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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.
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.
In irrigation test, a lacrimal irrigation cannula is passed into the punctum and advanced through the canaliculus to the lacrimal fossa. Clear water or saline is then irrigated through the cannula. If fluid passes into the nose without reflux out of the opposite canaliculus, the system is patent. If no fluid passes but it all comes back through either punctum, nasolacrimal duct obstruction is present.
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.
Evaluation is in the form of a dye disappearance test followed by irrigation test. By using this sequence (with modifications) as a guide, the physician can frequently streamline diagnostic testing.
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
There is no standardized evaluation of the symptoms of UAB, in part due to the historic terminologic confusion. A thorough history aimed at detecting underlying disease or prior pelvic surgeries is certainly necessary. As a perception of volume mishandling, a voiding diary (to assess voided volumes and frequency of voiding) and a post-void residual volume would be valuable information. Uninstrumented uroflow, neurologic and pelvic examination may contribute valuable information. Imaging looking for abnormal bladder morphology or vesicoureteral reflux/hydronephrosis may be helpful. If low-pressure urine storage can be assured, and the urinary reservoir is known to be limited to the bladder, the general value of urodynamic study in UAB is unclear. In specific situations, invasive urodynamics may be helpful to distinguish bladder outlet obstruction from DU, although this distinction can be difficult.
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.
It is diagnosed by micturating cystography; scarring can be demonstrated by ultrasound or DMSA.
Upon delivery, the exposed bladder is irrigated and a non-adherent film is placed to prevent as much contact with the external environment as possible. In the event the child was not born at a medical center with an appropriate exstrophy support team then transfer will likely follow. Upon transfer, or for those infants born at a medical center able to care for bladder exstrophy, imaging may take place in the first few hours of life prior to the child undergoing surgery.
Primary (immediate) closure is indicated only in those patients with a bladder of appropriate size, elasticity, and contractility as those patients are most likely to develop a bladder of adequate capacity after early surgical intervention.
Conditions that are absolute contraindications despite bladder adequacy include duplication of the penis or scrotum and significant bilateral hydronephrosis.
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.
Once a patient complains of dysphagia they should have an "upper endoscopy" (EGD). Commonly patients are found to have esophagitis and may have an esophageal stricture. Biopsies are usually done to look for evidence of esophagitis even if the EGD is normal. Usually no further testing is required if the diagnosis is established on EGD. Repeat endoscopy may be needed for follow up.
If there is a suspicion of a proximal lesion such as:
- history of surgery for laryngeal or esophageal cancer
- history of radiation or irritating injury
- achalasia
- Zenker's diverticulum
a "barium swallow" may be performed before endoscopy to help identify abnormalities that might increase the risk of perforation at the time of endoscopy.
If achalasia suspected an upper endoscopy is required to exclude a malignancy as a cause of the findings on barium swallow. Manometry is performed next to confirm. A normal endoscopy should be followed by manometry, and if manometry is also normal, the diagnosis is functional dysphagia.
Therapy for UAB is often dependent on factors such as age, health, symptoms, and cause of the condition. Treatment frequently includes lifestyle modification (fluid restriction, bladder retraining). Bethanechol is a prescription medication used for treatment, bethanechol can stimulate the nerves of the bladder, making them more responsive to stimulus. With UAB, it is common for patients to utilize a urinary catheter to void. Surgical options are also options, with a cuff or stent placed around or in the neck of the bladder to aid the emptying and leakage of urine. Neuromodulatory techniques such as sacral nerve or posterior tibial nerve stimulation may be of value in selected cases. However, current therapies are considered inadequate and there is a strong need for new research and attention.(Van Koeveringe et al., 2011; Tyagi et al. 2015).
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.
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.
In a small retrospective study of 25 pregnancies five factors were found to be strongly associated with a prenatal diagnosis of bladder exstrophy:
- Inability to visualize the bladder on ultrasound
- A lower abdominal bulge
- A small penis with anteriorly displaced scrotum
- A low set umbilical insertion
- Abnormal widening of the iliac crests
While a diagnosis of bladder exstrophy was made retrospectively in a majority of pregnancies, in only three cases was a prenatal diagnosis made.
It can be diagnosed with an X-ray while the patient swallows barium (called a barium study of the esophagus), by a computerized tomography scan, a biopsy, or by an endoscopy.
The patient is generally sent for a GI, pulmonary, or ENT, depending on the suspected underlying cause. Consultations with a speech therapist and registered dietitian nutritionist (RDN) are also needed, as many patients may need dietary modifications such as thickened fluids.
