The following are acceptable first-line treatments for a 1.5 cm renal pelvic stone in a patient with a normal contralateral kidney, except:
A. ESWLAnswer E
A patient with a large stone in the renal pelvis should be fully counselled regarding the treatments that are available to them. A surveillance approach is seldom appropriate for a stone of this size given the high risk of potential complications. For patients with asymptomatic renal stones smaller than 1.5 cm, observation may be appropriate if they are fully informed of the risk of experiencing a symptomatic episode and the potential need for intervention. For example, in a cohort study that included 107 patients, the cumulative 5-year incidence of a symptomatic episode was 48.5%. On the other hand, a prospective randomised controlled trial that compared surveillance with ESWL for small asymptomatic calyceal stones found no significant differences in stone-free rate, quality of life, renal function, symptoms or hospital admissions. However, surveillance was associated with a greater risk of needing more invasive treatment.
For a stone of this size (1.5 cm) located in the renal pelvis or upper or mid-zone calyces, ESWL may be effective but the patient should be advised that more than one treatment may be required. ESWL should not be considered first-line treatment for stones larger than 1.5 cm situated in lower pole calyces because of unfavourable outcomes. Similarly, stone size is inversely proportional to the effectiveness of flexible ureteroscopy and patients with large renal stones should be warned of the potential need for a staged procedure.
PCNL should be considered for stones larger than 2 cm because of reduced effectiveness of ESWL, the potential need for multiple treatments and the increased risk of complications such as colic and steinstrasse. PCNL may also be appropriate for a 1.5-cm stone in the renal pelvis for a patient who desires a single treatment and accepts the greater risk of significant morbidity compared to ESWL or URS. Laparoscopic or open endopyelotomy is not recommended for stones smaller than 2 cm and is generally reserved for special cases such as large stone burdens, previous failed PCNL, obesity or renal anatomical abnormalities.