Urinary Expression of Novel Tissue Markers of Kidney Injury After Ureteroscopy, Shockwave Lithotripsy, and in Normal Healthy Controls

Abstract

Background and Purpose: Shockwave lithotripsy (SWL) and ureteroscopy (URS) are minimally invasive treatment alternatives for kidney stones. Although less invasive, SWL subjects the renal parenchyma to a high level of energy and the potential to cause renal injury. The ability to detect renal injury post-SWL in a reliable and noninvasive way would be clinically beneficial. Kidney injury molecule 1 (KIM-1) and N-acetyl-b-Dglucosaminidase (NAG) are two proteins secreted by the kidney into the urine and have been found to be sensitive markers of acute kidney injury in transplant patients. The aim of this work was to measure urinary levels of KIM-1 and NAG in patients with kidney stone who were treated by SWL or URS and in nonstone volunteers. Patients and Methods: Patients with kidney stones who were treated by SWL (n = 50) or URS (n = 10) were recruited. Voided urine samples were collected before and 2 to 3 hours after URS and SWL. In addition, further urinary specimens were collected 2 days and 2 weeks post-SWL treatment. Voided urine samples from healthy volunteers were also collected. Results: Mean KIM-1 values were increased in patients with kidney stones when compared with volunteers. KIM-1 and NAG levels significantly increased post-SWL and returned to baseline within 2 weeks post-SWL. Poor kidney function was significantly associated with increased biomarker activity both in baseline and post-SWL measurements. There was no significant change in urinary KIM-1 and NAG concentrations before and after URS. Conclusions: Kim-1 and NAG levels significantly increased post-SWL treatment suggesting a potential role for these urinary markers in identifying patients at higher risk of tissue injury.

Do Multiple Ureteroscopies Alter Long-Term Renal Function? A Study Using Estimated Glomerular Filtration Rate

“…They reported a significant increase in both biomarkers post-SWL (P < 0.001 for each), but no change in KIM-1 or NAG post-URS (P = 0.893, P = 0.674, respectively). 13 Increases in both biomarkers have been shown to correlate with decreased eGFR, 14 supporting our findings that URS is unlikely to negatively affect renal function.…”

Accuracy of Urinary Neutrophil Gelatinase-Associated Lipocalin in Quantifying Acute Kidney Injury after Partial Nephrectomy in Patients with Normal Contralateral Kidney

“…Based on these results, we suggest that an increase in uNGAL may not reflect the degree of AKI severity or postoperative renal function in patients with a normal contralateral kidney and a relatively good preoperative renal function. Moreover, unlike previous studies, our results may be applied to not only PN but also to ureteroscopic or shockwave lithotripsy procedures and in other unilateral renal injury models in healthy patients [ 23 ]. Parekh et al also reported that the changes of several urinary biomarkers for AKI, including uNGAL, were relatively small and were not associated with the extent of structural alteration during ischemia, duration of ischemia, or the transient increases of creatinine in patients undergoing PN.…”

Comparison of treatment outcomes according to output voltage during shockwave lithotripsy for ureteral calculi: a prospective randomized multicenter study

“…Lambert et al [11] also demonstrated less renal damage in the escalating voltage SWL group than in the fixed voltage SWL group by measuring β2-microglobulin and microalbumin in urine voided at 1 week after SWL, because less energy was required for the former group. In contrast to the availability of several validated markers for renal injuries [11,28], there are no specific markers for evaluating ureteral injury after SWL. Although our study did not evaluate ureteral injuries after SWL, a case of renal hematoma requiring admission after SWL occurred in group C. It is conceivable that group E may be more advantageous than group C in achieving comparable SFRs based on tissue injury.…”