If a kidney stone is suspected (e.g. on the basis of characteristic colicky pain or the presence of a disproportionate amount of blood in the urine), a kidneys, ureters, and bladder x-ray (KUB film) may assist in identifying radioopaque stones. Where available, a noncontrast helical CT scan with 5 millimeter sections is the diagnostic modality of choice in the radiographic evaluation of suspected nephrolithiasis. All stones are detectable on CT scans except very rare stones composed of certain drug residues in the urine. In patients with recurrent ascending urinary tract infections, it may be necessary to exclude an anatomical abnormality, such as vesicoureteral reflux or polycystic kidney disease. Investigations used in this setting include kidney ultrasonography or voiding cystourethrography. CT scan or kidney ultrasonography is useful in the diagnosis of xanthogranulomatous pyelonephritis; serial imaging may be useful for differentiating this condition from kidney cancer.
Ultrasound findings that indicate pyelonephritis are enlargement of the kidney, edema in the renal sinus or parenchyma, bleeding, loss of corticomedullary differentiation, abscess formation, or an areas of poor blood flow on doppler ultrasound. However, ultrasound findings are seen in only 20% to 24% of people with pyelonephritis.
A DMSA scan is a radionuclide scan that uses dimercaptosuccinic acid in assessing the kidney morphology. It is now the most reliable test for the diagnosis of acute pyelonephritis.
Analysis of the urine may show signs of urinary tract infection. Specifically, the presence of nitrite and white blood cells on a urine test strip in patients with typical symptoms are sufficient for the diagnosis of pyelonephritis, and are an indication for empirical treatment. Blood tests such as a complete blood count may show neutrophilia. Microbiological culture of the urine, with or without blood cultures and antibiotic sensitivity testing are useful for establishing a formal diagnosis, and are considered mandatory.
Since it is a rare disease, it remains a diagnosis of exclusion of other conditions with similar symptoms. The diagnosis is supported by the results of imaging studies such as computed tomography or magnetic resonance imaging, ultrasound of the abdomen (with or without doppler imaging) or intravenous urography.
Specialist vascular ultrasonographers should routinely look for left ovarian vein reflux in patients with lower limb varices especially if not associated with long or short saphenous reflux. The clinical pattern of varices differs between the two types of lower limb varices.
CT scanning is used to exclude abdominal or pelvic pathology. CT-Angiography/Venography can often demonstrate left ovarian vein reflux and image an enlarged left ovarian vein but is less sensitive and much more expensive than duplex Doppler ultrasound examination. Ultrasound requires that the ultrasonographer be experienced in venous vascular ultrasound and so is not always readily available. A second specialist ultrasound exam remains preferable to a CT scan.
As a wide range of pelvic and abdominal pathology can cause symptoms consistent with those symptoms due to left ovarian vein reflux, prior to embolisation of the left ovarian vein, a careful search for such diagnoses is essential. Consultation with general surgeons, gynaecologists, and possibly CT scanning should always be considered.
Screening tools for contact granulomas are not currently available. Diagnosis of contact granulomas require visualization using laryngoscopy, and may require further biopsy for differential diagnosis. A combination of symptoms and lifestyle factors may be linked with the development of a contact granuloma, however symptoms vary greatly by individual. Some lifestyle factors that have been linked with elevated risk of development of contact granulomas include frequent use of the voice, especially when in loud environments, and concurrent use of the voice with alcohol consumption (increasing risk of gastroesophageal reflux symptoms). Contact granuloma may also arise after intubation, and so following intubation, patients should be monitored if voice symptoms arise. Symptoms may or may not include hoarse voice, described as "huskiness" by some patients, "aching" in the throat related to increased effort to produce voice, and the feeling of having a lump in one's throat when swallowing. It is also possible to have no such symptoms, especially if the granuloma is small. A patient presenting with such symptoms or risk factors should therefore be referred for further visualization. It is therefore recommended to obtain a diagnosis from a doctor.
MCDK is usually diagnosed by ultrasound examination before birth. Mean age at the time of antenatal diagnosis is about 28 weeks A microscopic analysis of urine in individuals with probable multicystic dysplastic kidney should be done. One meta-analysis demonstrated that unilateral MCDK occurs more frequently in males and the greater percentage of MCKD occur on the left side of the body.
If it is caused by esophagitis, in turn caused by an underlying infection, it is commonly treated by treating the infection (typically with antibiotics). In order to open the stricture, a surgeon can insert a bougie – a weighted tube used to dilate the constricted areas in the esophagus. It can sometimes be treated with other medications. For example, an H2 antagonist (e.g. ranitidine) or a proton-pump inhibitor (e.g. omeprazole) can treat underlying acid reflux disease.