Onal B et al, 2012: Predictive factors and management of steinstrasse after shock wave lithotripsy in pediatric urolithiasis-a multivariate analysis study
Onal B, Citgez S, Tansu N, Demirdag C, Dogan C, Gonul B, Demirkesen O, Obek C, Erozenci A.
Department of Urology, University of Istanbul Cerrahpasa Medical Faculty, Istanbul, Turkey
OBJECTIVE: To define the predictive factors for the formation of steinstrasse (SS) after shock wave lithotripsy (SWL) and determine the treatment strategies for this complication in pediatric urolithiasis.
METHODS: We retrospectively reviewed the data of 341 renal units (RUs) treated with SWL for urolithiasis. The stone location, stone burden, auxiliary procedures, energy level, and number of shock waves were recorded. Statistical analysis was performed to detect the predictive factors for the formation of SS. In addition, the treatment of children with SS was evaluated.
RESULTS: The mean age of the children was 8.31 years (range 1-17). Episodes of SS developed in 26 RUs (7.6%). Of the 26 RUs, 20 (77%) were localized in the lower, 5 (19%) in the upper, and 1 (4%) in multiple locations in the ureter. The stone burden was the only statistically significant factor predicting the formation of SS on logistic regression analysis (P = .001). Of the 26 RUs, 17 (65.4%) were successfully managed by repeat SWL monotherapy, 4 (15.4%) were managed with ureteroscopy after failure of SWL, 1 (3.8%) was managed by ureteroscopy monotherapy, and 4 (15.4%) were monitored with conservative management with antispasmodic drug plus hydration therapy. The mean number of SWL sessions was 1.72.
CONCLUSION: The incidence of SS development in children after SWL treatment was similar to that in adult series. Our results suggest that the stone burden is a significant predictive factor for the development of SS after SWL in pediatric urolithiasis. Most children with SS could be easily and safely treated by repeat SWL.
Copyright © 2012 Elsevier Inc. All rights reserved
Urology. 2012 Nov;80(5):1127-31. doi: 10.1016/j.urology.2012.06.043. Epub 2012 Sep 19
PMID: 22999455 [PubMed - indexed for MEDLINE]
This is a single operator report on the SWL treatment of children with stones in the kidney or upper or mid ureter between 1992 and 2008. There is a slight discrepancy in the figures: In the table the authors list 341 children, 341 renal units, 209 single and 132 multiple sessions but only 341 anesthesias (31 general and 310 intravenous analgesia). With a mean number of 1,72 SWL sessions it must have been 568 anesthesias. If one adds those procedures for the removal of Steinstrasse the mean number of procedures comes up to 1,87. In addition some children must have had further treatments: The overall stone-free rate for the 341 renal units was 75.1% (85 cases). But the authors do not report on the true SWL failure rate and the secondary procedures after insufficient results with SWL.
“In the present study, SS developed in 7.6% of the children who had undergone SWL treatment and the incidence was similar to that of other studies of adults.” This is a surprisingly bad outcome because the authors also state what is generally agreed to: “We believe, as other investigators have reported, that children eliminate the stone fragments more easily and more quickly after SWL, regardless of the stone location.” In fact the frequency of Steinstrasse in children in the authors series is even higher than that of adults quoted in their article (Sayed MA, el-Taher AM, Aboul-Ella HA, et al. Steinstrasse after extracorporeal shockwave lithotripsy: aetiology, prevention and management. BJU Int. 2001; 88:675-678):
If this manuscript would come from my department I would suggest changing our patient selection and checking our lithotripter to find out if it its function is ok.