Bowel and Bladder Dysfunction

Bowel and bladder dysfunction (BBD) can manifest as any abnormality in elimination. This increasingly recognized pediatric condition is characterized by both lower urinary tract symptoms and constipation and/or encopresis that can result in substantial lower urinary tract and kidney problems (including vesicoureteral reflux [VUR] and recurrent urinary tract infections [UTIs]). Accompanying physical, behavioral, and psychosocial problems include ADHD, impulsivity, and poor school performance. The most severe cases of BBD can result in renal functional impairment and even kidney failure.

It is important to note and assess whether BBD is accompanied by UTIs and/or symptoms of markedly dysfunctional voiding. The presence of BBD may signify a higher likelihood of VUR and of recurrent febrile UTIs. In a prospective report that included two separate cohorts of children with histories of UTIs (the placebo recipients with VUR in the Randomized Intervention for Vesicoureteral Reflux [RIVUR] study and children without VUR in the Careful Urinary Tract Infection Evaluation [CUTIE] study), analysis using recurrent UTIs as an outcome showed that children who had both VUR and BBD were more likely to develop symptomatic febrile UTIs over time and, thus, to potentially benefit from antibiotic prophylaxis.

Prompt diagnosis and treatment of BBD are important to avoid progression and psychosocial stigma. Most patients do improve with urotherapy and treatment of constipation.

Epidemiology

The prevalence of BBD is variable and uncertain because it is underreported. Although the prevalence is low in the general community, the prevalence is high (approaching 50%) among children referred to urologists due to the referral nature of specialties. Further, among children with functional constipation, urinary symptoms are common; in a systematic review the prevalence of single bladder symptoms varied from 2% to 47%, lower urinary tract symptoms from 37% to 64%, and urinary tract infections from 6% to 53%.

Diagnosis

• History and physical examination are more important for diagnosis of BBD than testing. The diagnosis often is suggested during a careful history by reports of wetting events, infrequent voiding, and encopresis and constipation. A history of UTIs is also common. Other coexisting conditions include obesity and psychiatric and developmental disorders.

• Urinalysis and urine culture are often reasonable investigative tests to rule out other abnormalities (e.g., UTI, albuminuria, hematuria, glucosuria).

• Imaging studies and urodynamic studies are not routine and should be used on an individualized basis.

• A voiding diary and questionnaire about voiding and stooling patterns can provide important diagnostic information. The Dysfunctional Voiding Scoring System is a validated questionnaire for evaluation of dysfunctional voiding symptoms in children.

Management

Nonpharmacologic Therapy

Many children will experience improvement from behavioral changes, urotherapy, and constipation treatment.

Urotherapy

• Increase hydration.

  • Adequate fluid intake varies but is generally a cup of water after every voiding episode.

• Educate child and caregiver on proper voiding technique and timing.

  • Demonstrate positioning for voiding, especially in girls, with instruction on pelvic floor muscle awareness and pelvic tilt exercises.

  • Consider biofeedback therapy.

  • Institute a regimen of timed voiding, every 2 to 3 hours while awake.

• Provide instruction on personal hygiene.

  • Double voiding (voiding to completion and then resting before trying again) may help improve voiding hygiene.

Constipation treatment

• adequate fluid and fiber intake

• stool softeners or polyethylene glycol

• stool hygiene education

• disimpaction (if a child is impacted)

• techniques to prevent stool reaccumulation

• ongoing follow-up

(Source: Bladder and Bowel Dysfunction in Children: An Update on the Diagnosis and Treatment of a Common, but Underdiagnosed Pediatric Problem. Can Urol Assoc J 2017.)

Pharmacotherapy

Pharmacotherapy beyond stool softeners for voiding dysfunction should be considered if no improvement occurs after 6 months of nonpharmacologic treatment. Obtain a urodynamic study before choosing pharmacotherapy because the results may clarify the nature of the dysfunctional voiding.

• prophylactic antibiotics

  • Consider prophylactic antibiotics in children with BBD accompanied by UTIs and VUR, particularly with evidence of high-grade reflux or renal cortical scarring.

• anticholinergic agents, beta3-adrenoceptor agonists, and selective alpha-blockers (see the following points and the algorithm for diagnosis and management of BBD below)

  • Anticholinergic agents (e.g., oxybutynin) may be useful for treating overactive bladder and urinary incontinence.

  • Beta3-agonists (e.g., mirabegron) can be used for refractory overactive bladder.

  • Alpha-blockers (e.g., tamsulosin, doxazosin, or silodosin) can be useful for treating primary bladder neck dysfunction by relaxing the external sphincter (an off-label use).

• Botulinum toxin A

  • This is used (off-label) in some patients who are refractory to oral pharmacotherapy.

Abbreviations: LUT, lower urinary tract; OAB, overactive bladder; Pos Hx UTI, positive history of a documented urinary tract infection (usually febrile); RBUS, renal and bladder ultrasound; UA, urinalysis; UDS, urodynamic study; uroflow with EMG and PVR, uroflowmetry with electromyography and post-void residual; VCUG, voiding cystourethrogram (Source: Bladder and Bowel Dysfunction in Children: An Update on the Diagnosis and Treatment of a Common, but Underdiagnosed Pediatric Problem. Can Urol Assoc J 2017.)