Factors affecting spontaneous passage in ureteric stones

Purpose: We aimed to investigate associated factors with spontaneous passage of ureteral stones. Materials and metods: One hundred and thirteen patients with ureteral stones (n:60 experienced spontaneus passage/Group A, n:53 did not/Group B) prospectively included to the study between November 2018 and March 2020. Number, hardness, side, localisation, burden and size of the stone, age, gender, history of stone surgery and SWL, hematuria, pyuria and serum biochemical parameters, white blood cell and CRP levels were compared between the two groups. Results: Mean age of the patients in Group A and B were 42,6 ± 1,9 and 47,1 ± 2,1 years, respectively (p=0,122). Male/female rate of the groups were 0,33 and 0,47, respectively (p=0,266). Median stone size (5,5 mm vs. 7 mm) and stone burden (20,5 mm² vs. 36 mm² ) were statistically lower in Group A (p=0,001 and p:0,01, respectively). The Hounsfield unit (HU) of the stones was 738 ± 38 HU in Group A and 884 ± 37 Group B (p=0,007). Fifty-six patients (93,3%) had soft stones in Group A and 36 (67,9%) patients had soft stones in Group B (p=0,001). Lower CRP level was statistically associated with spontaneous passage (26,7% vs. 50,9%; p=0,007). Hematüria was also associated with spontaneus passage (80% vs. 62,3%; p=0,041) Stone composition and other parameters were not associated with spontaneous passage of the ureteral stones. Conclusion: As a conclusion, stone burden, HU and hardness of the stone, hematuria and serum CRP levels are associated with spontaneous passage of the ureteral stones. It is important to consider these parameters in patients with ureteral calculi before active surviellance.