title: Factors predicting the spontaneous passage of a ureteric calculus of ⩽10 mm.
abstract: OBJECTIVE
  To evaluate the outcome of the expectant management of ureteric stones and to determine the factors predictive of the spontaneous passage of stones.
  
  
  METHODS
  We retrospectively reviewed the medical records of patients who had ureteric stones of ⩽10 mm and who were treated conservatively at our institutions during the period 2008-2013. The stone-passage rate and time, and different clinical, laboratory and radiological variables, were analysed.
  
  
  RESULTS
  In all, 163 patients with ureteric stones were enrolled in the study, of whom 127 (77.9%) passed their stones spontaneously, with a mean (SD) passage time of 24.0 (8.09) days. The cumulative stone-passage rate was 1.6%, 15%, 41.7%, 72.4%, 89.8% and 98.4% at 7, 14, 21, 28, 35 and 42 days from the first presentation, respectively. Patients with a high pain-scale score, stones of ⩽5 mm, a lower ureteric stone, a high white blood cell count and those with absent computed tomography (CT) findings of perinephric fat stranding (PFS) and tissue-rim sign (TRS) had a higher likelihood of spontaneous stone passage. Patients with stones of ⩽5 mm, stones in the lower ureter and those with no PFS had a shorter spontaneous passage time. In a multivariate analysis the absence of PFS and TRS were the only significant predictors for spontaneous stone passage (P < 0.001 and 0.002, respectively).
  
  
  CONCLUSIONS
  The spontaneous ureteric stone-passage rate and time varies with different factors. The absence of CT findings of PFS and TRS are significant predictors for stone passage, and should be considered when choosing the expectant management.
authors.affiliation: Department of Urology, Al-Azhar University, Cairo, Egypt ; Department of Urology, Salman Bin Abdul-Aziz University, Al-kharj, Saudi Arabia.
authors.forename: Abul-Fotouh
authors.initials: AF
authors.lastname: Ahmed
authors.affiliation: Department of Urology, Salman Bin Abdul-Aziz University, Al-kharj, Saudi Arabia ; Department of Urology, Minia University, Minia, Egypt.
authors.forename: Ahmed H
authors.initials: AH
authors.lastname: Gabr
authors.affiliation: Department of Urology, Al-Azhar University, Cairo, Egypt ; Department of Urology, Ghodran Hospital, Baljurashi, Saudi Arabia.
authors.forename: Abdel-Aziz
authors.initials: AA
authors.lastname: Emara
authors.affiliation: Department of Urology, Al-Azhar University, Cairo, Egypt ; Department of Urology, King Khalid Hospital, Tabouk, Saudi Arabia.
authors.forename: Mahmoud
authors.initials: M
authors.lastname: Ali
authors.affiliation: Department of Urology, Al-Azhar University, Damietta, Egypt ; Department of Urology, Al-Rafie Hospital, Makkah, Saudi Arabia.
authors.forename: Al-Sayed
authors.initials: AS
authors.lastname: Abdel-Aziz
authors.affiliation: Department of Urology, Salman Bin Abdul-Aziz University, Al-kharj, Saudi Arabia.
authors.forename: Saad
authors.initials: S
authors.lastname: Alshahrani
keywords: BMI, body mass index; PFS, perinephric fat stranding; Predictors; RBC, red blood cells; SPR, spontaneous (stone) passage rate; Spontaneous passage; TRS, tissue-rim sign; UHCT, unenhanced helical CT; Ureteric calculi; WBC, white blood cells