Vesicoureteral reflux and lower urinary tract dysfunction: evidence for 2 different reflux/dysfunction complexes.

We examined retrospectively 458 children 2 to 15 years old without neuropathic conditions or a gross anatomical abnormality to determine whether there was an association between lower urinary tract dysfunction and vesicoureteral reflux. We identified 2 different types of reflux/dysfunction complexes with contrasting urodynamic characteristics. One type included bladder instability with powerful voiding contractions of the bladder and reflux that frequently occurred on 1 side only. Reflux nephropathy or the presence of an upper urinary tract abnormality is rare. In the other type the bladder contracted poorly during voiding and overactivity of the urethral closure mechanism often was observed. The bladder usually was stable and the reflux occurred frequently on both sides. Reflux nephropathy or the presence of an upper urinary tract abnormality is relatively common. Direct videourodynamic observations of reflux in a second group of children confirmed the existence of these 2 types of reflux/dysfunction complexes.