased and decreased respectively. For healthy males, no influence was found on these parameters, meaning that they can urinate in either position.
The primary treatment for urethral diverticulum is surgical. The surgery is conducted transvaginally, usually when there is no acute inflammation to better aid dissection of the delicate tissues.
If suspected antenatally, a consultation with a paediatric surgeon/ paediatric urologist maybe indicated to evaluate the risk and consider treatment options.
Treatment is by endoscopic valve ablation. Fetal surgery is a high risk procedure reserved for cases with severe oligohydramnios, to try to limit the associated lung underdevelopment, or pulmonary hypoplasia, that is seen at birth in these patients. The risks of fetal surgery are significant and include limb entrapment, abdominal injury, and fetal or maternal death. Specific procedures for "in utero" intervention include infusions of amniotic fluid, serial bladder aspiration, and creating a connection between the amniotic sac and the fetal bladder, or vesicoamniotic shunt.
There are three specific endoscopic treatments of posterior urethral valves:
- Vesicostomy followed by valve ablation - a stoma, or hole, is made in the urinary bladder, also known as "low diversion", after which the valve is ablated and the stoma is closed.
- Pyelostomy followed by valve ablation - stoma is made in the pelvis of the kidney as a slightly "high diversion", after which the valve is ablated and the stoma is closed
- Primary (transurethral) valve ablation - the valve is removed through the urethra without creation of a stoma
The standard treatment is primary (transurethral) ablation of the valves. Urinary diversion is used in selected cases, and its benefit is disputed.
Following surgery, the follow-up in patients with posterior urethral valve syndrome is long term, and often requires a multidisciplinary effort between paediatric surgeons/ paediatric urologists, pulmonologists, neonatologists, radiologists and the family of the patient. Care must be taken to promote proper bladder compliance and renal function, as well as to monitor and treat the significant lung underdevelopment that can accompany the disorder. Definitive treatment may also be indicated for the vesico-ureteral reflux.
Biochemical blood tests determine the amount of typical markers of renal function in the blood serum, for instance serum urea and serum creatinine. Biochemistry can also be used to determine serum electrolytes. Special biochemical tests (arterial blood gas) can determine the amount of dissolved gases in the blood, indicating if pH imbalances are acute or chronic.
Urinalysis is a test that studies urine for abnormal substances such as protein or signs of infection.
- A Full Ward Test, also known as dipstick urinalysis, involves the dipping of a biochemically active test strip into the urine specimen to determine levels of tell-tale chemicals in the urine.
- Urinalysis can also involve MC&S microscopy, culture and sensitivity
Urodynamic tests evaluate the storage of urine in the bladder and the flow of urine from the bladder through the urethra. It may be performed in cases of incontinence or neurological problems affecting the urinary tract.
Ultrasound is commonly performed to investigate problems of the kidney and/or urinary tract.
Radiology:
- KUB is plain radiography of the urinary system, e.g. to identify kidney stones.
- An intravenous pyelogram studies the shape of the urinary system.
- CAT scans and MRI can also be useful in localising urinary tract pathology.
- A voiding cystogram is a functional study where contrast "dye" is injected through a catheter into the bladder. Under x-ray the radiologist asks the patient to void (usually young children) and will watch the contrast exiting the body on the x-ray monitor. This examines the child's bladder and lower urinary tract. Typically looking for vesicoureteral reflux, involving urine backflow up into the kidneys.
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:
Surgical treatments may be used to treat the condition, and include retro-rectal levatorplasty, post-anal repair, retro-anal levator plate myorrhaphy.