Hicks JA et al. (2007) Is there an association between functional bladder outlet obstruction and Down's syndrome? J Pediatr Urol 3: 369–374

Urinary tract abnormalities occur in an estimated 3–7% of individuals with Down syndrome (DS). An association between DS in males and bladder-outflow obstruction (BOO) secondary to detrusor sphincter dyssynergia (DSD) has been suggested by a small retrospective study. To confirm or refute the association, Hicks et al. conducted a two-part study in the UK.

The first part was a retrospective case note review that included seven children (six male, one female) with DS who had been diagnosed with probable DSD at a single center in Southampton, UK during a 16-year period; mean follow-up was 5 years and 8 months. Of the seven patients, three required urinary diversion for dilated upper tracts secondary to BOO, highlighting the potential risk of renal injury associated with this condition.

In the second part, families of children with DS (age 5–16 years) were sent a postal questionnaire that aimed to identify urinary dysfunction and symptoms suggestive of BOO. Questionnaire responses were available for only 22 of the 42 children contacted. Bladder dysfunction was reported for 17 of these children (77%), wetting problems for 15 (68%), and 9 (41%) had at least one symptom suggestive of BOO. Hospital assessment of the children with reported bladder dysfunction was limited because only three patients agreed to attend.

The authors recommend that children with DS have a detailed history of bladder function taken because, if symptoms such as wetting are disregarded on the grounds of learning difficulties, untreated BOO might result in renal damage.