The megacystis-megaureter syndrome.

The term megacystis-megaureter describes the radiologic appearance of a large capacity thin-walled bladder and massive primary vesicoureteral reflux. The pathophysiology of these massively dilated ureters and the large capacity bladder is the constant recycling of large volumes of refluxed urine. We treated 29 children between 1 day and 13 years old with this syndrome. Urinary tract infection was present in 74 per cent of the cases. Of these children who presented before 1975, 14 were misdiagnosed primarily as having bladder outlet obstruction, which resulted in inappropriate treatment in 13 and renal deterioration in 5. The remaining 15 children treated after 1975 by means of antireflux surgery alone have remained well with stable renal function and virtual elimination of residual urine. Initial therapy should be aimed at correction of the massive reflux, rather than surgical reduction of bladder capacity or relief of presumed bladder outlet obstruction.