THE CHANGING URODYNAMIC PATTERN IN VALVE BLADDERS DURING INFANCY

Bladder dysfunction in boys with posterior urethral valves is well doc umented in studies of long-term followup. These reports suggest that d ysfunctional bladders can be divided into 3 main types, including unst able, low compliant and over distended. To our knowledge urodynamic fi ndings at presentation during infancy have not been described previous ly. We report on 16 male patients born between 1989 and 1993 who prese nted with symptoms of posterior urethral valves between birth and age 5 months, and who were followed with repeated urodynamic evaluations f or a mean of 19 months. At presentation the bladder was hypercontracti le with low capacity. During the first 3 years of life, the urodynamic pattern changed with vanishing hypercontractility and increasing blad der capacity, although instability remained unchanged with emptying di fficulties. Thus, the 3 patterns of bladder dysfunction reported in ol der boys after resection of posterior urethral valves could not be fou nd in infants and small children.