Nonneurogenic bladder-sphincter dysfunction

VUD is the combination of VCU with pressure/ flow/electromyographic studies of the lower urinary tract. It is the gold standard for the assessment of children with neurogenic bladder. It is only a second-step study in children with nonneurogenic bladder-sphincter dysfunction. 

The bladder neck is the poorly delineated junction between the bladder and urethra at the level of the internal urethral sphincter. At the beginning of voiding the bladder floor descends and becomes funnel-shaped and in continuity with the proximal urethra. At the end of voiding, the bladder base ascends to its normal position. A wide bladder neck and a dilated proximal urethra during voiding (wide bladder neck anomaly and spinning top urethra, respectively) are variants that will be discussed in Chapter 14 on nonneurogenic bladder-sphincter dysfunction (functional disorders of the lower urinary tract). 

Extremely rare in childhood, the urethral polyp is usually solitary and consists of a pedunculated structure, originating from the posterior urethra, developing in the bladder neck, which can prolapse in the urethra during micturition (Foster and Garrett 1986). Hematuria, nonneurogenic bladder-sphincter dysfunction and infection may reveal the abnormality. On ultrasound, it appears echo-genic. The main differential diagnosis of urethral polyp is an ectopic ureterocele that has ruptured either spontaneously (Fig. 6.8) or after endoscopic... 

Detection of VUR-Circumstances 219 Postnatal Workup of Antenatally Diagnosed Fetal Uropathies 219 Nonneurogenic Bladder-Sphincter Dysfunction 219 Urinary Tract Infection 219 Familial VUR 220 Secondary VUR 220... 

Nonneurogenic Bladder-Sphincter Dysfunction ( Voiding Dysfunction ) in Neonates and Infants 282... 

One or more of the clinical symptoms of nonneurogenic bladder-sphincter dysfunction were reported in 26% of 7-year-old Swedish children most had moderate urgency as a sign of incomplete voluntary bladder control (HellstrOm et al. 1990). 

In addition, numerous definitions and categories are in use for nonneurogenic bladder-sphincter dysfunction, blaming either the bladder or the urethral sphincter for the various clinical expressions of nonneurogenic bladder sphincter-dysfunction. In this chapter not only the whole spectrum of nonneurogenic bladder-sphincter dysfunction will be described, but how dysfunction is embedded into the disease complex UTI-renal damage will be shown. Furthermore, the associations and the causal relationship to VUR, UTI, renal damage and constipation will be discussed and the various clinical manifestations will be elucidated. 

Over the last years numerous articles dealing with all aspects of nonneurogenic bladder-sphincter dysfunction in infants and children have been published. 

A broad spectrum of terms such as nonneuro-pathic vesicourethral dysfunction (Koff 1984), overactivity of the bladder and striated urethral muscle (Van Gool et al. 1984), nonneuropathic or nonneurogenic bladder-sphincter dysfunction (Hoebeke et al. 1999), dysfunctional bladder (Hinman 1986), unstable bladder (Koff 1982), nonneurogenic neurogenic bladder (Allen 1977) and Hinman syndrome (Hinman 1986) is still in use for sometimes overlapping patterns of nonneurogenic bladder-sphincter dysfunction. 

Nonneurogenic neurogenic bladder or the so-called Hinman syndrome is at the extreme end of the spectrum of nonneurogenic bladder-sphincter dysfunction. This syndrome shows severe clinical manifestations including urinary retention, severe bladder-sphincter dysfunction, VUR, hydronephrosis and hydroureter and renal scarring. 

ScHULMAN et al. (1999) described unstable bladder or urge syndrome in 52% of cases of nonneurogenic bladder-sphincter dysfunction followed by dysfunctional voiding in 25%. Himsl and Hurwitz (1991) state as well that the underlying problem in the great majority of children with functional disorders of the lower urinary tract is unstable bladder. 

The study by Mayo and Burns (1990) and the publication of Hoebeke et al. (1999) show that the number of cases with unstable bladder is around 60%. Passerini-Glazel et al. (1992) describe a rate of unstable bladder of 90% in children with nonneurogenic bladder-sphincter dysfunction. In 156 children with daytime incontinence, Van Gool (1992a) found unstable bladder in 53% and dysfunctional voiding in 59%. Weerasinghe and Malone (1993) reported unstable bladder in 54% and dysfunctional voiding in 3.5%. 

In a study on the utility of video-urodynamics in children with UTI and nonneurogenic bladder sphincter-dysfunction. Glazier et al. (1997) also found a majority of cases with unstable bladder and only 30% of patients with dysfunctional voiding. 

The prevalence of nonneurogenic bladder-sphincter dysfunction ( voiding dysfunction ) in children is high. One or more symptoms of disturbed bladder function were reported in up to 26% of children. Overactive bladder (unstable bladder) turned out to be the most common dysfunction. 

Nonneurogenic bladder-sphincter dysfunction is thought to originate from behavioral factors that affect toilet training and inhibit the maturation of normal urinary control. Since the gastrointestinal tract plays a prominent role in lower urinary tract dysfunction, the term dysfunctional elimination syndromes (Koff et al.l998) is applied, if functional bowel disturbances are associated in terms of chronic constipation and encopresis. 

Functional obstruction is the central problem in nonneurogenic bladder-sphincter dysfunction. Bladder distortion, VUR, upper urinary tract dilatation, UTI and reflux nephropathy are potential consequences. 

Fecal and urinary incontinence are significantly more commonly observed in constipated than non-constipated children. Constipation and/or encopresis is commonly associated with nonneurogenic bladder-sphincter dysfunction. Comprehensive treatment is mandatory for successful management of affected children. Idiopathic urethritis might be a manifestation of underlying dysfunctional elimination syndromes. 

Girls evaluated for UTl after toilet training have in 50-60% of cases typical symptoms of unstable bladder. Koff and Murtagh (1983) reported that unstable bladder was present in 54% of children with VUR. Snodgrass (1998) reported an incidence of 33%. These authors concluded that unstable bladder might be the most common nonneurogenic bladder-sphincter dysfunction associated with VUR. Similarly, Homsy et al. (1985) demonstrated a doubled VUR resolution rate in children treated with anticholinergics compared to that in a historical control. 

But children with VUR, nonneurogenic bladder-sphincter dysfunction and dysfunctional elimination syndromes remain at significant risk for a breakthrough UTI despite antibiotic prophylaxis, anticholinergic therapy, timed voiding and regular bowel evacuation (Koff et al. 1998). 

Nonneurogenic bladder-sphincter dysfunction in patients with renal transplantation may have a negative effect on the transplanted kidney (Van der Weide et al. 2006 Luke et al. 2003 Adams et al. 2004). In a study by Luke et al. (2003) comparing the long-term outcomes of graft survival between children with dysfunctional lower urinary tract and children with a normal lower urinary tract, it was found that lower urinary tract pressure plays an important role in graft survival. 

Incontinence is the involuntary loss of urine together with nonneurogenic bladder-sphincter dysfunction often in combination with UTI, constipation and fecal incontinence. 

Most cases of daytime and nighttime wetting are functional forms of urinary incontinence resulting from nonneurogenic bladder sphincter dysfunction, clinically manifested by frequency, urgency and urge incontinence. UTls, covered bac-teriuria, VUR, constipation, encopresis and structural abnormalities of the urinary tract are often associated. 

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