The importance of VUR in adults is debatable. However, in patients with neurogenic bladder and reconstructed bladders it may be important to treat. New or worsening VUR can indicate worsening bladder compliance and a need for re-evaluation of pressures with a cystometrogram (urodynamics) (Fig. 9.3). VUR may complicate UTI because otherwise asymptomatic bacteriuria may ascend and cause febrile UTI and systemic symptoms. A large and dilated refluxing system may also act as a reservoir of static urine, where infection can arise. Some studies show that augmentation cystoplasty alone resolves or downgrades nearly all VUR in both adult and pediatric populations by restoring a low-pressure system [29–31]. These findings are controversial, however, and some recent studies have found opposite results. In one study of children undergoing augmentation cystoplasty with small bowel, low-grade VUR persisted in only 10 % of patients, however, high-grade VUR persisted in 47 %, and about half of these patients went on to experience pyelonephritis if they did not have treatment of VUR at the time of augmentation cystoplasty [32]. Conversely, patients who undergo ureteral re-implantation at the time of augmentation cytsoplasty were found to have complete resolution of high-grade VUR and a markedly decreased incidence of UTI [33]. Based upon these findings, authors recommended, ureteral re-implantation for high-grade VUR at the time of augmentation cystoplasty. Interpreting these contradictory results is difficult, however, and consideration should be given to the fact that treating VUR with ureteral re-implantation after augmentation is a much harder task than at the time of augmentation cystoplasty.

In follow-up regimens of patients with neurogenic bladder, it is often argued that patients should have annual or regular cystograms to monitor for VUR. This recommendation may be unnecessary since there is very little data to support treatment of VUR in asymptomatic adults, other than for evidence of ascending infections that cause pyelonephritis episodes. A targeted approach in individuals who are having febrile UTI or evidence of pyelonephritis will save patients from many unnecessary cystograms and associated risks, such as induction of urosepsis or catheter trauma.

Lapides popularized the concept that high intravesical pressure and bladder over distention is responsible for increased UTI risk. The postulated mechanism is that when the bladder is subjected to periods of reduced blood flow, its susceptibility to bacterial invasion is increased [34]. There is a substantial amount of indirect evidence supporting this theory. For instance, urodynamic testing in infants with UTI but without VUR showed high voiding detrusor pressures of 40–100 cm, suggesting that the high-pressure voiding itself, rather than an anatomic defect, predisposed these infants to UTI [35].

The link between high-pressure voiding and UTI is further illustrated by a decrease in the incidence of UTI through interventions that increase bladder capacity and decrease detrusor tone. For example, surgical release of spinal cord tethering has been found to increase bladder capacity and decrease detrusor leak point pressures, with a corresponding drop in febrile UTI [36]. Similarly, improved bladder capacity and decreased bladder pressures observed in patients with sacral nerve modulator implants, placed immediately after SCI, and has also been associated with a decreased incidence of UTI [37]. Other evidence supporting this concept is in patients with neurogenic detrusor overactivity due to multiple sclerosis (MS) or SCI who received detrusor injections of 300 U of onabotulinum toxinA. In this study, the number of UTIs over 6 months decreased from a mean of 1.75 to 0.2. Interestingly, those patients with persistent symptomatic urinary infections also demonstrated less improvement in their urodynamic parameters, reflecting the idea that improved reservoir capacity and lower pressures are protective against UTI [38]. In contrast to this study, however, it is important to note that UTI risk was higher in patients treated onabotulinum toxinA, in the DIGNITY trial. This increased risk was likely due to patients with MS starting intermittent catheterization. As part of the same study, the patients with SCI who were already performing catheterization did not have a decrease in UTI, but UTI was only defined as positive cultures, which were routinely obtained during follow-up and there was no quantification of symptomatic UTI.

When compliance is felt to be a major issue, then a urodynamic study (cystometrogram) is warranted. Even in patients with previous bladder augmentation a low capacity and poor compliance bladder may be an issue. In fact, up to 9 % of patients with a history of pediatric augmentation cystoplasty require re-augmentation [25, 26, 39]. A bladder journal documenting the patient’s functional volumes can also provide vital information about their capacity and identify patients who might benefit from urodynamics.

