Category: Clinical Stones: Outcomes

MP8-1 - Predicting the need for intervention for distal ureteral stones up to 10mm diameter

Fri, Sep 21
10:00 AM - 12:00 PM

Introduction & Objective :

80% of patients with distal ureteral stones smaller than 10mm will ultimately pass the stone while on medical expulsion therapy (MET). Nonetheless, a significant number of patients with distal ureteral stone require emergency room (ER) visits, admission to hospital, readmission and loss of working days before surgical intervention is decided. Our study aims to find predictive variables for the need of surgical intervention.

Methods :

We retrospectively surveyed the medical records of all patients who had non contrast computed tomography (NCCT) at our ER between March 2016 and May 2017 and were found to have a distal ureteral stone up to 10mm in diameter. Demographic, clinical, laboratory and radiological data of the patients were obtained. We then compared the characteristics of patients who required surgical intervention to those who were treated conservatively.

Results :

268 consecutive patients with distal ureteral stones were included. 226 (84%) patients were male and the average age was 46y (13-82). 60 patients (22%) underwent either primary ureteroscopy or renal drainage (group 1) and 208 patients (78%) were treated expectantly (group 2). No statistically significant differences were observed with respect to demographic data or the proportion of patients treated with MET between the groups<./p>

Univariate analysis found the following parameters to be significantly different between the groups: stone diameter, stone to uretero-vesical junction (UVJ) distance, stone Hounsfield units, presence of a "rim sign" on NCCT and the duration of pain at presentation. Multivariate analysis showed stone diameter, stone to UVJ distance and pain duration at presentation to be independently predictive for intervention. ROC curve analysis identified stone size greater than 4mm, stone to UVJ distance greater than 4mm and duration of pain greater than 4 days to be the most significant cutoff points for patient risk stratification. Further analysis showed that the prevalence of intervention among patients with 0, 1, 2 and 3 risk factors was 4.3%, 22.1%, 45% and 66.7% respectively.

Conclusions :

We found that stone size, stone distance from the UVJ and duration of pain play a significant role in predicting intervention. These parameters may aid in early recognition of patients who will ultimately require intervention and may omit the burden of unnecessary expectant management.

Jonathan Modai

Kaplan Medical Center
Tel Aviv, Tel Aviv, Israel

Jonathan Modai, MD, Resident of Urology in Kaplan Medical Center

Yuval Avda

Urology Resident
Kaplan Medical Center
Rehovot, HaMerkaz, Israel

Yuval Avda, MD, Urology resident, Kaplan Medical Center, Rehovot, Israel

Igal Shpunt

Urological Resident
Kaplan Medical Center
Shoham, HaMerkaz, Israel

Dan Leibovici

Rishon le zion, HaMerkaz, Israel

Uri Lindner

Tel Aviv, Tel Aviv, Israel

Yaniv Shilo

Ramat Gan, HaMerkaz, Israel