Kidneys play a vital role for the human body. The kidneys act as a filter, as they control chemicals that are introduced to the body and regulate the urine that will be excreted. “The kidneys must filter all blood, remove waste products, reabsorb selected substances needed by the body, and secrete what is not needed by the body in the form of urine” (Linn-Watson,2014). The urinary system consists of two kidneys, each of which is connected to the bladder by a ureter. The urine flows from the kidneys, to the bladder via the ureters.
Then from the bladder, the urine is excreted from the body by the urethra. This process can be very simple, but when there are pathologies present the process becomes complicated. Duplex collecting systems is the main topic and how it may become complicated by vesicoureteral reflux (VUR) and ureterocele will be covered in this paper. Duplex collecting system, also known as double ureters, happens to be one of the most common congenital anomalies (Linn-Watson, 2014). In a normal kidney, there is only one ureter to drain each of the kidneys.
In a duplex collecting system, one or both of the kidneys may have two ureters draining the kidney rather than just one. With two ureters there is a mid-pole that drains the majority of the kidney and an upper-pole that only drains the upper portion of the kidney. Most times it is seen unilaterally and occurs mainly in females (Smith, 2013). There are two types of duplex collecting systems known, these include: complete separate ureters or incomplete ureters known as a Y type. According to Smith (2013), an incomplete type is from early branching of the ureteral bud before it meets with the metanephric blastemal.
When this type is seen during a study, it will appear as two ureters descending from the kidney and sometime before it joins the bladder, the two ureters join as one. Whereas the complete type happens when two ureteral buds form two completely different ureters and renal pelvis’ (Smith, 2013). When imaging this type of duplication, the two ureters can be followed from the kidneys all the way to the bladder, staying completely separate and never joining. Double ureters do not typically present any signs so it is a possibility that this condition might go undiagnosed.
CLINICAL INDICATIONS: Most patients are with a duplex collecting system are asymptomatic (Kogan, 2013). Depending on the severity of the pathology; presentation of chronic urinary tract infections, incontinence, and flank pain may be indicators of ureter duplication (Davda, 2013). “Complete duplication can be complicated by obstruction or by vesicoureteral reflux with infection” (Eisenberg, 220). Urine should flow one way; it should descend from the kidneys to the bladder where it then should exit the body.
A complication of double ureters is when urine backflows from the bladder back up into the kidneys; this is known as vesicoureteral reflux or VUR (Estrada, 2015). VUR and infection are most often found in the in the mid-pole ureter that drains the lower portion of the kidney (Eisenburg, pp. 220). Another complication that may be found in double ureters is an ureterocele. A ureterocele occurs at the terminal portion of the ureter where is joins the bladder. It is caused by a cystic dilation that hinders the orifice (Kliegman, 2016).
When accompanying a double ureter, the ureterocele is found on the ureter that drains the upper renal portion. Due to congenital obstructions that may be a result of a mass or ureterocele, the upper portion of the kidney usually functions poorly or is dysplastic (Kliegman, 2016). DIAGNOSIS: Duplex ureters may be identified using many different procedures. A common procedure that presents great information and allows us to view the upper urinary tract along with the bladder is a voiding cystourethrography (VCUG). During a VCUG, catheterization via the urethra will allow for administration of contrast in a retro-grade fashion.
The contrast will be watched as it enters the bladder and is voided by the patient under fluoroscopy. A simple IVU/IVP, cystogram, sonography exam, or a nuclear medicine study called Radionuclide may allow vesicoureteral reflux to be detected (Tanagho, 2013). Ureteroceles are usually caught during sonography exams or VCUG procedures as well. According to Gatti (2015), duplicated ureters, VUR and ureteroceles can also be seen during embryonic growth with the help of ultrasonography. RADIOGRAPHIC MANIFESTATIONS: A duplicated ureter simply looks like an extra ureter when highlighted with contrast media.
The contrast media allows the ureter to be seen and identify any obstructions or complications that may be present. During contrast exams, ureteroceles may appear differently depending on their status. According to Elsenberg (2015), if the lesion fills with contrast, it will appear round-like with a think radiolucent ring surrounding it. That thin line signifies the wall of the prolapsed ureter (Elsenberg, 2015). If the lesion does not fill with contrast, it will simply resemble a radiolucent mass surrounded by contrast in the ureter orifice (Elsenberg, 2015).
Ultrasound also may be used to image ureteroceles as they only appear as circular cyst in the bladder (Elsenberg, 2015). Based on a voiding cystogram, vesicoureteral reflux appears differently at each level. In level one, the renal pelvis appears normal with sharp calyces as the urine is only backing up in the ureter. Level two, the renal pelvis appears the same; the urine now backs up into the ureter, and the renal pelvis. With level three the ureter and renal pelvis begin to dilate and the calyces are mildly blunted as the urine backs up into the ureter and collecting system.