Among patients who have undergone bladder reconstruction, in particular augmentation cystoplasty, 34–40 % can be expected to require an additional urological procedure in the future. The most common surgery is cystolithalopaxy, accounting for 25 % of interventions post-augmentation, with a median of two occurrences of stones [25, 26]. In regard to major revision surgery, urinary diversion is required in 5 %, repair of bladder rupture in 3 %, treatment of small bowel obstruction in 3 %, and re-augmentation in 9 % due to issues with persistent incontinence, isolated upper tract changes, and detrusor pressure of >30 cmH₂O [25, 26, 39]. Revision rates for a catheterizable channel have also been reported to be as high as 20 % [40], and in our experience up to 50 % of patients require revision surgery for tunneled catheterizable channels [21]. While many of these operative problems do not lead to increasing UTI, they serve to emphasize that anatomic problems which need to be addressed with surgery are commonplace after bladder reconstruction.

When UTI begin or worsen in patients with previous bladder reconstruction or augmentation, it is important to fully evaluate any anatomic reasons that could be contributing. One of the most important considerations is kidney obstruction from previous ureteral surgery. While ureteral re-implant surgery to treat VUR has a very low stenosis rate long term, this may not be true in neurogenic bladder patients. The neurogenic bladder is fundamentally quite different; it is thickened and fibrotic, lacking normal elasticity and may have been adversely affected by years of chronic cystitis. All of these factors can lead to recurrent VUR or stenosis. As mentioned above, VUR can be a cause of febrile UTI in patients due to pyelonephritis and is evaluated with a cystogram. Ureteral stenosis is evaluated with a nuclear medicine lasix renogram. It is often difficult to interpret the results of lasix renograms, however, given that many patients who have had chronic hydronephrosis may exhibit some degree of delayed emptying. In cases that are equivocal, we often perform retrograde or antegrade ureteral pyelography.

Another anatomic problem that we have seen arise in patients with neurogenic bladder and previous bladder reconstruction is ureteropelvic junction obstruction (UPJO). There is a small incidence of UPJO associated with VUR that has been established in pediatric urology. These cases of UPJO may be due to this association, or they may arise secondary to fibrosis surrounding the ureter from ascending infection, stones, or previous manipulation (Fig. 9.4). Other causes are redundancy arising from chronic hydronephrosis secondary to a history of VUR and high-pressure bladder dynamics. Ureteral redundancy can cause a kinking effect in the ureter and in some cases can lead to a functional obstruction. An evaluation can be performed with a nuclear medicine lasix renogram, potentially in combination with retrograde ureteropyelograms [41].

Finally, the shape of the reconstructed bladder itself can be a predisposing factor for recurrent infections, as when the bladder enlarges and gains a saccular shape. This can create a situation in which portions of the bladder are not drained to completion with intermittent catheterization, resulting in urinary stasis. Such a situation can be diagnosed using cystogram before and after catheterization, and may be a diagnosis of exclusion after all other sources of urinary infections has been ruled out. One approach to managing an incompletely draining reconstructed bladder is scheduled manual irrigations through a catheter followed by active aspiration of the irrigant.

A regular schedule of CIC has been shown to be safe and effective in the long term and can avoid bladder distention and high intraluminal pressures, allowing bacteria introduced by CIC to be neutralized. The rate of UTI and bacteriuria, as well as other urologic complications are lower in patients who use CIC compared to indwelling catheters, and thus is the recommended option [42].

In a bladder with normal capacity and compliance, the frequency of catheterization is every 4–6 h, with an aim to maintain bladder volumes <500 mL. However, given the varied bladder compliance and capacity in patients with neurogenic or augmented bladders, the regimen must be individualized on a case-by-case basis. Typically 12–16F catheters are used for both adult men and women, with larger catheters employed in augmented bladders requiring irrigation. Clean, as opposed to sterile, intermittent catheterization does not pose an increased risk of symptomatic UTI in SCI patients and has significant cost and time saving benefits [43]. When it comes to catheter selection, there is contradictory evidence about the use of hydrophilic catheters, with some studies showing lower rates of infection and hematuria compared to non-hydrophilic catheters [44].

Of adult patients who have been instructed on CIC, only about 2/3 are compliant with at least 80 % of the initial recommendation at 1 year [45]. Noncompliance with catheterization leads to overflow incontinence, which in itself can contribute to UTI risk [46, 47] as well as higher rates of UTI due to more time spent with elevated intravesical pressure. A very simple way of assessing catheterization volumes, leakage, and patient compliance is to have patients keep a bladder journal for several days.

Once modifiable problems with the urinary tract have been eliminated or treated and UTI remains as a persistent issue, then treatment should focus on prevention of infections. Prevention strategies are best employed in a very systematic and stepwise fashion starting with therapies that minimize chronic antibiotic use. Some of these strategies are in development such as bacterial interference, while others are commonly used. The evidence underlying these strategies is often contradictory or lacking; however, they are often tried in an effort to control UTI in patients who are commonly very affected by their UTI.