135 / 492
14:01 - 14:04
S9-4
(PP)
★
WHAT HAPPENS TO THE ASYMPTOMATIC LOWER CALYX KIDNEY STONES
SMALLER THAN 10 MM IN CHILDREN DURING WATCHFUL WAITING?
Nurullah HAMIDI
1
, Onur TELLI
1
, Uygar BAGCI
1
, Arif DEMIRBAS
2
, Tolga KARAKAN
2
, Tarkan SOYGUR
1
and Berk BURGU
1
1) Ankara University, Pediatric Urology, Ankara, TURKEY - 2) Ankara Training and Research Hospital, Urology, Ankara,
TURKEY
PURPOSE
To present the outcomes of asymptomatic isolated lower pole kidney stones (LPKS) less than<10mm.
MATERIAL AND METHODS
242 patients with 284 renal units(RU) who presented at two referral centers between June 2004 and December 2014
with asymptomatic single LPKS<10 mm were enrolled in the study.All children were observed as first line
therapy.Patients after a mean follow-up 3.4±1.7 years were categorized as follows those that required an intervention
of flexible ureteroscopy (F-URS) or microPCNL in 72RU (25.4%, group1), shockwave lithotripsy (SWL) in 102RU
(35.9%, group2) and remaining 110RU (38.7%) were categorized as group 3 (observation).Age, gender, stone
laterality, stone size and type, associated urinary tract problems, uncontrolled metabolic status were used to determine
predictive factors that require an intervention of asymptomatic LPKS less than 10mm.Mean operative and fluoroscopy
time, stone free rates, hospitalization time, need for multiple interventions and complications (Clavien score) were
analyzed.
RESULTS
The mean age was 9.4±1.9 years during admission and the mean time for intervention was 19.2±4.6 months. The
stone free rates were 81.8% in group-1, 79.3% in group-2, 9.1% in group-3 (p=0.017). Complication rates for groups 1
and 2 were similar. In the multivariate analysis stone size larger than 7mm, accompanied renal anomalies, struvite and
cysteine stones, and uncontrolled metabolic status were statistically significant predictors. Stone size and age were
significantly related to complications in univariate analysis.
CONCLUSIONS
Stones larger than 7 mm, with renal anomaly and metabolic active cystine and struvite stones are more likely to require
an intervention when asymptomatic LPKS less than <10 mm are under follow up.When SWL, F-URS and micro PCNL are
required deliberate timing, considering age versus stone enlargement should be done to minimize complications for the
management of LPKS.