Prognostic factors in the conservative treatment of ureteric stones.

A prospective study was made of 125 ureteric stones in order to detect factors which would predict the successful outcome of conservative treatment. The factors studied were the duration of pain prior to presentation, pyuria, haematuria, surface regularity of the stone and the degree of obstruction as seen radiologically. In stones less than or equal to 10 mm in size, conservative treatment was successful when the duration of pain was less than 30 days (39/45), when there was no significant pyuria (53/82), when the stones had an irregular surface (44/65) and when obstruction was only partial (55/88). Since most of these factors were interactive, further statistical analysis showed that duration of pain was the only significant factor in predicting the outcome of conservative treatment. In stones greater than 10 mm in size these factors had no predictive value and only 2/23 were passed spontaneously on conservative treatment.