Indian Journal of Urology
UROSCAN
Year
: 2012  |  Volume : 28  |  Issue : 4  |  Page : 472--473

Is it necessary to treat all patients with silent ureteral stones? Ongoing dilemma!


Jai Prakash 
 ,

Correspondence Address:




How to cite this article:
Prakash J. Is it necessary to treat all patients with silent ureteral stones? Ongoing dilemma!.Indian J Urol 2012;28:472-473


How to cite this URL:
Prakash J. Is it necessary to treat all patients with silent ureteral stones? Ongoing dilemma!. Indian J Urol [serial online] 2012 [cited 2022 Jun 30 ];28:472-473
Available from: https://www.indianjurol.com/text.asp?2012/28/4/472/105805


Full Text

 Summary



The authors performed a retrospective analysis of patients treated between January 2005 and May 2010 to expose the impact of silent ureteral stone on renal function. Patients referred to urology emergency division or elective offices' setting for the evaluation of ureteral calculi were included in the study. Indications for intervention were presence of hydronephrosis, decreased renal function and development of pain and infection.

Silent ureteral stones were defined as calculi found in the absence of any specific or subjective ureteral stone-related symptoms. A total of 506 patients underwent ureteral stone removal during the study period. Stone-free status was defined as the absence of any new calculi-related symptoms and complete absence of ureteral stones on ultrasonography or computed tomography performed 90 days after surgical treatment. Ultrasonography or computed tomography and dimercaptosuccinic acid scintigraphy (DMSA) were performed routinely in all cases three months postoperatively to evaluate for hydronephrosis and renal function.

Of the 506 patients, 27 (5.3%) met the criteria of silent ureteral stones and were categorized as global cohort. Nine patients in the global cohort also had undergone preoperative DMSA and were categorized as kidney function cohort. A difference in relative kidney function of >10% (pre and postoperatively after 90 days) was considered abnormal.

Demographic data were similar in both groups. Silent stones were diagnosed by radiological evaluation for urological disease in 60% cases and for non-urological diseases in 40% cases. The primary therapy was ureterolithotripsy in 24 (88%) patients, ureteroscopy in two patients and laparoscopic ureterolithitomy in one patient. Postoperative serum creatinine remained unaltered. The mean postoperative relative kidney function in global cohort on DMSA was 31% ± 20%. In 63% patients, postoperative DMSA revealed impaired renal function (comparative DMSA difference >10%, as compared to the opposite kidney).Stone size did not affect the pre-or postoperative DMSA findings and resolution of hydronephrosis. Hydronephrosis improved in 70% patients postoperatively. In the kidney function cohort, pre- and postoperative DMSA findings were not significantly different.

 Comments



According to the natural history of urolithiasis, about 20% of patients yearly become symptomatic from a new stone. [1] The management algorithms for both symptomatic and silent renal calculi on the basis of natural history of renal stones have been established. Most of the studies published on the topic of silent ureteral calculi have been case series investigating the natural history of ureterolithiasis or revisions for post-treatment follow-up. [2],[3],[4] But the effect of silent ureteral stone on renal function has not been addressed previously. This report is the first to study the influence of stone removal on the recovery of renal function using pre- and postoperative DMSA analysis in this population.

Complete kidney function loss because of a silent ureteral stone was first reported by Weizer et al.[4] The natural history of silent ureteral stones was first reported by Wimpissinger et al., [5] and found a 1.1% incidence of silent ureteral stone, while in the author's series, silent ureteral stone disease represented 5.3% of all patients needing intervention. This difference might be due to selection bias, because this study includes only patients who were referred for urologic evaluation. The author did not have access to patients with an incidentally discovered ureteral stone who were not referred to an urologist or those with a stone not requiring surgery.

At diagnosis, all patients in the kidney function cohort had significant renal function impairment, although the creatinine levels were normal. Comparative pre- and postoperative DMSA analyses showed no worsening of renal function. Although lesions of nephrons could not be prevented or reversed, stone treatment stabilizes the relative kidney function, and therefore, immediate treatment after diagnosis seems imperative. The authors only considered patients with hydronephrosis, so they cannot speculate whether the same treatment is suitable for patients with an asymptomatic ureteral stone without collecting system dilation.

The author concluded that silent ureteral stones causing hydronephrosis are associated with decreased kidney function present at diagnosis. Although hydronephrosis tends to diminish or resolve after stone removal, renal function is likely to remain unchanged.

The treatment of silent ureteral stone at diagnosis might slow or stop continuous renal scarring and preserve kidney function. But whether all patients of silent ureteral stones irrespective of hydronephrosis should be treated surgically to prevent further renal damage is still a dilemma and cannot be answered on the basis of this study because the authors did not include such a cohort. Although difficult to perform, a prospective randomized trial comparing the pre- and postoperative DMSA results of patients with silent stone in the absence of hydronephrosis is needed before answering that question.

References

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