title: Long-term bladder function followup in boys with posterior urethral valves: comparison of noninvasive vs invasive urodynamic studies.
abstract: OBJECTIVE
  We studied whether noninvasive urodynamic evaluation can be as effective and safe as invasive urodynamics in detecting lower urinary tract dysfunction and in preventing late onset renal failure during long-term management of boys with posterior urethral valves.
  
  
  METHODS
  We evaluated 47 boys with posterior urethral valves using repeat urodynamics. A total of 28 patients with followup of at least 3 years and repeat evaluation of serum creatinine were included in the study. The first 14 boys in the series underwent cystometry and pressure-flow study at least every 3 years (group A), and the remaining 14 patients were monitored annually from age 5 with bladder diary, uroflowmetry, post-void residual urine on ultrasound and serum creatinine (group B). Lower urinary tract dysfunction and serum creatinine were compared (Fisher exact test and Mann-Whitney test) between groups A and B, and by stratifying patients into subgroups by age (5 to 6, 7 to 13 and older than 13 years). In all patients urodynamic diagnosis of lower urinary tract dysfunction was matched and confirmed with lower urinary tract symptoms.
  
  
  RESULTS
  During followup the prevalence of lower urinary tract dysfunction did not differ significantly between group A (71% in boys 5 to 6, 43% in boys 7 to 13 and 85% in boys older than 13 years) and group B (36%, 43% and 60%, respectively). Late onset renal failure was observed in 2 boys in group A and 2 in group B.
  
  
  CONCLUSIONS
  Noninvasive urodynamic evaluation seems to be as safe and effective as invasive urodynamic study in the long-term management of boys with posterior urethral valves. Based on these findings, invasive urodynamics may be reserved for cases of progressive deterioration of lower urinary tract dysfunction or renal function.
authors: Urodynamic Unit, Department of Nephrology and Urology, Ospedale Bambino Gesu, Rome, Italy. mluisa.capitanucci@opbg.net
authors: Maria Luisa
authors: ML
authors: Capitanucci
authors: Armando
authors: A
authors: Marciano
authors: Antonio
authors: A
authors: Zaccara
authors: Edoardo
authors: E
authors: La Sala
authors: Giovanni
authors: G
authors: Mosiello
authors: Mario
authors: M
authors: De Gennaro
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D003950:Diagnostic Techniques, Urological; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D013997:Time Factors; D014521:Urethra / Q000002:abnormalities* / Q000503:physiopathology*; D001743:Urinary Bladder / Q000503:physiopathology*; D014563:Urodynamics