Level 4, the urine is still backing up into the ureter and collecting system, causing the ureter and renal pelvis to appear moderately dilated with discreetly blunted calyces. In the last level of VUR, the renal pelvis is severely dilated, ureter appears tortuous with severely blunted calyces from the urine backing up into the ureter and collecting system (Estrada, 2015). RISK FACTORS: As a duplicate ureter is usually asymptomatic, most of the risk factors come from predisposing factors like VUR and ureteroceles. Most times VUR is associated with urinary tract infection, hydronephrosis, and or abnormal kidney development.
A patient that is experiencing VUR should be monitored while they are getting treatment. If the reflux does not show signs of improvement, surgery will be explored in an attempt to help the patient (Estrada, 2015). If the patient does not receive treatment, permanent damage can be done to the patient’s urinary system by one or both of two mechanisms, pyelonephritis and hydroureteronephrosis (Tanagho, 2013). Pyelonephritis is the inflammation of the interstitial tissue between the tubes caused by a pyogenic bacterium and hydroureteronephrosis is when the ureter and kidney are dilated (Elsenberg, 2015).
TREATMENT: Treatment is pretty simple for duplex collecting system. As it is a congenital anomaly, most times no treatment is needed (Elsenberg, 2015). If an obstruction or complications occur, such as reflux or ureteroceles; the predisposing factors are treated first before looking into treatment for duplicated ureters. This may be done by the means of antibiotic therapy or surgery (Elsenberg, 2015). With VUR, there are 5 levels of reflux and depending on which level the patient falls into, determines the treatment that is needed (Estrada, 2015).
Lower grades of VUR are usually taken care of with medication or may resolve on its own (Elsenberg, 2015). However, the higher grades of VUR almost always need to have surgically intervention (Kogan, 2013). A low grade of vesicoureteral reflux may dissolve without any medical attention (Kliegmen, 2016). For most cases antibiotics are used to treat the infection caused by low grades of VUR. In the event surgical intervention is needed to treat VUR, a number of things must be considered to pick the right operation for the patient (Gatti, 2015).
Factors of the age of the patient, percentage of functioning parenchyma, intravesical versus extravesical ureterocele, detrusor backing, degree of ureteral dilation, presence of reflux and the number of moieties involved are considered when choosing the correct operation (Gatti, 2015). Operations such as Pyeloueterostomy, Ureteroureterostomy or Ureteral re-implantation may be performed in efforts to save the renal parenchyma (Kogan, 2013). If one portions of the kidney is functioning poorly, then a heminephrectomy may be appropriate to remove that portion (Kogan, 2013).
An incision at the vesicoureteral junction can be done endoscopically, in which will drain the ureterocele and allow the urine to drain as normal to the bladder (Elsenberg, 2015). For the presence of a severe ureterocele, an open operation may have to take place. An open operation may be a Heminephrectomy, which is removing part of the kidney and Ureterectomy, which is removing part of the ureter. Any treatment provided should also be monitored to insure it was the correct treatment plan (Kogan, 2013). PROGNOSIS: Overall the prognosis of duplicated ureters is very good.
Patients are known to live normal lives with minimal to no complications with this congenital anomaly. If complications of VUR or ureteroceles are not treated, the prognosis outcome may be different. It is critical to select the correct treatment plan per the patient, as permanent kidney damage can occur. STAT BACKUP: It is stated that about 1 in 125 children have duplicated ureters, in which 80% are female and are 2-3 years old when diagnosed (Kliegmen, 2016). VUR occurs in only 8% of adults with bacterium, and 20-40% of children with constant urinary tract infections (Tanagho, 2013).
Children with ureteral duplication have and 80% incidence of an associated ureterocele” (Elsenberg, 2015), almost always present in girls, but only 50% of affected boys only have 1 ureter (Kliegman, 2016). CASE STUDY: The case study started patient that came to the Altamonte Outpatient imaging center for a contrast IVP exam. The patient complained of being sore and being mildly uncomfortable during the exam. With review of the radiologist report it stated had a unilateral duplex collecting system (Farley, 2015).
The pathology occurred on the left side, where the patients left kidney was mildly enlarged measuring 14cm long (Farley, 2015). Both ureters were imaged leaving the kidney and disappeared after the level of L4 (Farley, 2015). At the level of L4, the ureters did not opacify with contrast (Farley, 2015). Dr. Farley stated that the right kidney was of normal size with a normal collecting system and no signs of hyfronephrosis. Also, the bladder was of normal size and there was no evidence of filling defects or significant post-void lingering (Farley, 2015).
CONCLUSION: In conclusion, duplicated ureters may not be a serious issue at first, but can pose a threat to healthy kidneys. This pathology may be seen on a wide variety of test such as a IVP or a VCUG, as well as using different modalities such as radiography and ultrasound. As seen with this case study patient, one can live with duplicated ureters but may experience some complications of pain, inconsistence and urinary tract infections (Davda, 2013). If the inconsistence and infection is not treated for might lead to Pyelonephritis, and result in kidney function impairment.