Terminology for children with bowel and bladder dysfunction is confusing, and only in the last decade has there been consensus regarding these terms. This is divided into:
- Lower urinary tract dysfunction
- Daytime urinary incontinence (DUI)
- Enuresis or nocturnal enuresis - see Enuresis - night wetting pre-referral guideline.
- Bowel dysfunction (encopresis) - see Encopresis pre-referral guideline
Urinary Incontinence is defined as involuntary leakage of urine. Unlike in adults, where daytime wetting is always pathological, toilet training occurs at varying ages for different children. However, any child who wets during the day beyond age 5 is diagnosable with DUI, and should be further examined and investigated.
Daytime urinary incontinence (DUI) is either
- Intermittent DUI (most common)
- Overactive bladder (OAB) - previously referred to a detrusor instability
- over sensitive bladder that 'triggers' when only partially full
- urgency +/- frequency +/- holding manoeuvres ('Vincent's curtsy' or 'hocking')
- very wet underpants
- tower curve on uroflow (high pressure urine stream)
- Dysfunctional voiding (DV)
- habitually contract sphincter or pelvic floor whilst voiding
- urge incontinence, voiding postponement, need to push to urinate, multiple frequent voids
- more commonly UTIs
- staccato curve or interrupted curve on uroflow
- Overactive bladder (OAB) - previously referred to a detrusor instability
- Continuous DUI (rare)
- suspicious for anatomical abnormality (e.g. ectopic ureter) - requires urology referral
Differentials
Constipation - take a history and perform an abdominal examination to exclude constipation. Any rectal overload puts pressure on the bladder, decreasing its capacity, and increasing urinary symptoms. See Constipation for more details.
Nerve involvement or structural problems - examination of the spine (back) and the bladder opening to exclude any nerve involvement or structural problems.
UTI and diabetes - urine culture and urinary glucose to exclude these causes of urinary frequency.
- Any child who wets during the day beyond age 5 should be further examined and investigated.
- Daytime urinary incontinence needs to be separated into intermittent (either overactive bladder or dysfunctional voiding) or continuous (rare)
- Baseline renal ultrasound is required for prevoid and post void bladder volumes, and to look for signs of hydronephrosis.
- Overactive bladder is managed with behaviour modification and bladder training before consideration of oxybutynin (Ditropan).
Investigations
- Renal ultrasound - please request prevoid and post void bladder volumes, and to look for signs of hydronephrosis.
- Uroflow, or uroflowmetry provides a graph, looking at urine output against time. A uroflow machine is available at the Continence Clinic (see below). This gives valuable information about bladder contractility and bladder outlet obstruction, and should be considered if concerned about OAB or DV symptoms.
- Micturating cystourethrogram (MCU/MCUG) has no place in the routine assessment of urinary incontinence in children.
Management
Simple management steps should include:
- Demystify and educate - wetting is a developmentally normal process for many children.
- Remove blame - most parents will say that their child waits too long to go to the toilet. However, in reality it is the child’s bladder that contracts too early. Holding maneuvers which stop the child from having an accident caused by OAB is protective, and not a sign that the child is being lazy or waiting too long.
- Unrestricted fluid intake - despite what seems logical, there is no evidence that fluid restriction helps, and may lead to dehydration and increased risk of UTI.
- Perform a voiding diary for at least 48 hours to help to clarify pattern of wetting.
Specific management:
- Overactive bladder is always first managed with behaviour modification and bladder training.
- Oxybutynin (Ditropan)
- anticholinergic drug to decrease the spasm of overactive bladder
- it is reasonable to consider ditropan if:
- the symptoms are consistent with OAB
- there has first been a renal ultrasound showing no significant post void residual volume (if evidence of residual volume >20ml age 4-6, >10ml age 7 and over, refer to continence clinic)
- attempt wean within 6 months - if symptoms recur, refer to Continence Clinic (below) for uroflow and monitoring residual bladder volumes every 3 to 6 months.
- Paediatrician
- generally a non-urgent referral to paediatric outpatient services to i) confirm diagnosis, ii) discuss management strategies and iii) consider appropriateness of medication.
- Information to bring to any appointments:
- Voiding diary - at least 48 hours recording is needed, but the more the better
- Renal ultrasound result
- Paediatric Continence Service
- referrals to Dr Mark Nethercote, Queen Elizabeth Centre, 102 Ascot Street South, Ballarat 3350, fax 53203737
- All patients are seen by a Continence Nurse initially, who performs and intake assessment and management plan.
- If deemed necessary, the Continence Nurse will on-refer to Dr Mark Nethercote, the Paediatrician attached to the Continence Service.
- Private continence management
- Bronwyn Peck, ndiscnc@gmail.com, flyer