“…Obstruction, trauma, chronic irritation including infection and/or urolithiasis, hormonal imbalance, and allergic reactions have been discussed [1,4,8], but a dispositional malformation with an abortive attempt of ureter- al duplication must also be taken into consideration [9]. This thesis is supported by the fact that some polyps appear frequently in the 2nd to 4th decade of life and can even be found in children and newborns.…”