P. Hoebeke et al., One thousand video-urodynamic studies in children with non-neurogenic bladder sphincter dysfunction, BJU INT, 87(6), 2001, pp. 575-580
Objective To ascertain the aetiology and epidemiology of non-neurogenic bla
dder sphincter dysfunction (NNBSD) by assessing the results of prospective
video-urodynamic studies (VUD) in 1000 children.
Patients and methods During a 4-year study period (January 1995 to December
1998) 1000 children prospectively underwent VUD to further define their NN
BSD. After a noninvasive screening assessment consisting of a history, void
ing diary. clinical examination, urine analysis, ultrasonography and uroflo
wmetry, those children who would benefit from further VUD were selected. Th
e selection criteria included a history of urinary tract infection (UTI), a
small bladder capacity not responding to training, dysfunctional uroflow,
ultrasonographic abnormalities and resistance to therapy. During the study
period 3500 children were screened for incontinence problems. including mon
osymptomatic nocturnal enuresis; 1000 of these were selected for VUD (524 b
oys and 476 girls).
Results The urodynamic diagnosis was of normal bladder-sphincter function i
n 62 (6.2%, male:female 44:56), urge syndrome in 582 (58%, 58:42). dysfunct
ional voiding in 316 (32%,, 49:51) and 'lazy bladder' in 40 (4%, 20:80). Bo
ys diagnosed with a 'lazy bladder' were younger than those with urge syndro
me and dysfunctional voiding, Girls with dysfunctional voiding were younger
than those with urge syndrome, The incidence of UTI was significantly high
er in girls than in boys: boys with NNBSD had no greater risk for UTI and i
n girls the general risk was 34%. Only in girls with a lazy bladder was the
re a significantly higher incidence of UTI (53%). Reflux occurred equally i
n all groups, with an overall incidence of 15%. The incidence of obstipatio
n was significantly higher in girls with a lazy bladder. and overall was 17
%.
Conclusion These results from a large series provide a new insight into the
epidemiology and pathophysiology of NNBSD. The age distribution provides e
vidence against a dysfunctional voiding sequence. The risk of developing UT
I in NNBSD is greater only in girls. In children with a lazy bladder the ri
sk is also significantly higher, indicating that residual urine is a greate
r risk factor than detrusor instability. Urge syndrome and dysfunctional vo
iding in girls carry the same risk for developing UTI, indicating that blad
der instability is a higher risk factor for UTI than detrusor sphincter dis
coordination. All dysfunctions carry an equal risk for developing secondary
reflux. Children with NNBSD have different primary diseases but all have a
common risk of incontinence. UTIs, reflux and obstipation.